Biblio Including Abstracts, when available

Year of Publicationsort descending Title Biblio Citation Authors Abstract Type of Publication Keywords
1985 General hydrology and water quality of Layou river in Dokilnica, Buccament river in St. Vincent and Troui'zassee river in St. Lucia, British West Indies Diaz, P.L.; Lugo, A.E.; McDowell, W.H. Conference Proceedings Water quality
1988 Basidiomycetes reduce export of organic matter from forest slopes Lodge, D.J.; Asbury, C.E.

Export of leaf litter from forest siopes can affect soil organic matter (SOM) concentrations, soil nutrient pools, and consequently foliar nutrient concentrations in vegetation (Lang and Orndorff, 1984). Mechanisms which retain litter are especially important in maintaining soil fertility in montane forests, where a high proportion of the landscape is on steep slopes. Litter retained on slopes decomposes in situ and contributes to SOM and soil nutrients in these sites. In addition, litter mats protect surface soil from erosional losses of SOM and nutrients. (Cogo et al., 1984). This paper presents that binding of leaf litter by basidiomycetous fungi retards the export of organic matter from forests slopes.

Journal Article basidiomycetes; Fungi; organic matter; soil; soil biogeochemistry; soil ecology
1988 Genetic variation and systematics of four taxa of Neotropical walking sticks (Phasmatodea: Phasmatidae) Van Den Bussche, R.A.; Willig, M.R.; Chesser, R.K.; Waide, R.B.

Electrophoretically detectable genetic variation for six isozymes encoded by seven loci was analyzed in four taxa walking sticks (Phasmatidae) that occur in neotropical rainforests in eastern Puerto Rico. No phylogenetic analysis previously has been conducted on any phasmatid. All seven loci exhibited variation among Diapherodes achalus, Lamponius portoricensis, Pseudobacteria yersiniana, and an unnamed taxon (species X). Coefficients of geneti distance between these four taxa ranged from 0.349 to 0.571. The UPGMA of Rogers' genetic distance indicated considerable genic dissimilarity among taxa (two taxa which were least dissimilar connected at a value of 0.350). The four taxa represent a holophyletic group for which an outgroup was not analyzed, this situation, in conjuction with the shor internode distance in the Fitch-Margoliash analysis, provides only limited resolution of the phylogenetic associations among the four taxa.

Journal Article Puerto Rico
1989 Differential seeding and regeneration in openings and beneath closed canopy in sub-tropical wet forest Devoe, N.N.

Two experiments were performed in sub-tropical wet forest (tabonuco (Dacryodes excelsa) type) at El Verde, Puerto Rico. The first compared seed rain beneath closed canopy with that in natural treefall gaps. The purpose was to determine whether differences in seed rain might account for some part of the reported difference in tree regeneration under the two canopy conditions. The second experiment examined regeneration along transects from beneath the forest canopy across large gaps. Plant colonization patterns clearly showed that gaps are non-uniform environments. The correlation of certain attributes (seed weight, dispersal mode, regeneration route, shade tolerance) within species and among groups of species led to the description of regeneration strategies for species in this and similar forest communities. Silvicultural applications are discussed. 33 figs., 33 tabs.

1989 Foraging ecology of a Neotropical folivore, Lamponius portoricensis Rehn (Phasmatodea: Phasmatidae) Sandlin, E.A. Thesis walking stick
1989 An introduction to the physiography and history of the Bisley Experimental Watersheds in the Luquillo Mountains of Puerto Rico Scantena, F.N. Report physiography
1989 Landslide natural disturbance and forest regeneration in the Luquillo Mountains of Puerto Rico Guariguata, M.R. Thesis landslide
1989 A profile of the tabonuco forest in Luquillo Experimental Forest, Puerto Rico Walker, L.A.; Garcia, D.C.; Munoz, B.; Rivera, H.D. Journal Article Tabonuco
1989 A geographically-based microclimatological computer model for mountainous terrain with application to the Luquillo Experimental Forest in Puerto Rico Wooster, K.M. Thesis
1990 Cecropia peltata L. Yagrumo hembra, trumpet tree Silander, S.; Lugo, A.E. Report yagrumo hembra
1990 Culvert flow in small drainages in montane tropical forests: observations from the Luquillo Experimental Forest of Puerto Rico
Scantena, F. N. 1990. Culvert Flow In Small Drainages In Montane Tropical Forests: Observations From The Luquillo Experimental Forest Of Puerto Rico J. H Krishna, Quinones, F., Gomez-Gomez, F., and Morris, G. L. Proceedings of the International Symposium on Tropical Hydrology and Fourth Caribbean Islands Water Resources Congress: 237-246.
Scantena, F.N. Conference Proceedings open-channel
1990 Dacryodes excelsa Vahl. Tabonuco
Lugo, A. E, and F. H Wadsworth. 1990. 2 Dacryodes Excelsa Vahl. Tabonuco. R. M Burns and Honkala, B. H. Washington, DC: USDA Forest Service.
Lugo, A.E.; Wadsworth, F.H. Report Tabonuco
1990 Effects of forest clearing and succession on the carbon and nitrogen content of soils in Puerto Rico and US Virgin Islands Brown, S.; Lugo, A.E. Journal Article U.S. Virgin Islands
1990 Effects of hurricane storm flow on transport of woody debris in a rain forest stream (Luquillo Experimental Forest, Puerto Rico)
Covich, A., and A.T. Crowl. 1990. Effects Of Hurricane Storm Flow On Transport Of Woody Debris In A Rain Forest Stream (Luquillo Experimental Forest, Puerto Rico) J. H Krishna, Quinones, F., Gomez, F., and Morris, G. L. Proceedings of the International Symposium on Tropical Hydrology and Fourth Caribbean Islands Water Resources Congress: 197-205.
Covich, A.; Crowl, A.T. Conference Proceedings downstream transport; Puerto Rico; rain forest; storm flow; woody debris
1990 Endomycorrhizal innoculum on landslides at El Verde Simmons, N. Thesis lanslides
1990 Field guide to the Luquillo Experimental Forest
Scantena, F. N, and M.C. Larsen. 1990. Field Guide To The Luquillo Experimental Forest. American Water Resources Association.
Scantena, F.N.; Larsen, M.C. Report trees
1990 Geomorphic impacts of Hurricane Hugo on the Luquillo Mountains of Puerto Rico: preliminary observations
Scantena, F. N. 1990. Geomorphic Impacts Of Hurricane Hugo On The Luquillo Mountains Of Puerto Rico: Preliminary Observations. In Humid tropical steep lands: research needs and applications to reduce erosion and sedimentation in tropical steeplands, Humid tropical steep lands: research needs and applications to reduce erosion and sedimentation in tropical steeplands, R. R Ziemer, O'Loughlin, C. L, and Hamilton, L.S. Wallingford, England: International Association of Hydrological Sciences Pub. No.192. IAHS Press, 393.
Scantena, F.N. Book Chapter natural impacts
1990 Hygrophoraceae of the Luquillo Mountains of Puerto Rico Lodge, D.J.; Pegler, D.N. Journal Article Puerto Rico
1990 Influence of sea salt aerosols and long range transport on precipitation chemistry at El Verde, Puerto Rico McDowell, W.H.; Gines-Sanchez, C.; Asbury, C.E.; Pérez, C.R.R. Journal Article wet deposition
1990 Landslide disturbance and forest regeneration in the upper Luquillo Mountains of Puerto Rico Guariguata, M.R. Journal Article succession
1990 Landslide Processes in Saprolitic Soils of a Tropical Rain Forest, Puerto Rico
Larsen, M.C., and A. Simon. 1990. Landslide Processes In Saprolitic Soils Of A Tropical Rain Forest, Puerto Rico D.K. Larue and Draper, G. Transactions of the 12th Caribbean Geological Conference: 217-222.
Larsen, M.C.; Simon, A. Conference Proceedings saprolitic material
1990 Notes on the ecology and behavior of Anolis cuvieri(Lacertilia:Iguanidae) in Puerto Rico Losos, E.; Gannon, M.R.; Pfeiffer, W.J.; Waide, R.B. Journal Article telemetry
1990 Nutrients and mass in litter and top soil of ten tropical tree plantations Lugo, A.E.; Cuevas, E.; de Leon, S. Journal Article Terminalia ivorensis tropical tree plantations
1990 Preliminary map showing landslides in El Yunque quadrangle, Puerto Rico Guariguata, M.R.; Larsen, M.C. Report Puerto Rico
1990 Rain forest (Luquillo Experimental Forest) watershed hydrology and landslide problems
Scantena, F. N. 1990. Rain Forest (Luquillo Experimental Forest) Watershed Hydrology And Landslide Problems J. H Krishna, Quinones, F., Gomez-Gomez, F., and Morris, G. L. Proceedings of the International Symposium on Tropical Hydrology and Fourth Caribbean Islands Water Resources Congress: 20-25.
Scantena, F.N. Conference Proceedings watershed hydrology
1990 The role of soil processes in determining mechanisms of slope failure and hillslope development in a humid-tropical forest: eastern Puerto Rico Simon, A.; Larsen, M.C.; Hupp, C.R. Book Chapter soil processes
1990 Selection of riparian buffer zones in humid tropical steep lands
Scantena, F. N. 1990. Selection Of Riparian Buffer Zones In Humid Tropical Steep Lands. In Humid tropical steeplands: research needs and applications to reduce erosion and sedimentation in tropical steep lands, Humid tropical steeplands: research needs and applications to reduce erosion and sedimentation in tropical steep lands, R. R Ziemer, O'Loughlin, C. L, and Hamilton, L.S. Wallingford, England: International Association of Hydrological Sciences (IAHS) Press, 328-337.
Scantena, F.N. Book Chapter watersheds
1990 Studies of ecological and geological factors controlling the pattern of tabonuco forest in the Luquillo Experimental Forest, Puerto Rico Basnet, K. Thesis tabonuco forest
1990 Successional change and species/site relationships in a Puerto Rican tropical forest
Johnston, M. H. 1990. Successional Change And Species/site Relationships In A Puerto Rican Tropical Forest. State University of New York-College of Environmental Science and Forestry.
Johnston, M.H. Thesis tropical forest
1990 Watershed scale rainfall interception on two forested watersheds in the Luquillo Mountains of Puerto Rico Scantena, F.N.

Interception losses were monitored for one year and a related to vegetation characteristics in two forested watersheds in the Luquillo Experimental Forest of Puerto Rico. Total watershed interception was then molded by weighing values throughfall measured in representative areas of different vegetation types by the total watershed area of that vegetation group.
Annual canopy throughfall equaled 59% of annual rainfall whereas stemflow represented up to 2.3%. Canopy throughfall was greatest in gaps and along stream channels with 91% of total falling over 75% of the watershed area. However, 50% of the total stemflow came from less than 12% of the total stems.
Reported values of throughfall in the Tabonuco type forest of the Luquillo Moutains are typically 20 to 30% less than values reported for many montane and lowland tropical forests. These differences usually result from a high frequency, low intensity rainfall regime rather than the physiognomic character of the forest.

Journal Article watersheds
1991 The Effects of Hurricane Hugo in Three Tropical Forests in the U.S. Virgin Islands Reilly, A.E.

Hurricanes frequently affect the forests of St. John, U.S. Virgin Islands, but there has been little study of their effects on the island's vegetation. Hurricane Hugo hit St. John on 17-18 September 1989 Six weeks later damage was assessed in three plots on the island (1.0 or 0.5 ha; in subtropical moist and subtropical dry life zones) that were established and inventoried before the hurricane. Most damage involved loss of small branches; loss of major limbs, crown loss, tip-ups, and snapped stems were less common. Taller and larger diameter trees were usually more severely damaged than shorter and smaller diameter trees; forests on slopes facing hurricane winds were damaged more than leeward forests; low elevations received more damage than higher elevations within each forest plot. Overall, damage to vegetation seemed minor, judging from the relative number of stems in different classes of damage severity.

Journal Article
1991 Hurricane Hugo Wind Damage to Southeastern U.S. Coastal Forest Tree Species Gresham, C.A.; Williams, T.M.; Lipscomb, D.J.

One percent of Hobcaw Forest, a 3077 ha tract in South Carolina's lower coastal plain, was inventoried with fixed area plots within four months after the eye of Hurricane Hugo passed 97 km south of the forest. Results of this sampling confirmed our hypotheses that the amount and nature of hurricane wind damage differed among the tree species sampled. Approximately 73 percent of the 16,870 trees inventoried were either not damaged or had light crown damage. Longleaf pine (Pinus palustris) was less damaged than loblolly pine (Pinus taeda) or pond pine (Pinus serotina). Bald cypress (Tazodium distichum) suffered light crown damage. Upland oak were more heavily damaged that the pine species. Live oak (Quercus virginiana) was less damaged that laurel oak (Quercus laurifolia) and water oak (Quercus nigra). Those tree species commonly found in the lower coastal plain (longleaf pine, bald cypress, and live oak) suffered less damage than species with larger natural ranges.

Journal Article
1991 Above and below ground organic matter storage and production in a tropical pine plantation and a paired broadleaf secondary forest Cuevas, E.; Brown, S.; Lugo, A.E.

The distribution of tree biomass and the allocation of organic matter production were measured in an 11-yr-old Pinus caribaea plantation and a paired broadleaf secondary forest growing under the same climatic conditions. The pine plantation had significantly more mass aboveground than the secondary forest (94.9 vs 35.6 t ha-1 for biomass and 10.5 vs 5.0 t ha-1 for litter), whereas the secondary forest had significantly more fine roots (⩽2 mm diameter) than the pine plantation (10.5 and 1.0 t ha-1, respectively). Standing stock of dead fine roots was higher than aboveground litter in the secondary forest. In contrast, aboveground litter in pine was more than ten times higher than the dead root fraction. Both pine and secondary forests had similar total organic matter productions (19.2 and 19.4 t ha-1 yr-1, respectively) but structural allocation of that production was significantly different between the two forests; 44% of total production was allocated belowground in the secondary forest, whereas 94% was allocated aboveground in pine. The growth strategies represented by fast growth and large structural allocation aboveground, as for pine, and almost half the production allocated belowground, as for the secondary forest, illustrate equally successful, but contrasting growth strategies under the same climate, regardless of soil characteristics. The patterns of accumulation of organic matter in the soil profile indicated contrasting nutrient immobilization and mineralization sites and sources for soil organic matter formation.

Journal Article soil organic matter
1991 Camillea: new combinations and a new species Rogers, J.D.; Laessøe, T.; Lodge, D.J. Journal Article Theaceae
1991 Changes in light availability following Hurricane Hugo in a subtropical montane forest in Puerto Rico Fernandez, E.; Fetcher, N.

The changes in light availability in the understory of a subtropical wet forest (Luquillo Experimental Forest, Puerto Rico) were monitored after the passage of Hurricane Hugo on 18 September 1989 Gallium arsenide phosphide sensors were placed 1 m apart along a 32 m transect. Data were collected for periods of 7-10 d in October and December 1989, and in March, July, and November 1990. Daily histograms were generated for observations of photosynthetic photon flux density (PPFD) taken every two seconds. Mean total daily PPFD was calculated for each sensor in each data set. During the 14 mo after the passage of the hurricane, the PPFD showed a highly skewed distribution with most values <200 $\mu$ mol m$^{-2}$ s$^{-1}$ The maximum spatial heterogeneity was observed in July 1990 because of the shading of some sensors by the growing pioneer vegetation. Median values of total daily PPFD for ten months after the hurricane ranged from 7.7 to 10.8 mol m$^{-2}$ d$^{-1}$, which is similar to values previously observed for large (>400 m$^2$) treefall gaps. Median total daily PPFD fell to 0.8 mol m$^{-2}$ d$^{-1}$ in November 1990 because of almost complete coverage of the transect by a canopy of Cecropia schreberiana Miq. ex. C. peltata. An analysis of semivariance was used to discern patterns of autocorrelation in total daily PPFD along the transect. Through March 1990 patches of high and low light separated by distances of 10-12 m were detected. By July 1990 the patchiness was replaced by a pattern that showed no autocorrelation at distances of 1 m or greater.

Journal Article understory
1991 Comparing tropical and temperate forests
Lugo, A. E, and S. Brown. 1991. Comparing Tropical And Temperate Forests. In Comparative analysis of ecosystems: patterns, mechanisms theories, Comparative analysis of ecosystems: patterns, mechanisms theories, J. Cole, Lovett, G., and Findlay, S. New York: Springer-Verlag, 319-330.
Lugo, A.E.; Brown, S. Book Chapter tropical tree plantations
1991 A comparison of agar film techniques for estimating fungal biovolumes in litter and soil Lodge, D.J.; Ingham, E.R. Journal Article soil ecology
1991 Contribution to the study of the genus Helicopsyche (Trichoptera) from Cuba, Hispaniola, and Puerto Rico Botosaneanu, L.; Jr, O.S.Flint Journal Article Trichoptera
1991 Differential seedling responses to litter after Hurricane Hugo in the Luquillo Experimental Forest, Puerto Rico Guzman, S.; Walker, L.A.

We studied the dynamics of the seedling community in the Luquillo Experimental Forest during one year following Hurricane Hugo, to look at the effect of three litter treatments (continuous litter removal, unaltered litter quantity {control} and continuous litter addition), on seedling emergence, growth, density and mortality. Total seedling densities (for both newly emerged and established seedlings) were highest in the litter removal treatment, suggesting that litter is a major constraint to recruitment of seedlings. However, species differed in their responses to the three treatments: species characteristic of early succession (Chionanthus domingensis and Cecropia schreberiana ex. C. peltata) were densest in the litter removal treatment, while densities of species characteristic of late succession either did not increase (Sloanea berteriana) or declined (Dacryodes excelsa) in the litter removal treatment. Height growth was lowest and mortality generally highest for seedlings in the litter removal treatment. Variability in species responses to litter after the Hurriane may lead to changes in the species composition of the forest.

Journal Article undergrowth
1991 Ecological effects of hurricanes
Ackerman, J.D., L. A Walker, F. N Scantena, and J. M Wunderle, Jr. 1991. Ecological Effects Of Hurricanes. Bulletin of the Ecological Society of America 72: 178-189.
Ackerman, J.D.; Walker, L.A.; Scantena, F.N.; Wunderle, J.M. Journal Article vegetation damage
1991 Ecosystem, plant, and animal responses to hurricane in the Caribbean Walker, L.A.; N. V. L. Brokaw; Lodge, D.J.; Waide, R.B. Journal Article tropical forest
1991 The effect of human activity on the structure and composition of a tropical forest in Puerto Rico Garcia-Montiel, D. Thesis Puerto Rico
1991 The effect of Hurricane Hugo on bird populations in the Luquillo Experimental Forest, Puerto Rico Waide, R.B. Journal Article Puerto Rico
1991 The effect of Hurricane Hugo on six invertebrate species in the Luquillo Experimental Forest of Puerto Rico Willig, M.R.; Camilo, G. Journal Article walking sticks
1991 The effects of Caribbean hurricanes on vegetation N. V. L. Brokaw; Walker, L.A. Journal Article vegetation response
1991 Effects of Hurricane Hugo on Manilkarabidentata, a primary tree species in the Luquillo Experimental Forest of Puerto Rico You, C.; Petty, W.H. Journal Article Puerto Rico
1991 The effects of natural and human disturbances on soil nitrogen dynamics and trace gas fluxes in a Puerto Rican wet forest Steudler, P.A.; Melillo, J.M.; Bowden, R.D.; de Castro, F.; Lugo, A.E. Journal Article tropical forest
1991 Effects of tree fall gaps on a tropical land snail community Alvarez, J. Thesis snails
1991 Fine litter fall and related nutrient inputs resulting from Hurricane Hugo in subtropical wet and lower montane rain forests of Puerto Rico Lodge, D.J.; Scantena, F.N.; Asbury, C.E.; Sanchez, M.J.

On September 18th 1989, Hurricane Hugo defoliated large forested areas of northeastern Puerto Rico. In two severely damaged subtropical wet forest sites, a mean of 1006-1083 g/m^2, or 419-451 times the mean daily input of fine litter (leaves, small wood, and miscellaneous debris) was deposited on the forest floor. An additional 928 g/m^2 of litter was suspended above the ground. A lower montane forest site received 682 times the mean daily fine litter fall. The concentrations of N and P in the hurricane leaf litter ranged from 1.1 to 1.5 and 1.7 to 3.3 times the concentrations of N and P in the normal leaf-fall, respectively. In the subtropical wet forest, fine litter-fall from the hurricane contained 1.3 and 1.5-2.4 times the mean annual litter-fall inputs of N and P, respectively. These sudden high nutrient inputs apparently altered nutrient cycling.

Journal Article wet forest
1991 Fine root dynamics in a subtropical wet forest following hurricane disturbance in Puerto Rico Parrotta, J.A.; Lodge, D.J. Journal Article wet forest
1991 Food selection of a tropical mammalian folivore in relation to leaf- nutrient content Willig, M.R.; Lacher, T.E. Journal Article tropical rodent
1991 Foraging ecology, reproductive biology, and systematics of the red fig-eating bat (Stenoderma rufum) in the tabonuco rain forest of Puerto Rico Gannon, M.R.

The mental health field faces a steadily increasing demand for services and traditional methods seem unlikely to meet that demand. The search for more effective and more efficient approaches to mental health problems has intensified. Increased use of paraprofessionals and nonprofessionals has resulted along with attempts to develop improved, cost-effective and time-efficient techniques. One such approach has been training parents to use behavior modification techniques to deal with their children's behavior problems, Parent-Child Interaction Training (PCIT) is one program designed to teach parents general techniques for modifying parent-child interaction patterns. This approach attempts to establish mutually-rewarding relationships, while decreasing children's noncompliant and maladaptive behaviors through the use of positive and negative behavioral consequences. Research into the most effective use and application of PCIT has only recently gained momentum, particularly that focusing on the acquisition of the behavior modification skills by the parents. One area of promise may be the utilization of videotape modeling in PCIT. The present study examined the relative effectiveness of traditional live modeling versus videotape modeling of skills taught in PCIT. Mothers were taught PCIT skills through one of the two modes of presentation. Performance before and after treatment was analyzed to determine if there was a difference between presentation modes. Results indicated no difference in effect between the two presentation modes and neither yielded significant effects. However, when presentation form was ignored, PCIT training produced changes. However, methodological compromises preclude any assured inference from these findings and a less equivocal replication is warranted before firm conclusions can be drawn, Nonetheless, the promise of videotape-mediated enhancement of parenting skills remains a viable question.

Thesis monitoring protocol
1991 Forest landscape climate modeling
Everham, E., K. M Wooster, and C.A.S. Hall. 1991. Forest Landscape Climate Modeling M.A. Buford. Proceedings of the 1991 symposium on systems analysis in forest resources: 11-16.
Everham, E.; Wooster, K.M.; Hall, C.A.S. Conference Proceedings simulation
1991 Forest structure before and after Hurricane Hugo at three elevations in the Luquillo Mountains, Puerto Rico N. V. L. Brokaw; Grear, J.S.

Hurricane Hugo struck Puerto Rico on 18 September 1989 and radically altered the canopy structure of forests in the Luquillo Mountains. We measured canopy structure before and after the hurricane in hectare-sized plots of "tabonuco forest" (subtropical wet forest) at 350 m elevation, "colorado forest" (lower montane wet forest) at 750 m, and "cloud forest" (lower montane rain forest) at 1000 m. In all three plots the chief effect of the hurricane was to reduce significantly the vegetation cover in upper height intervals. Foliage profiles (showing percent vegetation cover in height intervals above ground) changed significantly, average maximum canopy height decreased (by as much as 50%), and the amount of low canopy area (vegetation $\leq$2 m high) markedly increased (up to 60-fold) in all three plots. In the colorado forest plot the hurricane caused more damage on ridges than in valleys; whereas, the cloud forest plot sustained equal damage on windward and leeward slopes. Overall, the hurricane altered forest structure so much that forest composition and dynamics could be affected for many years. Local variation in hurricane damage can contribute to forest complexity in the Luquillo Mountains.

Journal Article canopy structure; forest dynamic; forest structure; Hurricane Hugo; species composition
1991 Hurricane damage to a flood plain forest in the Luquillo Mountains of Puerto Rico Frangi, J.L.; Lugo, A.E.

Hurricane Hugo caused low to moderate damage to a flood plain forest that was partially protected by its topographic position. Treefalls and the location of damage suggested N to NW wind direction during the storm. Thirty percent of the trees, or 693 trees/ha, had some damage and 84 percent of the damage was to the canopy Most of the damage to trees was caused by direct wind impact (83%) as opposed to secondary effects (16%). Over 80 percent of the snapped, leaning, and uprooted trees were dicotyledonous. Tree mortality was only 1 percent, and most of the damage to the sierra palm Prestoea montana (R. Grah.) Nichols was loss of leaves. Rapid refoliation, epicormic branching, adventitious root production, resprouting, and regeneration from seed in open areas were observed nine months after the event. Ten percent of the aboveground biomass and 12-16 percent of the nutrient stocks (N, P, K, Ca, Mg) were transferred to the forest floor, mostly in the form of woody biomass and nutrient-rich leaves. Palm leaves were the dominant leaf component of necromass. Instantaneous in situ fine and coarse necromass production was 10 and 9.2 Mg/ha, respectively. Net changes in aboveground mass, N, P, K, Ca, and Mg (in percent of prehurricane value) were 8, 3, 0, 3, 12, and 1, respectively, in spite of a high rate of loss by export. The source of additional mass and nutrients were boles from upland forests that fell into and remained inside the flood plain.

Journal Article hurricane
1991 Hurricane effects on soil organic matter dynamics and forest production in the Luquillo Experimental Forest, Puerto Rico:results of simulation modelling Sanford, R.L.; Parton, W.; Ojima, D.S.; Lodge, D.J. Journal Article soil organic matter
1991 Hurricane Hugo: damage to a tropical rain forest in Puerto Rico Basnet, K.; Likens, G.E.; Scantena, F.N.; Lugo, A.E. Journal Article tropical rain forest
1991 The impact of Hurricane Hugo on forest frogs in Puerto Rico Woolbright, L.L.

Hurricane Hugo caused extensive damaged to the Luquillo Experimental Forest in September 1989. Individually marked Eleutherodactylus coqui were monitored in two study plots from January 1987 through October 1990. Survivorship estimates of adults for the period including the storm were within the normal range from previous years. Juveniles suffered severe reductions, primarily among the smaller size classes. By October 1990 adult population density had increased fourfold over the pre-hurricane levels, although adults were smaller. Juvenile members also appeared to be increasing, but had not yet reached pre-hurricane densities. The rapid increase in density may have resulted from increase in retreat sites and a decrease in invertebrate predators. Auditory censuses suggested that density changes from other species ranged from a 14 percent increase for the relatively common E. hedricki to an 83 percent decrease for the relatively rare E. richmondi.

Journal Article disturbance; Eleutherodactylidae; eleutherodactylus; hurricane; Hurricane Hugo; Luquillo experimental forest; Puerto Rico; tree frog
1991 An introduction to hurricanes in the Caribbean Walker, L.A.; Lodge, D.J.; N. V. L. Brokaw; Waide, R.B. Journal Article Puerto Rico
1991 A landscape simulation model of forest growth for the Luquillo Experimental Forest. Puerto Rico
Everham, E. 1991. A Landscape Simulation Model Of Forest Growth For The Luquillo Experimental Forest. Puerto Rico. In Toward Understanding our environment, Toward Understanding our environment, J. McLeod. San Diego: The Society for Computer Simulation.
Everham, E. Book Chapter Puerto Rico
1991 Mapping and analysis of montane rain forest habitats using LANDSAT TM and elevation data with a Geographic Information System Burns, R.M. Thesis montane rain forest
1991 Nutrient and major element chemistry of Caribbean rain forest streams McDowell, W.H. Journal Article tropical watershed
1991 Physical aspects of Hurricane Hugo in Puerto Rico Scantena, F.N.; Larsen, M.C. Journal Article Puerto Rico
1991 Population dynamics of Manilkara bidentata (A.DC.) Cher. in the Luquillo Experimental Forest, Puerto Rico You, C. Thesis Puerto Rico
1991 Post-Hurricane Hugo increases in atyid shrimp abundances in a Puerto Rican montane st Covich, A.; Crowl, A.T.; Johnson, A.H.; Varza, D.; Certain, D.

We report the first data on changes in tropical stream biota resulting from a major hurricane. Beginning in January 1989, we trapped freshwater shrimp, Atya lanipes, along 1200 m of a montane stream in the Luquillo Experimental Forest, Puerto Rico. Prior to Hurricane Hugo, shrimp densities were greater in the headwaters than at mid- and low elevation. In October 1989, one month after the hurricane, shrimp densities were reduced on average by 50 percent in the headwaters (apparently from washout) and increased by 80 percent at mid-elevation. From December 1989 to May 1990 overall shrimp densities increased rapidly to the highest abundances ever recorded. These densities most likely resulted from increased numbers of shrimp that migrated upstream from riverine pools; and, from increased availability of unusually abundant food resources (decomposing leaves and algae) that increased recruitment of these generalized consumers. Benthic communities in forested, headwater streams are likely to be resilient after intermediate levels of disturbance, because rapid debris-dam formation increases retention of food resources and reduces washout of invertebrate consumers. However, storms generating greater stream flow and/or less wind than Hurricane Hugo could cause extensive, longer-lasting decreases of benthic-dwelling shrimp because of greater washout of both consumers and food supplies.

Journal Article shrimp distribution
1991 The response of Anolis lizards to hurricane-induced habitat changes in a Puerto Rican forest Reagan, P.D.

Fine root dynamics were evaluated at four sites in a subtropical wet forest in Puerto Rico over a period of 13 months following disturbance by Hurricane Hugo in September 1989. Live fine root standing stocks (to a depth of 10 cm) declined to zero over a three month period after the hurricane and fluctuated greatly thereafter. Maximum fine root biomass (49 g/m^2) occured in June 1990. Dead root standing stocks (mean 423 g/m^2) were relatively constant through the study period. Recovery of fine roots following the initial hurricane-related mortality appears to be a slow process, regulated at least initially by environmental factors such as precipitation.

Journal Article reptiles
1991 Summary of ecosystem-level effects of Caribbean hurricanes Lodge, D.J.; McDowell, W.H. Journal Article Review
1991 Summary of response of animal populations to hurricanes in the Caribbean Waide, R.B. Journal Article Puerto Rico
1991 Tree damage and recovery from Hurricane Hugo in Luquillo Experimental Forest, Puerto Rico Walker, L.A. Journal Article tree
1992 Bat reproduction in the Luquillo Experimental Forest of Puerto Rico Gannon, M.R.; Willig, M.R. Journal Article reproductive patterns
1992 Belowground ecology of forests
Publicover, D.A., and D. Vogt. 1992. Belowground Ecology Of Forests. In Yearbook of Science and Technology, Yearbook of Science and Technology, New York: McGraw-Hill, 427-429.
Publicover, D.A.; Vogt, D. Book Chapter soil ecology
1992 Biomass and nutrient accumulation in ten year old bryophyte communities inside a flood plain in the Luquillo Experimental Forest, Puerto Rico Frangi, J.L.; Lugo, A.E.

Ten year old bryophyte communities growing on wooden stakes along a microtopographic gradient in a flood plain forest at 750 m elevation accumulated between 210 and 1400 kg/ha of ash-free biomass and an average of 14.5, 0.8, 5.3, 2.7, 2.7, 18.5, and 22.0 kg/ha of N, P, K, Ca, Mg, Mn, Fe, and Al, respectively. This biomass and nutrient accumulation was in the same order of magnitude as the accumulation of biomass and nutrients in fine litter. Both biomass and nutrient accumulation were greater in communities on stream bank slopes or slopes of tree mounds. Less biomass and nutrient accumulated in depressions with long hydroperiods. Concentration of nutrients (except N), and annual rate of ash-free biomass accumulation (20-140 kg/ha$\cdot$yr) were low in comparison with other bryophyte communities. Bryophyte communities in tropical flood plains appear to be biotic filters of flood waters and help retain nutrients in the terrestrial biota.

Journal Article tropics
1992 Comparison of tropical tree plantations with secondary forests of similar age Lugo, A.E. Journal Article tropical tree plantations
1992 Congeneric species distribution and abundance in a three-dimensional habitat: the rain forest Anoles of Puerto Rico Reagan, P.D. Journal Article Anoles; Puerto Rico; rain forest; rain forest Anoles; three-dimensional habitat
1992 The distribution and abundance of organisms as a consequence of energy balances along multiple environmental gradients Hall, C.A.S.; Stanford, J.A.; Hauer, F.R. Journal Article population ecology
1992 Ecological consequences of root grafting in tabonuco (Dacryodes excelsa) trees in the Luquillo Experimental Forest, Puerto Rico Basnet, K.; Scantena, F.N.; Likens, G.E.; Lugo, A.E. Journal Article unions
1992 The effect of litter, nutrients, and light on seedling populations in the Luquillo Experimental Forest after Hurricane Hugo Guzman, S. Thesis population ecology
1992 Effect of topography on the pattern of trees in tabonuco (Dacryodes excelsa) dominated rain forest of Puerto Rico Basnet, K. Journal Article tree distribution
1992 The effects of small-scale and catastrophic disturbances on carbon and nutrient cycling in a lower montane subtropical wet forest in Puerto Rico Silver, W.L. Thesis Puerto Rico
1992 Epiphytes and climate change research in the Caribbean: a proposal Lugo, A.E.; Scantena, F.N. Journal Article Review
1992 Estudios preliminares sobre comunidades de briofitas en troncos en descomposicion en el bosque subtropical lluvioso de Puerto Rico de Jesus, S. Journal Article wet subtropical forest
1992 An experimental study of the slope stability of the rain forest in Puerto Rico Basnet, K. Journal Article tropical rain forest
1992 A food web for a tropical rain forest: the canopy view from Anolis Dial, R.

The trophic stature of Anolis evermanni and A. stratulus is examined in light of a series of experiments and observations conducted at canopy level in a Caribbean rain forest (Puerto Rico). Trade winds are shown to play an important role as a physical transport process in rain forest canopy in the Caribbean. The supply of flying insects to Anolis communities within the forest canopy is determined by a physical transport process in a manner analogous to the way marine intertidal communities are provisioned by water currents. The result is a one-way predator-prey interaction that may enhance species co-existence. A six-month removal experiment performed at canopy level quantified the predatory role of insectivorous Anolis lizards there. Counts were made of aerial-web spiders, leaf-dwelling arthropods, and flying insects caught in sticky-traps. An index of dispersal ability was measured using cylindrical sticky-traps suspended over forest gaps. Initial densities of arboreal anoles correlated positively and significantly with flying insects caught in sticky-traps, but not with leaf-sampled arthropod abundances. Removal and exclusion of anoles from individual tree crowns of Dacryodes excelsa using trunk collars revealed strong responses in abundances of several arthropod groups, particularly those greater than 2 mm long, not cryptically colored and poorly dispersing. The effect on herbivores cascaded to plants. Prevalence of defoliation was higher in anole-removal crowns than in controls. Percentage of leaflets damaged was positively correlated with leaf-dwelling orthopteran abundance, suggesting a three-trophic-level effect of lizards on plants. The effect of lizards on small predators cascaded to the smallest prey lengths with a weak, statistical significance. The two-species guild, A. evermanni and A. stratulus, is investigated. The high degree of overlap in structural niche, solar climatic niche, limiting prey depression, and the observation of interspecific aggression suggests strong present-day competition between the two anole species. This competition is suggested to result in crown-by-crown competitive exclusion. The biology of a flesh fly (Diptera: Sarcophagidae) that lethally parasitizes anoline hosts is described. The implication of the infection on the occurrence of body spots in A. stratulus is discussed.

Thesis tropical rain forest
1992 A geographically-based ecosystem model and its application to the carbon balance of the Luquillo Forest, Puerto Rico Hall, C.A.S.; Taylor, C.M.; Everham, E. Journal Article watershed modelling
1992 Habitat selection, home range, and population dynamics of Caracolus caracolla in the Luquillo Experimental Forest of Puerto Rico Cary, J.F. Thesis Puerto Rico
1992 Immediate impact of Hurricane Hugo on a Puerto Rican rain forest Walker, L.A.; Voltzow, J.; Ackerman, J.D.; Fernandez, E.; Fetcher, N. Journal Article rain forest
1992 Landslides triggered by Hurricane Hugo in eastern Puerto Rico, September 1989 Larsen, M.C.; de Leon, S. Journal Article Puerto Rico
1992 Lepidoptera outbreaks in response to successional changes after the passage of Hurricane Hugo in Puerto Rico Torres, J.A. Journal Article Puerto Rico
1992 Long-term emergence phenology of Trichoptera from tropical mountain streams of Puerto Rico Masteller, E.C.; Jr, O.S.Flint Conference Proceedings tropical streams
1992 Meshsize as a factor in avian community studies using mist nets Pardieck, K.; Waide, R.B. Journal Article ornithology
1992 Morphometric variation, measurement error, and fluctuating asymmetry in the red fig-eatingbat (Stenoderma rufum) Gannon, M.R.; Willig, M.R.; Willig, M.R. Journal Article Stenoderma
1992 New species of caddisflies from Puerto Rico (Trichoptera)
Jr, O.S. Flint. 1992. New Species Of Caddisflies From Puerto Rico (Trichoptera). Proceedings of the Entomological Society of Washington 94(3): 379-389.
Jr, O.S.Flint Journal Article Trichoptera
1992 A research perspective on disturbance and recovery of a tropical montane forest
Waide, R. B, and A. E Lugo. 1992. A Research Perspective On Disturbance And Recovery Of A Tropical Montane Forest. In Tropical forests in transition: ecology of natural and anthropogenic disturbance processes, Tropical forests in transition: ecology of natural and anthropogenic disturbance processes, J. G Goldammer. Basel, Switzerland: Berkhauser-Verlag, 173-190.
Waide, R.B.; Lugo, A.E. Book Chapter tropical montane forest
1992 Riparian nitrogen dynamics in two eomorphologically distinct tropical rain forest watersheds: nitrous oxide fluxes Bowden, R.D.; McDowell, W.H.; Asbury, C.E.; Finley, A. Journal Article Tropical
1992 Riparian nitrogen dynamics in two geomorphologically distinct tropical rain forest watersheds: subsurface solute patterns McDowell, W.H.; Bowden, R.D.; Asbury, C.E. Journal Article tropical rain forest
1992 The search for carbon sinks in the tropics
Lugo, A. E. 1992. The Search For Carbon Sinks In The Tropics. Water, Air and Soil Pollution (64): 3-9.
Lugo, A.E. Journal Article global carbon
1992 Short-term effects of Hurricane Gilbert on terrestrial bird populations in Jamaica Wunderle, J.M.; Lodge, D.J.; Waide, R.B. Journal Article birds; terrestrial birds
1992 Soil-vegetation relationships in a tabonuco forest community in the Luquillo Mountains of Puerto Rico Johnston, M.H. Journal Article tropical soils
1992 Studies of Neotropical caddisflies, XLVII. Kumanskiella, a new genus of microcaddisflies from Cuba and Puerto Rico Harris, S.C.; Jr, O.S.Flint Journal Article neotrichiini
1992 Tropical forests as sinks of atmospheric carbon
Lugo, A. E, and S. Brown. 1992. Tropical Forests As Sinks Of Atmospheric Carbon. Forest Ecology and Management 54: 239-255.
Lugo, A.E.; Brown, S. Journal Article source sink relationship
1992 Wood densities of tropical tree species
Reyes, G., S. Brown, J. Chapman, and A. E Lugo. 1992. Wood Densities Of Tropical Tree Species. New Orleans, Louisiana: USDA Forest Service, Southern Forest Experiment Station.
Reyes, G.; Brown, S.; Chapman, J.; Lugo, A.E. Report Wood densities
1993 Analysis of leaf and fine root litterfrom a subtropical montane rain forest by pyrolysis-gas chromatography-mass spectrometry Galletti, G.C.; Reeves, J.B.; Bloomfield, J.; Vogt, D.; Vogt, D.

As a preliminary part of a larger study on litter decomposition in tropical forests, pyrolysis—gas chromatography/mass spectrometry, Fourier transform-infrared spectroscopy (FT-IR) and conventional wet chemistry methods were used to determine the composition of tropical leaf and fine root tissue, and the quality of the tissue acting as a substrate for decay. Wet chemistry fiber analysis of Sierra Palm (Prestoea montana) and Tabonuco (Dacryodes excelsa) samples suggested high total lignin contents which were not supported by the other techniques. Results showed a high amount of phenol being produced during the pyrolysis of Sierra Palm, and lower total lignin content than that measured by wet chemistry. Typical FT-IR spectra and pyrograms with peak identification and quantitative data are reported.

Journal Article subtropical montane forest
1993 An annotated list of the flora of the Bisley area, Luquillo Experimental Forest, Puerto Rico, 1987 to 1992 Chinea, J.D.; Beymer, R.J.; Rivera, C.; de Jesus, S.; Scantena, F.N. Report flora list
1993 The aroids of Luquillo forest and their temperature cycles during flowering Whitehill, J. Thesis temperature cycles
1993 Belowground responses a sindicators of environmental change Vogt, D.; Publicover, D.A.; Bloomfield, J.; Pérez-Jiménez, J.R.; Vogt, D.; Silver, W.L. Journal Article turnover
1993 Biomass and nutrient content of the Bisley Experimental Watersheds, Luquillo Experimental Forest, Puerto Rico before and after Hurricane Hugo, 1989 Scantena, F.N.; Silver, W.L.; Siccama, T.G.; Johnson, A.H.; de Leon, S. Journal Article watersheds
1993 Catastrophic and background disturbance of tropical ecosystems at the Luquillo Experimental Forest Lugo, A.E.; Waide, R.B. Journal Article tropical forest
1993 Comparison of tropical and temperate emergence phenology of aquatic insects from Puerto Rico and Pennsylvania Masteller, E.C. Journal Article stream macroinvertebrates
1993 Composition and phenology of Ephemeroptera from a tropical stream at El Verde, Puerto Rico Pescador, M.L.; Masteller, E.C.; Buzby, K.M. Journal Article mayflies diversity
1993 Composition and temporal abundance of aquatic insect emergence from a tropical rainforest stream, Quebrada Prieta, at El Verde, Puerto Rico. Introduction Masteller, E.C.; Buzby, K.M. Journal Article stream macroinvertebrates
1993 Composition and temporal abundance of Chironomidae emergence from a tropical stream at El Verde, Puerto Rico Ferrington, L.C.; Buzby, K.M.; Masteller, E.C.

Emergence composition and temporal abundance of Chironomidae from Quebrada Prieta, a second-order, high-gradient mountain stream near El Verde in the Luquillo Experimental Forest of Puerto Rico, was determined by regular emergence trapping from February 1990 through January 1991. Thirty taxa were collected, with Chironomini being most species rich (11 taxa), followed by Orthocladiinae (9), Tanypodinae (6) and Tanytarsini (4). Chironomini also dominated numerically, comprising 49% of total emergence, followed by Tanypodinae (26%), Orthocladiinae (13%) and Tanytarsini (12%). Chironomini were proportionately most abundant during February (70% of monthly emergence), March (63%) and January (56%), and least abundant during August (27%), corresponding to months of minimum and maximum rainfall, respectively. This pattern is in contrast to the emergence pattern of Chironomini in mid-latitudes, where they are proportionately more abundant during summer months. Two species each of Xestochironomus and Stenochironomus, whose larvae are typically xylophagous, were the most common Chironomini (45% of total annual emergence), suggesting that woody debris is an important food basis for the stream Chironomidae. Cricotopus (grazing larvae) and Rheotanytarsus (filter-feeding larvae) constituted less than 5% and 0.1% of total emergence, respectively. Other common genera were Larsia, Labrundinia, Pentaneura, Limnophyes, Tanytarsus and Polypedilum. All taxa that were common displayed multiple emergence peaks or emerged continuously throughout the study period.

Journal Article tanytarsini
1993 Composition and temporal abundance of moth flies (Diptera, Psychodidae) from a tropical rain forest stream at El Verde, Puerto Rico Wagner, R.H.; Masteller, E.C. Journal Article tropical rain forest
1993 Controls of environmental factors on pattern of montane rain forest in Puerto Rico Basnet, K. Journal Article tropical rain forests
1993 Decay rate and substrate quality of fine roots and foliage of two tropical tree species in the Luquillo Experimental Forest, Puerto Rico Bloomfield, J.; Vogt, D.; Vogt, D. Journal Article tropical montane rain forest
1993 Distribution of malaria in Anolis lizards of the Luquillo Forest, Puerto Rico Schall, J.J.; Vogt, D. Journal Article tropics
1993 Efectos del huracan Hugo sobre plantaciones y bosques secundarios pareados en el Bosque Experimental de Luquillo, Puerto Rico Rodriquez-Pedraza, C.D. Thesis secondary forest
1993 Effects of age, sex, prior experience, and intraspecific food variation on diet composition of a tropical folivore (Phasmatodea: Phasmatidae) Sandlin, E.A.; Willig, M.R. Journal Article nutrient constraints
1993 Effects of Hurricane Hugo on a population of the termite Nasutitermes costal is in the Luquillo Experimental Forest in Puerto Rico McMahan, E.A.; Blanton, C.M. Journal Article termite ecology
1993 Effects of omnivorous shrimp in a montane tropical stream: sediment removal, disturbance of sessile invertebrates and enhancement of under story algal biomass Pringle, C.M.; Blake, G.A.; Covich, A.; Buzby, K.M.; Finley, A. Journal Article Tropical stream
1993 Effects of tree fall gaps on the density of land snails in the Luquillo Experimental Forest of Puerto Rico Alvarez, J.; Willig, M.R. Journal Article treefalls
1993 Emergence composition and phenology of Tipulidae (Diptera) from a tropical rainforest stream Gelhaus, J.K.; Masteller, E.C.; Buzby, K.M. Journal Article tupulide
1993 Emergence composition and phenology of Trichoptera from a tropical rainforest stream at El Verde, Puerto Rico Jr, O.S.Flint; Masteller, E.C.

An emergence trap operated over a small mountain stream in Puerto Rico collected 2561 specimens of Trichoptera in a 12 month period. Sixteen species were collected, with a single species, Cariboptila orophila, comprising 78.2% of the emergence. Females made up 58% of the catch, although this varied somewhat depending on the taxon. There was a pronounced minimum in the emergence pattern in June and July with a secondary drop in November. The average annual rainfall pattern offers no clear correlation with emergence, but the November drop might have been correlated with a sharp peak in rainfall in October of 1990. There does seem to be some seasonality in flight periods of some species, but the more abundant species were present year round.

Journal Article Trichoptera
1993 Emergence phenology of Empididae, Ceratopogonidae, and simulidae (Diptera) from a tropical rainforest stream at El Verde, Puerto Rico Masteller, E.C.; Buzby, K.M. Journal Article stream macroinvertebrates
1993 Fine root dynamics following single and multiple disturbances in a subtropical wet forest ecosystem Silver, W.L.; Vogt, D. Journal Article tropics
1993 Fruit fall in the Luquillo Experimental Forest, Puerto Rico Lugo, A.E.; Frangi, J.L. Journal Article tropical trees
1993 The management of Luquillo cloud forest ecosystems: irreversible decisions in a non-substitutable ecosystem Scantena, F.N. Conference Proceedings non-sustainable ecosystem
1993 Morphology and sedimentation in Caribbean montane streams:examples from Jamaica and Puerto Rico Ahmad, R.; Scantena, F.N.; Gupta, A.

This paper presents a summary description of the morphology, sedimentation, and behaviour of the montane streams of eastern Jamaica and eastern Puerto Rico. The area is located within a 200 km wide seismically active zone of Neogene left-lateral strike-slip deformation which defines the plate boundary between the Caribbean and North American Plates. Tropical storms, occasionally strengthening up to hurricane force, affect the region periodically. This is an area of steep, mass-movement-scarred hillslopes which supply a large amount of coarse sediment to the rivers. From the description presented, we have constructed a model for the rivers of this region controlled by both neotectonics and periodic large floods. The drainage density is low with a near-rectangular stream network. The gradients are steep with boulder accumulations in the channels, their location at times related to the presence of large past landslides on hillslopes. Narrow, steep and confined channels occur in the mountains, but in wider sections and lower down near coastal plains, flood depositional forms appear in coarse valley alluvium. Small-scale deviations from the general pattern occur locally, controlled by variations in lithology, neotectonism, seasonality in flow, etc. This model for Caribbean montane streams differs considerably from the standard descriptions of alluvial rivers for which a number of detailed studies are available.

Journal Article streams sedimentology
1993 Movement and home range of the Puerto Rican Screech-Owl (Otus nudipes) in the Luquillo Experimental Forest Gannon, M.R.; Pardieck, K.; Willig, M.R.; Waide, R.B.

Home range and site fidelity of the Puerto Rican Screech-Owl (Otus nudipes) were examined in the Luquillo Experimental Forest of Puerto Rico. Two individuals, one adult and one juvenile, were radio-tagged and tracked for several weeks during the rainy season in the summer of 1989. Owls exhibited a persistent tenacity for one relatively small foraging area, in which they also roosted during the day. Although the home ranges of both individuals were located in close proximity to each other, little overlap occurred. These owls had home ranges considerably smaller (by a factor of 10 or more) when compared to other similarly sized owls in temperate zones.

Journal Article tropic screech-owls
1993 Nutrient accumulation during succession in subtropical lower montane wet forests, Puerto Rico Zarin, D.J. Thesis subtropical montane forests
1993 Nutrient cycling by fungi wet tropical forests
Lodge, D. J. 1993. Nutrient Cycling By Fungi Wet Tropical Forests. In Aspects of tropical mycology, Aspects of tropical mycology, S. Isaac, Frankland, J. C, Watling, R., and Whalley, A. JS. Cambridge, England: Cambridge University Press, 37-57.
Lodge, D.J. Book Chapter tropical forests
1993 Nutrient dynamics and the influence of substrate quality on the decomposition of leaves and fine roots of selected tree species in a lower montane tropical rain forest in Puerto Rico Bloomfield, J. Thesis Puerto Rico
1993 Orchid-phorophyte relationship in a forest watershed in Puerto Rico Migenis, L.E.; Ackerman, J.D. Journal Article rain forest
1993 Post hurricane seed rain dynamics in Puerto Rico Walker, L.A.; Neris, L.E. Journal Article tropical forest
1993 The role of mycorrhizae in the nutrient absorptive strategy of important landslide colonizers Calderon, F. Thesis nutrient absorptive
1993 Seedling growth and mortality of four shade-tolerant canopy tree species in the rain forest of Puerto Rico following Hurricane Hugo Petty, W.H. Thesis seedlings
1993 Spatial heterogeneity of seed rain, seed pool, and vegetative cover on two Monteverde landslides, Costa Rica Myster, R.W. Journal Article regeneration
1993 Structural and taxonomic components of habitat selection in the Neotropical folivore, Lamponius portoricensis (Phasmatodea: Phasmatidae) Willig, M.R.; Sandlin, E.A.; Gannon, M.R. Journal Article understory
1993 Tropical forest uses
Lugo, A. E. 1993. Tropical Forest Uses. In Developmentor destruction: the conversion of tropical forest to pasture in Latin America, Developmentor destruction: the conversion of tropical forest to pasture in Latin America, T. E Downing, Hetcht, S. B, Pearson, H. A, and Garcia-Downing, C. San Francisco: Westview Press, 117-132.
Lugo, A.E. Book Chapter forest international policies
1993 Rainfall-threshold conditions for landslides in a humid-tropical system, Puerto Rico Larsen, M.C.; Simon, A. Journal Article
1993 Research plan for the investigation of water, energy, and biogeochemical budgets in the Luquillo mountains, Puerto Rico Larsen, M.C.; Collar, P.D.; Stallard, R.F. Report
1994 Benthic prey avoidance behaviors in response to decapod predators:temperate and tropical comparisons Covich, A.; Crowl, A.T.; Alexander, J.E.; Vaughn, C.C. Journal Article Benthic organism; decapod predators; decapods; ecosystems comparisons
1994 Determining the ecosystem attributes of plant diversity in a subtropical forest, Puerto Rico Ahearn, L. Thesis Puerto Rico
1994 Ecologic-economic value analysis multiple-uses in the Luquillo Experimental Forest, Puerto Rico Doherty, S.J.; Scantena, F.N.; Odum, H.T. Conference Proceedings Puerto Rico
1994 The effect of human activity on the structure and composition of a tropical forest in Puerto Rico Garcia-Montiel, D.; Scantena, F.N. Journal Article impacted forest dynamic
1994 Effects of fern thickets on woodland development on landslides in Puerto Rico Walker, L.A. Journal Article Tabebuia heterophylla
1994 The effects of Hurricane Hugo on bats of the Luquillo Experimental Forest of Puerto Rico Gannon, M.R.; Willig, M.R.

Natural disturbances can have large effects on ecosystem structure and function depending on their scale, intensity, and frequency. On 18 September 1989 Hurricane Hugo struck Puerto Rico, with the eye of the hurricane passing within 10 km of the Luquillo Experimental Forest. This provided a rare opportunity to evaluate the effects of an infrequent but large scale and high intensity disturbance on tropical bat species. Data on demographic parameters of three common phyllostomid bats (Artibeus jamaicensis, Stenodema rufum, and Monophyllus redmani) were examined for three years prior and three years after the hurricane. Population levels as estimated by captures per net hour of all three species were affected by Hurricane Hugo. Populations of A. janzaicensis and M, redmani returned to predisturbance levels within two years. In contrast, population levels of S, rujum declined to about 30 percent of prehurricane levels and have not recovered after three years. Moreover, telemetry data indicate that foraging and home range size expanded to encompass an area approximately five times larger than its prehurricane size. The cost of foraging, in terms of time and energy, may be considerably elevated over prehurricane scenarios. In fact, a significant change in the age structure of the population (juvenile individuals have been absent from the population since Hurricane Hugo) as well as significant decline in the percent of reproductively active females indicate a failure to reproduce in the posthurricane environment.

Journal Article rain forest
1994 Emergency Evaluation of the Luquillo Experimental Forest, Puerto Rico
Doherty, S.J., F. N Scantena, and H.T. Odum. 1994. Emergency Evaluation Of The Luquillo Experimental Forest, Puerto Rico. Gainesville, Florida: Center for Environmental Policy, Environmental Engineering Sciences, University of Florida.
Doherty, S.J.; Scantena, F.N.; Odum, H.T. Report dasonomy; Management; Puerto Rico
1994 Export of carbon, nitrogen, and major ions from three tropical montane watersheds McDowell, W.H.; Asbury, C.E. Journal Article watersheds
1994 Hurricane impacts to tropical and temperate forest landscapes Boose, E.; Foster, D.; Fluet, M. Journal Article wind damage
1994 The importance of nutrient pulses in tropical forests Lodge, D.J.; McDowell, W.H.; McSwiney, C.P. Journal Article riview
1994 Invertebrate community structure and herbivory in a tropical rainforest canopy in Puerto Rico following Hurricane Hugo Schowalter, T.D. Journal Article species diversity
1994 Is nutrient availability related to plant nutrient use in humid tropical forests? Silver, W.L. Journal Article soil phosphorus
1994 Island hydrology: Puerto Rico and the U.S. Virgin Islands. National Geographic Research; Exploration Zack, J.C.; Larsen, M.C. Journal Article U.S. Virgin Islands
1994 Landslide insects show small differences between an island (Puerto Rico) and the mainland (Costa Rica) Myster, R.W. Journal Article watersheds
1994 Latitudinal patterns in leaf litter breakdown: is temperature really important? Irons, J.G.; Oswood, M.W.; Stout, R.J.; Pringle, C.M. Journal Article stream food web
1994 Mapping a long-term ecological research area in Puerto Rico Mount, H.; Lynn, W.; Vick, R.; Dubee, B.; Zou, X.M. Journal Article Soils
1994 Non-visual cues in benthic predator-preysystems: introduction to a symposium
Crowl, A.T., and J.M. Culp. 1994. Non-Visual Cues In Benthic Predator-Preysystems: Introduction To A Symposium. Journal of the North American Benthological Society 13: 266-267.
Crowl, A.T.; Culp, J.M. Journal Article NABS
1994 Non-visual cues in freshwater benthios and plankton
Dodson, S. I, A.T. Crowl, B.L. Peckarsky, L.AB. Katz, A. Covich, and J.M. Culp. 1994. Non-Visual Cues In Freshwater Benthios And Plankton. Journal of the North American Benthological Society 13: 268-282.
Dodson, S.I.; Crowl, A.T.; Peckarsky, B.L.; Katz, L.A.B.; Covich, A.; Culp, J.M. Journal Article amphibians; anti-predation morphology; behavior; chemical signals; insects; mechanical signals; molluscs; zooplakton
1994 Notes on the absolute abundance of canopy anoles, anolis cuvieri, a. evermanni(Lacertilia: Polychridae) in the Luquillo Forest, Puerto Rico. Caribbean Dial, R.; Roughgarden, J. Journal Article Caribbean; herpetology; Puerto Rico
1994 Nutrient availability in a montane wet tropical forest: spatial patterns and methodological considerations Silver, W.L.; Scantena, F.N.; Johnson, A.H.; Siccama, T.G.; de Leon, S. Journal Article Ecology; tropical forest; tropical forest ecology
1994 Preservation of primary forests in the Luquillo Mountains, Puerto Rico Lugo, A.E. Journal Article usfs
1994 Quantitative effects of atyid shrimp(Decapoda: Atyidae) on the depositional environment in a tropical stream: use of electricity for experimental exclusion. Canadian Journal of Fisheries and Aquatic Pringle, C.M.; Blake, G.A.

Effects of biotic (shrimp) and abiotic (discharge) factors on the depositional environment were quantified in a montane stream in Puerto Rico. Electricity was used experimentally to exclude large (approximately >1 cm in length) biota without artificially increasing sedimentation as in cage enclosure/exdosure experiments in stream systems. Shrimp (>1 cm in length) were excluded from rock substrata by semicircular fences hooked up to battery-powered fence chargers which emitted continuous pulses of electricity. Unelectrified control substrata had natural high densities of atyid shrimp. Significantly greater masses of total sediment, fine and large organic particles, and algal biovolume occurred in shrimp exclusion treatments relative to controls. Shrimp exclusion treatments experienced slow and steady accumulation of sediments under base flow conditions and a large stepwise increase in sediment weight following a storm. No measurable sediment accrued in the presence of natural densities of shrimp under base flow conditions. Shrimp rapidly removed sediments that accrued during the storm (440–620 g∙m2 dry mass−1), decreasing sediment mass in control treatments to near prestorm levels (5–13 g∙m2 dry mass−1) within 30 h. Atyid shrimp can significantly affect the accumulation of organic and inorganic materials on rock substrata in stream pools between high-discharge events.

Journal Article Tropical stream
1994 Records of bat ectoparasites from the Luquillo Experimental Forest of Puerto Rico Gannon, M.R.; Willig, M.R.

During the course of ecological research in the Luquillo Experimental Forest (LEF)of Puerto Rico, we collected ectoparasites from seven species of bats: Artibeus jamaicensis, Brachyphylla cavernarum intermedia, Eptesicus fuscus wetmorei, Erophylla sezekorni sezekorni, Monophyllus redmani portoricensis, Pteronotus parmellii portoricensis, and Stenoderma rufum darioi. Herein, we report ectoparasites infesting these bats and provide comments on host-parasite associations. Bats were captured in the mist of nest from various locations withing the LEF during the dry (March) and rainy (June-August) seasons of 1988 and 1989. Withing 20 minutes of capture, wing an tale membranes, pelage, ears, and faces were examined for the presence of anthropods. Ectoparasites were removed and place in vials containing 70% ethyl alcohol; a separate vial stored all ectoparasites from each bat. Hosts were then banded and subsequently released.

Journal Article tropical bats
1994 Responses of a fresh water shrimp to chemical and tactile stimuli from a large decapod predator Crowl, A.T.; Covich, A.

Montane, tropical streams in Puerto Rico are dominated by decapod crustaceans. The most ubiquitous freshwater shrimp, with a distribution ranging from mangrove swamps to the highest-elevation pools, is Atya lanipes, a scraper/filterer. A large predatory shrimp, Macrobrachium carcinus, is much less abundant but dominates the top of the stream foodweb. As part of our long-term ecological research, we have observed a general negative relationship between Atya abundance and the presence of the large predatory shrimp. In a series of laboratory and field experiments, we showed that this relationship was primarily due to avoidance responses by Atya to the predator species. Furthermore, our experiments showed that both chemical and mechanical/tactile cues of predator presence determined the among-pool distribution of Atya within streams. Although chemical cues alone elicited a relatively weak response, the combination of chemical and tactile cues resulted in very strong movement responses. If the prey were confined to pools with predatory shrimp, the prey significantly decreased their overall movement and spent substantially more time in crevices. If given the opportunity, prey shrimp emigrated out of areas that had predatory decapods.

Journal Article tactile cues
1994 Responses of tree species to hurricane winds in subtropical wet forest in Puerto RIco: implications for tropical tree life histories Zimmerman, J.K.; Everham, E.; Waide, R.B.; Lodge, D.J.; Taylor, C.M.; N. V. L. Brokaw Journal Article wind damage
1994 Seedling recruitment and growth on hurricane-disturbed plots in a subtropical wet forest in Puerto Rico: the role of abiotic influences in the regeneration niche Cammack, S.E. Thesis abiotic factors; hurricane; Puerto Rico; Seedling recruitment; subtropical wet forest
1994 Solute deposition from cloud water to the canopy of a Puerto Rican montane forest Asbury, C.E.; McDowell, W.H.; Trinidad-Pizarro, R.; Berrios, S.

Deposition of cloud water and dissolved solutes onto vegetation was studied by sampling clouds, throughfall and stemflow during 12 cloud-only events at Pico Del Este, a tropical cloud forest in the Luquillo Mountains of Puerto Rico. Liquid water content of the sampled clouds was low (0.016 g m−3), but deposition of water (1.3 mm d−1)was comparable to other sites, apparently due to efficient capture of clouds by epiphyte-laden vegetation. Elemental deposition by cloud water was similar to that in other, more polluted sites, but was only 8–30% of total deposition (cloud-only plus rain) due to the high rainfall at the site (approximately 5 m). Na and CI from marine aerosols dominated cloud chemistry, with concentrations of 400 μeqδ−1. Sulfate and nitrate concentrations were 180 and 60 μedδ−1, respectively. After passage through the canopy, concentrations of base cations in deposited cloud water increased, and concentrations of nitrogen decreased.

Journal Article tropics
1994 Three host-specific Xylaria species Laessøe, T.; Lodge, D.J. Journal Article Xylaria
1994 Using remotely sensed data and GIS to map hurricane damage in tropical forests Woolbright, L.L. Report tropical forests
1994 The value of water in a Puerto Rican forest Scantena, F.N.; Doherty, S.J.; Odum, H.T. Conference Proceedings Puerto Rican forest
1994 Functional diversity of microbial communities: A quantitative approach Zack, J.C.; Willig, M.R.; Moorhead, D.L.; Wildman, H.G.

Evaluating the biodiversity of microbial communities remains an elusive task because of taxonomic and methodological difficulties. An alternative approach is to examine components of biodiversity for which there exists a reasonable chance of detecting patterns that are biologically meaningful. One such alternative is functional diversity. We propose a procedure based on the Biolog identification system to quickly, effectively, and inexpensively assess aspects of the functional diversity of microbial communities. The numbers and types of substrates utilized by bacterial communities, as well as the levels of activities on various substrates and patterns of temporal development, constitute an information-rich data set from which to assess functional diversity. Data from six plant communities (black grama grassland. Sporobolus grassland, creosotebush bajada, herbaceous bajada, mesquite-playa fringe, and playa grassland) located along an elevational and moisture gradient at the Jornada Long-Term Ecological Research site in the northern Chihuahuan Desert, are analyzed to illustrate the procedure and its relevance to biodiversity. Our analyses demonstrate that the Biolog system can detect considerable variation in the ability of microbial communities to metabolize different carbon compounds. Variation in substrate use was compartmentalized differently along the moisture gradient. Differences in functional diversity were dependent upon the class of carbon sources (guild-specific results). A multifaceted approach to biodiversity that comprises both functional and taxonomic perspectives represents fertile ground for future research endeavors.

Journal Article
1995 Base saturation, nutrient cation,and organic matter increases during early pedogenesis onlandslide scarsin the Luquillo Experimental Forest, Puerto Rico Zarin, D.J.; Johnson, A.H. Journal Article Puerto Rico
1995 Canopy invertebrate community response to disturbance and consequences of herbivory in temperate and tropical forests Schowalter, T.D. Journal Article tropical forests
1995 Carbon isotope characterization of vegetation and soil organic matter in subtropical forests in Luquillo, Puerto Rico von Fischer, J.C.; Tieszen, L.L. Journal Article soil organic matter
1995 Climate driven population fluctuations in rain forest frogs Stewart, M.M. Journal Article rain forest frogs
1995 A comparison of methods for quantifying catastrophic wind damage to forests
Everham, E. 1995. A Comparison Of Methods For Quantifying Catastrophic Wind Damage To Forests. In Wind and wind-related damage to trees, Wind and wind-related damage to trees, M.P. Coutts and Grace, J. Cambridge, U.K: Cambridge University Press, 340-357.
Everham, E.

Catastrophic wind events impact forests over the entire globe. Although recent examples of hurricanes in the Caribbean have led to intense examination of the impacts on, and recovery of, forests, these research efforts have largely been in isolation. Little has been done to compare the impacts of storms of varying intensity on different ecosystems. Therefore, we can not as yet fit catastrophic wind events into a general model of forest disturbance and recovery. Papers examining the impacts of 26 different wind events (cyclonic storms, tornadoes and gales) on 27 different forests are reviewed. Hurricane damage is measured as numbers or percentage: stem damage, canopy damage, biomass or stand volume loss, or mortality. The populations sampled varied from minimum stem size of 2 cm to 20 cm in diameter. Sampling methodology included small circular plots, transects, large gridded plots and remote sensing of the landscape. Plots were established 10 days to 3 years after the wind event. The implications of these different quantification systems are examined using data from a large gridded plot established in the Luquillo Mountains of Puerto Rico to study the impacts of Hurricane Hugo. Intensity of disturbance, measured as percentages of different damage types, varied depending on the minimum stem size used in the analysis. Damage to individual species also varied depending on the variable used to quantify it. Clearly, a standard measure of wind damage is needed to facilitate comparisons of the impacts of different storms on different forests. I suggest a damage measure that includes both mortality and structural loss as measured by decrease in basal area.

Book Chapter wind effect
1995 Comprehensive bibliography on Tropical montane cloud forest bibliography
Watt, F., R. Beymer, F. N Scantena, W. L Silver, P.L. Weaver, and L.S Hamilton. 1995. Comprehensive Bibliography On Tropical Montane Cloud Forest Bibliography. In Tropical Montane Cloud Forests, Tropical Montane Cloud Forests, L.S Hamilton, Scantena, F. N, and Juvik, J.O. Ecological Studies 110, Springer Verlag, 247-259.
Watt, F.; Beymer, R.; Scantena, F.N.; Silver, W.L.; Weaver, P.L.; Hamilton, L.S. Book Chapter tropical montane cloud forest
1995 Denudation rates determined from the accumulation of in situ produced10Be in the Luquillo Experimental Forest, Puerto Rico Brown, E.T.; Stallard, R.F.; Larsen, M.C.; Raiseck, G.M.; Yiou, F. Journal Article Puerto Rico
1995 The distribution of biodiversity Global Biodiversity Assessment Ricklefs, R.; Kalin-Arroyo, M.T.; Latham, R.E.; Lewinsohn, T.M.; Lodge, D.J.; Crowe, T.; Platnick, N.I.; Wright, S.J. Book Chapter species distribution
1995 Diversity of litter agarics at Cuyabeno, Ecuador: Calibrating sampling efforts in tropical rainforest Lodge, D.J.; Cantrell, S.A. Journal Article spatial patterns
1995 Dynamics of forest floor and soil organic matter accumulation in boreal, temperate, and tropical forests Vogt, D.; Brown, S.; Tilley, J.P.; Edmonds, J.; Silver, W.L.; Siccama, T.G. Journal Article tropical forests
1995 Ecology of ectoparasites from tropical bats
Gannon, M.R., and M. R Willig. 1995. Ecology Of Ectoparasites From Tropical Bats. Environmental Entomology 24: 1495-1503.
Gannon, M.R.; Willig, M.R.

Incidence,prevalence,and densityof ectoparasites are reported for 3 species of tropical bats, Stenoderma rufum Demarest,Artibeus jamaicensis Leach, Monophyllus redmani Leach, from the tabonuco forest of Puerto Rico. In addition,patterns of ectoparasite associations were examined with respect to several host characteristics including age and sex, as well as with respect to season.Levels of ectoparasite infestation differed because of host age, but not sex,with juveniles harboring higher numbers than adults. No ectoparasite attribute differed with season. Significantly different assemblages of parasites occurred on adult male, adult female, and juvenile A. jamaicensis. Moreover,S. rufum, A. jamaicensis, and M. redmani each have a significantly different ectoparasite assemblage.

Journal Article Puerto Rico
1995 Ecosystem-level properties of the Luquillo Experimental Forest with emphasis on the tabonuco forest
Lugo, A. E, and F. N Scantena. 1995. Ecosystem-Level Properties Of The Luquillo Experimental Forest With Emphasis On The Tabonuco Forest. In Tropical forests:management and ecology, Tropical forests:management and ecology, A. E Lugo and Lowe, C. New York: Springer Verlag, 59-108.
Lugo, A.E.; Scantena, F.N. Book Chapter tropical forest structure
1995 Effects of dinitrogen-fixing trees on phosphorus biogeochemical cycling in contrasting forests Zou, X.M.; Binkley, D.; Caldwell, B.A. Journal Article Phosphorus
1995 Effects of land management and a recent hurricane onforest structureand composition in the Luquillo Experimental Forest, Puerto Rico Zimmerman, J.K.; Aide, T.M.; Rosario, M.; Serrano, M.I.; Herrera, L. Journal Article tropics
1995 EMERGY evaluations of and limits to forest production Doherty, S.J.

To replace the nonrenewable sources of fuel and electricity as their availability declines, research continues for renewable alternatives. One of the main possibilities is solar-based, organic biomass from agriculture forestry. Major theoretical and practical questions include: 1) what are the best possible net yields from biomass; 2) are there biophysical limits to biomass production; and 3) how is time related to net resource yield? In this dissertation, energy systems methods are used to evaluate production and multiple-use of a wide range of agroforest systems under different management schedules from temperate and tropical latitudes. Net emergy measures are used to compare biomass fuels with current alternatives in the generation of heat and electricity. Energy-based meassures are compared with market values for forest profucts. An effort is made to determine the thermodynamic maximum production of biomass. By considering full cycles of growth, harvest and regrowth, net yields are related to the rotation period. Computer simulation is used to relate inputs, cycle time, and yield. The discussion considers the implications of biomass limits for the world reforestation, human carrying capacity, and global environmental-energy policy. Forest systems worldwide are increasingly being reorganized by human interactions. Old growth forests are cleared and replaced with managed old ones; silvicultural practices are reducing the turnover time of forest biomass; forests are often burned or are replaced by some other land-use. Following a century of forests exploitation, now global in scale, new and old systems of utilization are needed that are both productive and sustainable. Further, as the availability of fossil fuels decreases, the controversy increases over what is the maximum sustainable conversion of biomass and fuels from renewable solar energy. Recognition and quantification of the full range of values forests provide, including those outside the market economy, are needed in order to determine best uses of forests ecosystems worldwide. Issues such as these require new and comprehensive assessments if scientists, land managers and ultimately policy makers are to make sound decisions regarding our forest resources and their roles in future questions of energy supply and global processes.

Thesis EMERGY; forest production; systemdinamics
1995 Experimental removal of insectivores from rain forest canopy: direct and indirect effects Dial, R.; Roughgarden, J.

This study considered the effects of insectivorous Anolis lizards on a large, complex food web of arthropods and associated herbivory in a tropical rain forest canopy. We excluded Anolis lizards for 6 mo from 20—30 m high tree crowns in Puerto Rican rain forest. Simultaneous with lizard exclusion, we sampled orb spiders, airborne arthropods, and leaf arthropods in lizard removal crowns and in controls. We also sampled herbivory at the end of the experiment. Lizard removal had strong, statistically significant, positive effects on arthropods >2 mm in length and weak negative effects on arthropods <2 mm. Parameters of arthropod body size distributions differed between removals and controls for leaf arthropods, but not for airborne arthropods. Among arthropod taxa >2 mm, both predatory, i.e., orb spiders and parasitic Hymenoptera, and nonpredatory forms, i.e. Diptera, Coleoptera, Orthoptera, and Blattaria, showed strong significant and positive responses to lizard removal. Large Psocoptera, Homoptera, leaf spiders, and ants did not show significant overall responses to lizard removal. Frequency of herbivore damage on new leaves was positively correlated with abundance of Orthoptera and Blattaria. This damage was significantly greater in lizard removal crowns than in controls, indicating an indirect effect of anoles on plants. The indirect effect of lizards on small arthropods through the predatory anthropod pathway appeared weak. Results of lizard removal shown by this study corroborate other lizard removal studies from more xeric, ground—level habitats with simpler food webs in the West Indies, particularly with respect to orb spiders and herbivory. Taken together with the results of similar experiments performed in trophically less complex systems, this experiment suggests that food web size is less important than body size in determining interaction strength between community members.

Journal Article canopy; tropical rain forest; tropical rain forest canopy
1995 Export of nutrients and major ions from Caribbean watersheds
McDowell, W. H, A. E Lugo, and A. James. 1995. Export Of Nutrients And Major Ions From Caribbean Watersheds. Journal of the North American Benthological Society 14: 12-20.
McDowell, W.H.; Lugo, A.E.; James, A. Journal Article tropics
1995 Food web dynamics and applied problems
Crowder, L.B., P.D. Reagan, and D.W. Freckman. 1995. Food Web Dynamics And Applied Problems. In Food Webs: Integration of Patterns and Dynamics, Food Webs: Integration of Patterns and Dynamics, G. A Polis and Winemiller, K.O. New York: Chapman and Hall, 327-336.
Crowder, L.B.; Reagan, P.D.; Freckman, D.W.

One overwhelming conclusion from papers presented in the applications chapters of this book is that humans are a part of natural food webs. In fact, it is our opinion that few if any of the food webs discussed in this book are unimpacted by humans. Given the now global scale effects of the human population on atmospheric processes and their biological impacts (Kareiva et al., 1993), it is naive to speak of natural food webs unimpacted by man. Fragmentation and loss of habitats due to human activities such as waste disposal and agricultural development affect nearly all ecosystems.

Book Chapter stress detection
1995 Forest floor and soil organic matter contents and factors controlling their accumulation in boreal, temperate and tropical forests
Vogt, D., S. Brown, J.P. Tilley, J. Edmonds, W. L Silver, and T.G. Siccama. 1995. Forest Floor And Soil Organic Matter Contents And Factors Controlling Their Accumulation In Boreal, Temperate And Tropical Forests. In Advances in Soil Science - Soil Management and Greenhouse Effect. CRC, Advances in Soil Science - Soil Management and Greenhouse Effect. CRC, R. Lal, Kimble, J., Levine, E., and Stewart, M.M. Boca Raton: Lewis Publishers, 159-178.
Vogt, D.; Brown, S.; Tilley, J.P.; Edmonds, J.; Silver, W.L.; Siccama, T.G. Book Chapter tropical forest
1995 Fungal communities in wet tropical forests: variation in time and space Lodge, D.J.; Cantrell, S.A. Journal Article tropical forests
1995 Geomorphology, disturbance, and the vegetation and soils of two subtropical wet steep land watersheds in Puerto Rico Scantena, F.N.; Lugo, A.E. Journal Article watersheds
1995 Homing behavior of the Puerto Rican frog, Eleutherodactylus coqui Gonser, R.A.; Woolbright, L.L. Journal Article tropical amphibian
1995 Host preference in Camillea verruculospora Lodge, D.J.; Laessøe, T. Journal Article micology
1995 Hurricane disturbance regimes in temperate and tropical forest ecosystems Foster, D.; Boose, E.

We provide an overview of hurricane disturbance regimes in the north-eastern United States and the Caribbean, with a focus on ecological effects on temperate and tropical forests. Hurricanes in tropical regions occur with a higher frequency and reach higher intensity levels than in temperate regions. Slower movement of hurricanes in the tropics exposes forests to longer periods of damaging winds from a broader range of wind directions. At the regional to landscape level we are applying models of hurricane meteorology and topographic exposure to reconstruct wind conditions during historically important storms in order to compare these results to observations of forest damage, and to test two hypotheses: (1) regional gradients of hurricane frequency and intensity result from prevailing hurricane tracks and the configuration of coastlines and mountain rangers and (2) landscape gradients in wind exposure result from the interaction of peak wind directions and local topography. At the community level damage in controlled at windspeed, vegetation structure and composition, and site conditions. Damage patterns strongly control subsequent vegetation dynamics: (1) differential species damages determines the initial compositions and structure of the vegetation , (2) leaf area establishment is controlled by damage type and forest composition, and (3) microenvironmental conditions and resource distribution are determined by the spatial patterns of residual vegetation. Field studies underline the oftentimes low rate of initial mortality following catastrophic storms and the importance of releafing and sprouting in vegetation development. Changes in key ecosystem processes are often slight following even major hurricanes. Studies in Puerto Rico and New England documents that nutrient retention was high, nutrient losses were minimal, soil moisture changed a little, and minor changes in trace in gas fluxes returned rapidly to pre-disturbance levels. Rapid recovery of biotic control of ecosystem processes results from the retention of organic matter on-site and high rates of survival and respouting by tree species.

Book Chapter conservation; Ecology; ecology and conservation; Plant sciences; tropical forests disturbance
1995 The impact of Hurricane Hugo on two common tree snails: A long-term study Secrest, M.F. Thesis Hurricane Hugo; long-term research; tree snails
1995 Key steps to effective watershed characterization Civco, D.L.; Garcia, A.R.; Warner, G.S. Journal Article Hydrology; limnology; watershed characterization; watersheds
1995 The kingdom of epiphytes
Silver, W. L, and A. E Lugo. 1995. The Kingdom Of Epiphytes. In Biosfera 2, Biosfera 2, R. Folch. Barcelona, Spain: Selves tropicals. Enciclopedia Catalana.
Silver, W.L.; Lugo, A.E. Book Chapter orquids
1995 Life in the cloud forest
Silver, W. L, and A. E Lugo. 1995. Life In The Cloud Forest. In Biosfera 2. Selves tropicals, Biosfera 2. Selves tropicals, R. Folch. Barcelona, Spain: Enciclopedia Catalana.
Silver, W.L.; Lugo, A.E. Book Chapter tropical rain forest
1995 Management of tropical biodiversity
Lugo, A. E. 1995. Management Of Tropical Biodiversity. Ecological Applications 5: 956-961.
Lugo, A.E. Journal Article tropics
1995 Nitrogen immobilization by decomposing woody debris and the recovery of tropical wet forest from hurricane damage Zimmerman, J.K.; Pulliam, W.M.; Lodge, D.J.; Quinones, F.; Fetcher, N.; Guzman, S.; Parrotta, J.A.; Asbury, C.E.; Walker, L.A.; Waide, R.B. Journal Article wood descomposition
1995 Nutrient accumulation duringprimary succession in a montane tropical forest, Puerto Rico Zarin, D.J.; Johnson, A.H. Journal Article Puerto Rico
1995 Order I soil survey of the Luquillo Long-Term Ecological Research grid, Puerto Rico
Staff, Soil Survey Soi. 1995. Order I Soil Survey Of The Luquillo Long-Term Ecological Research Grid, Puerto Rico. Lincoln, Nebraska: USDA, Natural Resources Conservation Services.
Staff, S.Survey Soi Report soil ecology
1995 Plant and soil responses tofire on a fern-covered landslide in Puerto Rico Walker, L.A.; Boneta, W. Journal Article tropics
1995 The Puerto Rican Tropical Cloud Forest Symposium: Introduction and Workshop Syntheses Hamilton, L.S.; Juvik, J.O.; Scantena, F.N. Book Chapter Puerto Rico; tropical cloud forest; workshop syntheses
1995 Reconstructing hurricane passages over forests: a tool for understanding multiple-scale responses to disturbance Lugo, A.E. Journal Article tropical forest
1995 Recovery of a tropical forest after gamma irradiation: a 23-year chronicle
Taylor, C.M., S. Silander, R. B Waide, and W.J. Pfeiffer. 1995. Recovery Of A Tropical Forest After Gamma Irradiation: A 23-Year Chronicle. In Tropical forests: management and ecology Ecological Studies, Tropical forests: management and ecology Ecological Studies, A. E Lugo and Lowe, C. SpringerVerlag, 258-285.
Taylor, C.M.; Silander, S.; Waide, R.B.; Pfeiffer, W.J. Book Chapter tropical forest
1995 Relative scales of time and effectiveness of watershed processes in a tropical montane rain forest of Puerto Rico
Scantena, F. N. 1995. Relative Scales Of Time And Effectiveness Of Watershed Processes In A Tropical Montane Rain Forest Of Puerto Rico. In Natural and Anthropogenic Influences in Fluvial Geomophology, Natural and Anthropogenic Influences in Fluvial Geomophology, E. Costa, Miller, A.J., Potter, J.D., and Wilcoch, P. American Geophysical Union press, 103-111.
Scantena, F.N. Book Chapter watershed
1995 Responses of bird populations in a Puerto Rican forest to hurricane Hugo: the first 18 months Wunderle, J.M. Journal Article Hurricane Hugo
1995 The role of elevation and vegetation structure on upland Anolis assemblages in Puerto Rico Garcia-Bermudez, M.A. Thesis Anolis; community assemblages; Puerto Rico; tropical forest; vegetation structure
1995 Roots, nutrients and their relationships to spatial patterns Vogt, D.; Vogt, D.; Asbjornsen, H.; Dahlgren, R.A. Journal Article tropical and temperate forest
1995 Spatial gradient and patch structure in two Puerto Rican landslides Myster, R.W.; Fernandez, E. Journal Article tropical premontane wet forest
1995 Structure, succession soil chemistry of palm forests in the Luquillo Experimental Forest
Lugo, A. E, A. Bokkestijn, and F. N Scantena. 1995. Structure, Succession Soil Chemistry Of Palm Forests In The Luquillo Experimental Forest. In Tropical Forests:management and ecology. Ecological Studies, Tropical Forests:management and ecology. Ecological Studies, A. E Lugo and Lowe, C. Springer Verlag, 142-177.
Lugo, A.E.; Bokkestijn, A.; Scantena, F.N.

Palm brakes growing on steep slopes in the Caribbean are characterized by low species richness, simple community structure, and temporal and spatial variations in community structure. Two Prestoea montana palm forest stands were studied in the Luquillo Experimental Forest over a period of 40 years in order to determine the successional status of the palm brake. The stand with the greater rainfall had fewer tree species, greater species dominance, and lower turnover of species than the stand with less rainfall. Soil structure and chemistry varied widely both vertically and horizontally and could not explain spatial changes in stand structure. Dicotyledonous trees grew larger in the better-drained sites with deeper soils on top of ridges or on steep slopes. Palms dominated swales and waterlogged areas. The combination of geological, climatic (including storms and hurricanes), and geomorphic conditions resulted in a frequently disturbed palm brake environment. The biotic response to such conditions appears to be cyclic successions characterized by a small group of species that replace each other, catastrophic mortalities, rapid growth rates after disturbance, and permanence of the palm forest physiognomy. We suggest that succession in palm brakes follows different directions depending on type of disturbance and site conditions. Site conditions are variable in spite of always being wet and geomorphologically unstable.

Book Chapter soil chemistry
1995 A survey of patterns in fungal diversity Lodge, D.J.; Chapela, I.; Samuels, G.J.; Uecker, F.A.; Desjardin, D.E.; Horak, E.; Miller, A.J.; Hennbert, G.L.; Decock, C.A.; Ammirati, J.; Burdsall, J.H.H.; Kirk, P.M.; Minter, D.W.; Halling, R.; Laessøe, T.; Mueller, G.M.; Oberwinkler, F.; Pegler, D.N.; Spooner, B.M.; Petersen, R.H.; Rogers, J.D.; Ryvarden, L.; Watling, R.; Tunbull, E.; Whalley, A.J.S. Conference Proceedings speciation
1995 Temporal variation and frequency distribution of photosynthetic photon fluxdensities on landslides in Puerto Rico Fernandez, E.; Myster, R.W.

We examined the light environment and its daily variation, both between landslides in different watersheds (the Espiritu Santo watershed contains landslide ES2 and the Rio Blanco watershed contains RB2) and within each landslide on different microhabitats, in the Luquillo Mountaines of Puerto Rico. We found that availability of photosynthetic photon flux density (PFD) peaked in the morning hours on ES2, and that differences between sunny and cloudy days were greater on ES2 than on RB2. For both landslides: (1) these trends were magnitude compared to pen microhabitats (2) forest PFD was reduced by two orders of magnitude compared to open microhabitats and (3) there were reduced PFD levels and heterogeneity with distance from the top of the landslide. In addition, ES2 had more variation in total daily PFD than RB2 and sites on the western side of ES2 received up to 10 times more light than the eastern sites. Usually, low PFD ( lt 100 mu-mol m-2 s-1) was more common than high ( gt 400 mu-mol m-2 s-1) except in the top transect where there was a mix of frequencies and a substantial number of high values.

Journal Article rainforest
1995 Timing of post-hurricane tree mortality in Puerto Rico Walker, L.A. Journal Article tree mortality
1995 Tropical forests: management and ecology
Lugo, A. E, and C. Lowe. 1995. Tropical Forests: Management And Ecology. 1st ed. New York: Springer-Verlag.
Lugo, A.E.; Lowe, C. Book tropical forest management
1995 Tropical forests:their future and our future
Lugo, A. E, and C. Lowe. 1995. Tropical Forests:their Future And Our Future. In Tropical forests: management and ecology, Tropical forests: management and ecology, New York: Springer Verlag, 3-17.
Lugo, A.E.; Lowe, C. Book Chapter tropical forests
1995 Long-term influence of deforestation on tree species composition and litter dynamics of a tropical rain forest in Puerto Rico Zou, X.M.; Zucca, C.; Waide, R.B.; McDowell, W.H.

Understanding the long-term impact of deforestation on ecosystem structure and function of tropical forests may aid in designing future conservation programs to preserve biodiversity and sustain ecosystem productivity. We examined forest structure, tree species composition, litterfall rate, and leaf litter decomposition in a mid-successional forest (MSF) and an adjacent mature tabonuco forest (MTF) in the Luquillo Experimental Forest of Puerto Rico. Whereas the MTF site received limited human disturbance, the MSF site had been cleared for timber production by the beginning of this century and was abandoned after hurricanes struck the Luquillo Mountains in the 1920s and 1930s. We found that the MSF was dominated by successional tree species 50 years after secondary succession, and did not differ in tree basal area and litterfall rate from the MTF. Leaf decomposition rate in the MSF was higher than in the MTF, but this difference was small. Our results show that deforestation has long-term (over 50 years) influence on tree species composition and that recovery of leaf decomposition processes in secondary forest is relatively faster than that of tree species composition.

Journal Article forest recovery; leaf decomposition; litterfall; secondary forest; tabonuco forest
1995 Use of seismic refraction techniques for investigating recent landslides in a tropical rain forest in Puerto Rico
Larsen, M.C. 1995. Use Of Seismic Refraction Techniques For Investigating Recent Landslides In A Tropical Rain Forest In Puerto Rico. In Energy and Mineral Potential of the Central American-Caribbean Region, Energy and Mineral Potential of the Central American-Caribbean Region, A.J. Miller, Escalante, J.A., Reinemund, J.A., and Bergin, M.J. Berlin: Springer-Verlag, 411-414.
Larsen, M.C. Book Chapter
1995 Lizard ecology in the canopy of an island rain forest Reagan, P.D.

Information on animals in rain forest canopies consists almost exclusively of data on mammals and birds(Odum and Pigeon, 1970; Whitmore, 1975; Janzen, 1983; Leigh et al., 1985). Although amphibians, such as Wallace's flying frog (Rhacophorus nigropalmatus) and reptiles such as the paradise tree snake (Chrysopelea pelias) and flying dragon (Draco volans) are known to inhabit the upper parts of tropical rain forest, data on their own populations in the canopy are sparse. The primary reasons for this are the difficulties in observing amphibians and reptiles (which are generally small and relatively immobile) more than a few meterabove ground level, and the challenges of conducting studies within the forest canopy.
The anoline lizards (Anolis spp.) are the most abundant and conspicuous vertebrates that inhabit the terrestial ecosystems on islands in the Caribbean (Moermond, 1979; Williams 1969, 1983). On large islands several species occur syntopically in forest habitas and partition the habitat vertically (Williams, 1972). The habitat and vertical distribution of anoles in Puerto Rico have been investigated by ground-based observers (Rand, 1964; Schoener and Schoener, 1971; Moll, 1978; Lister, 1981), who documented the presence of anoles in the upper reaches of the forest, but provided few insights on their abundance or possible roles in the animal community of the forest canopy. Recent studies in Puerto Rico have produced quantitive information on the abundance and foraging of the anoline lizard that shows that at least in some rain forest, lizards play a significant role in the animal community of the forest canopy.
My work on canopy lizards began as the result of serendipitous observations made shortly after moving to Puerto Rico in 1979/. I had a accepted a position at the Center of Energy and Environment Research of the University of Puerto Rico and made walking surveys through the forest near El Verde Field Station. On such visit, I climbed to the top of a tower that had been erected during the 1960s for irradiation studies. Looking out through the canopy, I noticed several Anolis stratulus on the uppermost branches of nearby trees. Because i could see several individuals from a single point, I reasoned that they must be abundant and, therefore, it might be possible to study them from the tower. This chance of observation of anoles in the canopy led me to investigate the distribution and abundance of A. stratulus and other anole species in three-dimensional habitat of the forest canopy. I began my research with vertical transects to document the vertical distribution and general abundance of anole species in the forest. The results of this study raised additional questions on population density, habitat use and the role of A. stratulus in the forest food web, and started me on a course of research in the forest canopy that I have continued to pursue.
My objective in this chapter is to summarize what is known about anoline lizards that inhabit the canopy of rain forests in Puerto Rico and suggest directions for future research of canopy reptiles. Some of the insights have extended our knowledge of ecosystem structure and function in unexpected directions. The role of the anoles in the forest canopies is not yet known; however, the importance of these lizards in the Puerto Rican rain forest canopies is now established.

Book Chapter canopy; community; invertebrates; tropical forest
1996 The Food web of a tropical rainforest
Reagan, P. D, and R. B Waide. 1996. The Food Web Of A Tropical Rainforest. Chicago, Illinois: University of Chicago Press.
Reagan, P.D.; Waide, R.B. Book food web; Luquillo; Puerto Rico; tropical rain forest
1996 Disturbance influences long-term population patterns in the Puerto Rican frog, Eleutherodactylus coqui (Anura: Leptodactylidae) Woolbright, L.L.

Population estimates from 1987 to 1995 are reported for the terrestrial anuran, Eleutherodactylus coqui, from four long-term study plots in the Luquillo Experimental Forest of northeastern Puerto Rico. The major factor influencing population size during this time was Hurricane Hugo, which deposited much of the canopy onto the forest floor in 1989. This increase in ground-level was in part responsible for a six-fold increase in the number of adult frogs in 1990 and the large increase in the number of juvenile frogs in 1991. Population densities since Hurricane Hugo have been influenced by succession, which continued high densities associated with thickets of Cecropia and Heliconia. Tree-falls, which are similar to hurricanes on a local scale, also were shown to influence population sizes. Years with prolonged dry periods reduced numbers in juvenile frogs, but rain-fall patterns did not explain most population variation. Population levels of invertebrate predators were related to variation in frog numbers.

Journal Article structural habitat treefalls
1996 Introduction: disturbance and Caribbean ecosystems Zimmerman, J.K.; Willig, M.R.; Walker, L.A.; Silver, W.L.

The fifteen articles in this special edition issue describe long-term (> 5 years) responses or perspectives on disturbance in Caribbean ecosystems. Most (11) of the articles describe the responses of Caribbean forests to hurricane disturbance, particularly the effects of Hurricane Hugo on wet forest in Luquillo Experimental Forest (LEF), Puerto Rico. Ten articles discuss, alone or in addition to huricanes, the effects of other types of disturbance including that due to humans, tree-falls,drought, and landslides. In this introductory article we summarize the post-hurricane trajectories of various ecosystem components in the LEF. We also address how responses to other types of disturbance can be brought together to obtain a more thorough understanding of the comparative responses of the Caribbean ecosystems to different disturbances. Finally, we identify those areas of disturbance ecology in the Caribbean that require further investigation.

Journal Article treefalls
1996 An altitudinal comparison of growth and species composition in hurricane-damaged forests in Puerto Rico Walker, L.A.; Zimmerman, J.K.; Lodge, D.J.; Guzman, S. Journal Article tropical forests
1996 Amphibians
Stewart, M.M., and Lawrence L Woolbright. 1996. Amphibians. In The food web of a tropical rainforest, The food web of a tropical rainforest, P.D. Reagan and Waide, R. B. Chicago, Illinois: University of Chicago Press.
Stewart, M.M.; Woolbright, L.L. Book Chapter tropical amphibians
1996 Arboreal arachnids
Pfeiffer, W.J. 1996. Arboreal Arachnids. In The food web of a tropical rain forest, The food web of a tropical rain forest, P.D. Reagan and Waide, R. B. Chicago, Illinois: University of Chicago Press, 247-271.
Pfeiffer, W.J. Book Chapter undestory predators
1996 Arboreal invertebrates
Garrison, R.W., and M. R Willig. 1996. Arboreal Invertebrates. In The food web of a tropical rain forest, The food web of a tropical rain forest, P.D. Reagan and Waide, R. B. Chicago, Illinois: University of Chicago Press, 183-271.
Garrison, R.W.; Willig, M.R. Book Chapter tropical invertebrates density
1996 At what temporal scales does disturbance affect below ground nutrient pools? Silver, W.L.; Scantena, F.N.; Johnson, A.H.; Siccama, T.G.; Watt, F. Journal Article Forest floor; harvesting; hurricane; nutrient availability; root biomass; soil organic matter; tropical forest
1996 Atyid shrimps (Decapoda: Atyidae)influence spatial heterogeneity of algal communities over different scales in tropical montane streams, Puerto Rico Pringle, C.M. Journal Article stream ecology
1996 Background and catastrophic tree mortality in tropical moist, wet, and rain forests Lugo, A.E.; Scantena, F.N. Journal Article tropical forests
1996 Biodiversity and biogeochemical cycling
Silver, W. L, S. Brown, and A. E Lugo. 1996. Biodiversity And Biogeochemical Cycling. In Biodiversity and Ecosystem Processes in Tropical Forests, Biodiversity and Ecosystem Processes in Tropical Forests, G. Orians, Dirzo, R., and Cushman, H. Springer-Verlag, Heidleberg, 49-67.
Silver, W.L.; Brown, S.; Lugo, A.E. Book Chapter tropical forest
1996 Birds
Waide, R. B. 1996. Birds. In The food web of a tropical rain forest, The food web of a tropical rain forest, P.D. Reagan and Waide, R. B. Chicago, Illinois: University of Chicago Press, 363-398.
Waide, R.B. Book Chapter tropics
1996 Changes in nutrient cycling during tropical deforestation Garcia-Montiel, D. Thesis biogeochenistry; nutrient cycling; tropical deforestation; tropical forest
1996 The community food web: major properties and patterns of organization
Reagan, P.D., G. Camilo, and R. B Waide. 1996. The Community Food Web: Major Properties And Patterns Of Organization. In The food web of a tropical ra in forest, The food web of a tropical ra in forest, P.D. Reagan and Waide, R. B. Chicago, Illinois: University of Chicago Press, 461-510.
Reagan, P.D.; Camilo, G.; Waide, R.B. Book Chapter tropics
1996 Distribution and abundance of tropical freshwater shrimp along a stream corridor: response to disturbance Covich, A.; Crowl, A.T.; Johnson, A.H.; Pyron, M.

Different intensities and frequencies of disturbances can alter spatial and temporal patterns of abundances for coexisting species. We observed the effects of a high-flow event generated by Hurricane Hugo (19 September 1989) and below-normal stream flow during 1994 on freshwater shrimp populations in a tropical, montane stream. To determine if these different hydrologic regimes altered distributions of populations, we compared shrimp densities during three periods: pre-Hurricane Hugo (20 mo), post-Hurricane Hugo (50 mo), and low-flow (12 mo). There were significant differences in the relationships between locations of stream pools along an elevational gradient (300 to 470 m) and the abundances of two species of shrimp (Atya lanipes and Xiphocaris elongata) during these three periods. Atypa increased in density with increasing elevation in a consistent fashion during all three periods. Densities also increased during the post-Hugo and low-flow periods relative to the pre-Hugo baseline. Xiphocaris increased in density with increasing elevation during the pre- and post-Hugo periods, but density decreased with elevation during the low-flow period. Palaemonid species of predatory shrimp, Macrobrachium carcinus and Macrobrachium crenulatum, consistently decreased in density with elevation during all three periods of observation. Multiple regression analyses demonstrated high predictability of Atya density distributions based on volume, pool depth, and coefficient of variation of pool depth during the pre-Hugo baseline observations. Xiphocaris densities were positively associated with pool width and negatively associated with the coefficient of variation of pool width in the pre-Hugo period. However, physical variables did not predict Atya or Xiphocaris densities during the post-Hugo period. During the dry period, there was a negative association between Atya densities and pool depth and width, and a positive association with the coefficient of variation of pool depth. During the dry period, Xiphocaris densities were best predicted as a function of maximum depth; there was a negative association with the coefficient of variation of pool width. Pre-Hugo Macrobrachium densities were negatively associated with the coefficient of variation of pool width, pool width-to-depth ratio, and elevation; in the post-Hugo and dry periods, Macrobrachium densities were best predicted by elevation. Mechanisms that likely cause these patterns of distribution include avoidance of predators coupled with active preference by prey species for pool habitats with low frequency of washout by storm flows, and with sufficient storage of food resources (microbially conditioned leaf detritus).

Journal Article Xiphocaris
1996 Do seasonality and disturbance influence reproduction in fresh water atyid shrimp in headwater streams, Puerto Rico Johnson, A.H.; Covich, A.; Crowl, A.T.; Estrada, C.; Bithorn, J.; Wurtsbaugh, W. Journal Article xiphocaris enlongata
1996 Earthworm abundance and distribution pattern in two plant communities within a subtropical wet forest of Puerto Rico González, G.

The abundance and distribution patterns of earthworms were studied in two plant communities within a subtropical wet forest in the Luquillo Experimental Forest of Puerto Rico. One plant community is dominated by Dacryodes excelsa, Manilkara bidentata, Guarea guidonea, and Sloanea berteriana and the other by Heliconia caribaea and Prestoea montana. The former is found along ridges and hillslopes and is predominantly associated with Zarzal soil series; the latter is often found in valleys where Coloso soil occurs. A litter manipulation experiment was carried out to examine the relationship between litter input and earthworm abundance in the two plant communities. Three treatments(control, litter removal, and litter addition) were randomly assigned to plots that were established near to and away from Dacryodes trees and Heliconia clones. Litterfall was collected at both locations in each of the communities. Earthworm biomass and density in the Dacryodes community were twice as high as those in the Heliconia community. Earthworm distribution was clumped in both plant communities, but more aggregated in the Heliconia community. Litterfall rate did not differ between Dacryodes and Heliconia communities. Litter Mg and Ca concentrations were lower and C/P ratio was higher in the Dacryodes than in the Heliconia community. Within Dacryodes community, earthworm density or biomass did not differ between areas near to and away from Dacryodes trees. In contrast, abundance of anecic worms was higher in areas away from than to near the Heliconia clones. Dry weight of total earthworms tended to be higher in the litter addition treatment than the control within the Heliconia community. These data indicate that the effects of litter quantity and quality on earthworm abundance vary with plant communities within the subtropical wet forest.

Thesis subtropical wet forest
1996 Earthworm abundance and species composition in abandoned tropical crop lands: comparisons of tree plantations and secondary forests González, G.; Zou, X.M.; Borges, S.

We compared patterns of earthworm abundance and species composition in tree plantations and secondary forests of Puerto Rico. Tree plantations included pine (Pinus caribaea Morelet) and mahogany (Swietenia macrophylla King) established in the 1930s; 1960s; and 1970s; secondary forests were naturally regenerated in areas adjacent to these plantations. We found that (1) earthworm density and fresh weight in the secondary forests were twice as those in neither of the three plantations, and did not differ between plantations, and (2) the exotic earthworm species, Pontoscolex corethrurus Müller, dominated both plantations and the secondary forests, but native worm species, Pontoscilix spiralis Borges & Moreno, Estherella montana Gates and E. gatesi Borges & Moreno, occurred only in he secondary forests. Our results suggest that naturally regenerated secondary forests are preferable to pine and mahogany plantations for maintaining a high level of earthworm density, fresh weight, and native species.

Journal Article Swietenia macrophylla
1996 Ecosystem development and plant succession on landslides in the Caribbean Walker, L.A.; Zarin, D.J.; Fetcher, N.; Myster, R.W.; Johnson, A.H. Journal Article tropics
1996 The effect of perch diameter on escape behavior of Anolis lizards: laboratory predictions and field tests Losos, E.; Irschick, D.J. Journal Article perchs
1996 Effects of changes in biodiversity on ecosystem function in tropical forests Silver, W.L.; Brown, S.; Lugo, A.E. Journal Article tropics
1996 Effects of hurricane disturbance on groundwater chemistry and riparian function in a tropical rain forest McDowell, W.H.; McSwiney, C.P.; Bowden, R.D. Journal Article tropical rain forest
1996 Effects of land use change on northeastern Puerto Rican rivers Clark, D.A. Thesis land use change; limnology; Puerto Rican rivers; Tropical stream
1996 Effects of light, moisture, temperature and litter on the regeneration of five tree species in the tropical montane wet forest of Puerto Rico Everham, E.; Myster, R.W.; Vandegenachte, E.

Field experiments were conducted to investigate the effects of light, moisture, temperature, and litter on the regeneration of two early-, one mid-, and two late-successional tropical tree species High light and litter seem to be universally good cues for regeneration, increasing seed/seedling survival for all species except for Cecropia (an early-successional species) whose small seeds may not be able to penetrate the litter layer. In addition, the high temperature environment in both artificially shaded and nonshaded areas of a natural gap exhibits less seed loss, an increase in the percent and rate of germination, and an increase in seedling survival for Dacryodes (a late-successional species), than the lower temperature environment under an intact canopy Low soil water is also a good cue for Dacryodes germination as it is for Prestoea and Cecropia Finally, the lower temperature environment found under the forest canopy (compared to the natural gap) leads to less seed loss and more germination for Guarea (a mid-successional species) Our results suggest that a good patch for regeneration of many species in this forest, early- as well as late-successional species, would have high light and a litter layer that moderates temperature and moisture extremes. The substantial variation in suitability among regeneration filters and species could: (1) contribute to low establishment success, i e., most dispersed propagules do not become trees, (2) make it difficult to group species into germination strategies, and (3) make it hard to generalize about a net effect of any specific environmental variable on establishment. We suggest that tropical disturbances should be viewed in terms of their impact on a variety of environmental cues, which may signal germination and impact subsequent growth and survival

Journal Article tropical montane wet forest
1996 Endophytic fungi of Manilkara bidentata leaves in Puerto Rico Lodge, D.J.; Fisher, P.J.; Sutton, B.C. Journal Article Xylaria
1996 A fifty-three year record of land-use change in the Guanica forest biosphere reserve and its vicinity
Lugo, A. E, O.M. Ramos, M. Molina, F. N Scantena, and . 1996. A Fifty-Three Year Record Of Land-Use Change In The Guanica Forest Biosphere Reserve And Its Vicinity. Rio Piedras, PR: International Institute of Tropical Forestry, USDA Forest Service.
Lugo, A.E.; Ramos, O.M.; Molina, M.; Scantena, F.N.; , Book macroecology
1996 The first five years in the reorganization of aboveground biomass and nutrient use following Hurricane Hugo in the Bisley Experimental Watersheds, Luquillo Experimental Forest, Puerto Rico Scantena, F.N.; Moya, S.; Estrada, C.; Chinea, J.D. Journal Article recovery
1996 Forest damage and recovery from catastrophic wind Everham, E.; N. V. L. Brokaw

The literature on the effects of catastrophic wind disturbance (windstorms, gales, cyclones, hurricanes, tornadoes) on forest vegetation is reviewed to examine factors controlling the severity of damage and the dynamics of recovery. Wind damage has been quantified in a variety of ways that lead to differing conclusions regarding severity of disturbance. Measuring damage as structural loss (percent stems damaged) and as compositional loss (percent stems dead) is suggested as a standard for quantifying severity. Catastrophic wind produces a range of gaps from the size caused by individual treefalls to much larger areas. The spatial pattern of damage is influenced by both biotic and abiotic factors. Biotic factors that influence severity of damage include stem size, species, stand conditions (canopy structure, density), and the presence of pathogens. Abiotic factors that influence severity of damage include the intensity of the wind, previous disturbance, topography, and soil characteristics. Recovery from catastrophic wind disturbance follows one of four paths: regrowth, recruitment, release, or repression. The path of recovery for a given site is controlled both by the severity of disturbance and by environmental gradients of resources. Recovery is influenced also by frequency of wind disturbance, which varies across geographical regions. To develop robust theories regarding catastrophic wind distu