LUQ LTER DATA SETS DOCUMENTATION FORM

ON-LINE VERSION

A DATA SET is a series of observations collected by the same methodology. Each data set should have documentation sufficient for someone unfamiliar with the research to replicate the study. Data sets may be broken into subsets (data files) that are discrete in space and time, in that order. The documentation for a data set should include all spatial and temporal subdivisions of the data.

NOTES:

• Add rows to tables or lines to paragraphs as you need them for entering your data.
• Contact emelendez@lternet.edu if you have any question.
• See online Guidelines (http://luq.lternet.edu/datamng/imdocs/division.html) to help you fill this form
• Get the description online of any of the highlighted item by locating your cursor on top of the item, holding the [Ctrl] key while left-clicking your mouse.

DATA SET IDENTIFIER: Canopy Trimming Experiment (CTE) Snail data

PROJECT TITLE: CTE

PROJECT DESCRIPTION: This long-term experiment will increase the frequency of simulated hurricane effects above background levels to once every six years. The experiment will determine effects of repeated disturbance of the forest canopy and increased detrital inputs to the forest floor on germination, growth, survival, nutrient cycling, soil conditions, and trophic structure. Climate change models predict increased frequency and intensity of Caribbean hurricanes (Emmanuel 1987, Goldenberg et al. 2001), and our goal is to evaluate predictions regarding the effects of an increased rate of hurricane disturbance on tabonuco forest (Sanford et al. 1991). The experiment also is designed to decouple the effects of canopy disturbance (e.g. , light levels, temperature, moisture, etc. ) from those of increased detrital inputs on rates of detrital processing and resultant community and ecosystem processes. Manipulations and measurements of detrital processing, SOM, and soil properties associated with SOM will continue for at least three more funding periods (until 2024). In the short-term, we will use faunal manipulations nested within the canopy trimming experiment to measure the strength of interactions between autotrophic and detrital food webs in the context of hurricane-like disturbance. These results will be directed specifically at parameterizing the Trophic Interaction Model. This experiment also will provide a physical and intellectual focal point for the project participants. The Canopy Trimming Experiment has two parts: 1) a forest canopy manipulation with measurements of coupled changes in microclimate, structure, and biota and their associated impacts on ecosystem processes, and 2) specific manipulations of the biota that assess the importance of components of the food web.

The objective of the CTE snail data is to determine how green litter deposition and canopy opening associated with a hurricane independently and jointly affect population dynamics and community composition of terrestrial gastropods. Because canopy openness can be expected to increase abiotic stress on gastropods, whereas litter deposition should provide increased resources and refugia, tradeoffs can be expected.

LTER CORE AREAS: (Annotate all that apply) (See online list)

Population Dynamics

Disturbance Patterns

LEF LTER 1 RESEARCH TOPIC: Annotate all that apply (See online list)

Recovery After Disturbance

Spatial and Temporal Distribution of Populations

We define a data file as a component of a data set. A data set can have only one data file or more. Basically, different data files have different data structures or format.

DATA SET FILES (SUBSETS):

Data File No.	Data File Identifier	On-Line Filename	Starting Date	Periodicity of sample	End Period
1	CTE Snail Abundances	CTESnailsCaptures2003-7.txt	July 1, 2003	Semi-Annual	Ongoing

RESEARCH LOCATION: Block A: 30+ m West of western edge of Big Grid, on North and South side of Prieta stream, near Vogt old plots. Block B: 30+ m South of Big Grid, all plots along Oxcart Trail. Block C: 30+ m West of SE corner of Big Grid.

SOURCE OF FUNDING (SPONSOR): LTER funding to make the CTE plots, materials & supplies, tech time. USDA Forest Service (FPL, IITF) for scientist's time.

DATA SET METHODS: Plots were sampled during two time periods each year:  March (“Dry” season) and July or August (“Wet” season).  During each sampling period, there were 3-4 nocturnal surveys of each CTE plot.  Researchers were randomly assigned to subplots within each plot.  Each time a subplot was sampled, the surveyor spent 15 minutes searching all exposed surfaces (e.g., vegetation, rocks, leaf litter, soil surface) within the boundary of the subplot for snails and slugs.  All surveyors were instructed to minimize trampling damage to the plots by using walkways whenever possible, to avoid at all costs stepping in the seedling plots, and to avoid disturbing the plots by sifting through leaf litter, turning over rocks or dead wood, etc.  Snails and slugs were identified to species but, whenever possible, not removed from their substrate.  Block A was not sampled in March of 2005 because the experimental treatments were underway.

REFERENCES:

CROSS-REFERENCES (other data sets related to this one):

SAMPLE LOCATION:
All CTE plots (Example of the Litter decomposition and Connectivity basket data):

STORAGE SITES(of data files): Sabana Field Research Station, Mycology, Module, Institute for Tropical Ecosystem Studies (ITES) of the University of Puerto Rico, Río Piedras

INVESTIGATOR'S ASSIGNED KEYWORDS:

LEF LTER OFFICIAL KEYWORDS (See table): EL VERDE, CTE blocks, TABONUCO, DISTURBANCE, GASTROPODS

PUBLICATIONS:

Bloch CP, Zimmermann CR, Brokaw NVL, Thompson J, Willig MR. 2006. “Heterogeneity, scale, and biotic responses to disturbance in the Luquillo Experimental Forest: case studies from the Luquillo Forest Dynamics Plot.” Long-Term Ecological Research Network, All Scientists Meeting, 19-23 Sept. 2006, Estes Park, CO. (poster presentation)

Zimmerman J, Shiels A, Bloch C, Cantrell S. Crowl T, Cruz C, Garcia L, González G, Klawinski P, Lebrón L, Lodge DJ, McDowell W, Melendez-Colom E, Prather C, Ramirez A, Reese E, Richardson B, Richardson M, Rivera F, Schowalter T, Sharpe J, Silver W, Brokaw N. 2006. “The Canopy Trimming Experiment at LUQ.” Long-Term Ecological Research Network, All Scientists Meeting, 19-23 Sept. 2006, Estes Park, CO. (poster presentation)

REASONS TO RESTRICT DATA IN THIS DATA SET BEYOND ITS TWO YEAR POLICY PERIOD*:

*WILL HAVE TO BE APPROVED BY AT LEAST ONE LUQ LTER PRINCIPAL INVESTIGATORS: N. Brokaw, J. ZIMMERMAN, A. LUGO

SITES DESCRIPTIONS: Block A: Elevation (340-360); aspect SW-facing; Location 30+ m West of western edge of Big Grid, on North and South side of Prieta stream, near Vogt old plots. Block B: Elevation (450-485); aspect W-SW facing; Location 30+ m South of Big Grid, all plots along Oxcart Trail. Block C: Elevation (435-480 m); aspect West-facing; Location 30+ m West of SE corner of Big Grid.

Geographical positional system (GPS) Coordinates for each location:

location	latitude	longitude

The following table displays the x and y coordinates in Puerto Rico Planar Coordinates:

BlockPlot	X	Y
A1	217379	54625
A2	217437	54631
A3	217423	54720
A4	217460	54684
B1	217824	54356
B2	217875	54344
B3	217913	54278
B4	217970	54217
C1	217878	54476
C2	217933	54476
C3	217998	54480
C4	218094	54544

VARIABLES (ATTRIBUTES):

File Name or # above (all in which the variable appears)	1	1	1	1	1
AbbreviationAbbreviation(as it appears on the data file)	BLOCK	PLOT	SUBPLOT	RUN	DATE
NAME OF VARIABLE	Block identifier	Plot Identifier	Subplot Identifier	Sampling Run	Date of sample
DEFINITION OF VARIABLE	Name given to a grouping of 4-like plots in one of three locations. No data is missing in this field.	Name given to a 20m X 20m plot of a Block. No data is missing in this field.	Name given to a 4.7m X 4.7m of a plot within a block. No data is missing in this field.	Each subplot is sampled 4 times. The sampling run indicates which of those times each data point represents.	The date in which the subplot was sampled
UNIT
PRECISION
RANGE OR LIST OF VALUES	A = West of western edge of Big Grid plot B = South of Big Grid C =  West of SE	1,. . . , 4	1,. . . , 16	0,..., 4
DATA TYPE	alphabetic	integer	integer	integer	datetime
MISSING DATA CODES

VARIABLES (ATTRIBUTES):

VARIABLES (ATTRIBUTES):

VARIABLES (ATTRIBUTES):

VARIABLES (ATTRIBUTES):

VARIABLES (ATTRIBUTES):

COMPUTATIONAL METHODS:

Variable Name	Formula

FOR DATA MANAGER USE ONLY

DATE OF LAST REVIEW: May 19, 2009
DATE OF LAST ENTRY:2005
STAGE OF DATA SET MANAGEMENT (dates):
RECEIVED: January 11, 2006
ENTERED: January 11, 2006
FILED ON-LINE:
REVIEWED BY RESEARCHER:

Rev. date of this form: 28 July 200/ 15 July  2001/June 9, 2003/March 16, 2004/12 April 2005/ 8 November 2005/ 16 January 2006