LUQ DATA SET METADATA

Completed

Data Files and Variables

Data File Identifier Data File Collected
Canopy gap survey at El Verde
text/plain iconGapsurve.txt
 11/01/1988 - 11/07/1988

Measurements:

Gap identification code
length
width
8
Canopy gap survey at El Verde

Research Sites:

El Verde Research Area Cecropia saplings gaps (1-76)

Methods:

Within this area, the canopy gap area of all recent gaps (sept. 1989) are marked with yellow flagging and have been roughly measured. Each gap has a unique identifying number. Canopy gap area is determined by measuring with a rangefinder, or estimating, the lenght of the long and short axes of the hole in the canopy and using these figures to calculate the area of an ellipse as an approximation of the gap area.

Abstract

The survey of gaps at El Verde covers about 35 ha, including the 9 ha grid. We defined a treefall gap at El Verde as a hole in the forest canopy extending down to an average height of about 3 m or less above ground. The edge of a gap was delineated by the vertical projection of the edge of the canopy foliage. We measured the dimensions of all gaps present in the 35-ha study site in August 1989, one month before Hurricane Hugo. For each gap we measured L, the longest axis of the gap (distance between edges), and W, the longest axis perpendicular to L, and then approximated gap area as that of an ellipse: Area = p LW/4 (Runkle 1992). Only openings ³ 20 m2; were counted as gaps.

List of Publications:

Disturbance and canopy structure in two tropical forests

Related Project:

Owner:

Nicholas Brokaw

Contact(s):

Nicholas Brokaw

Researcher's Keywords:

canopy
tabonuco forest
treefall gap
Puerto Rico
LUQ
Luquillo

LTER Core Area(s):

disturbance
primary production

Complete Metadata:

  • Canopy gap survey at El Verde

    The basic information about a dataset

    Basic Information

    Program: 
    Luquillo LTER
    Luquillo Investigator Research
    Numeric Dataset ID: 
    8
    Data Set Identifier: 
    Canopy gap survey at El Verde
    Duration: 
    Completed
    Abstract: 

    The survey of gaps at El Verde covers about 35 ha, including the 9 ha grid. We defined a treefall gap at El Verde as a hole in the forest canopy extending down to an average height of about 3 m or less above ground. The edge of a gap was delineated by the vertical projection of the edge of the canopy foliage. We measured the dimensions of all gaps present in the 35-ha study site in August 1989, one month before Hurricane Hugo. For each gap we measured L, the longest axis of the gap (distance between edges), and W, the longest axis perpendicular to L, and then approximated gap area as that of an ellipse: Area = p LW/4 (Runkle 1992). Only openings ³ 20 m2; were counted as gaps.

    Short name: 
    LUQMetadata8
    Project Title: 
    Core Area: 
    disturbance
    primary production
    Researchers´ Keywords: 
    canopy
    tabonuco forest
    treefall gap
    Puerto Rico
    LUQ
    Luquillo
    2006 Proposal Classification: 
    Habitat
    Table 4 Long-Term Classification: 
    treefall gaps
    disturbance
    Data File Structure Reference: 
    Canopy gap survey at El Verde
    Station Acronym: 
    LUQ
    Data File Structure Referrer: 
    Bibliography: 
    Disturbance and canopy structure in two tropical forests

    Personnel

    Owner: 
    Nicholas Brokaw
    Contact: 
    Nicholas Brokaw
    Data Manager: 
    Eda Melendez-Colom

    Georefs, Dates

    Publication Date: 
    04/11/2011
    Site: 
    El Verde Research Area Cecropia saplings gaps (1-76)
    Collected: 
    11/01/1988 - 11/30/1988

    Methods

    Methods: 

    Within this area, the canopy gap area of all recent gaps (sept. 1989) are marked with yellow flagging and have been roughly measured. Each gap has a unique identifying number. Canopy gap area is determined by measuring with a rangefinder, or estimating, the lenght of the long and short axes of the hole in the canopy and using these figures to calculate the area of an ellipse as an approximation of the gap area.

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