Comparison of direct and indirect methods for assessing leaf area index across a tropical rain forest landscape

Paulo C. Olivas; Steven F. Oberbauer; David B. Clark; Deborah A. Clark; Michael G. Ryan; Joseph J. O'Brien; Harlyn Ordonez

Treesearch

Comparison of direct and indirect methods for assessing leaf area index across a tropical rain forest landscape

Formally Refereed

Authors:

Paulo C. Olivas, Steven F. Oberbauer, David B. Clark, Deborah A. Clark, Michael G. Ryan, Joseph J. O'Brien, Harlyn Ordonez

Year:

2013

Type:

Scientific Journal

Station:

Rocky Mountain Research Station

Source:

Agricultural and Forest Meteorology. 177: 110-116.

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Abstract

Many functional properties of forests depend on the leaf area; however, measuring leaf area is not trivial in tall evergreen vegetation. As a result, leaf area is generally estimated indirectly by light absorption methods. These indirect methods are widely used, but have never been calibrated against direct measurements in tropical rain forests, either at point or landscape scales. Here, we compare direct harvest leaf area index (LAI) measurements taken across an old-growth tropical rain forest landscape with data from two indirect methods, digital hemispherical photography and the LI-COR LAI-2000 Plant Canopy Analyzer. Direct measurements of leaf area were done by collecting all leaf material within an area of 4.6 m2, extending from the forest floor to the top of the canopy using a portable aluminum scaffolding tower. The tower was erected at 45 locations following a stratified random design.

Keywords

La Selva Biological Station, hemispherical photography, LAI-2000, leaf area index, plant area index, wood area index

Citation

Olivas, Paulo C.; Oberbauer, Steven F.; Clark, David B.; Clark, Deborah A.; Ryan, Michael G.; O'Brien, Joseph J.; Ordonez, Harlyn. 2013. Comparison of direct and indirect methods for assessing leaf area index across a tropical rain forest landscape. Agricultural and Forest Meteorology. 177: 110-116.