Simulation of Leaf Area Index and Biomass at Landscape Scale Using Remote Sensing Inputs and Surface Data

摘要

The method for simulating the temporal and spatial distribution patterns of leaf area index (LAI) and biomass at landscape scale using remote sensing images and GIS was discussed in the paper. The procedure was: (1) yearly maximal NDVI of entire landscape was calculated from a TM image; (2) the relationship model between NDVI and LAI was build and yearly maximal LAI of entire landscape was simulated; (3) the relationship models between LAI and biomass were build and yearly branch, stem, root and maximal leaf biomass of entire landscape were simulated; (4) spatial distribution patterns of leaf biomass and LAI in different periods all the year round were obtained. The simulation was based! on spatial analysis module GRID in ArcInfo software. The method is also a kind of upscaling method from patch scale to landscape scale. A case study of Changbai Mountain Natural Preserve was dissertated. Analysis and primary validation were carried out to the simulating results of LAI and biomass for the major vegetation types in Changbai Mountain for 1995. The following results were obtained: (1) seasonal variation of LAI in entire natural preserve was very apparent with single peak pattern; (2) yearly mean LAI of mixed broad-leaved and Korean pine forest was maximal (5.606m~2·m~(-2)), and that of alpine grass was minimal (0.102m~2·m~(-2)) in all the vegetation types; (3) for broad-leaved forest, its branch, stem, root and maximal leaf biomass were maximal; however, those of alpine grass were minimal; (4) in the whole, the simulations agreed with field measurements from some literatures, however, some differences existed among different vegetation types.