A Verification Method for Indirect Measurement of Ground Leaf Area Index

Abstract

The invention relates to a verification method for indirect measurement of a ground leaf area index (LAI). The method includes the steps that a virtual plant geometric model base and a virtual vegetation scene base are set up; an observation scheme is designed, simulation implementation is carried out in a virtual vegetation scene according to the principles of all indirect measurement methods of the ground LAI and the observation scheme to form a simulation database; the sum total of the area of xylon parts and the area of triangular patches of leaves in the scene is counted to obtain true values of the LAI, the WAI, the PAI, the parameter of the xylon total area ratio, base components of canopies and the xylon component aggregation index; simulation results of all the measurement methods of the LAT are calculated, the true values of the scene are taken as the simulation calculation results to verify reference values, and the existing indirect measurement methods of the ground LAI are improved, realized in the virtual vegetation scene base and repeatedly circulated to obtain the final existing indirect measurement method of the ground LAI. The verification method does not need to destructively sample vegetation, manpower and material resource investments are small, and verification efficiency, precision and expandability are improved substantially.

Description

technical field

[0001] The invention relates to an indirect measurement verification method of ground leaf area index. Background technique

[0002] Leaf area index (LAI) is dimensionless, it controls a variety of biophysical and physiological processes of vegetation canopy, such as photosynthesis, respiration, transpiration, carbon cycle, precipitation interception and energy exchange, so LAI is widely used There are a large number of application requirements in the fields of vegetation growth and productivity models, crop growth models, net primary productivity models, atmospheric models, hydrological models, forestry, botany, ecology, agronomy and other fields, and in actual production and scientific research activities. In view of the traditional optical LAI measurement method, the measured canopy radiation interception includes the contribution of canopy wood components, so the measurement result is PAI (plant area index, total area index). The difference between PAI a...

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