The Construction of the Remote Sensing Estimation Models for Reed Biomass in the Lower Reaches of the Tarim River

Abstract

The remote sensing estimation models for reed biomass were established by using TM data and the field investigation of reed biomass around the Daxihaizi reservoir in the lower reaches of Tarim river.The results show that the gray values of TM1~5 and TM7,the perpendicular vegetation index(PVI),the brightness vegetation index(BVI) and the normalized difference vegetation index(NDVI)are significantly related to the measured values of Phragmites australis biomass,the fitting precision of the nonlinear regression model is higher than that of the linear regression model,and NDVI has the highest precision in the regression models but TM4 has the lowest precision.The multiple stepwise regression has a higher fitting precision than ordinary regressions.The ordinary linear regressions based on PVI and NDVI and the ordinary nonlinear regression based on TM1 are the best options due to the characteristics of simplicity,reliability and convenience.