LEAF AREA INDEX RETRIEVAL AND YIELD MODELLING FOR WINTER WHEAT WITH TERRASARX DATA COMPARED TO USING OPTICAL DATA

摘要

Plant parameters from remote sensing data improve yield modelling, as they supply up to date information on crop growth, which has been demonstrated successfully with the land-surface model PROMET. However, the availability of optical products for biomass development depends on weather, since cloud free conditions are required. This problem offers an opportunity for SAR data, because SAR systems may penetrate clouds and as active systems can observe even by night. In this study, the possibility of using TerraSAR-X data for mapping crop growth and the accuracy of using TSX data for Leaf Area Index retrieval was compared to optical approaches. It is evaluated, whether X-band data can substitute or complement optical data in the context of data assimilation for improved crop growth modelling and yield prediction. The question of adequate spatial aggregation of the SAR signal for agricultural monitoring is addressed and whether the spatial details observed with TerraSAR-X still allow for site-specific applications.