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 improvernyield modelling, as they supply up to date informationrnon crop growth, which has been demonstratedrnsuccessfully with the land-surface model PROMET.rnHowever, the availability of optical products forrnbiomass development depends on weather, since cloudrnfree conditions are required. This problem offers anrnopportunity for SAR data, because SAR systems mayrnpenetrate clouds and as active systems can observe evenrnby night.rnIn this study, the possibility of using TerraSAR-X datarnfor mapping crop growth and the accuracy of using TSXrndata for Leaf Area Index retrieval was compared tornoptical approaches. It is evaluated, whether X-band datarncan substitute or complement optical data in the contextrnof data assimilation for improved crop growthrnmodelling and yield prediction. The question ofrnadequate spatial aggregation of the SAR signal forrnagricultural monitoring is addressed and whether thernspatial details observed with TerraSAR-X still allow forrnsite-specific applications.