Combining optical remote sensing data with in-situ measurements in order to estimate vegetation parameters on agricultural fields and corresponding uncertainties

摘要

The estimation and quantification of vegetation parameters on field-scale is necessary to make statements about potential yield and the heterogeneity of its spatial distribution. The ESA satellite mission Sentinel-2 provides optical remote sensing data with a high temporal resolution allowing for an extensive monitoring of agricultural fields. In order to quantify the vegetation parameters as well as to calibrate and validate regression models, additional in-situ measurements are essential. Comprehensive field measurements in two study areas in Germany have been conducted in the growing season 2017 parallel to Sentinel-2 image acquisitions. All ground truth data form a dense time series of the vegetation parameters crop height, crop coverage, chlorophyll content, leaf area index, and wet and dry biomass. First results show a strong linear relation between dry and wet biomass, whereas the slope of the regression line changes with increasing phenological growth stage. Furthermore, there is a clear relationship between in-situ measured wet and dry biomass and NDVI in the early vegetation period, but a saturation occurs in later growth stages. The paper represents a status report of current work in progress, reports first results and gives an outlook of future work.