Impacts of Soil Moisture on Crop Health: A Remote Sensing Perspective

Monitoring the effects of soil moisture on crop health is important for applications such as irrigation decision support, food security, precision agriculture as well as for more broadly understanding relationships between water and carbon cycles. In this study, we examine the relationships between soil moisture and crop health indicators, how they respond to each other on timescales from days to weeks. The satellite-derived indicators considered are the normalized difference vegetation index (NDVI) derived from reflectance obtained with moderately wide (20-40 nm) spectral bands in the visible and near-infrared (NIR) and soil moisture products that extends to about 1 m depth from Soil Moisture Active Passive (SMAP) mission. We find that NDVI have significant correlations with soil moisture in crop fields of Nebraska. Crop types and soil types also greatly influence the correlation between crop health and soil moisture changes at various rates and strength.