Use of MODIS products to assess the impacts of the 2012 drought on ET and GPP in a perennial agriculture system in Kansas

摘要

The objective of this study is to evaluate the impacts of the severe drought in the central US in 2012 on ET and GPP in a perennial wheatgrass crop in Kansas utilizing Moderate Resolution Imaging Spectroradiometer (MODIS) products. The study period comprises three years (2012, 2013 and 2014). In the drought year (2012), the annual ET and GPP were ~24% and ~12% lower than the average for the wet years (2013 and 2014). The 2012 drought caused a higher impact on ET in comparison with GPP. Overall, the reductions on ET and GPP occurred as expected and are related to the fact that long periods with low precipitation can deplete soil moisture, inducing stomatal closure and leading to a decline in the photosynthesis rate.