Sensitivity of corn and soybean yields to climatic variables and fertilizer application rates across US: A non-parametric elasticity analysis
Abstract
Climate variability and crop management practices control the crop yield which impacts the local to regional food security. While the sensitivity of crop yield to climatic variables including precipitation and temperature is extensively studied using linear regression models, application of non-parametric elasticity concept is still unexplored in the agricultural sector. Moreover, the sensitivity of crop yields to fertilizer application rate remains uninvestigated across different spatial scales. Therefore, in this study, a non-parametric elastic indicator is used to evaluate the response of de-trended corn and soybean yields to county scale mean areal precipitation, average temperature, average reference evapotranspiration, and average fertilizer application rates across the United States. The results indicate that the de-trended corn yield is negatively (positively) sensitive to precipitation (yield reduces with each % increase in precipitation) in the northern and middle (southern) latitude counties (ranging from -4.4 to -0.1% in northern/middle counties, and 1.0 to 2.3% in southern counties). Similarly, the corn yield is negatively sensitive to average temperature and reference evapotranspiration in the southern (sensitivity ranging from -7.9 to -3.5%) and middle latitude counties, and positive in northern latitude counties. The de-trended soybean yield is found to be positively sensitive to precipitation in the southern and middle latitudes, and negatively sensitive in the northern latitudes. Identical to the corn yield, soybean yield is also noted to be negatively sensitive to average temperature and reference evapotranspiration in the southern and middle latitudes, and positively sensitive in northern latitudes. Both crop yields are noticed to be positively sensitive to fertilizer application with higher sensitivity observed for corn (ranging from 4 to 8%) in the northern latitudes. These findings indicate that proper cropping management is crucial especially in the counties of southern and middle latitudes to avoid crop yield loss. Moreover, applying more fertilizers does not necessarily guarantee a higher yield, this is especially true for soybean in the southern counties. The outputs of this study are highly useful in creating robust agricultural planning.
- Publication:
-
AGU Fall Meeting Abstracts
- Pub Date:
- December 2021
- Bibcode:
- 2021AGUFMGC45H0912D