Simulation modeling of cotton yield responses to management strategies under climate change: insights from DSSAT

Forecasting cotton response to management strategies under climate change is considered an advanced tool for future planning to ensure global fiber security. An existing data set from a long-term cotton field experiment (39 years) at The University of Tennessee Institute of Agriculture Research and Education Center in Jackson was used for this project. This experiment consists of the complete combinations of two tillage systems (no-tillage and conventional tillage), and four nitrogen (N) application rates of 0, 30, 60, and 90 lb acre-1. In this study, climate change impacts on cotton yield responses to management strategies were assessed using the DSSAT model for three projected periods (2030, 2040, and 2050) under the Representative Concentration Pathway 8.5 (RCP8.5). Results were compared with the baseline scenario of 1986-2018. As temperatures rise and rainfall decreases continuously from 2030 to 2050, the trend of cotton yield decreases becomes more pronounced in 2050 compared to 2040 and 2030. Under future climate change, lint yield will suffer severe damage from no or low N application, and intensive conventional tillage. There will be under greater need that apply a high N rate to cotton under no-till production than conventional tillage. Overall, a combination of 60 to 90 lb acre-1 and no-tillage will be warranted to mitigate the negative effects of changing climate on lint yield. In conclusion, results from the DSSAT model provide management strategies on cotton for the future under changing climates. The best management system for future cotton production will be 90 lb acre-1 under no-tillage.