New poster on crop growth and water availability

During the recent EGU 2023, Sneha Chevuru from Utrecht University shared a poster entitled “Feedback between water availability and crop growth using a couple hydrological-crop production model“. To understand her poster best, read more below about the research activities conducted in the framework of GoNexus and their outputs.

Climate change and increases in extremes, such as heatwaves and droughts, threaten crop production and food security in various regions worldwide. Irrigation is increasingly used to secure stable yields, increasing the competition for available water resources with other sectors.

To assess the vulnerability of crop production under present and future drought and heatwave events, the two-sided interactions between crop growth and hydrology should be represented by a coupled model system, combining the strength of both a crop model and a global water resource model.

The main objective of Sneha’s team, therefore, is to quantify the mutual feedback between crop production and hydrology under climate extremes (i.e., droughts and heatwaves) in various regions globally. To this end, we have developed a coupled hydrological-crop model framework, coupling the PCR-GLOBWB2 water resources model to the WOFOST crop model.

The coupled model framework operates on high spatiotemporal resolution (daily time step up to 30 arc minutes) to assess the two-way interaction between hydrology and crop production (maize, wheat, rice, and soybean) for irrigated and rainfed agriculture.

Sneha and her colleagues first established a one-way coupling to evaluate the effect of the simulated water availability in terms of soil moisture of PCR-GLOBWB2 on crop production in WOFOST. Next, they established a two-way coupling in which the vegetation dynamics of WOFOST determine the evapotranspiration, which is fed back into PCR-GLOBWB2 and affects the soil moisture status. The individual WOFOST and the coupled one-way runs were compared in terms of crop production.

Results show that soil moisture is over or underestimated in the western part of the CONUS. Vegetative dynamics provides a better understanding of the impacts and therefore, a two-way interaction is needed to further investigation.