Risk assessment of maize drought disaster in southwest China using the Environmental Policy Integrated Climate model

The East Asian monsoon has a tremendous impact on agricultural production in China. An assessment of the risk of drought disaster in maize-producing regions is therefore important in ensuring a reduction in such disasters and an increase in food security. A risk assessment model, EPIC（Environmental Policy Integrated Climate） model, for maize drought disasters based on the Erosion Productivity Impact Calculator crop model is proposed for areas with the topographic characteristics of the mountainous karst region in southwest China. This region has one of the highest levels of environmental degradation in China. The results showed that the hazard risk level for the maize zone of southwest China is generally high. Most hazard index values were between 0.4 and 0.5,accounting for 47.32% of total study area. However,the risk level for drought loss was low. Most of the loss rate was ＆lt;0.1, accounting for 96.24% of the total study area. The three high-risk areas were mainlydistributed in the parallel ridge–valley areas in the east of Sichuan Province, the West Mountain area of Guizhou Province, and the south of Yunnan Province.These results provide a scientific basis and support for the reduction of agricultural drought disasters and an increase in food security in the southwest China maize zone.

Mapping the Global-Scale Maize Drought Risk Under Climate Change Based on the GEPIC-Vulnerability-Risk Model

Drought is projected to become more frequent and increasingly severe under climate change in many agriculturally important areas.However,few studies have assessed and mapped the future global crop drought risk—defined as the occurrence probability and likelihood of yield losses from drought—at high resolution.With support of the GEPIC-Vulnerability-Risk model,we propose an analytical framework to quantify and map the future global-scale maize drought risk at a 0.5°resolution.In this framework,the model can be calibrated and validated using datasets from in situ observations(for example,yield statistics,losses caused by drought)and the literature.Water stress and drought risk under climate change can then be simulated.To evaluate the applicability of the framework,a global-scale assessment of maize drought risk under 1.5℃warming was conducted.At 1.5℃warming,the maize drought risk is projected to be regionally variable(high in the midlatitudes and low in the tropics and subtropics),with only a minor negative(-0.93%)impact on global maize yield.The results are consistent with previous studies of drought impacts on maize yield of major agricultural countries around the world.Therefore,the framework can act as a practical tool for global-scale,future-oriented crop drought risk assessment,and the results provide theoretical support for adaptive planning strategies for drought.

Root architecture

Numerous research publications over the past 20 years have made it quite clear that a better understanding of the molecular and genetic basis for variation in root system architecture（RSA）will greatly aid the development of crop varieties with improved and more ef ficient nutrient and water acquisition under limiting conditions.