Drought Risk Assessment Of Rice In East China Based On EPIC Model

Rice is one of the main grain crops in China.Insufficient rice yield will seriously affect national food security.Drought is one of the many natural disasters that threaten the yield of rice.In order to reduce the loss of rice,the drought risk of rice needs to be evaluated.East China is one of the important rice production bases in China.The drought risk assessment of rice in East China is helpful to optimize the field management plan,reduce the drought risk and increase the yield of rice.The drought risk of rice is the result of the interaction among the danger of hazardformative factors,vulnerability of hazard-affected bodies and exposure of hazardformative environments.Rice drought risk assessment is a comprehensive and quantitative assessment of potential drought losses to rice in the future.There are three evaluation methods.The vulnerability curve method can be used to quantitatively evaluate the relationship between disaster and damage in rice drought;The system simulation method can be used to simulate growth of rice under the drought scenario,which can predict and calculate the risk data of rice drought in advance;Based on the theory of regional disaster system,the relationship between the hazard-affected bodies,hazard-formative factors and hazard-formative environments can be comprehensively analyzed.In this paper,three methods were used to quantitatively and systematically evaluate the drought risk of rice.Firstly,the EPIC(Environmental Policy Integrated Climate)model parameters were corrected according to the data of meteorological,soil,rice crop parameters,rice growth period parameters and rice yield per unit area.Secondly,current and future drought risk of rice was assessed in East China.Thirdly,a vulnerability curve was constructed to quantitatively evaluate the drought loss of rice.Finally,Rice drought risk in East China was comprehensively evaluated in three periods: the near-term(2000-2019),the medium-term(2010-2030)and the long-term(2030-2050).The main findings are as follows:(1)Rice drought danger was evaluated in East China.The model parameters were to verified.EPIC model can well simulate the growth and development of rice;Drought danger map of rice was drawn out in different years.Currently,Fujian,Shandong and Jiangxi provinces have high drought danger indeics;Under the situation of RCPs concentration,the rice yield per unit area has an increaseing trend.Before 1950 s,rice per unit area increased rapidly;The drought danger map of rice in different periods was compared.In the future,the drought danger of rice in East China will firstly increase and then decrease.(2)Rice drought Vulnerability was evaluated in East China.Based on drought scenario,the vulnerability curves were drawn.The drought vulnerability curve of rice is roughly S-shaped;At the provincial level,rice drought vulnerability is high in Anhui and Shandong Province.On the geomorphic unit,the drought vulnerability of rice is high in plain and platform;Factors affecting vulnerability include planting area,economic level,exposure and risk,etc;There are three ways to reduce vulnerability: hazard-formative factors,hazard-affected bodies and hazard-formative environments.(3)Rice drought risk was evaluated in East China.Expected risk and the risk in different years was analyzed.The spatial and temporal dynamic distribution of rice drought risk were studied.Currently,Shandong,Jiangxi and Fujian Province are highrisk areas.These places should take active measures to mitigate the risk;In the future,the rice drought risk will firstly increase and then decrease.The risks are rising rapidly in Fujian and Anhui Provinces;Three measures in vulnerability,danger and Exposing can reduce the drought risk of rice.