Study On The Allocation Of Agricultural Water Resources Oriented The Minimization Of Crop Yield Loss Caused By Drought

Drought is one of the most important natural disasters leading to crop yield reduction in China.In order to ensure food security in China,it is very necessary and urgent to study the measures on agriculture drought.With the decline of the proportion of agricultural water resources,how to make the limited agricultural water resources to play its maximum production efficiency is particularly important.This paper takes the Northern Huaihe Plain in Anhui Provinence as the research target,and black soil-summer maizewinter wheat system was taken as research object,we carry out study of the allocation of agricultural water resources oriented the minimization of crop yield loss caused by drought.Based on the ease of soil water utilization,we built agricultural drought evaluation index system according to the level of difficulty to use soil water for summer maize,which improved the accuracy of the agricultural drought evaluation and scientific.An effects evaluation platform of drought on crop yield was developed through prototype observation experiments and crop model simulation,which improved the yield impact assessment of agricultural drought for convenience and accuracy.We obtain subsection water production function under different drought situations.We disscussed the superiority analysis of subsection water production function based on the model of optimizing conjunctive operation of surface water-groundwater.We developed the optimizing conjunctive operation scheme of surface water-groundwater of different growth period in the Northern Huaihe Plain in Anhui Provinence,and evaluated the quantitative ability to cope with agriculture drought.Based on study the main achievments are as following:(1)The crop yield loss caused by drought evaluation methods and historical crop yield loss caused by drought evaluation,The crop yield loss caused by drought evaluation methods through prototype observation experiments and crop model simulation which has good applicability in Anhui Huaibei plain could better simulate yield loss caused by drought,which has good applicability in Anhui Huaibei plain.1961-2015,the total summer maize losses due to drought was 500-1,750 kg/ha,and the total winter wheat losses due to drought was 1,300-1,950 kg/ha.(2)The advantage of the subsection water production function under different drought situations applied to agricultural water resources allocation.We derived winter wheat and summer maize under different drought situations with setting 15 drought situations.Compare to Jensen model,the subsection water production function has better convergence characteristic,computing speed and precision of simulation performance.(3)the optimizing conjunctive operation scheme of surface water-groundwater of different growth period and cope with agricultural drought evaluation effect.We developed the summar maize and winter wheat optimizing conjunctive operation scheme of surface water-groundwater of different growth period based on subsection water production function.After optimal allocation of agriculture water resource,average annual summar maize yield loss percentage would be decreased by 766,000 tons and the loss percengage would be reduced by 15%.Average annual winter wheat yield loss percentage would be decreased by 1,034,000 tons and the loss percengage would be reduced by 10.1%.