Study On The Structure Optimization Of Planting Industry In Irrigation District Under The Restriction Of Water Resources

At present,how to realize the sustainable development of agriculture is the primary problem to realize regional sustainable development.Among them,optimizing cropping structure according to local conditions is one of the methods to realize the sustainable development of agriculture.The Heihe irrigation area in the arid region of northwest China and the Fenhe irrigation area in the semi-arid region,the amount of water resources is the lifeblood that restricts the development of the two regions.How to realize the sustainable development of agriculture under the premise of water resources constraint is the main problem to be solved in this paper.In addition,through the horizontal comparative analysis of the present situation of the two major irrigation areas,the similarities and differences between regions are further clarified,in order to achieve a clear direction for regional sustainable development.Zhangye is a grain base in the arid region of northwest China.Agricultural water consumption accounted for the heaviest,up to 89.57%.With the development of economy,agricultural water has seriously squeezed the water used in life and industry,and the contradiction between water use structure is becoming more and more serious.At the same time the agricultural development in Zhangye City is mainly planting industry,with a single structure,extensive production mode and high input cost.In order to promote agricultural development,the phenomenon of super tillage is serious in recent years,and the extensive chemical use of fertilizers,pesticides and so on has brought a series of new problems such as water pollution.Similar to Zhangye,Taiyuan City is located in the semi-arid area,where living and industrial water use is seriously occupied agricultural water.With the impact of climate change,the shortage of agricultural water resources is even more serious problems.Agriculture is mainly planted with high water consumption,low utilization rate of water resources and high production cost,which makes agricultural economic benefits not outstanding.Based on the analysis of the present situation of the development of the two regions,a linear programming model for optimizing the structure of cropping industry under the constraint of water resources was established according to local conditions.Through the adjustment,it was found that under the condition of promoting social and economic development,saving water resources,cultivated land resources and reducing ecological pressure,the planting industry in both regions has achieved certain development.With 26.3% water saving in agriculture in Zhangye City,the economic benefits of planting increased 4.41×108 yuan.Agricultural water consumption in Taiyuan City saved 0.19×104m3,planting output value increased 0.68×108 yuanBased on the natural conditions,economic development and adjustment results on the horizontal comparative analysis of the two regions,the natural conditions in Taiyuan City are superior to Zhangye,but the agricultural development of the two regions is mainly planting industry,with a single planting structure and a dual grain-economy structure as a whole.The adjustment direction of the two major regions is focused on increasing the area of crops with low water demand and high economic value,and reducing the area of crop cultivation with high water consumption and low economic value.Judging from the overall adjustment amplitude,the structure adjustment of Zhangye is higher than that of Taiyuan City,and the structure adjustment space is larger,while the structure adjustment of Taiyuan City has become reasonable,but there is still room for optimization in the interior.From the internal point of view of structural adjustment,the focus of Zhangye adjustment is mainly on vegetables,fruits and maize crops,and can not be blindly followed in the actual adjustment,It also needs to take into account the advantages of resources,the situation on the spot and the development situation,and further consider the extent of area increase and decrease.Compared with Zhangye,the structural adjustment of Taiyuan City has a wide range,with small changes in grain,economy and other crops.Among them,economic and other crops increased significantly,while food crops decreased appropriately.After adjustment,the development of planting industry in Taiyuan City is not only compatible with the development of social economy,but also further promotes the diversified development of agriculture.