Research On Influence Of Water Resources' Non-agriculturization On Grain Production And Countermeasures

As an increasingly scarce natural resource,water resources have a significant impact on food security and agricultural economic development.Although the total amount of water resources in China ranks the top in the world,the per capita share is only 28%of the world average level.In 2018,the per capita water resources is only 1971.8m~3(according to the internationally recognized standard of per capita water resources,less than 2000m~3 is considered as moderate water shortage).China is one of the 13 poor water countries in the world.Of the 31 provinces in China,only 10 provinces such as Heilongjiang,Jiangxi,Tibet and Xinjiang have per capita water resources of more than 2000 m~3.The average water resources per capita in 13 main grain producing areas are only 1458.2 m~3,which is close to severe water shortage(the water resources per capita is less than 1000 m~3).Among them,the water resources per capita in four main winter wheat producing areas,such as Shandong,Hebei,Henan and Jiangsu,are less than 500 m~3,which belong to the area of extreme water shortage.With the acceleration of industrialization and urbanization,China's demand for industrial water and urban water is increasing,the trend of non-agricultural water occupying agricultural water is becoming increasingly significant,the agricultural water supply is declining,it is bound to increase the risk of water for grain production and affect the stability of grain production.How to solve the increasing hard constraints of water shortage on grain production and realize the balanced development of industrialization,urbanization,ecological environment and grain production is a major practical problem in China.Based on this situation,this study has important theoretical and practical significance.Based on the theories of resource allocation,farmers'behavior theory,theory of technology innovation induced by scarcity of factors,this study firstly analyzed the influence mechanism of non-agriculturization of water resources on grain production,and then sorted out the current situation of grain production and water resources in China by using statistical data.By calculating the matching degree between water resources and grain production in different regions,characteristics of regional differences were clarified.Statistical data were used to describe the evolution trend of China's water resources'non-agriculturization,and the Theil index,?convergence,?convergence methods and spatial econometric analysis model were applied to measure the regional differences,convergence trend,spatial correlation characteristics and spatial spillover effect of China's water resources'non-agriculturization;then through the cases and questionnaire the impact of water resources'non-agriculturization on food production were studied from the empirical aspect.Finally,the paper put forward countermeasures from two aspects,efficiency improvement and spatial layout optimization:Global Super Efficiency DEA model and Geographical Weighted Regression(GWR)model were used to measure the water efficiency of grain production and water-saving potential of each province,identify the influence degree of different factors on grain production in different regions,then GIS software was applied to describe the evolution track of centers for water resources'non-agriculturization and grain production,and lastly the study put forward corresponding policy suggestions for realizing the coordinated development of water resources'non-agriculturization and grain security.The main conclusions are as follows:Firstly,the impact mechanism of water resources'non-agriculturization on grain production is relatively complex.Theoretically,resources'non-agriculturization conforms to the goal of water resources optimal allocation with efficiency as the primary goal,and has dual effects on grain production:on the one hand,water resources'non-agriculturization has both the effect of water-saving technology substitution and agricultural labor productivity improvement on grain production.The huge gap between income of agricultural water resources utilization and income of non-agricultural water use can induce local governments to put scarce water resources into industries with higher marginal benefit,realize the maximization of local income,improve the government's public investment and service level in agriculture,strengthen the construction of agricultural production infrastructure,promote the use of water-saving facilities,save agricultural water resources,and ensure food production;labor forces'non-agriculturization can promote the substitution of input factors in grain production,at the same time,it is conducive to the formation of large-scale operation of land circulation,promote the use of water-saving technology,and improve grain production capacity.On the other hand,non-agriculturization of water resources poses a potential risk to food production:through the reduction of water consumption for food production,it causes the shortage of water for food production,and induces the adjustment of farmers'planting structure.Driven by the goal of maximizing the interests,the grain yield and planting area are affected by farmers'reducing irrigation times and adjusting planting structure,thus threatening food security.Through case analysis and questionnaire survey,this paper confirms the negative impact of water resources non-agriculturization on grain production from the micro level,and the comprehensive factors such as individual characteristics and family characteristics affect the adoption of water-saving technology of farmers.At the macro level,according to the panel data of 13 major grain producing areas,the impact of water resources'non-agriculturization on grain production is calculated,and the regional differences are obvious.Secondly,there are significant regional differences in the matching degree of grain production with water and soil resources.The matching degree of water and soil and that of water and grain is low in the main grain producing areas,which shows the characteristics of?more grain and less water?.From 2000 to 2017,the concentration of grain production in 13major grain producing provinces in China showed a continuous growth trend,but the water-grain matching coefficient showed a fluctuating downward trend,further indicating that the role of water resources in food production security in China continued to decline,and the mismatch between food production and water resources in China will become increasingly obvious in the future.The proportion of grain yield is positively correlated with the effective irrigation area,which shows that irrigation has a significant role in promoting grain yield,and improving the effective irrigation rate is an important way to ensure food security in China.Thirdly,the regional difference of water resources non-agricultural utilization level is obvious,the south area is higher than the north area,the central and eastern areas are higher than the west area,which is closely related to water resources endowment,urbanization and economic development level.The convergence test of non-agricultural utilization of water resources shows that there is no obvious?convergence trend at the national level,but absolute?convergence exists at the national and regional levels,which shows that assuming the same level of non-agricultural utilization of water resources,the internal differences of non-agricultural utilization of water resources in different regions will disappear automatically with the passage of time,which also shows that the non-agricultural utilization of water resources in different regions can maintain relatively synchronous growth.There are significant positive spatial autocorrelation and spatial agglomeration in the water resources non-agricultural degree of 31 provinces in China,which indicates that there are?high-high?and?low-low?aggregation patterns in the water resources non-agricultural level of all regions in China,and the geographical spatial distribution factors should be taken into account.After the study on spatial spillover effect of water resources'non-agriculturization in and between regions by selecting relevant variables,the results show that the direct effects of each factor in the province are mostly positive,the spillover effects between provinces are either positive or negative,and the significant total spatial effects of each factor are mostly positive,which indicates that the factors affecting the water resources'non-agriculturization are mutually constrained and driven,therefore cooperation among regions should be strengthened to form a benign competitive state.Fourthly,the efficiency of water use for grain production in China has not reached the optimal frontier,and there is still great potential for water conservation in grain production.The water use efficiency of grain production in most provinces is increasing,and the water resource efficiency of main grain producing areas is relatively high.According to the water use efficiency of grain production and the surplus of water in the process of grain production calculated by different regions,the utilization efficiency of water resources in grain production is closely related to the regional water resources endowment.The utilization efficiency of water resources in grain production in areas with abundant water resources needs to be improved,and the potential of water saving in grain production is huge.The total factor productivity of grain water use calculated based on the overall benchmark technology framework shows that technological progress has a greater driving effect on the growth of grain water use efficiency,and technology has become the leading factor restricting the improvement of grain water use efficiency in China.The renewal of agricultural irrigation equipment and technological improvement play a major role in the improvement of grain water use efficiency.The geographical weighted regression results of the factors influencing the efficiency of water use for grain production show that the regression coefficients of annual precipitation,the proportion of groundwater to the total water supply,the proportion of wheat planting area and the proportion of agricultural water use are all negative,the regression coefficients of effective irrigation area are positive,and the influence degree of each factor on different regions shows obvious spatial heterogeneity.Therefore,the appropriate measures should be taken in each region to improve the efficiency of water use in grain production,considering each region's local conditions.Fifthly,while the center of grain production in China is gradually moving from south to north,from east to central,the level of water resources'non-agricultural usage in the East,South,Beijing,Tianjin and other major non grain producing areas is gradually improving,the spatial evolution trend of water resources'non-agriculturization and the evolution of grain production center are in the reverse direction,so the negative impact of water resources non-agricultural on grain production is relieved.Water resources'non-agriculturization is an inevitable trend consistent with the development of social and economic level,but it has typical spatial heterogeneity and has different influence on grain production capacity in different regions.Therefore,strict control over the speed and quantity of water resources'conversion from agriculture to non-agricultural fields should be strengthened.At the same time,based on the pattern of grain production center and the principles of comparative advantage and space efficiency balance,Chinese government should optimize the spatial allocation of water resources,and broaden sources and reduce expenditure of water resources according to local conditions.