Study On Matching Of Agricultural Land And Water Resources In Henan Province From The Perspective Of Water Footprint

As a major grain producing province and a grain exporting province in China,Henan Province must not only stabilize China's food security,but also face the pressure of zero or even negative growth in agricultural water consumption.The contradiction of“grain increase and water reduction”will become more prominent.Therefore,studying the regional and structural differentiation characteristics of agricultural water and soil resources in Henan Province,finding out that the province's agricultural water and soil resources match the family,and providing a healthy and productive ecological environment for sustainable agricultural production is of great significance to guarantee the province's grain production capacity and the carrying capacity of land and water resources.Based on the above objectives,Henan Province was used as the research area,using the CROPWAT model and ArcGIS software,and statistical analysis methods and spatial analysis methods are mainly used for analysis.Firstly,according to the data of agricultural meteorology,soil,crops and agricultural production in Henan Province,the water footprint of agricultural production of main food crops in Henan Province was calculated and analyzed for its temporal and spatial variation characteristics.At the same time,the relationship between groundwater level changes and crop production is studied;Secondly,from the perspective of blue-green water,the study analyzes the agricultural water resources in Henan Province in a broad sense,and quantitatively evaluates the“blue water”resources and“green water”resources in various provinces.Next,the Gini coefficient and the agricultural water and soil resources matching model are used to compare and analyze the matching coefficient of agricultural land and water resources in the broad and narrow sense across the province;Finally,in view of the water and soil resource utilization problems in the research,the improvement and optimization measures for agricultural soil and water resources in Henan Province were proposed.Through the above research,the following main conclusions are obtained:(1)The water footprint and spatial variation characteristics of agricultural production of main food crops in Henan Province.The water footprint of wheat and corn was 0.89m~3/kg and 0.62m~3/kg between 2006 and 2015.In terms of interannual variation,the water footprint of wheat showed a decreasing trend;while the water footprint of corn was irregularly distributed,with large fluctuations during the interannual precipitation.In terms of spatial distribution characteristics,the high value cities and low value cities of the water footprint of wheat respectively form a significant agglomeration area;The water footprint of corn is more typical in the cities,and the aggregation between the zones is weaker than that of wheat.In terms of water consumption in crop production,the proportion of blue water footprint in the wheat is higher than that of corn.(2)The impact of groundwater level changes and crop production on groundwater in Henan Province.The groundwater level in the whole province has shown a downward trend.The center of the buried center centered on Zhengzhou is expanding,spreading from the northwest to the southeast.The maximum change in groundwater depth between 2006 and 2015 also occurred in Zhengzhou and surrounding cities.In the response analysis of groundwater depth to wheat and corn planting,the fourth-order partial correlation coefficient between precipitation and groundwater depth is-0.674,which is negatively correlated but the strongest correlation.The planting area and yield of wheat and corn were positively correlated with groundwater depth,but the crop planting area was weaker than crop yield.The fourth-order partial correlation coefficient between wheat,corn yield and groundwater depth was 0.515 and 0.563 respectively.(3)Matching status of agricultural and soil resources in general and narrow sense in Henan Province.The amount of general agricultural water resources in Henan Province is 491.22×10~8m~3,of which the effective precipitation of“green water”resources is 373.32×10~8m~3,accounting for 76%of the total;the amount of“blue water”resources is 117.90×10~8m~3,accounting for 24%of the total.The matching coefficients of general and narrow-scale agricultural land and water resources in the province are 3448m~3/hm~2 and 828m~3/hm~2,respectively.In the province's matching pattern,the overall north is better than the south,and the northern Henan region has the best matching pattern.(4)Suggestions for the rational allocation of agricultural land and water resources in the province.Firstly,the water resources will be effectively utilized to reduce the consumption of groundwater resources.Secondly,the efficiency of water production will be improved,and the water-saving production mode will be implemented.The agricultural planting structure will be adjusted again to optimize the crop layout.Finally,rationally control the groundwater exploitation,establish a reasonable system of cultivated land fallow rotation,and improve the quality of cultivated land.