Agricultural Land Use Change And Its Impact On Agricultural Water Use In Hebei Plain

Food production is related to a series of major issues such as social development,national security and the sustainability of the ecological economy.The agricultural land use change and crop water consumption issues closely related to it are a major scientific issue in the overall strategy and academic research of the country.Hebei Plain as an important grain production in China,ensured national food security has become the primary task of regional development.However,due to the continuous changes in agricultural land use,the contradiction between agricultural water use and total water resources is prominent.In addition,the long-term unreasonable irrigation methods in the study area have intensified the contradiction between the two,and the severe shortage of water resources has become a major challenges and problems to be solved,therefore,a comprehensive and accurate analysis of the correlation between the main crop water consumption and crop planting space changes in the Hebei Plain has important practical significance for ensuring stable grain yield and sustainable use of agricultural water resources in the study area.In this paper,the Hebei Plain is used as a typical area for studying agricultural water-saving irrigation and agricultural land use.The main crops such as winter wheat,summer corn,spring corn,rice,fruit trees,cotton and vegetables in Hebei Plain in2002 and 2012 were selected to explore this time spatial and temporal variation of planting area,type and water consumption of main crops in the section.analyzing the driving factors of change,and estimating the water demand and water consumption of the main crops in the region by Penman-Monteith formula,and evaluating the effective precipitation and regional water balance.Based on the analysis,and from realizing the water-saving potential of farmland irrigation resources,the agricultural water-saving potential of Hebei Plain was comprehensively calculated,and further understanding of agricultural land use and agricultural water-saving irrigation in Hebei Plain.The following main conclusions are drawn:(1)From the spatial distribution and planting structure characteristics of crops in Hebei Plain,winter wheat-summer maize has the widest planting range,rice planting area is the least,and other crops are concentrated in different regions.Winter wheat increased 63,000 hm~2 from 2002 to 2012 in the eastern part of the study area.Summer corn increased by 132,000 hm~2 in the south,vegetables increased by 23,000 hm~2 in the east,and cotton increased by 70,000 hm~2 in the south.The planting area of rice and fruit trees decreased by 39,000 hm~2 and 120,000 hm~2,respectively.As a whole,most of the main crops in the Hebei Plain were increasing,and the planting area of a few crops was decreasing.(2)From the analysis of the impact of agricultural land use change on irrigation water,the total water consumption of winter wheat-summer maize increased by 220million m~3 and 11.3 m~3 respectively,the total water consumption of vegetables increased by 460 million m~3,and the total water consumption of cotton increased by910 million m~3,the total water consumption of rice decreased by 0.5 billion m~3,and the total water consumption of forest fruit decreased by 120 million m~3.As a result,the land use in the two periods has changed significantly,and the agricultural water consumption has also increased significantly.(3)The exploration of the agricultural water saving mode in the Hebei Plain has been studied.It is concluded that the local every three-year double cropping or once year cropping planting system is suitable.Appropriately reduce the cultivation of high-water-consumption crops,replace the economical water-saving crops,and adopt advanced water-saving technologies to achieve sustainable water-saving development in agriculture.