Study On Water Footprint Of Grain Production In Heilongjiang Reclamation Region

Our country is a large agricultural country, while the shortage of water resources is very serious in the country, how to improve the efficiency in the use of agricultural water resources and reduce its agricultural non-point source pollution harm, has a great important significance for easing the tension of the water resources and promoting the sustainable development of society and economy in China. Heilongjiang reclamation area is an important national commodity grain base, but uneven temporal and spatial distribution of water resources, the unreasonable water supply structure, low utilization efficiency, and coupled with the continuous drought in recent years, the phenomenon of water shortage is very serious, and the shortage of water resources has become a the main restriction factor of the sustainable development of economy and society in the Heilongjiang Reclamation area. The article from the research perspective of the production water footprint, drawing the algorithm of Aldaya (2008) about food production virtual water and applying the international research progress of gray water footprint(2010), by the CROPWAT8.0software provided by the United Nations FAO, have calculated the production water footprint of Rice Wheat Corn and Soybeans four kinds of crops to the nine branches of the Heilongjiang Reclamation area from2000to2009, and analyzed the characteristics of the spatial and temporal distribution of the four food crops water footprint and its impact factors.The results showed that:1.The blue water footprint of four crops of rice, spring wheat, corn and soybean have showed an overall declining trend (individual years have increased slightly somewhat); The green water footprint of three crops of rice, corn and soybeans have showed an overall the rising trend fluctuated in general while spring wheat shown a downward trend; The gray water footprint produced by application of Chemical fertilizers in the proportion of the total water footprint is large, rice, spring wheat, corn, soybean, gray water footprint of the four crops have showed an overall upward trend in general.2. From the temporal variation characteristics of water footprint, the change trend of the total water footprint of main food crops of the nine branches of the Heilongjiang Reclamation area keeps basically consistent with the change trend of crop sown area over time from2000to2009. Taking2003and2008as two turning points, the total water footprint of food crops has a significant downward trend from2000to2003, on a steady rise stage from2003to2008, and dropped slightly and tended to be stabilized in2009.From the spatial variation characteristics of water footprint, the Jiansanjiang branch has the highest total water footprint of food crops in food crops from2000to2009, Mudanjiang, Baoquanling Bei’an, Jiusan, these branches in the intermediate level has been adjusted somewhat in their spatial distribution pattern, the total water footprint of Harbin branch is always the lowest for its minimum cultivated area. In addition, the water footprint intensity of Heilongjiang reclamation area has declining trend the overall from2000to2009, five west branches and four east branches also showed the same downward trend, it is explained that water resource utilization efficiency has been improving. The whole spatial differences of the water footprint intensity in Heilongjiang reclamation area have related to the internal differences of regional development and the interval differences, The differences between groups of the five west branches and four east branches has the contribution to the whole spatial differences less than its internal differences.3. Through the correlation analysis, four kinds of crops, the green water, blue water and grey water footprint of these four kinds of crops all showed the significant correlation with their sown area, with blue footprint is concerned, it is more significant in sown area than in the effective irrigation area for the change of the blue water footprint, while effective precipitation and the blue water footprint showed negative correlation; To the green water footprint, it can much better reflect the change trend of green water footprint in sown area than rainfall and effective precipitation, it is not significant that the effective irrigation area and the total chemical fertilizer on green water footprint; To the gray water footprint, it is more significant influence of changes on sown area and the total amount of chemical fertilizer than precipitation, but the sown area has more significant influence on grey water footprint.