基于CROPWAT模型的哈尔滨地区26年大豆生产水足迹变化研究

Research on Soybean Production Water Footprint Based on CROPWAT Model During Past 26 Years in Harbin

水足迹是大豆主产区作物生长期农业用水评价的新指标体系,为定量评价哈尔滨地区大豆生产水足迹组成及降雨年型对大豆生产的影响,利用CROPWAT模型计算哈尔滨1986-2011年26年间大豆生产水足迹,探讨不同降水年型大豆生产水足迹及其水足迹组成来源的变化规律,评价其与哈尔滨地区大豆种植面积和产量的关系。结果表明:26年间,大豆生产水足迹中,蓝水足迹和绿水足迹所占的比例不同,绿水足迹为0.12～0.29 m^3·kg^(-1),是大豆水足迹的主要组成部分;对比不同降水年型大豆生产水足迹组成,在欠水年型整体上存在着显著的蓝水集聚效应,出现蓝水的5个年份主要集中在欠水年区域,蓝水范围为0.017 4～0.048 2 m^3·kg^(-1),占水足迹9.52%～28.73%;1986-2011年水足迹整体呈递减趋势,即随着农业管理技术的提升,单位产量绿水消耗量在逐渐减少。丰水年和欠水年与平水年相比,有效降雨量与大豆单产拟合方程R^2较大,表明在雨量较大或较小时降水分布对产量影响效应关系更接近于二次函数。本研究结果能够为黑龙江大豆主产区水肥统筹管理提供依据。

Water footprint provides a new index system for evaluating agricultural water use during crop growth period in major soybean producing areas. In order to quantitatively evaluate the impact of water footprint composition and rainfall year types on soybean production, water footprint of soybeans in Harbin city(1986-2011) has been calculated using the CROPWAT model provided by FAO,through which the regulations changes of its composition distributed in different rainfall year type and the relationship between the footprint with soybean planting area/yields were investigated. The results showed that the components of soybean water footprint varied from 1986 to 2011. From the whole view, green water footprint took a large proportion in the total water footprint content, which ranged from 0.12 to 0.29 m^3·kg^-1;the agglomeration effect was found in water-deficient year type for blue water: The five years for containing the blue water were all belonging to the water-deficient year, and normal and rich years basically need no irrigation. The changes of water footprint from 1986 to 2011 showed the decreasing trend, the blue water ranged from 0.017 4 to 0.048 2 m^3·kg^-1, which accounted for 9.52% to 28.73% of water footprint. The index R2 of quadratic equations showed that the relationship between effective rainfall and soybean yield per unit in wet-and dry-year could be described with quadratic function. The results of this study can provide a basis for the overall management of water and fertilizer in the major soybean producing areas of Heilongjiang province.