中国农业水资源压力测度与时空演进分析

Measurement and Spatial and Temporal Evolution Analysis of Agricultural Water Stress in China

为探究中国农业水资源压力的特征、时空分布格局以及演进规律,构建农业水资源压力指数模型测算全国各地农业水资源压力,并借助可视化工具分析时空分布格局,利用Dagum基尼系数分解、Kernel密度估计、Moran指数模型分析空间差异、动态演进和空间相关性规律。结果表明:①2005-2021年全国农业水资源压力指数从2.13下降至1.59,区域压力指数从高到低排序为东部>西部>中部>东北;②考察期内北京、天津、河北、山西、河南、山东、江苏、新疆、宁夏等九个地区压力指数均大于1,农业水资源压力指数大致呈“由北向南”、“由东北向西南”递减的空间分布规律;③Dagum分解结果显示,中国农业水资源压力的总体基尼系数仅有小幅下降,超变密度贡献率是总差异的主要来源;④Kernel密度估计呈现出“波峰减少,曲线向左运动,右尾缩短,宽度加大”的动态演进规律;⑤空间Moran指数从2014年开始显著为正,并且主要分布在第一、二、三象限。研究结论认为,虽然中国农业水资源压力指数呈下降态势但总体仍然偏大;农业水资源不可持续地区主要集聚在华北地区、环渤海经济区以及西北地区,区域间(内)压力指数呈明显的非均衡演进特征;农业水资源压力空间集聚特征主要呈现高高集聚(16.67%地区),低低集聚(50%地区)以及低高集聚(30%地区)三种模式。

In order to investigate the characteristics,spatial and temporal distribution patterns and evolution patterns of agricultural water stress in China,this paper constructs the agricultural water stress index model to measure the agricultural water stress across the country,and analyzes the spatial and temporal distribution patterns with the help of visualization tools,and analyzes the spatial differences,dynamic evolution and spatial correlation patterns by using the Dagum Gini coefficient decomposition,Kernel density estimation and Moran index model.The results show that:①the national agricultural water stress index decreased from 2.13 to 1.59 from 2005 to 2021,and the regional stress index ranked from high to low as east>west>central>northeast;②the stress index of nine regions,including Beijing,Tianjin,He⁃bei,Shanxi,Henan,Shandong,Jiangsu,Xinjiang and Ningxia,is greater than 1 during the period under examination,and the agricultural water stress index is roughly the spatial distribution pattern of decreases“from north to south”and“from northeast to southwest”;③Dagum decomposition results show that the overall Gini coefficient of China's agricultural water stress level only decreases slightly,and the contribu⁃tion of hypervariable density is the main source of the total difference;④The Kernel density estimates show a dynamic evolution pattern of“decreasing crest,moving to the left,shortening the right tail,and increasing the width”;⑤The spatial Moran index has been significantly positive since 2014,and is mainly distributed in the first,second,and third quadrants.The study concludes that although China’s agricul⁃tural water stress index is declining,it is still high overall;the unsustainable agricultural water resources are mainly concentrated in North China,Bohai Sea Economic Zone and Northwest China,and the inter-regional(intra-regional)stress index shows obvious unbalanced evo⁃lution characteristics;the spatial clustering characteristics of agricultural water stress mainly show high clustering(16.67%of areas),low clustering(50%of areas)and low spatial clustering(50%of areas).The spatial agglomeration of agricultural water resources pressure main⁃ly shows three patterns of high agglomeration(16.67%area),low agglomeration(50%area)and low agglomeration(30%area).