山地乡村地表水资源二源耦合可达性评价——重庆市綦江区案例研究

EVALUATION OF COUPLED ACCESSIBILITY OF TWO SOURCES OF SURFACE WATER RESOURCES IN MOUNTAINOUS RURAL AREAS——A CASE STUDY OF QIJIANG DISTRICT, CHONGQING MUNICIPALITY

关键词:  地表水资源  可达性评价  山地乡村  二源耦合  重庆市綦江区

Key words:  surface water resources  accessibility evaluation  mountainous rural areas  two-source coupling  Qijiang district of Chongqing municipality

摘要:

目的 我国西南山地乡村的用水以地表水为主，探明山地乡村地表水的取水便捷度空间格局是建立其可持续发展框架的基础和前提。方法 文章以重庆市綦江乡村区域为例，利用河网、水库矢量数据、DEM、降水、土地利用栅格数据和库容统计数据等，采用改进CRITIC方法和综合叠加可达性评价模型，分析地表水资源的二源耦合可达性及其空间集聚特征。结果 （1） 373个样本乡村的二源耦合可达性平均值为0.58（最大值为1），52%乡村的可达性水平在0.58以上，其中可达性较好的（0.43~0.57，前47%分位点的数据）村庄有140个，占37.53%，可达性较差的（0.59~0.73，后47%分位点的数据）村庄有160个，占42.89%；（2）河流水源的可达性呈现北高南低、局部连片的格局，水库水源的可达性呈现中南部低、西北部高的格局，两者叠加后呈现出北高南低、聚集分布的格局；（3）河流水源和水库水源的可达性指数变化范围为0.19~0.88和0.15~0.89，对应的二源耦合可达性指数变化范围为0.21~0.86，不同取水可达性区域的占比显示，中等区域（45%~55%左右分位点的数据）占比最大，均值达到30%，极端情况（前40%或后40%左右分位点的数据）占比较少，均值仅为10%；（4）二源耦合可达性指数具有显著空间集聚特征，全局莫兰指数为0.62，其中高值聚集区（HH）集中在北部区域，低值聚集区（LL）集中在南部区域。结论 研究揭示了綦江区地表水资源供给能力的空间分异格局，可为乡村可持续发展与乡村振兴规划提供基础依据，经实地考察和专家咨询反馈结果表明，研究结果较为准确。

Abstract:

Surface water is the main water used in mountainous villages of Southwest China and it is the basis and premise to establish a sustainable development framework to find out the spatial pattern of water intake convenience of surface water in mountainous villages. Taking the rural area of Qijiang in Chongqing municipality as an example, this research used the river network, reservoir vector data, DEM, precipitation, land use grid data and storage capacity statistical data, etc., and adopted the improved CRITIC method and comprehensive overlay accessibility evaluation model to analyze two-source coupling accessibility of surface water resources and its spatial agglomeration characteristics. The results showed that: (1) The average accessibility of the two-source coupling accessibility of 373 sample villages was 0.58 (the maximum value was 1), and the accessibility level of 52% of the villages was above 0.58. Among them, there were 140 villages with good accessibility (0.43~0.57, data from the first 47% percentile), and there were 160 villages with poor accessibility (0.59~0.73, data from the last 47% percentile), accounting for 42.89%. (2) The accessibility of river water sources showed a pattern of high in the north and low in the south, and local contiguous areas. The accessibility of water sources of reservoirs presented a pattern of low in the central and south and high in the northwest. (3) The variation range of the accessibility index of river water source and reservoir water source was 0.19~0.88 and 0.15~0.89, and the corresponding variation range of the two-source coupling accessibility index was 0.21~0.86. The proportion of different water intake accessibility areas showed that, the middle area (data at the 45%~55% quantile point) accounted for the largest proportion, with an average of 30%, and the extreme cases (data at the first 40% or the last 40% of the quantile point) accounted for a small proportion, with an average of only 10%. (4) The two-source coupling accessibility index had significant spatial agglomeration characteristics, and the global Moran index was 0.62. The high-value cluster (HH) was concentrated in the northern region, and the low-value cluster (LL) was concentrated in the southern region. In summary, this study reveals the spatial differentiation pattern of surface water resource supply capacity in Qijiang District, and it can provide a basic basis for rural sustainable development and rural revitalization planning. The results of field investigation and expert consultation feedback show that the research are relatively accurate.