南水北调中线工程水源地南阳市生态安全评价研究

Abstract

以南水北调中线工程水源地南阳市为研究区，结合统计数据与遥感数据，基于GIS平台和压力-状态-响应（Pressure-State-Response，PSR）模型，选取了16个关键指标，从生态压力、生态状态和生态响应3个方面构建了生态安全评价体系。对2000年、2010年和2015年南阳市-丹江口水库汇水区-水渠缓冲区3个维度的生态安全水平进行评价，并对其时空演变特征进行分析。结果表明：（1）2000年、2010年和2015年，南阳市生态安全指数（Ecological Security Index，ESI）均值分别为48.88、49.76、50.60，丹江口水库汇水区ESI均值分别为51.52、52.80、53.70，干渠周边ESI均值分别为47.98、49.57、51.02，均呈现缓慢增加的趋势，总体上南阳市生态安全水平有所改善。（2）从空间来看，南阳市生态安全水平总体上呈现出西北高、东南低的空间分布特征。2000—2015年，南阳市西部地区整体呈现增加趋势，而东部地区整体呈减小趋势。（3）南阳市各行政单元生态安全水平具有明显的区域差异。2000—2015年，ESI均值最大的是淅川县，最小的是新野县，处于一般安全的区县共6个，较低安全水平的县区共6个。淅川县、内乡县、邓州市和市辖区生态安全水平有所提高，社旗县生态安全水平明显下降。（4）南阳市生态安全水平与生态状态指标的相关性整体较高，与生态响应指标的相关性较低。研究结果可为南水北调水源区其他城市的生态安全建设和规划提供参考。;Combining the statistical data and the remote sensing data in Nanyang, China, the water source of the Middle Route Project of South-to-North Water Transfer, we selected 16 key indicators to construct ecological security assessment system from three aspects of ecological pressure, ecological status and ecological response.. This system was established by GIS platform and Pressure-State-Response (PSR) model. We evaluated the ecological safety level of the three dimensions of Nanyang City-Danjiangkou Reservoir Catchment Area-Water Canal Buffer Zone in 2000, 2010 and 2015, and analyzed its temporal and spatial evolution characteristics. Results showed:(1) In 2000, 2010 and 2015, the mean values of the Ecological Security Index (ESI) of Nanyang City were 48.88, 49.76, and 50.60, respectively. The mean values of ESI in the catchment area of the Danjiangkou Reservoir were 51.52, 52.80, and 53.70, respectively.The average ESI values of the buffer zone of main canal were 47.98, 49.57, 51.02. Resculs have shown a slow increase trend, and the overall ecological security level of Nanyang City has improved. (2) From a spatial perspective, the ecological security level of Nanyang City from 2000 to 2015 showed a trend of high in the northwest and low in the southeast. The western region of Nanyang showed an overall increasing trend, and the eastern showed a decreasing trend. (3) There are obvious regional differences in the ecological security level of various administrative units in Nanyang City. From 2000 to 2015, the largest average ESI was Xichuan County, and the smallest was Xinye County. There were 6 districts in general safety levels, and 6 districts in lower safety levels. The level of ecological security of Xichuan, Neixiang, Dengzhou and Nanyang city area have been significantly improved. The level of ecological security in Sheqi County has been significantly reduced. (4) The overall correlation between the ecological security level of Nanyang and the ecological status indicators is relatively high, but the correlation with the ecological response indicators is low. The research results can provide references for the ecological safety construction and planning of other cities in the water source area of the South-to-North Water Diversion.