With Tongxin, Xiji, and Longde counties in the mountainous area of southern Ningxia as the research area, we used extended-exergy analysis (EEA) to compare their ecological efficiency driving mechanism in 2008-2017 to explore the causes of their variation in ecological degradation. The results showed that the overall difference of ecological efficiency in the three counties was significant during the study period. The ecological efficiency of Tongxin was low, with large inter-annual variation. The ecological efficiency of Xiji was stable, and the overall efficiency of Longde was the highest. The difference of exergy scale was small among the three counties. The exergy proportion in the economic sectors was not coordinated, which were dominated by agricultural and residential sectors. The economic sectors presented significant capital-pull-type and labor-intensive characteristics, indicating the driving force for ecological degradation mainly came from agricultural production and residents' lives in underdeveloped regions. The system's internal exergy conversion rate and the external energy exchange rate of the three counties were extremely low, constituting a simple network circulation path with high input, low storage, low opening and low conversion, which weakened the endogenous development of social economic subsystem and threatened the fragile ecosystem.
以宁南山区3县(同心县、西吉县和隆德县)为研究区,运用扩展火用分析方法对比研究2008—2017年3县的生态效率驱动机制,探讨造成生态退化差异性的成因。结果表明: 研究期间,宁南山区3县整体生态效率差异显著,同心县生态效率偏低,年际变化幅度较大;西吉县生态效率较稳定;隆德县整体生态效率较高,位居三县首位。3县扩展火用规模整体差异较小,经济部门之间的火用比例不协调,均以农业部门、居民部门为主导,呈现显著的资本拉动型与劳动密集型特征,显现出欠发达地区生态退化的驱动力主要来源于农业生产与居民生活。3县系统内部的火用转化率与外界的能量交换率极低,形成了高输入、低储存、低开放和低转化的简单网络流通路径,削弱了社会经济子系统的内生发展能力,由此造成对本身就脆弱的生态系统的胁迫。.
Keywords: circulation path; driving mechanism; eco-efficiency; extended exergy analysis.