基于动态当量的乐山市生态系统服务价值时空演变及驱动力研究

生态系统服务价值评估作为土地资源合理配置、生态环境保护和生态补偿标准制定的重要前提,是当前的研究热点之一。以乐山市为研究区域,基于2000年、2005年、2010年、2015年4期土地利用数据,运用生态系统服务价值动态当量法、地理探测器模型等方法,定量分析乐山市2000—2015年间生态系统服务价值时空变化规律及驱动机制。结果表明:(1)2000—2015年乐山市生态系统服务价值整体呈下降趋势,仅在2005—2010年有所回升,总量共减少了23.22亿元,主要与林地大量减少和建设用地大量增加有关;(2)空间上呈现西南高、东北低的分布态势,且各区域变化不同,西南方向山地以下降为主,东部平原丘陵以上升为主,河流两侧上升明显;(3)影响生态系统服务价值时空分布的主导因素为土地利用、NPP、降水量和坡度,除此之外气温、高程、土壤类型也有较大决定力;(4)自然因子决定力大于社会经济因子,但社会经济因子的影响越来越突出。研究揭示了乐山市生态系统服务价值的时空变化规律及驱动因子,为该地区土地利用规划与生态环境保护机制的建立提供了科学参考。

Evolution and driving force of ecosystem service value based on dynamic equivalent in Leshan City

As an important prerequisite for the reasonable allocation of land resources, ecological environment protection and the formulation of ecological compensation standards, evaluation of ecosystem services value is one of the current research hotspots. Taking Leshan City as the research area, based on the four periods of land use data in 2000, 2005, 2010, and 2015, the dynamic equivalent method of ecosystem service value was used to quantitatively analyze the temporal and spatial changes of ecosystem service value in Leshan City from 2000 to 2015. Based on the temporal and spatial heterogeneity of the ecosystem, this method combined the vegetation net primary productivity data, precipitation data and soil conservation data of Leshan City to dynamically correct the equivalent to make the results more accurate, spatial and comprehensive. Then, the geographic detector model was used to quantitatively detect the driving mechanism of the temporal and spatial changes of the ecosystem service value. The factor detector could detect the spatial correlation between driving factors and ecosystem service value. The interaction detector could evaluate whether the two factors worked together to increase or decrease the impact on the temporal and spatial distribution of ecosystem service value. And the ecological probes could compare whether there were significant differences in the impact of two factors on the temporal and spatial distribution of ecosystem service values.The results indicated that:(1) the ecosystem service value of Leshan City showed a downtrend from 2000 to 2015, and only rebounded from 2005 to 2010, with a total decrease of 2.322 billion yuan, which was mainly related to the massive reduction in forest land and the massive increase in construction land. (2) In terms of space, the distribution trend was high in the southwest and low in the northeast, and the changes in each region were different. The mountains in the southwest were mainly declining, the hills of the eastern plains were mainly rising, and the two sides of the river rose significantly. (3) The dominant factors affecting the temporal and spatial distribution of ecosystem service value were land use, vegetation net primary productivity (NPP), precipitation, and slope. In addition, temperature, elevation, and soil type also had a great effect. (4) The influence of natural factors was greater than that of social economic factors, but the influence of social economic factors was becoming more and more prominent. The study revealed the rule of temporal and spatial changes and driving factors of the ecosystem service value in Leshan City, and provided a scientific reference for the establishment of land use planning and ecological environment protection mechanisms in this area.