基于退耕还林工程的生态环境质量动态变化研究—以云南兰坪县为例

2014年云南省怒江傈僳族自治州（简称怒江州）正式启动新一轮退耕还林还草工程，为探讨该轮退耕还林工程对怒江州兰坪白族普米族自治县（简称兰坪县）生态环境质量的影响，选择退耕还林工程实施前（2013年）、实施中（2017年）和实施末期（2020年）3个时间，基于遥感生态指数模型，选取绿度、干度、湿度和热度4个指标，运用主成分分析法对兰坪县2013—2020年的生态环境质量动态变化进行研究。结果表明：1）2013—2020年兰坪县生态环境质量处于上升趋势，中排乡、石登乡和河西乡的生态环境质量改善较为明显；2）2013—2020年，75%以上区域的生态环境质量等级保持不变，其他区域的生态环境质量等级呈小幅度变化，生态环境质量变好的区域面积要大于生态环境质量变差的区域面积；3）退耕还林斑块的生态环境质量提升程度要高于退耕还林2 km缓冲区以及整个研究区的生态环境质量提高程度，退耕还林工程对生态环境质量的改善具有显著影响，可通过进一步推进退耕还林工程来改善兰坪县的生态环境质量；4）研究区潜在的退耕区主要分布在中排乡、石登乡、营盘镇和兔峨乡4个乡镇，其可作为进一步退耕还林的重点区域。

Research on the dynamic changes of ecological environment quality based on the project of converting cropland to forest: taking Lanping County in Yunnan Province as an example

In 2014, Nujiang Lisu Autonomous Prefecture (Nujiang Prefecture for short) in Yunnan Province officially launched a new round of converting cropland to forest project. In order to explore the impact of the round of conversion of cropland to forest project on the quality of the ecological environment in Lanping Bai Pumi Autonomous County (Lanping County for short) in Nujiang Prefecture, three periods of time were selected: before the implementation of the project (2013), during the implementation of the project (2017), and at the end of the project (2020). Based on remote sensing ecological index (RSEI) model, four indexes, including greenness, dryness, wetness and heat, were selected and principal component analysis method adopted to study the dynamic changes of the ecological environment quality in Lanping County from 2013 to 2020. The results showed that: 1) The ecological environment quality of Lanping County had been on the rise from 2013 to 2020, and the ecological environment quality of Zhongpai Township, Shideng Township and Hexi Township improved significantly. 2) From 2013 to 2020, the ecological environment quality level of more than 75% of the regions had remained unchanged, and the ecological environment quality levels of other regions changed slightly. The area of better ecological environment was larger than the area of worse ecological environment. 3) The improvement degree of the ecological environment quality of the converting cropland to forest patches was higher than that of 2 km buffer zone of the converting cropland to forest project and the whole study area. The conversion of cropland to forest project had a significant impact on the improvement of the ecological environment quality. The ecological environment of Lanping County could be improved by further promoting the project of converting cropland to forest. 4) The potential abandoned farmlands in the study area were mainly distributed in the four townships of Zhongpai Township, Shideng Township, Yingpan Township and Tu'e Township, which could be used as key areas for further conversion of farmland to forests.armland to forests.