晋西南黄土高原区植被覆盖度变化及其生态效应评估

水土流失和生态退化是黄土高原区面临的严峻问题,已经严重制约了经济发展。基于TM和OLI数据,分别估算晋西南黄土高原区的植被覆盖度(FVC)和遥感生态指数(RSEI),定量分析了晋西南黄土高原区的植被和生态恢复效果,并提出需要重点治理的区域。研究结果表明:(1)15年间晋西南黄土高原区的植被覆盖度和遥感生态指数都呈现增加的趋势,FVC指数从2002年的42.69%增加至2017年的47.67%,RSEI指数由2002年的45%增加至2017年的52.5%,反映出研究区生态质量有了明显提高;(2)除研究区内芝河流域、汾河谷地和沁河流域的生态质量出现严重退化外,研究区大部分区域的FVC指数和RSEI指数都呈改善趋势,因此需对芝河流域、汾河谷地和沁河流域加大生态治理力度;(3)除研究区汾河谷地外,其余地区植被覆盖度和遥感生态指数的变化趋势基本吻合,汾河谷地由于冬小麦大面积种植,植被覆盖度得到一定程度改善,但遥感生态指数并没有明显改善。

Vegetation cover change and ecological effect assessment in the Loess Plateau of Southwest Shanxi province based on remote sensing image

Soil erosion and ecological degradation are serious problems for the Loess Plateau, which have seriously restricted economic development. Based on TM and OLI data, the FVC and RSEI in the Loess Plateau of Southwest Shanxi were estimated in this paper, and the effects of vegetation and ecological restoration were quantitatively analyzed. The results show that: (1) The index of FVC increased from 42.69% in 2002 to 47.67% in 2017, and the index of RSEI increased from 45% in 2002 to 52.5% in 2017, indicating a significant improvement of the ecological quality in the study area. (2) The ecological environment in most parts of the study area has been improved. Ecological degradation occurred in the Zhihe River Basin, Fenhe River Valley and Qinhe River Basin. (3) Due to the large-scale planting of winter wheat in the Fenhe River Valley, the index of FVC has been improved to some extent, but the index of RSEI has not been significantly improved. The variation trend of FVC and RSEI in other areas is basically consistent.