JU Zhansheng1, 2, Yang Qingsen3, XING Peiru4
(1. College of Geography and Environment, Baoji University of Arts and Sciences, Baoji Shaanxi 721013, China;
2. Shaanxi Key Laboratory of Disasters Monitoring & Mechanism Simulation, Baoji Shaanxi 721013, China;
3.Xi’an Research Institute of China Coal Research Institute, Xi’an 710054, China;
4. Fengxian People’s Government Office in Shaanxi Province, Fengxian Shaanxi 721700, China
Abstract: In order to generate information for monitoring spatial-temporal variations of the fractional vegetation coverage (FVC) in the headwaters of the Jialing river, the normalized difference vegetation index (NDVI) derived from Landsat remote sensing images (1987, 2000 and 2015 year) and the dimidiate pixel model were conducted in the Feng county of the Baoji city, Shaanxi province, using ENVI 5.3 and ArcGIS10.4 software. The results showed that: (1) the high vegetation coverage area had a dominant proportion and its area had increased by 5.96% from 1987-2015 in the study zone; (2) the vegetation coverage in 85.36% of the study zone was unchanged, and proportions of vegetation improvement area and vegetation degradation area in the study zone were 10.73% and 3.91%, respectively, the former was greater may be resulted from the effort of returning farmland to forest and grassland in the past 29 years; (3) as the slope angle and elevation increasing, FVC showed a variation pattern of starting with an increasing trend and then turning into decreasing, FVC of shady slope was slightly lower than that of sunny slope but higher than that of flatland, indicating that temperature played an important role in the influencing of the slope aspect to FVC; (4) the destructive effect of exploiting mineral resources to vegetation was worse than that of employing wind power plants, suggesting that the mine ecological environment restoration should be strengthened by the local government. This study is expected to be useful for ecological conservation and watershed management in the headwaters of the Jialing river.
Key words: fractional vegetation coverage (FVC); dimidiate pixel model; remote sensing and geographical information system; headwaters of the Jialing river; Feng county
EARTH AND ENVIRONMENT Vol.48, No.4, Tot No.336, 2020, Page 452-460