JOURNAL OF NATURAL RESOURCES ›› 2019, Vol. 34 ›› Issue (3): 624-632.doi: 10.31497/zrzyxb.20190315

• Resource Evaluation • Previous Articles     Next Articles

Spatiotemporal variation of vegetation in the lower reaches of Tarim River

GAO Qing1,2(), ALISHIR Kurban1(), XIAO Hao1,2   

  1. 1. Xinjiang Institute of Ecology and Geography, Chinese Academy of Sciences, Urumqi 830011, China
    2. Graduate University of Chinese Academy of Sciences, Beijing 100049, China
  • Received:2018-07-03 Revised:2018-10-25 Online:2019-03-28 Published:2019-03-28

Abstract:

To examine the spatiotemporal variation of vegetation in the lower reaches of the Tarim River, in this study, we use the cloud-free data of Landsat 5 TM and Landsat 8 OLI to obtain 22 time-series NDVI data during the period 1986-2017. We use the standard deviation of the NDVI time series to reflect vegetation change and the slope of linear regression equation of NDVI time series to reflect the variation tendency of vegetation. The results show that: (1) The distribution of vegetation is closely related to the distribution of water resources, mainly along the river channel and the water logged area. (2) For 1986-2000, the average NDVI value in the range within 1 km from the river channel fluctuated around 0.055, and showed a trend of slow decline because of the long-term absence of water supply. For 2000-2017, the average NDVI value showed an increasing trend and its fluctuation was closely related to volume and allocation of ecological water transportation. (3) The variance of NDVI time series in the study area was between 0.0077-0.1957, and there was obvious spatial difference. Its fluctuation was closely related to vegetation species. (4) The vegetation was in decline, which mainly occurred in the vicinity of Yingsu and old Yingsu during 1986-2000, but the vegetation mainly presented an increasing trend, and occurred mainly in the area along the river and east of Ka'erdayi during 2000-2017.

Key words: vegetation change, Landsat NDVI, time-series, lower reaches of the Tarim River, vegetation change, Landsat NDVI, time-series, lower reaches of the Tarim River