Analysis of desertification combating needs based on potential vegetation NDVI-A case in the Hotan Oasis

Lei Zhang; Jia Qu; Dongwei Gui; Qi Liu; Zeeshan Ahmed; Yi Liu; Zhiming Qi

doi:10.3389/fpls.2022.1036814

Analysis of desertification combating needs based on potential vegetation NDVI-A case in the Hotan Oasis

Front Plant Sci. 2022 Dec 14:13:1036814. doi: 10.3389/fpls.2022.1036814. eCollection 2022.

Authors

Lei Zhang^{1

2

3}, Jia Qu⁴, Dongwei Gui^{1

2}, Qi Liu¹, Zeeshan Ahmed^{1

2}, Yi Liu^{1

2}, Zhiming Qi⁵

Affiliations

¹ State Key Laboratory of Desert and Oasis Ecology, Xinjiang Institute of Ecology and Geography, Chinese Academy of Sciences, Urumqi, Xinjiang, China.
² Cele National Station of Observation and Research for Desert Grassland Ecosystem in Xinjiang, Cele, Xinjiang, China.
³ University of Cinese Academy of Sciences, Beijing, China.
⁴ Xinjiang University, Urumqi, Xinjiang, China.
⁵ McGill University, Department of Bioresource Engn, Saitne Anne De Bellevue, PQ, Canada.

Abstract

Combating desertification is vital for arresting land degradation and ensuring sustainable development of the global ecological environment. This study has analyzed the current desertification status and determined its control needs based on the difference between potential normalized difference vegetation index (PNDVI) and actual normalized difference vegetation index (ANDVI) in the Hotan desertoasis. The MaxEnt model, combined with the distribution point data of natural vegetation with long-term stable normalized difference vegetation index (NDVI) and 24 environmental factors was used to predict the PNDVI spatial distribution of different vegetation coverage grades and compared it with ANDVI. Excluding the areas of intense human activity such as arable land, the simulation results show that PNDVI with high, medium, and low vegetation cover was mainly distributed in the southwest and southeast of Hotan Oasis, in the midstream and downstream of Kalakash River and Yulong Kashi River, and the desert or Gobi area outside the oasis, respectively. The distribution of PNDVI with high, medium, and low vegetation cover accounted for 6.80%, 7.26%, and 9.17% of Hotan oasis, respectively. The comparison between ANDVI and PNDVI shows that 18.04% (ANDVI < PNDVI, about 3900 km²) of the study area is still suffering from desertification, which is mainly distributed in the desert-oasis ecotone in Hotan. The findings of this study implied that PNDVI could be used to assess the desertification status and endorsement of desertification control measures in vulnerable ecosystems. Hence, PNDVI can strengthen the desertification combating efforts at regional and global scales and may serve as a reference point for the policymakers and scientific community towards sustainable land development.

Keywords: desertification combating; maxent; over control; potential NDVI; potential natural vegetation.