Semi-natural areas of Tarim Basin in northwest China: Linkage to desertification

Fang Liu; Hongqi Zhang; Yuanwei Qin; Jinwei Dong; Erqi Xu; Yang Yang; Geli Zhang; Xiangming Xiao

doi:10.1016/j.scitotenv.2016.07.180

Semi-natural areas of Tarim Basin in northwest China: Linkage to desertification

Sci Total Environ. 2016 Dec 15:573:178-188. doi: 10.1016/j.scitotenv.2016.07.180. Epub 2016 Aug 24.

Authors

Fang Liu¹, Hongqi Zhang², Yuanwei Qin³, Jinwei Dong³, Erqi Xu¹, Yang Yang⁴, Geli Zhang³, Xiangming Xiao³

Affiliations

¹ Key Laboratory of Land Surface Pattern and Simulation, Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing 100101, China.
² Key Laboratory of Land Surface Pattern and Simulation, Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing 100101, China. Electronic address: zhanghq@igsnrr.ac.cn.
³ Department of Microbiology and Plant Biology, Center for Spatial Analysis, University of Oklahoma, Norman, OK 73019, USA.
⁴ USDA-ARS Hydrology and Remote Sensing Laboratory, Beltsville, MD 20705, USA.

PMID: 27567388
DOI: 10.1016/j.scitotenv.2016.07.180

Abstract

Semi-natural lands are not intensively managed lands, which have ecological significance in protecting artificial oasis and preventing desertification in arid regions. The significant shrinkage and degradation of semi-natural lands in the land-use intensification process have caused severe desertification. However, there is a knowledge gap regarding the spatio-temporal pattern and detailed classification of semi-natural lands and its quantitative relationship with desertification. Taking the Tarim Basin as an example, we proposed a comprehensive classification system to identify semi-natural lands for 1990, 2000, and 2010, respectively, using multi-source datasets at large scales. Spatio-temporal changes of semi-natural lands were then characterized by map comparisons at decade intervals. Finally, statistical relationships between semi-natural lands and desertification were explored based on 241 watersheds. The area of semi-natural lands in Tarim Basin was 10.77×10⁴km² in 2010, and desert-vegetation type, native-oasis type, artificial-oasis type, saline type and wetland type accounted for 59.59%, 14.65%, 11.25%, 9.63% and 4.88% of the total area, respectively. A rapid loss of semi-natural lands (9769.05km²) was demonstrated from 1990 to 2010. In the fragile watersheds, the semi-natural lands were mainly converted to desert; while in the watersheds with advanced oasis agriculture, artificial-oasis type reclaimed to arable land was the major change. The occurrence of desertification was closely related to the type, area proportion and combination patterns of semi-natural lands. Desertification was prone to occur in regions abundant in desert-vegetation type and saline type, while less serious desertification was observed in regions with high proportion of artificial-oasis type and wetland type. Policy intervention and reasonable water resource allocation were encouraged to prevent the substantial loss of semi-natural lands, especially for the water-limiting watersheds and periods.

Keywords: Arid region; Desertification; Semi-natural lands; Sustainable development; Tarim Basin.