Impacts of Chinese Grain for Green program and climate change on vegetation in the Loess Plateau during 1982-2015

Gang Li; Shaobo Sun; Jichang Han; Jianwu Yan; Wenbin Liu; Yang Wei; Nan Lu; Yingying Sun

doi:10.1016/j.scitotenv.2019.01.028

Impacts of Chinese Grain for Green program and climate change on vegetation in the Loess Plateau during 1982-2015

Sci Total Environ. 2019 Apr 10:660:177-187. doi: 10.1016/j.scitotenv.2019.01.028. Epub 2019 Jan 5.

Authors

Gang Li¹, Shaobo Sun², Jichang Han¹, Jianwu Yan³, Wenbin Liu⁴, Yang Wei¹, Nan Lu¹, Yingying Sun¹

Affiliations

¹ Shaanxi Provincial Land Engineering Construction Group Co., Ltd., Xi'an 710075, China; Key Laboratory of Degraded and Unused Land Consolidation Engineering, the Ministry of Land and Resources of China, Xi'an 710075, China; Shaanxi Provincial Land Construction Engineering Technology Research Center, Xi'an 710075, China; Institute of Land Engineering and Technology, Shaanxi Provincial Land Engineering Construction Group Co., Ltd., Xi'an 710075, China.
² Institute of Surface-Earth System Science, Tianjin University, Tianjin 300072, China. Electronic address: shaobo.sun@tju.edu.cn.
³ School of Geography and Tourism, Shaanxi Normal University, Xi'an 710119, China; National Demonstration Center for Experimental Geography Education, Shaanxi Normal University, Xi'an 710119, China.
⁴ Key Laboratory of Water Cycle and Related Land Surface Processes, Institute of Geographical Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing 100101, China.

PMID: 30640086
DOI: 10.1016/j.scitotenv.2019.01.028

Abstract

Remote sensing based vegetation index provides a practical method for the monitoring of vegetation dynamics at regional and global scales. Here, using a long-term remotely sensed normalized difference vegetation index (NDVI) dataset, we quantified the vegetation changes in the Loess Plateau (LP) over the last three decades (1982-2015), which includes the period before the Chinese"Grain for Green Program"(GGP) was launched (1982-1999), and the period after the GGP (1999-2015). The correlations between the NDVI and four climate related variables, i.e., precipitation, temperature, root-soil moisture (RSM), and a drought proxy-standardized evapotranspiration deficit index (SEDI), were also examined. The results indicated that, (i) the GGP strongly changed the vegetation in the LP. The growing-season mean NDVI (GSM-NDVI) and the annual mean NDVI (AM-NDVI) decreased slightly before the GGP launched in 1999, with slopes of -3.38×10^-3 and-8.00×10^-4year^-1, respectively. However, they showed slight and significant (p<0.05) increases after the GGP, with slopes of 4.75×10^-3 and 2.32×10^-3year^-1, respectively. (ii) Climate change (i.e., warming and drying) resulted in adverse effects on vegetation in the LP during the period before the GGP. However, the observed changes (i.e., wetting and reduced drought) exerted positive effects on the vegetation during the period after the GGP. (iii) Inter-annual variations of spatially averaged NDVI over the LP were primarily determined by RSM rather than any other climate related variables. In the southeastern LP, the inter-annual variation of GSM-NDVI was mainly determined by precipitation and SEDI, while the inter-annual variation of AM-NDVI was mainly caused by SEDI and RSM. Inter-annual variations of both GSM-NDVI and AM-NDVI were mainly determined by SEDI and RSM in the northwestern LP, and by temperature in the southwestern LP.

Keywords: Climate change; Drought; Grain for Green Program (GGP); Loess Plateau; Normalized difference vegetation index (NDVI); Remote sensing.

MeSH terms

Agriculture / methods*
Biota*
China
Climate Change*
Environmental Monitoring*
Grassland*
Plants*