Journal of Geographical Sciences ›› 2017, Vol. 27 ›› Issue (2): 143-160.doi: 10.1007/s11442-017-1369-5

• Research Articles • Previous Articles     Next Articles

Correlation analysis between vegetation coverage and climate drought conditions in North China during 2001-2013

Zhaoning GONG(), Shuyi ZHAO, Jinzhi GU   

  1. Beijing Laboratory of Water Resources Security;Key Laboratory of 3D Information Acquisition and Application, Ministry of Education;Key Laboratory of Resources Environment and GIS of Beijing;College of Resource Environment & Tourism, Capital Normal University, Beijing 100048, China
  • Received:2016-08-26 Accepted:2016-10-09 Online:2017-04-10 Published:2018-01-05
  • About author:

    Author: Gong Zhaoning (1976-), PhD and Associate Professor, specialized in remote sensing for natural resources and environment. E-mail: gongzhn@163.com

  • Supported by:
    International Science & Technology Cooperation Program of China, No.2014DFA21620, The China Scholarship Fund

Abstract:

Climate change is one of the most important factors that affect vegetation distribution in North China. Among all climatic factors, drought is considered to have the most significant effect on the environment. Based on previous studies, the climate drought index can be used to assess the evolutionary trend of the ecological environment under various arid climatic conditions. It is necessary for us to further explore the relationship between vegetation coverage (index) and climate drought conditions. Therefore, in this study, based on MODIS-NDVI products and meteorological observation data, the Palmer Drought Severity Index (PDSI) and vegetation coverage in North China were first calculated. Then, the interannual variations of PDSI and vegetation coverage during 2001-2013 were analyzed using a Theil-Sen slope estimator. Finally, an ecoregion perspective of the correlation between them was discussed. The experimental results demonstrated that the PDSI index and vegetation coverage value varied over different ecoregions. During the period 2001-2013, vegetation coverage increased in the southern and northern mountains of North China, while it showed a decreasing trend in the Beijing-Tianjin-Tangshan City Circle area and suburban agricultural zone located in Hebei Province and Henan Province). Over 13 years, the climate of the northeastern part of North China became more humid, while in the southern part of North China, it tended to be dry. According to the correlation analysis results, 73.37% of North China showed a positive correlation between the vegetation coverage and climate drought index. A negative correlation was observed mainly in urban and suburban areas of Beijing, Tianjin, Hebei Province, and Henan Province. In most parts of North China, drought conditions in summer and autumn had a strong influence on vegetation coverage.

Key words: North China, vegetation coverage, PDSI, ecoregion, correlation analysis