Chin J Plant Ecol ›› 2021, Vol. 45 ›› Issue (3): 213-223.DOI: 10.17521/cjpe.2020.0096

Special Issue: 青藏高原植物生态学:遥感生态学

• Research Articles •     Next Articles

NDVIdynamics and driving climatic factors in the Protected Zones for Ecological Functions in China

XU Guang-Lai1,2, LI Ai-Juan1,2, XU Xiao-Hua1,*(), YANG Xian-Cheng1,2, YANG Qiang-Qiang1,2   

  1. 1School of Geography and Tourism, Anhui Normal University, Wuhu, Anhui 241002, China
    2Anhui Key Laboratory of Natural Disaster Process and Prevention, Wuhu, Anhui 241002, China
  • Received:2020-04-07 Accepted:2020-06-03 Online:2021-03-20 Published:2021-05-17
  • Contact: XU Xiao-Hua
  • Supported by:
    National Natural Science Foundation of China(41301029)

Abstract:

Aims This study demonstrates the consistencies and discrepancies of correlations between climate factors and normalized difference vegetation index (NDVI) in the Protected Zones for Ecological Functions (EFPZs) in China, which provide useful information for monitoring in subsequent studies of vegetation dynamics.
Methods Based on the MODISNDVI data and the grid data for monthly precipitation and air temperatures from 2000 to 2015, the dynamics of NDVI and correlations with climatic factors were examined across 46 EFPZs at two spatial scales, by individual EFPZs and the pixels, using linear tendency and partial correlation methods. In accordance to the analyses, the EFPZs were categorized into different types of climatic influences.
Important findings The overall NDVI across the EFPZs showed an increasing trend, with the average linear slope of 0.045·a-1. Pixel scale analysis showed that NDVIincreased significantly in the central regions and the northeast of China. Partial correlation coefficients between NDVI and precipitation in the EFPZs varied between -0.30 to 0.72, and were positive for 32 in the EFPZs. Partial correlation between NDVI and air temperature ranged from -0.36 to 0.92, with positive correlations in 39 in the EFPZs. In 50.6% of the pixels, NDVIwas positively correlated with precipitation, mainly in northeast and northwest China. In 64.6% of the pixels,NDVI was positively correlated with air temperatures, mainly in the northeastern and the northern edge of the Qingzang Plateau. Strong temperature-precipitation driving is the main type of climatic influences on NDVI changes across the EFPZs, accounting for 38.7% of the total, with temperature driving type being secondary, accounting for 27.3%; non-climatic driving type accounts for 17.6%. Our results show the NDVI in the EFPZs are significantly correlated with climatic factors concerning precipitation and air temperatures, and that NDVI dynamics in 82.4% of the areas are driven by climate factors. Studying the changes in NDVI and the responses of NDVI to climate factors is very important for understanding the dynamics of vegetation in the EFPZs under climate warming.

Key words: the Protected Zones for Ecological Functions (EFPZs), normalized difference vegetation index (NDVI), climatic factor, partial correlation analysis, climate driving type zone