NDVI Variation and Its Responses to Climate Change on the Northern Loess Plateau of China from 1998 to 2012

Tingting Ning,Wen Lin,Wenzhao Liu,Xiaoqiang Song

doi:10.1155/2015/725427

Abstract

This study analyzed temporal and spatial changes of normalized difference vegetation index (NDVI) on the northern Loess Plateau and their correlation with climatic factors from 1998 to 2012. The possible impacts of human activities on the NDVI changes were also explored. The results showed that (1) the annual maximum NDVI showed an upward trend. The significantly increased NDVI and decreasing severe desertification areas demonstrate that the vegetation condition improved in this area. (2) Over the past decades, climate tended to be warmer and drier. However, the mean temperature significantly decreased and precipitation slightly increased from 1998 to 2012, especially in spring and summer, which was one of the major reasons for the increase in the annual maximum NDVI. Compared to temperature, vegetation was more sensitive to precipitation changes in this area. The NDVI and annual precipitation changes were highly synchronous over the first half of the year, while a 1-month time lag existed between the two variables during the second half of the year. (3) Positive human activities, including the “Grain for Green” program and successful environmental treatments at coal mining bases, were some of the other factors that improved the vegetation condition.

Highlights

Vegetation is the main component of terrestrial ecosystems on earth and plays an important role in the water, energy exchange, and biogeochemical cycles on terrestrial surfaces [1]
The normalized difference vegetation index (NDVI) has been frequently used for studying vegetation dynamics because it is highly correlated with the photosynthetic capacity, the leaf area index, biomass, and net primary productivity [7]
The lowest NDVI values were found in Jungar Banner, Ejin Horo Banner, and Wushen Banner in Inner Mongolia, as well as northern portions of Shaanxi province

Summary

Introduction

Vegetation is the main component of terrestrial ecosystems on earth and plays an important role in the water, energy exchange, and biogeochemical cycles on terrestrial surfaces [1]. Vegetation dynamics and the responses to climate changes have been recognized as one of the core issues of global change in terrestrial ecosystems [5]. The NDVI has been frequently used for studying vegetation dynamics because it is highly correlated with the photosynthetic capacity, the leaf area index, biomass, and net primary productivity [7]. The NDVI has been widely used to assess the net primary productivity of vegetation (NPP) [10, 11] and crop production [12, 13] and to indicate the feedback effects of vegetation on local climates [14,15,16]. The NDVI has been used to improve predictions and impact assessments related to disturbances, such as droughts [17] and floods [18]

Methods

Results

Conclusion