中国地理科学 ›› 2018, Vol. 28 ›› Issue (5): 784-796.doi: 10.1007/s11769-018-0967-1

• 论文 • 上一篇    下一篇

Drought Impacts on Vegetation Indices and Productivity of Terrestrial Ecosystems in Southwestern China During 2001-2012

ZHOU Lei1,2,3, WANG Shaoqiang2, CHI Yonggang1,2, WANG Junbang2   

  1. 1. College of Geography and Environmental Sciences, Zhejiang Normal University, Jinhua 321004, China;
    2. Key Laboratory of Eco-system Network Observation and Modelling, Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing 100101, China;
    3. School of Earth & Atmospheric Sciences, Georgia Institute of Technology, Atlanta 30332, USA
  • 收稿日期:2017-07-06 修回日期:2017-10-28 出版日期:2018-10-27 发布日期:2018-09-04
  • 通讯作者: ZHOU Lei. E-mail:zhoulei@igsnrr.ac.cn E-mail:zhoulei@igsnrr.ac.cn
  • 基金资助:

    Under the auspices of National Key Research and Development Program of China (No. 2016YFB0501501, 2017YFB0504000), National Natural Science Foundation of China (No. 41401110, 31400393)

Drought Impacts on Vegetation Indices and Productivity of Terrestrial Ecosystems in Southwestern China During 2001-2012

ZHOU Lei1,2,3, WANG Shaoqiang2, CHI Yonggang1,2, WANG Junbang2   

  1. 1. College of Geography and Environmental Sciences, Zhejiang Normal University, Jinhua 321004, China;
    2. Key Laboratory of Eco-system Network Observation and Modelling, Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing 100101, China;
    3. School of Earth & Atmospheric Sciences, Georgia Institute of Technology, Atlanta 30332, USA
  • Received:2017-07-06 Revised:2017-10-28 Online:2018-10-27 Published:2018-09-04
  • Contact: ZHOU Lei. E-mail:zhoulei@igsnrr.ac.cn E-mail:zhoulei@igsnrr.ac.cn
  • Supported by:

    Under the auspices of National Key Research and Development Program of China (No. 2016YFB0501501, 2017YFB0504000), National Natural Science Foundation of China (No. 41401110, 31400393)

摘要:

Drought, as a recurring extreme climate event, affects the structure, function, and process of terrestrial ecosystems. Despite the increasing occurrence and intensity of the drought in the past decade in Southwestern China, the impacts of continuous drought events on vegetation in this region remain unclear. During 2001-2012, Southwestern China experienced the severe drought events from 2009 to 2011. Our aim is to characterize drought conditions in the Southwestern China and explore the impacts on the vegetation condition and terrestrial ecosystem productivity. The Standardized Precipitation Index (SPI) was used to characterize drought area and intensity and a light-use efficiency model was used to explore the effect of drought on the terrestrial ecosystem productivity with Moderate Resolution Imaging Spectrometer (MODIS) data. The SPI captured the major drought events in Southwestern China during the study period, indicated that the 12-year period of this study included both ‘normal’ precipitation years and two severe drought events in 2009-2010 and 2011. Results showed that vegetation greenness (Normalized Difference Vegetation Index, NDVI and Enhanced Vegetation Index, EVI) both declined in 2009/2010 drought, but the 2011 drought resulted in less declines of vegetation greenness and productivity due to shorten drought duration and rising temperature. Meanwhile, it was about 5 months lapse between drought events and maximum declines in vegetation greenness for 2009/2010 drought events. In addition, forest, grassland and cropland revealed significant different ecosystem responses to drought. It indicated that grassland showed an early sensitivity to drought, while cropland was the most sensitive to water deficit and forest was more resilient to drought. This study suggests that it is necessary to detect the difference responses of ecosystem to drought in a regional area with satellite data and ecosystem model.

关键词: drought, Standardized Precipitation Index (SPI), vegetation indices, Net Primary Productivity (NPP), Southwestern China

Abstract:

Drought, as a recurring extreme climate event, affects the structure, function, and process of terrestrial ecosystems. Despite the increasing occurrence and intensity of the drought in the past decade in Southwestern China, the impacts of continuous drought events on vegetation in this region remain unclear. During 2001-2012, Southwestern China experienced the severe drought events from 2009 to 2011. Our aim is to characterize drought conditions in the Southwestern China and explore the impacts on the vegetation condition and terrestrial ecosystem productivity. The Standardized Precipitation Index (SPI) was used to characterize drought area and intensity and a light-use efficiency model was used to explore the effect of drought on the terrestrial ecosystem productivity with Moderate Resolution Imaging Spectrometer (MODIS) data. The SPI captured the major drought events in Southwestern China during the study period, indicated that the 12-year period of this study included both ‘normal’ precipitation years and two severe drought events in 2009-2010 and 2011. Results showed that vegetation greenness (Normalized Difference Vegetation Index, NDVI and Enhanced Vegetation Index, EVI) both declined in 2009/2010 drought, but the 2011 drought resulted in less declines of vegetation greenness and productivity due to shorten drought duration and rising temperature. Meanwhile, it was about 5 months lapse between drought events and maximum declines in vegetation greenness for 2009/2010 drought events. In addition, forest, grassland and cropland revealed significant different ecosystem responses to drought. It indicated that grassland showed an early sensitivity to drought, while cropland was the most sensitive to water deficit and forest was more resilient to drought. This study suggests that it is necessary to detect the difference responses of ecosystem to drought in a regional area with satellite data and ecosystem model.

Key words: drought, Standardized Precipitation Index (SPI), vegetation indices, Net Primary Productivity (NPP), Southwestern China