Arid Zone Research ›› 2025, Vol. 42 ›› Issue (2): 299-311.doi: 10.13866/j.azr.2025.02.10

• Plant Ecology • Previous Articles     Next Articles

Spatiotemporal evolution of long-term vegetation NPP in Ordos based on GEE

LIU Ge1,2(), ZHAO Hengqian1,2(), HUANGFU Xiadan2, FU Hancong2, WANG Pan2, XU Fei2, HAN Tian2   

  1. 1. Inner Mongolia Research Institute, China University of Minning and Technology (Beijing), Ordos 017010, Inner Mongolia, China
    2. College of Geoscience and Surveying Engineering, China University of Minning and Technology (Beijing), Beijing 100083, China
  • Received:2024-07-14 Revised:2024-12-17 Online:2025-02-15 Published:2025-02-21
  • Contact: ZHAO Hengqian E-mail:lareinawl@163.com;zhaohq@cumtb.edu.cn

Abstract:

Utilizing the Google Earth Engine (GEE) cloud computing platform, the Net Primary Productivity (NPP) of Ordos was calculated based on an improved CASA model. Sen’s slope analysis and MK trend analysis methods were used to analyze the spatiotemporal changes in NPP from 2001 to 2020 and estimate the carbon sequestration capacity of Ordos City. (1) NPP in Ordos City displayed a significant seasonal variation from 2001 to 2020, with the highest values in July and August and an average annual NPP of 78.04 g C·m-2·a-1, following an overall fluctuating upward trend. (2) Spatially, NPP demonstrated clear heterogeneity, with higher values in the northeast and lower values in the northwest; high values were concentrated in Dalate Banner and Jungar Banner, while low values were mainly in Hanggin Banner. (3) The implementation of ecological projects and NPP changes were not fully synchronized, with a general trend of initially slow then accelerating growth; NPP change rates significantly increased after 2011 in most areas, but areas with harsher ecological conditions, such as Hanggin Banner, exhibited a lower improvement and some lag. (4) In 2011, Ordos displayed a widespread negative carbon sequestration rate. Yet, by 2020, the spatial heterogeneity in carbon sequestration had significantly increased, with higher values in the east and lower values in the west. The carbon sequestration capacity in Hanggin Banner’s western region still requires reinforcement, while Dalate Banner significantly improved its carbon sequestration capacity.

Key words: Ordos City, Google Earth Engine, CASA model, net primary productivity, carbon sequestration capacity