Chin J Plant Ecol ›› 2023, Vol. 47 ›› Issue (9): 1211-1224.DOI: 10.17521/cjpe.2022.0116

Special Issue: 生态遥感及应用

• Research Articles • Previous Articles     Next Articles

Comprehensive assessment of vegetation carbon use efficiency in southwestern China simulated by CMIP6 models

LI Bo-Xin, JIANG Chao*(), SUN Osbert Jianxin   

  1. School of Ecology and Nature Conservation, Beijing Forestry University, Beijing 100083, China
  • Received:2022-04-02 Accepted:2022-12-03 Online:2023-09-20 Published:2023-09-28
  • Contact: * JIANG Chao(
  • Supported by:
    National Natural Science Foundation of China(42175170)


Aims The southwestern China is a region with complex topography and diverse ecosystem and vegetation types. However, its role as an ecological barrier is being weakened by the effects of climate change and increasing pressure of human activities. This study examines the temporal dynamics of vegetation carbon use efficiency (CUE) in this region using the CMIP6 models, aiming to effectively reducing the uncertainties in prognostic results of future predictions.
Methods We used MODIS remote sensing data for the period 2001-2014 and simulations from 15 models in the Phase 6 of the Coupled Model Intercomparison Project (CMIP6), to determine the capability of the new generation models in simulating the seasonal and annual vegetation CUE in the southwestern China. The performance of the models was ranked based on the composite rating index (MR).
Important findings Most of the models used in this study underestimated the annual vegetation CUE, and their ability to simulate the spatial patterns in the trends of vegetation CUE is generally poor. However, some models performed relatively well in simulating the spatial distribution of multi-year average vegetation CUE; the top 1/3 tier included BCC-CSM2-MR, CMCC-ESM2, TaiESM, EC-Earth3-Veg and CAS-ESM2-0 in the order of performance. Among the seasons, the models best simulated the spatial distribution of vegetation CUE in summer, with better results from BCC-CSM2-MR, EC-Earth3-Veg, TaiESM, CMCC-ESM2 and CAS-ESM2-0. The simulation capability of the models for winter is second only to that for summer, and relatively poor for spring and autumn. Compared to the simulations by individual models, the multi-model ensemble mean (MME-S) reduced the uncertainties and exhibited a strong simulation capability, especially in the spatial distribution of vegetation CUE in local areas such as the Sichuan Basin. There was a lack of good simulation capability for the spatial distribution of vegetation CUE in Qingzang Plateau, Hengduan Mountains and other topographically complex areas. In general, before applying the CMIP6 models for regional vegetation CUE simulation, it is necessary to comprehensively evaluate the specific models from multiple perspectives to select the models with better simulation performance.

Key words: carbon use efficiency, CMIP6 models, MODIS, evaluation, southwestern China