Acta Geographica Sinica ›› 2016, Vol. 71 ›› Issue (5): 807-816.doi: 10.11821/dlxb201605009

• Ecology • Previous Articles     Next Articles

Validation of watershed soil effective depth based on water balance and its effect on simulation of land surface water-carbon flux

Richao HUANG(), Xi CHEN(), Yimeng SUN, Man GAO, Qinbo CHENG, Yongsheng ZHANG   

  1. State Key Laboratory of Hydrology-Water Resources and Hydraulic Engineering, Hohai University, Nanjing 210098, China
  • Received:2016-01-19 Revised:2016-03-24 Online:2016-05-25 Published:2016-05-25
  • Supported by:
    Key Project of National Natural Science Foundation of China, No.51190091


The soil effective depths are different due to regional features of various types of soils and vegetation, which impacts spatial and temporal distribution of soil moisture storage capacity and land surface water-carbon flux. In this study, the soil effective depth was calibrated using LPJ dynamic vegetation model on the target of remaining watershed water balance in three climate regions (Dongjiang River watershed in humid areas, Huaihe River watershed in humid, semi-humid areas and Jinghe River watershed in semi-humid and semi-arid areas). On this basis, we examined soil moisture storage capacity and land surface water-carbon flux (runoff R, actual evapotranspiration ET and net primary productivity NPP) resulting from variation of the soil effective depth. The results indicated that the estimated soil effective depth is 70 cm in the Dongjiang watershed, 90 cm in the Huaihe watershed and 140 cm in the Jinghe watershed. The soil effective depth and soil moisture storage capacity increase with the increase of drought degree. The correction of the soil effective depth in terms of water balance effectively reduces the simulation error, and affects the simulated results of the land surface water-carbon flux. However, the large or small effect is related to climatic conditions. The annual mean runoff and actual evapotranspiration change significantly in the humid areas, while the NPP changes significantly in the humid and semi-humid areas. The results provide a reference for improving the reliability of application of the LPJ model in different climate regions.

Key words: soil effective depth, soil moisture storage capacity, actual evapotranspiration, net primary productivity, dynamic vegetation model