关键词: 黄土高原, SWUF模型, 土壤水分, 水土保持林, 次生林

Abstract:

Study on soil water is crucial to construction and management of the water and soil conservation forests on the Loess Plateau. Dynamics of soil water from the 0-150 cm layers in three types of forests ( Robinia pseudoacacia and Pinus tabulaeformis (on a terraced field) plantations, and a naturally regenerated secondary forest) were monitored in this study with an EnviroSMART monitoring system (from 2008-05-14 to 2008-10-11 and from 2009-05-09 to 2009-08-08). The collected data were used to analyze the sensitivity and calibrate parameters of SWUF model, and this paper evaluated the applicability of SWUF model on hilly Loess Plateau in western of Shanxi Province. The results revealed that the simulated soil moisture was considerably sensitive to evaporation parameter, runoff parameter, and unsaturated flow parameters. Calibration of these parameters is necessary to apply SWUF model in this study area. The SWUF well simulated the daily average soil water content of each layer from 20－150 cm depth in R. pseudoacacia plantation and from 0－150 cm depth in P. tabulaeformis plantation and the secondary forest and the absolute relative error (ARE) of the simulated values was lower than 20%. The results indicated that SWUF could be used to simulate the daily soil water dynamics in P. tabulaeformis plantation and the secondary forest. However, modification is needed to model soil water of 0－40 cm layers in R. pseudoacacia plantation due to rapid depletion in the soil water.

Key words: Loess Plateau, SWUF, soil water, soil and water conservation forest, secondary forest