Abstract:

In order to qualitatively describe the soil relative humidity to be influenced by the cooperation with meteorological factors, and the agricultural drought and waterlog could be qualitatively evaluated, with 10 days average temperature, precipitation, evaporation and soil relative humidity (10-30 cm) data from 1994 to 2007 in Shuangyashan Region of Sanjiang Plain of Heilongjiang Province, based on grey correlation analysis, test and mathematical statistics method (CAR), the meteorological factors models of soil relative humidity were built. The results were shown: (1) the better correlativity was present between soil relative humidity and meteorological factors, the correlative prominent factors order was 10 days precipitation, ten days sun-shine, 10 days evaporation and ten days average air temperature, the important leading roles were precipitation and evaporation for soil relative humidity change, average air temperature and sun-shine impact on soil relative humidity by evaporation. (2) The model simulated effects were better, the physical significance of the model parameters was explicit, the impact were explained reasonably for soil relative humidity to be influenced by meteorological factor, at the same time, the impact degree under the cooperation with meteorological factors were described comprehensively and quantitatively for soil relative humidity. The simulated average error of soil relative humidity was 7.2% for 10-30 cm multilayer soil, the simulated effects were superior to 10 cm soil layer for 20 cm, 30 cm, and 10-30 cm average soil layer. The simulated effects of summer and autumn were superior to spring, but the one was good in May for crop sowing phase, the simulated error was 4.4%. The model could provide the reference for soil evaluation of drought and waterlog, agricultural disaster prevention and reduction in Heilongjiang Province.