Evolution Law of Soil Fertility of Various Slopes in the Xiangjiaba Hydropower Project Area

Grey theory and Logistic equation were integrated in this paper to establish a structurally sound, explicit mentality and high-precision model for forecasting the future trend of main soil fertility, which provided us insight into artificial slops maintenance, at various substrates of slope in project area of Xiangjiaba Dam. Monitoring and sampling soil fertility factors in five types of slope from 2005 to 2014, and then analyzing the data by using Grey relational analysis and the model. The results are as follows, firstly, predictive modelling, which combines Grey theory and Logistic equation, is suitable for forecasting the soil fertility in project area of Xiangjiaba Dam. Secondly, the soil microbial biomass can represent the soil fertility level. The last one, during the period of 2005 to 2040, the fertility level in five different slopes' order is NF>VGCG>TLS>ESS>DR, and the VGCG slope's fertility level is the best among the artificial slopes, and this technique is worthy of popularization and application.