喀斯特石漠化区林草间作对土壤养分及微生物数量的影响OA北大核心CSTPCD

Forest-grass intercropping presents numerous advantages in terms of water conservation,soil fertility enhancement,and biodiversity promotion.This method can be used as a model for ecological restoration in Karst rocky desertification areas.To investigate the influence of forest-grass intercropping on soil nutrients and microbial populations in such regions,we anlayzed three planting patterns:intercropping of Zanthoxylum bungeanum with Dolichos lablab,intercropping of Z.bungeanum with Paspalum thunbergii,and sole monocropping of Z.bungeanum.This research was conducted at a long-term experimental base in Bangui Township,Guanling County,Guizhou Province.The results demonstrated that compared with Z.bungeanum monocropping,intercropping with D.lablab and P.thunbergii led to increases in organic matter,total nitrogen,fast-acting potassium,and alkaline nitrogen in the soil.Furthermore,the soil pH decreased,and the number of soil microorganisms,particularly fungi,significantly increased.The effective phosphorus content significantly decreased in the 0-10 cm soil layer,whereas it increased in the 10-20 cm soil layer.Correlation analysis revealed a significant negative correlation between the number of bacteria in the 0-10 cm soil layer and effective phosphorus,whereas the number of fungi and organic matter,total nitrogen,effective phosphorus,and pH were significantly positively correlated.In the 10-20 cm soil layer,the number of bacteria was significantly positively correlated with fast-acting potassium,whereas the number of fungi exhibited a significant negative correlation with pH.These findings suggest that the ecological restoration model of forest-grass intercropping,composed of Z.bungeanum and forage,has positive effects on soil nutrients and microbial populations in Karst rocky desertification areas.