基于最小数据集的不同白及复合模式的土壤质量评价

[Objective]The soil quality index(SQI)of different intercropping models for Bletilla striata was evaluated to provide the theoretical basis for selecting suitable intercropping models and promoting understory bionomic cultivation.[Method]The experimental forests with different intercropping models were established in Guangde City,Anhui Province,China.three intercropping models of Phyllostachys edulis-Bletilla striata(BM),Platanus acerifolia-Bletilla striata(BX),and Carya cathayensis-Bletilla striata(BS)were selected,and the monoculture model of Bletilla striata(CK)was used as a control to assess the soil quality.A total of 16 soil indicators such as soil water content,organic carbon,and total nitrogen were measured in the 0-20 cm soil layer as the total data set(TDS)for soil quality evaluation,and the minimum data set(MDS)for soil quality evaluation indicators was established based on principal component analysis and Norm values.[Result]1)Soil water content,electrical conductivity,ammonium nitrogen,dissolved organic carbon,total nitrogen,total phosphorus,soil organic carbon,magnesium,microbial biomass carbon,and nitrogen content were significantly higher in BS than in CK(p<0.05).The dissolved organic carbon and nitrogen content and stable nitrogen isotopes were significantly lower in the intercropping models(BM and BX)(p<0.05).2)The indicators selected for MDS soil quality were pH,soil organic carbon,dissolved organic carbon,total phosphorus,and total potassium.3)The SQI ranged from 0.220～0.731,with the SQI of the intercropping model(BS)significantly higher than CK(p<0.01)and the SQI of BX significantly lower than CK(p<0.01).The linear relationship between the SQI of TDS and MDS(r = 0.824,p<0.01)was analyzed,indicating that the soil quality evaluation method of MDS has good applicability to evaluate the soil quality of intercropping model for Bletilla striata.[Conclusion]There were significant differences in the effects of different intercropping models,among which the intercropping model(BS)was significantly higher than the other models and CK in improving soil quality.Intercropping model(BS)has the meaning of guidance in the production practice of Bletilla striata and bionic cultivation.