宁夏银川平原沙化土地不同人工林土壤质量评价

沙化土地土壤贫瘠、生产力低，人工植被恢复是重要的土壤改良措施。为研究宁夏银川平原沙地不同人工林栽植对土壤的影响，以银川腹部沙地银川植物园沙化土壤恢复区的2017年3月种植的文冠果(Xanthoceras sorbifolium)和欧李(Cerasus humilis)人工林地为研究对象，以邻近的长期撂荒地为对照，对土壤质量进行了研究。2020年7—8月采集土样并测定了土壤物理、化学、生物学等20个指标作为土壤质量评价的总数据集，方差分析筛选出差异显著性的9个指标作为重要数据集指标，采用主成分分析法和Norm值建立土壤质量评价指标最小数据集(MDS),利用线性和非线性两种评分方法计算土壤质量指数(SQI)。结果表明：与长期撂荒地相比，银川平原沙化土壤恢复区人工文冠果、欧李林地的土壤理化性质较好，土壤砂粒百分比减少、粉粒和黏粒百分比有所增加，pH降低；有机质、全氮、全磷、全钾等主要养分指标提高，蔗糖酶、脲酶、纤维素酶等主要生物酶活性也高于撂荒地，筛选出的研究区土壤质量评价MDS指标为土壤粉粒百分比和全磷。2种评价方法下，文冠果和欧李人工恢复林地的SQI高于撂荒地，但提高不显著(P>0...

Soil quality evaluation for different forest plantation of sandy land in Yinchuan Plain, Ningxia

Sandy land has poor soil and low productivity. Artificial vegetation restoration is an important measure for improving soil fertility and quality. Xanthoceras sorbifolium and Cerasus humilis are excellent drought-resistantly ecological tree species in Northwest, China. The effects of Xanthoceras sorbifolium and Cerasus humilis plantation, which were artificially cultivated in March 2017, had been evaluated in the sandy land of Yinchuan Plain, Ningxia, China, the neighboring long-term abandoned land as the contrast. Twenty soil physical, chemical and biological indicators were measured as the soil quality evaluation indicators of the total data set (TDS) in July to August 2020. Nine indicators were selected as soil quality evaluation indicators of significant data set (SDS) by variance difference significance analysis (ANOVA). The minimum data set (MDS) was constructed by principal component analysis (PCA) and the Norm value. Soil quality index (SQI) was calculated using linear (L) and non-linear (NL) scoring methods. The research results showed that the soil physical, chemical and biological properties of the Xanthoceras sorbifolium and Cerasus humilis plantation in the sandy soil restoration area of Yinchuan Plain were improved, comparing with the long-term abandoned land. The percentage of soil sand percentage (Sand) decreased, but the percentage of soil silt (Silt) and clay (Clay) increased, the pH decreased. The main soil nutrient indicators such as soil organic matter (TOC), total nitrogen (TN), total phosphorus (TP) and total potassium (TK) were improved, and the activities of major biological enzymes such as sucrase (SA), urease (UA) cellulase (CEA) and alkaline phosphatase (PPA) were also higher than CK. The MDS indicators for soil quality evaluation in the study area were Silt and total phosphorus (TP). Under the two evaluation methods, the soil quality indexes (SQIs) of the plantation of Xanthoceras sorbifolium and Cerasus humilis restored forest land were higher than the abandoned land, but the increase was not significant (P>0.05), and the soil quality index (SQI) of the Cerasus humilis forestland planted for 4a was higher than Xanthoceras sorbifolium forestland planted for 4 a (P>0.05). Compared with abandoned land, Xanthoceras sorbifolium and Cerasus humilis plantation can be cultivated and used as ecological restoration shrubs for soil improvement in this research area.There was significant (P<0.05) or extremely significant (P<0.01) correlation between the SQI calculated based on different data sets, the correlation coefficient between SQI-NLM and SQI-NLS was the largest. The nonlinear soil quality evaluation method based on MDS has better applicability in the study area and can represent the characteristics of soil quality more accurately. The soil quality evaluation method can be used as a reference for evaluating of sandy soil use quality in Yinchuan Plain, and for providing the reference of cultivation and management of Xanthoceras sorbifolium and Cerasus humilis plantation and the restoration of artificial vegetation in this area.