基于最小数据集的塔里木河上游绿洲土壤质量评价

QUALITY ASSESSMENT OF OASIS SOIL IN THE UPPER REACHES OF TARIM RIVER BASED ON MINIMUM DATA SET

以塔里木河上游绿洲阿拉尔垦区为靶区,综合考虑表征土壤物理、化学和生物学性质的14个土壤指标,利用数理统计方法确定最小数据集并评价土壤质量,同时与不含土壤酶指标的土壤质量评价结果进行对比分析。结果表明:(1)研究区土壤质量评价适用的最小数据集(MDS)包括:土壤水分、全盐、全氮和过氧化氢酶活性;(2)研究区棉田、新开垦农田、果园和林地等大部分耕地土壤质量属于中等及以上水平(SQI≧0.5的占78.12%),大部分分布于河岸及绿洲区域;(3)不包含土壤酶活性指标的土壤质量评价使土壤全盐含量的权重降低,且导致土壤质量评价结果偏低。

Soil quality assessment of the Aler oasis reclamation zone in the upper streams of the Tarim River was performed, taking into account integratedly 14 soil physico-chemical properties including soil water content, bulk density, pH, EC, total salt, organic matter, total N, alkalytic N, available P, available K, catalase, invertase, urease, and alkaline phosphatase, and using the minimum data set defined with the statistics method. And meanwhile comparative analysis was done of the soil quality assessment with the assessment without taking into account soil enzyme activity. Results show that （ 1 ） the minimum data set （ MDS ） suitable for use in the soil quality assessment of the oasis is composed of 4 indices, that is, soil water content, total salt, total N and catalase; （ 2 ） most of the cotton fields, newly reclaimed farmlands, orchards and woodlands, distributed in the riparian oasis region, are moderate or over in soil quality （SQI≥0.5 accounting for 78.12%） ; and （3） weight of total salt in the soil quality assessment without taking into account soil enzyme activity tends to be lower, which would lead to underassessment of the soil quality. This study may provide some references for regional soil resources utilization and decision-making for agricultural industry and ecological restoration.