不同水稳性团聚体测定方法的对比研究

水稳性团聚体是研究土壤肥力、质量及侵蚀强度的重要参考指标.研究目的不同,测定其含量的方法常常也不同.采用非真空快速浸润法、非真空快速滴水浸润法和非真空慢速气溶胶浸润法3种方法测定了黑土、褐土、黄土、红壤、紫色土共5种土壤的水稳性团聚体含量.通过配对样本t检验分析了各种方法的稳定性及不同方法的差异性.分析结果表明,非真空快速浸润法测定的各级团聚体含量和总含量均最小,非真空慢速气溶胶浸润法测定的各级团聚体含量和总含量均最大,非真空快速滴水浸润法则介于两者之间.分析了不同方法对团聚体的破坏机制及其适用范围,指出非真空快速浸润法、非真空快速滴水浸润法和非真空快速气溶胶浸润法对团聚体的破坏性呈减小趋势,它们分别适用于暴雨、中雨和小雨等情况.

Comparison of Different Pre-wetting Strategies in Wet Aggregate Stability Determination

Accurate determination of water-stable aggregates is of great significance for soil fertility,soilquality and soil erosion.Followed the three popular pre-wetting methods(no vacuum fast pre-wetting,novacuum fast dripping pre-wetting and no vacuum slow vapor pre-wetting),the contents of water-stable aggregates of 5soil types(black soil,cinnamon soil,loess soil,purple soil and red soil)were measured.Basedon paired-sample t tests,the results showed that the measured contents were fairly stable with the samemethod but varied substantially with different methods.The method of no vacuum fast pre-wetting generatedthe lowest values,no vacuum fast dripping pre-wetting the moderate,and no vacuum slow vapor pre-wettingthe highest,which might be suitable respectively for the conditions of heavy rain storms,moderate rain andgentle rain.