筛分法是国内外广泛应用的土壤干团聚体粒径分布（Dry Aggregate Size Distribution，DASD）测定方法，但目前关于筛分时间和振幅这两项重要的筛分参数尚无一致标准。本研究以中国北方风蚀区9个主要土壤类型为研究对象，使用筛分法分析0.5、1.5和2.5 mm振幅条件下各土壤类型在筛分5、10、15、20、30、40和60 min后的DASD及平均重量直径（Mean Weight Diameter，MWD），并在此基础上确定9种土壤的最佳筛分参数。结果表明，受有机质及CaCO₃含量影响，自东向西，土壤团聚体主要粒级呈先减小后增大的趋势。随着筛分振幅和时间的增加，各土壤均呈较大粒级团聚体含量减少、较小粒级含量增多的趋势，但主要变化粒级及幅度因土壤类型而异。各土壤的最佳筛分振幅为1.5 mm，最佳筛分时间介于15-40 min之间。该结果为我国北方风蚀区土壤团聚体粒径分布测定提供参考依据之余，也为不同土壤DASD提供了比较基础。

Dry sieving is a widely used method for the determination of soil dry aggregate size distribution (DASD) worldwide. However, no agreement has been reached on the two important parameters of sieving time and amplitude, so far. In the current study, three sieving amplitudes of 0.5, 1.5 and 2.5 mm, and seven sieving durations of 5, 10, 15, 20, 30, 40 and 60 min, were employed to analyze their impacts on DASD and the corresponding mean weight diameter (MWD) of 9 major soil types in the wind erosion region of Northern China. Furthermore, the appropriate sieving amplitude and duration were determined for these 9 soils. The results show that the dominant size classes generally increased from the east to the west of the wind erosion region, followed by a decreasing trend, which was mainly regulated by the contents of two aggregate binding agents, i.e., soil organic matter and CaCO₃. With the increase of either sieving time or amplitude, the fractions of relatively larger aggregates usually decreased, accompanied by the mass percentage increases of smaller aggregates. But the size classes exhibiting apparent fraction changes varied among soils. The sieving amplitude of 1.5 mm was appropriate for the 9 soils in the wind erosion region; whereas, the suitable sieving durations ranged from 15 to 40 min. These findings not only hold important implications for soil DASD determination in the wind erosion region of Northern China, but also enable the DASD comparison among different soils.