Coverage on soil could effectively decrease soilcontent on surface runoff.
地表覆盖能有效地降低地表径流中的泥沙含量；
2
According to the feature of gravel-soil, the water content of sample is controlled by granule soilcontent and sampled under the same vertical pressure.
结合碎石土的特点，采用细粒土含量控制试样的含水量，在同一竖向压力下制样。
3
Chronic simple silicosis has been reported to occur from environmental exposures to silica in regions with high silica soilcontent and frequent dust storms.