交通对干草原土壤物理性质影响的试验研究

通过野外模拟实验，测定不同车速条件下草原交通便道相对起尘量，同时测定交通工具对草原土体结构的破坏，研究交通工具对干草原土壤物理性质的影响。研究结果表明，随着车速的增加，道路相对起尘量逐渐增加，且相对起尘量与车速之间呈现二次函数关系；在车轮的碾压作用下，土壤结构遭到破坏并形成直径在0．063～1．0mm之间的颗粒，随着碾压次数的增加，破碎颗粒的直径基本上都集中在0．125—0．18mm之间，且破碎土体总量也呈现增加趋势；车轮的碾压会导致土壤表面抗压强度增加，同时也使得土壤容重呈现增加趋势。

IMPACT OF TRAFFIC ON PHYSICAL PROPERTIES OF ARID GRASSLAND SOILS

Effects of traffic on soil properties are poorly understood, and very few methods are available for measurement of these effects. In this paper, dusting rate under vehicles different in velocity and destruction of structures of the soils were measured to explore impact of traffic on physical properties of soils of arid grasslands. Experiments were conducted with vehicle simulation under field conditions. These experiments involve four velocities (V=20, 30, 40, and 50 km h^-1), seven frequencies of crushing (0, 5, 10, 15, 20, 25 and 30 times) and four soil surfaces (heavily eroded land, mediumeroded land, newly eroded land and grassland). The results indicate that under the impact of wheels, soil structures would be destroyed forming soils particles 0.063~1.0 mm in size in the soil surface. With frequent crushing of wheels, soil particle sizes would vary in the range of 0.125~0.18 mm, and the amount of broken soil mass would increase. Also, the dusting rate would increase with the velocity of the vehicles, showing a quadratic function relationship. Moreover, vehicles could affect bulk density and compression strength of the soils, and they would increase with frequency of the compaction of wheels.