Micro-topography and soil physico-chemical properties of pastures on which parallel cattle tracks were formed
1997
Ishiwata, T. (Japan. Hokkaido Development Bureau, Sapporo) | Okita, Y. | Yokobori, M.
Characteristics of micro-topographic changes and soil physico-chemical properties accompanied with the formation of parallel cattle tracks were investigated in sloping pasture lands. 1. Where the grassland with a slope in the southeast direction became barren from cattle tracking, the surface soil was pushed to a lower position. In some instances, the soil accumulated in small mounds, leaving depressions on the uphill side. 2.The formation of mounds caused an increase in the height and steepness of the slope. This increase made it difficult for cattle to cross the mound. Thus, the cattle used only the existing tracks, thereby further exacerbating the problem. 3.The acreage ratios of the mounds, which were almost covered with heliophyte weeds, and cattle tracks, which were barren, ranged from 14 to 37% of the total pasture land area. This led to a lowering of the grazing capacity of the pasture land. 4. As the soil in the cattle tracks was compressed,coarse-size pore volume (CP) and easily-available water holding pore volume (EA) of the soil in the cattle tracks decreased to less than those of the original slope. Thus, the permeability of soil in the cattle tracks was low, and the cattle tracks became waterways when it rained. This caused soil erosion. On the other hand, bulk density of the soil was less, and COP and EA of the soil at mounds were larger than those of the original slope. 5. Nitrogen content, which can be extracted with hot water, and the available phosphorus content of soil in the cattle tracks were higher than those of the soil mounds. 6. The soil physico-chemical properties mentioned above are related to the formation of cattle tracks
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