Microtopographic Erosion Features as Indicator of Erosion Hazard for Conservation Ad ice

摘要

Field observation of soil microtopography could distinguish seven types of features related to erosion. The features are: resisting clods, eroding clods, flow surfaces, prerills, rills, depressions and basal vegetal cover. In each of fifty tape intervals of 25 cm along the contour, the dominant feature is recorded. The feature record as a whole can be used to characterise the intensity of the erosion at the end of a rainy period. Thus different cropping systems can be compared for the erosion which they produce. A selection of the cultivation system that reduces erosion most effectively can be made in this way. Care should be taken that other erosion conditions are sufficiently similar, such as relief and rainfall. The method of recording soil surface features of microtopography is simple to learn, fast in operation, and cheap in execution. The feature recording can be done on whatever important types of land use exist in an area, such as annual and perennial crops, grassland, forest, orchard or plantation.