They call it the sustainable rate that degradation can occur in order for the system to remain stable. According to them erosion rates in the US are 17.0 ton. Based on these five factors, soils differ across continents, and are classified according to these properties of the soils as they occur in the field. The quality of soil is evaluated based on these and other variable characteristics which relate to it s productive capabilities. Soil texture refers to the size of the mineral particles.
Soil structure refers to the aggregation of the soil particles into large groups or aggregates.
Soil porosity is the volume of pores in a soil sample divided by the bulk volume of the sample. Although precise definitions of soil quality standards vary, most consider the ability of a soil to produce now and continue into the future an essential element. Measuring soil degradation is an inverse way of measuring soil quality. We can evaluate soil degradation in social or biophysical terms. The biophysical factors listed above are physically related to the soil itself.