Location: Southwest Watershed Research CenterTitle: Natural and anthropogenic rates of soil erosion Author
|Xie, Y. - Beijing Normal University|
|Liu, B. - Beijing Normal University|
|Ye, Y. - Beijing Normal University|
Submitted to: International Soil and Water Conservation Research
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 4/10/2017
Publication Date: 4/18/2017
Citation: Nearing, M.A., Xie, Y., Liu, B., Ye, Y. 2017. Natural and anthropogenic rates of soil erosion. International Soil and Water Conservation Research. 5(2):77-84. https://doi.org/10.1016/j.iswcr.2017.04.001.
DOI: https://doi.org/10.1016/j.iswcr.2017.04.001 Interpretive Summary: Increases in human population have caused many areas of the world to undergo rapid changes from an essentially natural environment to one dominated by intensive agricultural. In this paper we discuss the transition from natural lands to intensive agricultural production lands. A short overview of natural, geologic rates of erosion is given, followed by the discussion of erosion trends in the transition to intensive agriculture. Examples are given for experiences in the United States, Northeastern China, the Brazilian Cerrado, Kazakhstan, and Europe. Results of this survey indicate that natural rates of erosion are very low, and generally in balance with natural rates of soil formation. Immediately after virgin land is brought into production the land typically experiences a phase of highly accelerated erosion because of the soil disturbance and the fact that some of the land is not suitable for agricultural production. After a period of time erosion rates decrease, but maintain levels much above what is sustainable. Introduction of conservation management practices, including conservation tillage and residue management, reduces erosion rates significantly. The use of no-till farming reduces rate of erosion in some cases to very low and sustainable levels. When cropland is taken out of production rates of erosion tend to return to their pre-agricultural erosion state.
Technical Abstract: Regions of land that are brought into crop production from native vegetation typically undergo a period of soil erosion instability, and long term erosion rates are greater than for natural lands as long as the land continues being used for crop production. Average rates of soil erosion under natural, non-cropped conditions have been documented to be less than 2 Mg ha-1 yr-1. On-site rates of erosion of lands under cultivation over large cropland areas, such as in the United States, have been documented to be on the order of 6 Mg ha-1 yr-1 or more. In northeastern China, lands that were brought into production during the last century are thought to have average rates of erosion over this large area of as much as 15 Mg ha-1 yr-1 or more. Broadly applied soil conservation practices, and in particular conservation tillage and no-till cropping, have been found to be effective in reducing rates of erosion, as was seen in the United States when the average rates of erosion on cropped lands decreased from on the order of 9 Mg ha-1 yr-1 to 6 or 7 Mg ha-1 yr-1 between 1982 and 2002, coincident with the widespread adoption of new conservation tillage and residue management practices. Taking cropped lands out of production and restoring them to perennial plant cover, as was done in areas of the United States under the Conservation Reserve Program, is thought to reduce average erosion rates to approximately 1 Mg ha-1 yr-1 or less on those lands.