Investigation of Ephemeral Gullies in Loessial Soils in Mississippi

摘要

Soil loss from agricultural fields due to the development of annual ephemeralgullies may equal or exceed the amount of soil loss from sheet and rill erosion. At the present, there are no widely used procedures for estimating the amount of soil loss produced by the annual development of ephemeral gullies. The purpose of this investigation was to obtain detailed data on the development of ephemeral gullies at four sites in west-central Mississippi over several years. The objectives of the study were to (1) establish four measurement sites in loessial soils, (2) develop an accurate and efficient procedure for measuring ephemeral gullies, (3) gather data which describes the development of the gullies through the cropping cycle, (4) provide additional estimates of the amount of soil loss in tons/ acre/year due to ephemeral gullies, and (5) provide recommendations on the use of the data and procedures for acquiring additional data. Gullies were measured in the field using the gulliometer for three cropping cycles during 1983-1985. A total of 1,350 gully cross-sections were measured in the field. Meteorological stations were also maintained at the sites during the period of measurement. Gullies were measured at site three photogrammetrically for the period 3 May 1985 to 13 January 1987. Field measurements reveal that although gullies typically go through periods of erosion and deposition during a cropping cycle, much of the linear development of the gully channel occurs within two months after planting during normal precipitation. After the crop is harvested, the gullies deepen over the fall and winter. Ephemeral gullies, Photogrammetry, Gulliometer, Soil erosion, Loessial soil, Soil measurement.