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Tillage erosion: the principles, controlling factors and main implications for future research

Wysocka-Czubaszek A., Czubaszek R.

Journal of Ecological Engineering

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2014

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Vol. 15, nr 4

150--159

EN

Tillage erosion is one of the major contributors to landscape evolution in hummocky agricultural landscapes. This paper summarizes the available data describing tillage erosion caused by hand-held or other simple tillage implements as well as tools used in typical conventional agriculture in Europe and North America. Variations in equipment, tillage speed, depth and direction result in a wide range of soil translocation rates observed all over the world. The variety of tracers both physical and chemical gives a challenge to introduce the reliable model predicting tillage erosion, considering the number and type of tillage operation in the whole tillage sequence.

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Gullies development in afforested slopes in Southeastern Spain

Ruiz-Sinoga J. D., Romero-Díaz A., Belmonte-Serrato F., Alonso-Sarría F.

Landform Analysis

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2011

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Vol. 17

173-176

EN

In semiarid regions, the main purpose of afforestation has been to provide a protective vegetative cover in order to prevent or reduce soil erosion. This paper shows the results of a study carried out in some areas afforested in the 1970s, in steep slopes and mostly in marls. Afforestation where performed using terraced with subsoiling, so the existing scrub vegetation was removed and Pinus halepensis was planted. The main conclusion is that human action developed in this semi-arid territory, perhaps because the technique applied was not the most suitable for afforestation, has led to the geomorphological activation of the slopes and the emergence and large development of gullies.

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Cinder movement experiments on scoria cones slopes : Rates and direction of transport

Hooper D. M.

Landform Analysis

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1999

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Vol. 2

5--18

EN

As part of a field experiment to examine slope processes, four experimental grids with painted and numbered cinders were placed on the outer crater rims of two scoria cones in the San Francisco volcanic field, Arizona. Each grid contained 50 cinders placed in five rows of ten each. Rows were placed parallel to local slope contours. The mean diameter for each cinder was 1.7±0.2 cm (n = 200) and the average grid slope was 20.2°. Grids were set in July 1992. They were revisited one month later in August 1992 and again two years later in August 1994. Although several cinders failed to show any movement in the August 1992 survey, the average length of movement was 11.2 cm (n = 118). If the total movement is averaged over the 197 cinders that were relocated, the average length of movement then becomes 6.7 cm (n = 197). All cinders showed movement in the August 1994 survey and the average distance of movement was 32.8 cm (n= 141 with 59 missing cinders). The mean annual rate of movement after 25 months was 15.8cm/yr(n= 141). Using the convention that the 180° azimuth direction is downslope and perpendicular to local slope contours, the direction of cinder movement more closely approaches 180° with an increase in time. The azimuth directions calculated after just one month of emplacement display greater scatter and variability than the more correlated results measured after 25 months. The mean azimuth value after the 1992 survey was 163.6±54.2° (n= 118), while the mean azimuth after the 1994 survey was 177.9±20.7° (n = 141). Several painted cinders displayed upslope movement when the grids were first visited after one month. However, after two years the cumulative movement for every cinder was downslope from its original position. Non-channel overland flow is interpreted to be the primary erosional agent responsible for moving the cinders in the downhill direction. Rainsplash is interpreted to be responsible for moving the cinders in the upslope direction and is believed to be the major contributor to the variability in the azimuth measurements.