Reduction of runoff and soil loss over steep slopes by using vetiver hedgerow systems

Abstract. A vegetation cover is found to be an ideal solution to most problems with erosion on steep slopes. Biodegradable geotextiles (GTX) have been proved to provide a sufficient protection against soil loss in the period before the vegetation reaches maturity. In this study, 500 g.m−2 jute (J500), 400 g.m−2 (C400), and 700 g.m−2 coir (C700) GTX were installed firstly on 9° slope in “no-inf iltration” laboratory conditions, secondly on 27° slope in natural field conditions. The impact of GTX on runoff and soil loss was investigated to compare the performance of GTX in different conditions. Laboratory runoff ratio (percentage portion of control plot) equaled 78 %, 83 % and 91 % and peak discharge ratio equaled 83 %, 91 % and 97 % for J500, C700 and C400, respectively. In the field, a runoff ratio of 31 %, 62 % and 79 % and peak discharge ratio of 37 %, 74 % and 87 % were recorded for C700, J500 and C400, respectively. All tested GTX significantly decreased soil erosion. The highest soil loss reduction in the field was observed for J500 (by 99.4%) followed by C700 (by 97.9%) and C400 (by 93.8%). Irrespective of slope gradient or experiment condition, C400 provided lower runoff volume and peak discharge control than J500 and C700. The performance ranking of J500 and C700 in the laboratory differed from the field, which may be explained by different slope gradient and also by the role of soil, which was not included in the laboratory experiment.

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Assessment of Improved Ladder Terraces in Controlling Soil Erosion on Uluguru Mountains-Tanzania

Journal of Agricultural Science ◽

10.5539/jas.v8n7p69 ◽

2016 ◽

Vol 8 (7) ◽

pp. 69

Author(s):

S. T. Materu

Keyword(s):

Soil Erosion ◽

Soil Loss ◽

Bare Soil ◽

Runoff Water ◽

Maize Crop ◽

Uluguru Mountains ◽

Percentage Weight ◽

Steep Slopes ◽

Runoff And Soil Loss ◽

Field Plots

<p>This study assesses effectiveness of improved ladder terraces in controlling soil erosion on steep slopes of Uluguru Mountains in Morogoro Region, where runoff collection tanks were located downstream of the divisor system were all runoff from the catchment upstream where improved ladder terraces were located. The soil properties percentage weight for sand, silt and clay were average 40, 10 and 50 respectively. Half of the terraces were left barely and half were planted with maize crop. Runoff and soil loss generated during every rainstorm was collected from six field plots of improved ladder terraces to the tanks. There was statistically significant different between reductions of soil loss in bare improved ladder terrace and cropped improved ladder terrace. The amount of runoff on the bare soil was high by 15% to 18% compare to runoff on cropped soils. It was found that cropped improved ladder terrace reduced soil loss by 74% while bare improved ladder terrace reduced soil loss only by 41%. Simple linear regression shows runoff water generated from rainfall amount with soil losses from different land cover. Bare soils behave with linear relationship (r² = 0.85) unlike cropped soil were r² = 0.36 because of gradual increase of crop canopy at every crop stage hence less impact to the soil. Soils losses from the bare soil ladder terrace and that of cropped soil ladder terrace was significantly difference with correlation coefficient of 0.863 at vegetative stage and 0.928 at the full booting stage.</p>

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Soil erosion in sloping vineyards under conventional and organic land use managements (Saar-Mosel Valley, Germany)

Cuadernos de Investigación Geográfica ◽

10.18172/cig.3161 ◽

2017 ◽

Vol 43 (1) ◽

pp. 119 ◽

Cited By ~ 31

Author(s):

M. Kirchhoff ◽

J. Rodrigo-Comino ◽

M. Seeger ◽

J.B. Ries

Keyword(s):

Soil Erosion ◽

Soil Loss ◽

Management Practices ◽

Conventional Tillage ◽

Erosion Processes ◽

Natural Rainfall ◽

Total Runoff ◽

Lack Of Information ◽

Steep Slopes ◽

Runoff And Soil Loss

German vineyards are one of the land uses most prone to soil erosion. Due to their placement on mainly steep slopes and non-conservative cultivation practices, runoff and soil loss are a serious problem for wine growers. In the Saar-Mosel valley (Rhineland-Palatinate, Germany), there is a tendency towards organic management of vineyards with protective grass cover in the inter-rows. Since there is a lack of information about organic-conventional tillage in German vineyards related to soil erosion processes, this study presents a comparison between these two soil management practices. For this purpose, 22 rainfall simulations were performed as well as a medium-term monitoring by using 4-paired Gerlach troughs in two experimental sites in the Saar-Mosel valley. The mean simulated runoff coefficient and suspended sediment load in conventional vineyards amounted up to 23.3% and 33.75 g m-2, respectively. In the organic site, runoff and soil loss were only recorded in one out of the 11 simulations. Runoff and sediment was collected in the Gerlach troughs for 33 natural rainfall events. In the conventional vineyard, the total measured soil loss was 3314.63 g m-1 and 6503.77 g m-1 and total runoff volumes were 105.52 L m-1 and 172.58 L m-1. In the organic site, total soil losses reached 143.16 g m-1 and 258.89 g m-1 and total runoff was 21.65 L m-1 and 12.69 L m-1. When soil loss was measured without corresponding runoff or precipitation, soil erosion was activated by tillage or trampling. Finally, the conventional vineyard showed a higher variability in soil loss and runoff suggesting less predictable results.

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ASSESSMENT OF SOIL EROSION IN VINH LINH, QUANG TRI USING RMMF MODEL (REVISED MORGAN - MORGAN - FINNEY)

HUE UNIVERSITY JOURNAL OF SCIENCE AGRICULTURE AND RURAL DEVELOPMENT ◽

10.26459/jard.v83i5.3083 ◽

2013 ◽

Vol 83 (5) ◽

Author(s):

Nguyễn Quang Việt ◽

Trương Đình Trọng ◽

Hồ Thị Nga

Keyword(s):

Soil Erosion ◽

Land Cover ◽

Soil Loss ◽

Soil Particle ◽

Transport Capacity ◽

Gis Technology ◽

Particle Detachment ◽

Sediment Transport Capacity ◽

Northern District ◽

Runoff And Soil Loss

Vinh Linh, the northern district of Quang Tri province is characterized by a diversified topography with a large variety of elevations, high rainfall, and decreasing land cover due to forest exploiting for cultivation land. Thus, there is a high risk of erosion, soil fertility washout. With the support of GIS technology, the authors used the rMMF model to measure soil erosion. The input data of model including 15 coefficients related to topography, soil properties, climate and land cover. The simulations of rMMF include estimates of rainfall energy, runoff, soil particle detachment by raindrop, soil particle detachment by runoff, sediment transport capacity of runoff and soil loss. The result showed that amount of soil loss in year is estimated to vary between 0 kg/m2 minimum and 149 kg/m2 maximum and is divided into 4-classes of erosion. Light class almost covers the region researched (75.9% of total area), while moderate class occupies 8.1% of total area, strong classes only hold small area (16% of total area). Therefore, protection of the forest floor in sloping areas is one of the most effective methods to reduce soil erosion.

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