Evaluation of erosion control geotextiles on steep slopes. Part 1: Effects on runoff and soil loss

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

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.

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Evaluation of Different Best Management Practices for Erosion Control on Machine Operating Trails

Croatian journal of forest engineering ◽

10.5552/crojfe.2019.532 ◽

2019 ◽

Vol 40 (2) ◽

pp. 319-326

Author(s):

Ahmad Solgi ◽

Ramin Naghdi ◽

Eric R. Labelle ◽

Farshad Keivan Behjou ◽

Vahid Hemmati

Keyword(s):

Best Management Practices ◽

Soil Loss ◽

Management Practices ◽

Management Practice ◽

Erosion Control ◽

Forest Operations ◽

Best Management ◽

Negative Impacts ◽

Runoff And Soil Loss ◽

Final Selection

Ground-based mechanized forest operations often lead to increased runoff and soil loss on unbound forest roads and machine operating trails, which in turn can impede the technical trafficability of machines and cause negative impacts on the environment. The aim of this study was to evaluate the effectiveness of three Best Management Practice (BMP) treatments used to control erosion occurring on machine operating trails. The treatments included water bar, water bar and hardwood brush (H-brush), and water bar and softwood brush (S-brush). For a more comprehensive assessment of both brush treatments, two levels of brush thickness were tested; 0.5 m and 1.0 m. Results indicate that the most effective BMP treatments were the water bar and softwood brush followed by the water bar and hardwood brush and finally the least effective was the water bar. The average runoff rates and soil loss from the machine operating trails with the water bar treatment (52.64 l per plot, 8.49 g m-2) were higher than runoff and soil loss at the trails protected with hardwood brush (23.75 l per plot, 4.5 g m-2), and the trails protected by the hardwood brush had higher runoff and soil loss compared to trails covered by softwood brush (15.83 l per plot, 2.98 g m-2). Furthermore, results of this study showed that regardless of the treatment, the amount of runoff and soil loss decreased consistently as the thickness of the brush mat increased. Overall, erosion control techniques similar to either H-brush or S-brush that provide direct soil coverage should be used for erosion control, and final selection should be based on costs, availability of material, or landowner objectives.

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Comparison of different erosion control techniques in the Hyrcanian forest in northern Iran

Journal of Forest Science ◽

10.17221/121/2017-jfs ◽

2017 ◽

Vol 63 (No. 12) ◽

pp. 549-554 ◽

Cited By ~ 1

Author(s):

Masumian Ali ◽

Naghdi Ramin ◽

Zenner Eric K ◽

Nikooy Mehrdad ◽

Lotfalian Majid

Keyword(s):

Best Management Practices ◽

Soil Loss ◽

Management Practices ◽

Soil Cover ◽

Erosion Control ◽

Control Treatment ◽

Northern Iran ◽

Control Techniques ◽

Best Management ◽

Steep Slopes

The aim of this study was to evaluate the effects of closure best management practices (BMPs) on runoff volume and soil loss on skid trails that received two densities of soil cover mats and were located on two slope gradients in an Iranian temperate mountainous forest. The treatments included combinations of three closure BMPs (water bar only, water bar + sawdust, and water bar + hardwood slash), two amounts (densities) of mats (7.5 and 15 kg·m–2), and two levels of slope gradients (≤ 20% and > 20%). Results showed that the water bar treatment was the least effective erosion control treatment, followed by the hardwood slash and sawdust treatments. Averaged over mat densities and both slope gradients, the average runoff rates and amounts of soil loss from the skid trails with the water bar treatment were 46.7 l per plot and 6.1 g·m–2, respectively, 16.8 l per plot, 2.8 g·m–2, respectively, with the hardwood slash treatment and 11.7 l per plot, 1.9 g·m–2, respectively, with the sawdust treatment. The results indicated that surface cover is a necessary element for controlling erosion losses following a skidding disturbance, particularly on steep slopes.

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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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