EROSION CONTROL WITH GEOTEXTILES FROM NATURAL FIBERS IN THE MARGIN OF THE SÃO FRANCISCO RIVER

O baixo rio São Francisco foi impactado por mudanças no fluxo do rio causadas por políticas públicas implementadas nas últimas décadas causadas pela geração de energia elétrica. O objetivo deste trabalho foi avaliar o uso de geotêxteis fabricados a partir de fibras naturais no controle da erosão na margem do rio São Francisco. Geotêxtil , Syagrus coronata Geotêxtil e Bare Soil sem geotêxteis, localizado na margem direita do baixo rio São Francisco, no município de Amparo de São Francisco, estado de Sergipe, nordeste do Brasil. Entre os geotêxteis testados, os geotêxteis Syagrus coronata e Juncus sp foram temporalmente mais eficientes no controle da erosão, produzindo menor quantidade de sedimentos, embora na resistência e durabilidade das fibras, Typha latifolia apresentou melhores resultados.

Hydraulic Tests and Interpretation of Test Data for Reno Mattresses in Open Channel Flow

The efficacy of erosion control systems depends on preventing soil loss underneath and maintaining its integrity under the effects of the water flow. The paper presents the research results at the Colorado State University on the performance of double twisted wire mesh products, known as Reno Mattresses, used as soil erosion control systems. Mattresses were subjected to various flow conditions on a 10 m long flume placed on a soil layer. The performance against erosion was evaluated by assessing the effect of the stone motion inside the mattress combined with the condition of incipient soil erosion underneath, in relationship to the mattress thickness, the filling stone properties, and under variable hydraulic flow regimes. At the same time, confirming the stability obtained using the conventional tractive force design approach, the research results allowed to introduce a new performance limit based on incipient soil erosion underneath the revetment. Based on the research results, the authors propose to express the shear resistance of mattresses used as soil erosion control systems as a function of the filling stones’ size, uniformity, unit weight, mattress thickness, and the presence of vertical strengthening elements.

Assessment of NEWMAP Effects on Gully Erosion Control and Environmental Development over South East, Nigeria

The potential impacts of gully erosion over South Eastern Nigeria are a worrisome scenario. It has resulted in the displacement of millions of habitats, agricultural, and economic losses. The result of the effect of Nigerian Erosion Watershed Management Project (NEWMAP) monitoring and evaluation on the effect of gully erosion on economic development in this study has revealed a positive significant influence at P < 0.05 over the study region. Also, it is revealed that NEWMAP programmes have significantly covered some constructions of hydraulic structures for flood routing and soil erosion control in South East, Nigeria. This intervention has significantly reduced the rate of land degradation occasioned by soil erosion, protection of watershed and agricultural land, which has thus been responsible for improved agricultural production. In conclusion, it is imperative to conduct periodic monitoring and evaluation of the activities of NEWMAP to building a strong evidence-based mechanism that enhances assessment of the diverse range of intervention projects on the dwellers of South-East extraction.

Assessment of NEWMAP Effects on Gully Erosion Control and Environmental Development over South East, Nigeria

The potential impacts of gully erosion over South Eastern Nigeria are a worrisome scenario. It has resulted in the displacement of millions of habitats, agricultural, and economic losses. The result of the effect of Nigerian Erosion Watershed Management Project (NEWMAP) monitoring and evaluation on the effect of gully erosion on economic development in this study has revealed a positive significant influence at P < 0.05 over the study region. Also, it is revealed that NEWMAP programmes have significantly covered some constructions of hydraulic structures for flood routing and soil erosion control in South East, Nigeria. This intervention has significantly reduced the rate of land degradation occasioned by soil erosion, protection of watershed and agricultural land, which has thus been responsible for improved agricultural production. In conclusion, it is imperative to conduct periodic monitoring and evaluation of the activities of NEWMAP to building a strong evidence-based mechanism that enhances assessment of the diverse range of intervention projects on the dwellers of South-East extraction.