Geohydrological study of the Vaal River north bank for the design of water conservation and seepage control measures

2020 ◽  
Vol 38 (5) ◽  
pp. 5667-5680
Author(s):  
Ali Torabi Haghighi ◽  
Anne Tuomela ◽  
Ali Akbar Hekmatzadeh

Water ◽  
2018 ◽  
Vol 11 (1) ◽  
pp. 20 ◽  
Author(s):  
Yaping Wang ◽  
Wenzhao Liu ◽  
Gang Li ◽  
Weiming Yan ◽  
Guangyao Gao

The tableland-gully region is one of the main topographic-ecological units in the Chinese Loess Plateau (CLP), and the soil in this region suffers from serious water erosion. In recent years, much work has been conducted to control soil erosion in this area. This paper summarized the development of soil and water conservation researches in the CLP from the bibliometric perspective based on the Science Citation Index (SCI) and Chinese National Knowledge Infrastructure (CNKI) databases. The quantity of SCI literatures has increased rapidly since 2007, with an average annual growth rate of 21.4%, and the quantity of CNKI literatures in the last decade accounted for 62% of the past 30 years. The development trends showed that early SCI research was related to loess geology in the context of ecological remediation, while the CNKI literature focused on agricultural production under comprehensive management. Over time, the research themes of the two databases gradually became unified, i.e., the management of sloping farmland and the improvement of agricultural productivity. Subsequently, the themes gradually extended to the disposition of comprehensive control measures for soil erosion and the environmental effect of agro-fruit ecosystems. The highly cited papers mainly focused on soil reservoir reconstruction, soil erosion factors, and environmental effects of vegetation restoration. Two aspects need further study, including (i) the effect of soil erosion control under different ecological remediation patterns; and, (ii) the ecosystem maintenance mechanism and regulation approaches that are based on the sustainable utilization of soil and water resources in the tableland-gully region of the Loess Plateau.


2020 ◽  
Author(s):  
Silvia Vacula ◽  
Lilian Niacsu ◽  
Cristian Secu ◽  
Ionut Vasiliniuc

<div>Land degradation by geomorphological processes (soil erosion, gully erosion, landslides and</div><div>sedimentation) represents an important environmental threat all over the Republic of Moldova.</div><div>The main causes are related to the favourable natural conditions such as friable lithology,</div><div>typically hilly fragmentation or climatic aggressiveness on the background of a sustained human</div><div>impact developed in the last two centuries. Despite the widespread soil and water conservation</div><div>measures that have been implemented during the soviet period, following the Agricultural Real</div><div>Estate Act applied in 1991, a revival of these processes is easier to observe especially by means</div><div>of floodplains aggradation. Under these circumstances, our study aims to assess the</div><div>sedimentation rates on the floodplains and reservoirs and to establish the source area of the</div><div>eroded sediments as well as the responsible process. Based on field campaigns, we took</div><div>representative in-situ soil / sediment samples from floodplains and reservoirs all over the Sarata</div><div>catchment, including wind-blown samples from the intefluvial ridges. The laboratory analyses</div><div>consisted of physical and chemical features such as: weight, apparent density, texture, ph,</div><div>electrical conductibility, total organic carbon, inorganic carbon, organic matter, inorganic</div><div>nitrogen (N), total phosphorus (P), total potassium (K) and other macro elements (i.e. Na+,</div><div>Mg2+, Ca2+, and Cl-). The preliminary results show that the soil erosion remains an important</div><div>process not by quantity but by quality. This is related also to the widespread high efficiency of</div><div>gully erosion control measures that have been implemented. A secondary role, most often</div><div>neglected, is held by wind erosion</div>


2021 ◽  
Vol 13 (16) ◽  
pp. 9276
Author(s):  
Nareth Nut ◽  
Machito Mihara ◽  
Jaehak Jeong ◽  
Bunthan Ngo ◽  
Gilbert Sigua ◽  
...  

Agricultural expansion and urban development without proper soil erosion control measures have become major environmental problems in Cambodia. Due to a high population growth rate and increased economic activities, land use and land cover (LULC) changes will cause environmental disturbances, particularly soil erosion. This research aimed to estimate total amounts of soil loss using the Revised Universal Soil Loss Equation (RUSLE) model within a Geographic Information System (GIS) environment. LULC maps of Japan International Cooperation Agency (JICA) 2002 and Mekong River Commission (MRC) 2015 were used to evaluate the impact of LULC on soil erosion loss in Stung Sangkae catchment. LULC dynamics for the study periods in Stung Sangkae catchment showed that the catchment experienced a rapid conversion of forests to paddy rice fields and other croplands. The results indicated that the average soil loss from the catchment was 3.1 and 7.6 t/ha/y for the 2002 and 2015 periods, respectively. The estimated total soil loss in the 2002 and 2015 periods was 1.9 million t/y and 4.5 million t/y, respectively. The soil erosion was accelerated by steep slopes combined with the high velocity and erosivity of stormwater runoff. The spatial distribution of soil loss showed that the highest value (14.3 to 62.9 t/ha/y) was recorded in the central, southwestern and upland parts of the catchment. It is recommended that priority should be given to erosion hot spot areas, and appropriate soil and water conservation practices should be adopted to restore degraded lands.


1970 ◽  
Vol 7 ◽  
pp. 35-42 ◽  
Author(s):  
Asheshwor Man Shrestha

Severe potential climate threats for Nepal are expected to impact water resource, agriculture, biodiversity and livelihood. While adaptation and mitigation are both valid policy options to tackle climate change, it is advantageous for developing countries to opt for adaptation. It is also desirable that the most feasible adaptation actions be applied to protect development investment from climate risks and to ensure maximum preparedness. Adaptation strategies consist of a set of measures that are highly effective, affordable, technically and socially feasible and contribute towards disaster risk reduction. An evaluative framework using scoring matrix is utilized to prioritize adaptation options. Adaptation options for threat areas identified for Nepal are analyzed based on literature in the context of Nepal as well as for Asia and for least developed countries (LDCs). The measures are evaluated across multiple categories like public/private costs, effectiveness, social/cultural feasibility, speed, support for mitigation and aid in disaster preparedness. Based on the scoring matrix evaluation, following measures appear most feasible: (1) water conservation and management; (2) investment in smaller hydro-power plants; (3) research/planting of climate resistant crops; (4) diversification of agriculture; (5) development of early warning system for disasters; and (6) flood control measures downstream. Due to financial and technical constraints, it is advantageous to opt for ‘no-regrets’ strategies which benefit even without climate change. These set of measures can be carried out at low costs to reap sure benefits and should be prioritized for execution through environmental policies especially climate policies. Key-words: Adaptation; climate change; climate policy; disaster risk reduction; Nepal. DOI: 10.3126/botor.v7i0.4371Botanica Orientalis – Journal of Plant Science (2010) 7: 35-42


2013 ◽  
Vol 14 (2) ◽  
pp. 283-290 ◽  
Author(s):  
Corinne E. Wilson ◽  
William F. Hunt ◽  
Ryan J. Winston ◽  
Patrick Smith

Low Impact Development (LID) and Water Sensitive Urban Design have as one of their tenets the use of rainwater harvesting (RWH) systems to provide water for use on site. Historically implemented in arid or semi-arid regions, RWH has recently surged in popularity in more humid regions, such as the southeastern USA, due to increased interest in water conservation during severe drought conditions. An LID commercial site in Raleigh, NC, incorporated RWH with other stormwater control measures to mitigate runoff quantity and improve runoff quality. A 57,900-liter RWH tank used for landscape irrigation was monitored to determine influent and effluent water quality. Samples were analyzed for total nitrogen, total phosphorus, total Kjeldahl nitrogen (TKN), total ammoniacal nitrogen (TAN), nitrite-nitrate (NOX), orthophosphate (Ortho-P) and total suspended solids (TSS). Low concentrations were observed for all pollutants monitored; for example, influent and effluent TP concentrations were 0.02 and 0.03 mg/L, respectively. Statistical testing showed significant increases in TAN and organic nitrogen (ON) concentrations by 33 and 38%, respectively, from inflow to outflow. NOX and TSS concentrations decreased significantly by 23 and 55%, respectively. Concentrations of all other pollutants were not significantly different between the inflow and outflow. Influent concentrations to the RWH tank were less than previously published rainfall pollutant concentrations, indicating potentially irreducible concentrations onsite. While a single case study, this RWH system appears to offer some pollutant mitigation, especially for TSS.


2014 ◽  
Vol 686 ◽  
pp. 132-141
Author(s):  
Yan Wu

With consideration of the special hydrogeological conditions and layout characteristics of the hydraulic structures, the seepage control measures of dam abutment and underground powerhouse on the right bank of JinPing-I hydropower station is drawn up. Based on the three dimensional finite element analysis of seepage control with dry area virtual flow constant mesh analysis method, the rationality of the seepage control measures of dam abutment and underground powerhouse has been verified and the key factors affecting the effect of seepage have been compared. In combination with the curtain of dam abutment, the curtain of underground powerhouse is reasonable. The results showed that the steel liner of penstock after the curtain is necessary.


2019 ◽  
Vol 45 (1) ◽  
pp. 333 ◽  
Author(s):  
A. Romero-Díaz ◽  
E. Díaz-Pereira ◽  
J. De Vente

Gully erosion causes severe damage to crops and infrastructures and affects the provision of ecosystem services worldwide. To assess the potential of gully control measures to protect ecosystem services and assess the conditions required for their large-scale implementation, this paper critically evaluates a range of gully control measures documented in the World Overview of Conservation Approaches and Technologies (WOCAT). Environmental and socio-economic impacts of technologies are assessed, as well as the implications for ecosystem services, costs and benefits of implementation, and stakeholder’s perception. It is demonstrated how gully control measures provide notable on-site and off-site benefits for socio-economic, cultural, ecological, and production goals, and to protect crucial ecosystem services. Control measures particularly contribute to soil and water conservation and to regulating ecosystem services by controlling soil erosion, water cycling, and natural hazards. Most effective control measures consist of combined vegetative and structural measures and of catchment wide interventions. While implementation of gully control can initially be expensive, on the long term, the cost-benefit ratio is usually positive. Moreover, the results emphasize the importance of evaluating control measures considering monetary aspects and all ecosystem services they provide. Nevertheless, individual farmers can often not afford the implementation and maintenance costs due to barriers for implementation and therefore require sustained institutional support. 


2014 ◽  
Vol 638-640 ◽  
pp. 766-769
Author(s):  
Wen Juan Cui ◽  
Li Qin Li ◽  
Wei Zhang

Calculation of seepage stability is important method in selection and justification of reinforcing dike seepage control measures. In the reinforcement design of the Qinhe river dike downstream, the finite element method of AutoBank is used to calculate the seepage stability of the dike reinforced before and after, and an economic and reasonable reinforcement scheme is selected then.


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