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Estimates of sediment and nutrient yields in conjunction with erosion modelling are essential to issues of land and water management, including sediment transport and storage in lowland reservoirs, estuaries, irrigation and hydropower systems. The purpose of this project was to investigate and show the feasibility of using GIS techniques in the analysis of sediment and nutrient yields. In this case study the emphasis was on the spatio-temporal distribution of sediments and nutrient yields. GIS overlay techniques were used to compute various maps showing spatial distribution of nutrients and sediments with time. GIS interpolation enabled estimation of yields in areas without measurements. Lastly, an erosion hazard analysis using the SLEMSA model was undertaken in a GIS environment to produce an erosion hazard potential map. GIS proved to be a powerful, efficient and capable tool especially in the analysis of sediment and nutrient yields for an agro- rural watersheds which sometimes are remote and inaccessible. The powerful GIS interpolation techniques provided a way to overcome data gathering challenges in such areas.
The ArcView–Soil and Water Assessment Tool was used to evaluate the potential environmental benefits the Conservation Reserve Program (CRP) in the Beaver River watershed, Texas County, Oklahoma. The SWAT model was used to simulate erosion rates and related stream water quality. Calibration results using monthly predicted values generally matched well with the observed values of two USGS gage stations in the watershed. The simulated sediment yield was inversely proportional to the CRP areas, with an overall 30% reduction in annual sediment yield. Sediment yield was highest from wheat, general agriculture and corn fields. Mapping sediment yield determined priority areas for future CRP enrollment. Correlation analysis revealed a good inverse relationship between sediment yield and areas under CRP. Wheat fields accounted for about 71% of total phosphorus and 77% of total nitrogen lost in Texas County. Results from Patch Analyst showed an increase in grassland area, a decrease in number of patches, and an increase in average patch size. Analysis of changes in landscape structure indicated that CRP can potentially improve the quality and quantity of wildlife habitat.
Soil erosion is causing degradation and loss of the critical natural resources necessary for the sustenance of human life on the planet. It is a serious problem in arid and semi-arid zones like Pakistan due to sparse vegetation and high rain intensities mainly concentrated in monsoons seasons. Pakistan has many potential sites for hydropower projects, but sediment discharge data is not available at many locations for the estimation of reservoir life etc. Present study is designed to focuses on soil erosion and sediment yield estimation using USLE and GIS at small watershed scale. Results of the model can be used to predict the sediment inflow to the reservoirs. Model shows that USLE underestimated sediment yield by 40 to 60% as compared to the observed sediment yield. The obvious reason is that USLE is an empirical equation and does not consider the transfer of mass and energy within the watershed, however for watershed scale modelling this accuracy is enough to explain the soil erosion and sediment yield characteristic of the watershed.
A good knowledge of possible changes of nutrient stock of a system involves balancing of nutrient input and output in the system (nutrient flow analysis). Nutrient flow analysis using an approach based on “balance” is one of the possible ways to estimate the diversities in the sources and flows of nutrient content of a system (applied fertilizer, fertility in soil, plant mineral uptake and crop residue). It quantifies the whole system management method together with their cost and time. However, nutrient balances involving flows of few nutrient elements are considered “partial balances” because they basically show only a portion of what the farmer takes out of the system and what they put back.
Sedimentation is a significant natural phenomenon affecting hydro power reservoirs. Apart from major watershed problems such as loss of soil fertility and productivity caused by soil erosion, increased sediment load associated with erosion processes reduces the storage capacity and shortens the useful life of reservoirs. In view of this, an investigation of the hydrological processes and sediment transport mechanism at the upstream catchments of hydro power reservoirs is critical to the sustainable operations of hydro power dams. This book therefore provides a detailed sediment management modelling procedure using the Soil and Water Assessment Tool (SWAT) interfaced with Mapwindow-GIS to simulate the hydrology, predict the sediment yield and identify erosion prone areas of a watershed upstream of Jebba Reservoir in Nigeria. Four sediment management scenarios were considered while cost implications of different management scenarios were also examined. This book can be useful to professionals in Water Resources Engineering, Lecturers,graduate and postgraduate students and other individuals interested in the area of sustainable management of water and sediments in a watershed
Poor land use practices and improper management systems have played a significant role in causing high soil erosion rates, sediment transport and loss of agricultural nutrients. In this research a physically based watershed model, AVSWATX is applied to the Upper Ribb River watershed for modelling of the hydrology and sediment yield to predict the sediment yield to Ribb dam reservoir. The model is calibrated and validated taking the Upper Ribb gauging station near Debretabor. 20 years daily meteorological, flow and sediment rating curve equation for sediment data BCEOM (1999) are used for model calibration and validation. The model is calibrated and validated for both flow and sediment concentration at upper Ribb (844km2) and run at Ribb dam reservoir outlet (686km2) to estimate the sediment yield. The result indicated that the observed values show good agreement with simulated value for both flow and sediment yield. In this study the SWAT model yields average annual sediment of 72.79 ton/km2 (7279 ton/ha) at Ribb dam site. The result of the study could help different stakeholders to plan and implement appropriate soil and water conservation strategies.
Some aspects relating to growth and performance of agro-based industries like socio-economic characteristics, capital structure, employment and level of output are covered and suggestions emanating from the conclusions are offered for ensuring a better performance in selected agro-based industries in Andhra Pradesh, India. In the present study the impact on rural employment, rural income and wage structure, analyze the contribution on socio-economic development and effort made by the Government to develop rural infrastructure, agro-based industries for the uplift of the rural economy and study on infrastructural facilities of agro-based industries in rural areas at micro level in Andhra Pradesh, India
Water is elixir of life, without it life is not possible. Watershed based study is required for management of sustained use of water and other ecosystem resources. A geomorphic analysis of river basin is essential to solve water scarcity of the arid and semi-arid region through watershed management. This book contains geomorphological approach for sustainable watershed management of the semi arid Yerla watershed, Deccan Trap region, India using geospatial techniques. Author has analysed geomorphological, hydrological and land use - land cover characteristics of study area and presented a model of watershed structures according to geomophology of hilly, plateau and lower reaches micro watersheds. Present work is useful to solve basic water requirement of the region. The book is an essential to all students and researchers of geography, geology and environmental sciences with special interest in tropical world.
Soil fertility management continually requires incorporation of organic matter, including organic carbon, into soils which is achievable through litter decomposition followed by constant release of nutrients contained in the plant biomass. Nutrient enrichment of the soil creates a healthy environment for the soil fauna and flora to thrive to the amelioration of soil fertility status vital for the sustainable productiveness of food production systems. Soil fertility is a function of the soil organisms, the micro-, meso- and macro-fauna and flora inhabiting the soil ecosystem. Life processes going on in the soil ecosystem facilitate nutrient uptake by the plants, thus enhancing the productivity of the producers and improving the overall functioning of an agro-ecosystem to be pronounced in sustainably high yields of foods necessary for human wellbeing. This volume discusses decomposition and dynamics of nutrient release in agroforestry systems in the Tarai area of Central Himalayas. Agroforestry systems are ecologically more stable than the croplands without trees. The book would be highly useful for all those concerned with the state of agro-ecosystems and sustainable agriculture.
The study has aimed at working with the level of income of rural households from different sources and employment of rural household in different topographical strata. An effort has been made in this study to furnish occupation pattern of the members of the rural households. The study has also aimed at measuring extent of poverty of rural households. An analysis has been carried out to explore whether a change in different topography is made, the level of income and employment of rural household pattern is also changed.
Sedimentation from agricultural fields and seasonal euthrophication from non-point source nutrients are the main problems in the Lake Tana, upper Blue Nile Basin (BNB) of Ethiopia. The main objective of this study was to show the role of wetlands on sediment absorption. Two wetlands were selected purposefully to quantify how much sediment and nutrient trapped by the wetlands. All sampled runoff were filtered and measured to determine sediment amount in gram per liter. Only 10 representative samples were subjected to nutrient analysis. Landsat images of 1985 TM, 1995 TM, 2000 ETM+ and 2011 ETM+ were used and supervised classification was applied to know changes of wetlands. In general, about to 86 % of the incoming sediment was absorbed in site 2, whereas 80 % in site 1. Regarding the nutrient loss, 53 and 33 % nitrogen and 50 and 29 % phosphorus absorbed by the wetlands from incoming load in site 2 and site 1, respectively. About 49 % of OM was absorbed by the wetland in site 2, whereas, it was 31 % in site 1. In the three periods, 1985-2011, wetland change was obtained. Nearly 119 square km (27 %) of the wetland was converted to the other land use types in the last 26 years.
The maize crop in many underdeveloped countries, particularly in Africa, plays an important role as main source of food and food security, the maize production is constrained for nutrient deficiency. Nutrient depletion and Soil degradation are major problems leading to low soil fertility productivity, hunger, and poverty. Nitrogen is the most deficient nutrient in nearly all soils and Phosphorus is the second limiting nutrient. Thus there is need to identify an affordable management strategy for sustainable maize production which conserves nutrients in the soil, increases yields of maize or other crops and improves soil properties with minimum use inorganic fertilizer. The aim of this work is to search for solutions to the high cost of crop production by partial use of organic sources of nitrogen in conjunction with small doses of inorganic fertilizer.
Mono cropping is a dominant practice in Ethiopia, and leads to crop failure, depletion of soil nutrient, develop disease and pests, and reduce farmers income, but farmers of the country commonly use intercropping to overcome yield reduction, diversify nutrient source, improving soil fertility, and increase land use efficiency. Statistical analysis showed that intercropping of faba bean and wheat to increase biomass and seed yields, land use efficiency, monetary value, soil fertility, and minimizing of risks associated with mono cropping.
This study was undertaken to focus on the integrated watershed management and its impact on the long term environmental change, agriculture development and also the development of the socio-economic condition of the rural Barind area. For this, by establishing a large number of Deep tube-wells and Shallow tube-wells for pumping out ground water, the Barind Multipurpose Development Authority (BMDA)has build up an artificial watershed network for irrigation over the projected area. This study nevertheless, has revealed some basic and interesting aspects of rural growth and it is hoped that it will creat curiosity and encouragement for other researchers to undertake further studies of this and other areas of the country which, besids its academic interest,is of great significance for national development.
The prime purpose of this book is to present the detail morphometric characteristics of a watershed based on digital terrain model and GIS. A short glance is presented on the geology and geomorphology of Karawan watershed of Yamuna basin, India. The basic concept of Indian watershed codification system is also presented in the book. Extensive morphometric parameters i.e. drainage network (16), basin geometry (28), drainage texture analysis (7), and relief characterizes (34) are carried out based on digital analysis. The parameters are discussed in detail and values are obtained using ASTER (DEM) data and ArcGIS-10 software. The book is useful for the instructors, research scholars and students of geomorphology for a deeper study in the field of drainage basin analysis.