We analyzed the impacts of deforestation on water quantity and quality in the Tapajós River, one of the main tributaries of the Amazon River. To that end, we used data from 2 years of fieldwork as well other state-of-the-art techniques in small and large areas of this study area. We found changes in water quality and quantity across small and large portions of this area. Our results show that some impacts of deforestation usually observed in small streams are also affecting the major river. Hide

By using the RUSLE model and GIS, changes of sediment yield and sediment transport were assessed in Zhifanggou watershed. The obtained results were basically consistent with the measured values. From 2000 to 2010, the amount of soil erosion was reduced yearly. The soil erosion intensity of terraced fields, sloping land and construction land were mainly very low due to soil and water conservation measures. And soil erosion increases with increasing slope in the range of 0–15 °. Hide

The paper investigates the use of GIS to come up with model parameters. This is part of a process of simplifying model use. The findings show that existing GIS data can be used for estimating model parameters as the outcomes of the research show that model outputs are consistent with previously estimated measures. This research is part of a development of a model which can estimate soil loss and sediment delivery at broad spatial and temporal scales to improve catchment management. Hide

WQSAM is a water quality model designed specifically for South Africa as it relies on flow data generated by South African-specific flow models. However, many of the characteristics of WQSAM would make it suitable for other developing semi-arid countries. This study attempted to adapt WQSAM to take in flow data from the globally-applied WEAP flow model so that WQSAM can be applied elsewhere. WQSAM could effectively use the flow data from the WEAP model as demonstrated on a case-study catchment. Hide

The control of sedimentation in a reservoir provides a global evaluation of the process of erosion and transportation of sediment. Knowledge of sedimentation is useful for reservoir management. Bathymetric surveys can be used to assess the silting volume of dams. The results of two surveys of the Ghézala dam reservoir in northern Tunisia are available. The measurements provide initial information about the quantity and variability of silting and the mechanism of sediment deposition. Hide

Enhancing knowledge of the role of morphological changes (volume) with this new methodology is an opportunity to gain better understanding of river bed sediment transport. This type of study will support dredging projects in the Orinoco River to maintain navigability, which will contribute to the management of this important river basin. Hide

We present 2D morphodynamic simulations of hydraulics and sediment deposition patterns over an exposed bedrock anastomosed pavement. Alluvial barforms appear to be initiated through sediment deposition in bedrock topographic lows. It is likely that vegetation establishment in these depositional loci increases the cohesive strength of the deposited sediment and captures additional sediment and propagules, eventually leading to greatest thicknesses of alluvium positioned over the bedrock lows. Hide

Soil erosion result in the deposition of sediments into rivers and reservoirs. The sediments affect the water quality resulting in the treatment of the water being expensive. The sediments that are carried into the reservoir reduces the capacity of the dam. The reduction of water quality in Chimhanda dam as well as the increase in the cost of treatment of the water pushed the author to do a research. Hide

This study was designed to prove that the coastal changes of the Gulf of Tunis are mainly driven by the changes of the hydrological regime of the Medjerda river due to dams. We sampled cores of sediments in the low valley just before the sea, and analyzed them. They show the dramatic reduction of sediment supply after 1981, date of construction of the largest dam of Sidi Salem, and the disappearance of sand in the fluvial sediments. Hide

The aim of this study consists in testing the effectiveness of satellite data in order to monitoring shoreline and sedimentary features changes, especially the rapidly changing of Gulf of Tunis coast. The study area is located in the Gulf of Tunis western bay (Southern Mediterranean Sea) which is characterized by sandy beaches of Ghar Melah and Raoued (Medjerda Delta area). The aerial photographs and satellite imageries were 15 used for mapping the evolution of shoreline. Diachronic data. Hide

This study describes a model for incorporating regional variability in water supply costs into an energy planning model and the impacts of this on the most sustainable future energy mix for a country as well as the potential impact that energy related policies can have on the future of water supply availability in different regions. Modeling of the water-energy nexus is particularly relevant as water supply becomes more variable due to climate change and a potential constraint on development. Hide

We draw on previous work examining likely future water use and food availability in Pakistan and extend the analysis to consider hydropower generation and energy demand in food production. The biophysical limits of the water-energy-food nexus are just one piece of the picture. We also draw on critical social science and resilience or adaptation-oriented perspectives to consider options usually deemed out of scope for biophysical scientists or water, energy and agricultural authorities. Hide

To meet the global goals (SDGs) on energy and climate, local communities must move towards sustainable energy systems. Our study explores the indirect water uses linked to the supply of energy in 21 counties of Sweden – the country considered to be most advanced towards meeting the SDGs. Results show that the quantity and geography of energy-related water use vary greatly between counties. Further, local inventories of CO₂-emissions or direct water use poorly correlate with these variation. Hide

The study used a combination of methods to investigate the feedback mechanisms of the food-water-energy nexus of the Shiroro hydropower station and its environs. The study shows that while there is a general decline in rainfall, coupled with low level of reservoir reliability, the area of agricultural landsue around the dam has increased significantly. In view of these realities, the study recommends that a roadmap to improve the operational coordination and management of the dam be put in place. Hide

Water and food security are vital for improving livelihoods in disadvantaged rural areas. Understanding the water cycle is central to the design of watershed development works intended to improve water security. Better farming practices can help improve food security. It is also vital for social constraints and equity to be considered. Finally, a participatory learning approach is useful for ensuring that watershed development work is effective in producing long-term improvement in livelihoods. Hide

A statistical model has been developed for forecasting domestic water demand in Haihe river basin of China due to population growth, technological advances and climate change. Historical records of domestic water use, climate, population and urbanization are used for the development of model. An ensemble of seven general circulation models (GCMs) namely, BCC-CSM1-1, BNU-ESM, CNRM-CM5, GISS-E2-R, MIROC-ESM, PI-ESM-LR, MRI-CGCM3 were used for the projection of climate and the changes in water demand. Hide

A part of the population of Mexico is undergoing severe water crises vis-a-vis with the quantity and quality of water. The water authority's strategy dwells solely in infrastructure development to tackle the symptoms, not the causes. The paper summarizes how the causes of crises lie not in the lack of infrastructure but in a deficient management and governance. I did the research because I'd to influence on policy, and I did it through fieldwork and critical literature review. Hide

As a result of global climate change nowadays Ukraine is facing the problem of environmental degradation of river basins. Thus, achieving an acceptable level of water security in Ukraine should be defined as the strategic objective of national water policy. The basic principles of a new water policy are supposed to be represented in Water Strategy of Ukraine. Integrated water management by the basin principle should serve as a main tool for achieving the objectives of country's water security. Hide

It is shown that in agriculture technologies soil mulching with plant remains leads to increase in the ratio of actual transpiration to potential one and to increase in the yield of crops. Soil mulching with plant remains in combination with subsurface cultivation is the most efficient agricultural mode for the regions of the steppe and forest-steppe zones of the East-European (Russian) plain. This technology is most promising for development of agriculture in these regions. Hide

Phosphorus is necessary for the development of crops and is therefore essential in safeguarding our food security. Several studies predict that our rock phosphate reserves, used to create synthetic, phosphatic fertilizers, may become depleted within this century. This study roughly approximates for which areas in Africa we can instead recover phosphorus from wastewater in order to reduce our dependancy on unsustainable rock phosphate. Hide

Soil erosion susceptibility analysis was based on rainfall, Land use, slope and soil erodibility factor. GIS was used to produce the basin susceptibility to soil erosion using weight index of each factors. The results revealed that 106.66 km² (25.70 %) and 164.80 km² (39.7 %) of the basin have high and very high susceptibility to soil erosion. The over 50 % high susceptibility of catchment area has negative implications on ecosystem services of the s stream. Hide