Salinization Of Water Resources Research Articles

FUTURE FLOODING OF THE VOLTA DELTA CAUSED BY SEA LEVEL RISE AND LAND SUBSIDENCE

The Volta delta(Ghana, West Africa) is increasingly impacted by sea level rise (SLR). SLR makes the Volta delta mostly vulnerable to flooding, salinization of water resources and agriculture fields, and permanent loss of lands. This would potentially threaten and present a growing risk to its population, infrastructure and economy, and even worsen due to land subsidence (LS). Relative sea level rise (RSLR) in this study is the rate of LS with respect to SLR. It is thus very important to precisely quantify LS rates together with SLR as well as planning and assessment of countermeasures. This study is in two parts, The first study presents and discusses recent LS rates in the Volta delta derived from satellite-based SAR-Interferometry and their impact on relative SLR. The second study, also assesses major hydrodynamic parameters (Wave runup, Sea Level Anomaly,tide and atmospheric conditions) that play a role in extreme coastal flooding events.

Special Issue “Salinization of Water Resources: Ongoing and Future Trends”

All over the Earth, more and more studies have shown the effects of climate changes generated by anthropic release of greenhouse gasses on the hydrological cycle [...]

Studies on water resources salinization along the Italian coast: 30 years of work

The population density on the Italian coasts is twice the national average. Numerous urban, economic, and productive settlements lie along the coast, which in many areas have altered the natural characteristics of the territory. Moreover, recent climate change studies forecast large impacts on the hydrologic cycle in the Mediterranean. Thus, in the next years, coastal water resources will be gradually more stressed. This in turn may result in a progressive salinization, which is a widespread and worrying phenomenon worldwide. In this paper, the historical and geographical distribution of peer-review studies focusing on the salinization of water resources along the Italian coasts will be critically discussed.

Evaluation of salinity tolerance of three olive (Olea europaea L.) cultivars

Tarom region of Zanjan province is one of the olive production centers in Iran, which faced a crisis of salinity stress following the salinization of water resources. The selection of salinity tolerant cultivars using pivotal characteristics is one of the interesting challenges. This study was conducted to investigate the behavior of ‘Zard’, ‘Abou-satl’, and ‘Arbequina’ cultivars in the context of using marginal waters. Therefore, one-year-old self-rooted plants of these cultivars were potted and irrigated with 2, 5, 8, and 12 dS/m saline water for three months in the greenhouse, and certain physiological and morphological features were studied. The results show that ‘Zard’ and ‘Abou-Satl’ cultivars tolerated salinity of 8 and 12 dS/m, maintained their photosynthesis in medium salinity (5 dS/m), and grew well in these conditions. In contrast, the ‘Arbequina’ cultivar exhibited extreme susceptibility to salinity. In the high salinities, there was a lower slope in the increase of Na+ concentration in the leaves of the ‘Zard’ cultivar. Also wet and dry biomass in this cultivar decreased much less than the others. A more severe reduction in the transpiration of the ‘Zard’ cultivar indicated better efficiency of water retention mechanisms and high water use efficiency. The photosynthesis rate of ‘Zard’ and ‘Abou-Satl’ cultivars were less affected under salinity stress. They reduced the accumulation of Na+ and increased the K+ concentration in leaves. These two cultivars had suitable responses to salinity and were recommended for planting in regions affected by salinity.

Perceptions of the problems of drinking water supply in Ziguinchor (Senegal): Case of the peripheral district Nema 2

Good water quality is important for the human health, energy and development. However, it is not available to millions of people throughout the world. In the Casamance region, the climatic situation has been characterised for the last thirty years by a drop in rainfall, combined with a demographic explosion which has led to an intensive exploitation of available water resources. Ziguinchor, the main city of Casamance, although located in a humid region rich in rainwater, does not guarantee continuous access to drinking water for all its inhabitants, especially those living in the outlying districts. The aim of this article is to show that the difficulties of access to drinking water in the outskirts of Ziguinchor are closely related to the inadequacy of the infrastructure for water supply. The methodology adopted revolves around three main axes: documentary research, data collection and data processing. The results of this study reveal that the water production capacity in Ziguinchor, of 9,500 m3 per day (i.e. 400 m3/h), in fact presents a production deficit in relation to demand from population estimated at 583,528 inhabitants, mainly noted in the peripheral zone such as N?ma 2. The causes of this mismatch between supply and demand are due to inadequate infrastructure, but also to the pollution and salinity of water resources, in addition to poor governance of the supply sector. Faced with this situation, there is an imperative to mobilise water resources in the commune in a properly rational manner and to ensure more sustainable management.

Relationship between Senonian and deep aquifers in Southern Tunisia

Steady increase in the salinity of water resources and the decline in the groundwater level are the most widespread processes that degrade water-quality and endanger future water exploitation in Southern Tunisia. Hydrological, geochemical and environmental isotope data were evaluated to characterize the recharge conditions of the Senonian aquifer and the flow pattern of groundwater mixing. The results show that groundwaters can be classified into two major water facies: Ca–SO4–to mixed and Na–Cl. The main hydrogeochemical processes that typically control the groundwater mineralization are dissolution of evaporites (halite, gypsum and anhydrite), evaporation, cation exchange and mixing process related to the up-flow leakage of deep groundwaters. The stable isotope signatures reveal that the main part of groundwater is significantly affected by evaporation process. Wide range (−4.5 to −8.4‰) and spatial heterogeneity of δ18O in groundwater indicate that the aquifer is characterized by a slow process of natural groundwater in its lateral extent. The 14C activity varies between 43 and 0.33 pmc. The 13C contents of the total dissolved inorganic C (TDIC) range between −10.8 and −3.6‰. The calculated 13C contents of the CO2 in equilibrium with the TDIC, varying between −15.1‰ to −11.4‰ indicate two origins of C in solution: the carbonate matrix (δ13C = −2‰) and the soil CO2 (δ13C from −26‰ and −22‰ for the cultivated areas). Mean residence times have been determined after correction of the initial activities for dead C from the rock matrix. The mean residence times confirm a modern recharge of the groundwater from Dahar upland and indicate the presence of palaeowaters in the northern and southern parts of the basin. Detailed investigations on identifying the potential recharge zones, flow-paths of mixing and recharge conditions will be useful to protect the groundwater resources from depletion and salinization.

Whither Australia: Will Availability of Water Constrain the Growth of Australia's Population?

AbstractSupply of water for cities and for food production will not be a major factor limiting the growth of Australia's population in coming decades. The water needed to sustain the population of Australia can be divided into two kinds. Direct water requirements are those that meet the immediate needs of the people – potable water supply and waste removal. Indirect water requirements refer to the water needed to sustain the economy and the standard of living – food production, manufacturing, mining, etc. Agriculture is the largest indirect user, using between 50% and 70%, while household use, including sewerage and drainage, uses less than 30%. Industry uses the remaining 20%. In this paper, we do not deal with the issue of water quality but note its significance, especially as regards the salinisation of water resources in rural Australia. Australia has abundant water when expressed on a per capita basis, although this is unevenly distributed around the continent. Per capita, the densely populated south‐eastern and south‐western parts of the continent have low to average run‐off available when compared with other populated regions of the world. What is more important is the extreme inter‐annual variability of that run‐off. Previous attempts to measure the size of the population that could be supported in Australia, based on the availability of water, have produced estimates up to 280 million. Outside of the well‐watered edges of the continent, water has always been seen as a factor that limits Australia's population. However, water supply is a necessary but not sufficient basis for population growth, as can be seen from examples (such as the Ord Irrigation Scheme) where providing abundant water has failed to trigger major population growth. The largest increases in population in coming decades are predicted to occur in the capital cities where there has been a substantial reduction in water use through demand management in recent years. Urban water demand has proven to be extremely elastic. New sources of urban water, including desalination, groundwater, recycled sewage, and increased run‐off in urban stormwater, will easily provide sufficient water for a growing urban population over coming decades. Water used in irrigated agriculture at present supplies the needs of Australia's 20 million people and an estimated 40 million in other countries. With increased efficiency in the delivery and use of water for irrigation combined with export substitution, water for food production is not likely to limit population. In this paper, we have not dealt with the issue of environmental flows in rivers or with the provision of water to wetlands, although we acknowledge that they are both significant issues for policy development. We conclude that the size of the population of Australia is less important than how that population behaves in regard to the management of water resources.

An overview of water logging and salinity in southwestern Australia as related to the ‘Ucarro’ experimental catchment

Water logging and salinity are major forms of land degradation in southwestern Australia and are predicted to become even more extensive. There are basic requirements for the development of salinisation and water logging within the specific geology and geomorphology of the region. The nature, extent and consequences of water logging and secondary salinity in the agricultural areas of southern Australia is presented in overview with a particular emphasis on the type of landscape represented by the ‘Ucarro’ experimental site, near Katanning in southwestern Australia. Three types of water logging are identified. These are associated with perched aquifers in texture-contrast (duplex) soils, inundation of terraces and valleys, and saturation in surface soil due to the hydraulic pressure being above ground level in aquifers at the base of the regolith of highly weathered granites and gneisses or within channels in broad valley sediments. A dominance of the vertical component of flow in perched aquifers is identified which contributes significantly to recharge of deep aquifers and subsequent land salinisation. Water logging has reduced the potential yield by 30–80% for many crops and pastures in the >400 mm rainfall zone. Increasing land salinisation has been accompanied by increasing trends in salinity of water resources. There is an interaction between water logging and salinity where groundwater discharge occurs at the soil-surface. Water logging may be the more serious inhibitor for plant growth than salt even at low salt levels. The interaction of water and salt is synergetic for plants. Remotely-sensed techniques using surrogates such as vegetation type and condition have been developed to provide broad spatial assessments of saline and water-logged areas since 1987. In 1990, the shires to the east and west of ‘Ucarro’ had 9.1 and 2.4% of agricultural land salt-affected, respectively. In both shires, a 0.7% increase in salt-affected land has occurred in the last 8 years.