Search results for "Salinity"

Experimental analysis of a continuously operated reverse electrodialysis unit fed with wastewaters

2017

Reverse Electrodialysis (RED) is one of the most promising technologies to convert salinity gradient chemical energy into electricity. RED units are traditionally operated with natural streams as river water and seawater thereby limiting the spread of the technology in sites far from coastal areas. Aim of the present work is that of exploring and expanding feed possibilities for RED systems by employing waste streams. Thus, an experimental study was performed by testing, for the first time, a Reverse Electrodialysis (RED) unit fed with a high salinity wastewater originated in a fish canning factory, and a low salinity wastewater from a sewage treatment plant. Uninterrupted, long duration ex…

Reverse electrodialysis: advanced modelling and scale-up

Energetic Valorisation of Saltworks Bitterns via Reverse Electrodialysis: A Laboratory Experimental Campaign

2023

Concentrated bitterns discharged from saltworks have extremely high salinity, often up to 300 g/L, thus their direct disposal not only has a harmful effect on the environment, but also generates a depletion of a potential resource of renewable energy. Here, reverse electrodialysis (RED), an emerging electrochemical membrane process, is proposed to capture and convert the salinity gradient power (SGP) intrinsically conveyed by these bitterns also aiming at the reduction of concentrated salty water disposal. A laboratory-scale RED unit has been adopted to study the SGP potential of such brines, testing ion exchange membranes from different suppliers and under different operating conditions. M…

Hydrologic and geochemical survey of the lake ‘‘Specchio di Venere’’ (Pantelleria island, Southern Italy)

2007

Hydrological and geochemical studies performed on Lake Specchio di Venere on Pantelleria island (Italy) indicate that this endorheic basin has been formed through upwelling of the water table, and that it is continuously fed by the thermal springs situated on its shores. The lake is periodically stratified both thermally and in salinity, albeit this stratification is rather unstable over time, since meteorological events such as strong rain or wind can determine the mixing of its waters. Periodical analyses of the lake water chemistry show large variations of the salt content due to the yearly evaporation-rain dilution cycle. These processes are also responsible for the saline stratificatio…

Field and laboratory approaches for determining sodicity effects on saturated soil hydraulic conductivity

2006

Abstract Dilution of high-sodicity soil water by low-sodicity rainfall or irrigation water can cause declining soil hydraulic conductivity (K) by inducing swelling, aggregate slaking and clay particle dispersion. Investigations of sodicity-induced reduction in K are generally restricted to repacked laboratory cores of air-dried and sieved soil that are saturated and equilibrated with sodic solution before tests are conducted. This approach may not yield a complete picture of sodicity effects in the field, however, because of loss of antecedent soil structure, small sample size, detachment of the sample from the soil profile, reliance on chemical equilibrium, and differing time scales betwee…

Environmental, Agricultural, and Socioeconomic Impacts of Salinization to Family-Based Irrigated Agriculture in the Brazilian Semiarid Region

2020

Soil salinity is one of the major abiotic factors causing a serious threat to global food security, mainly in arid and semiarid regions. Salinity brings socioeconomic impacts associated with low crop productivity and devaluation of agricultural lands. In this chapter, we approach agricultural, environmental, and socioeconomic impacts of soil salinization. We also report two case studies from irrigated areas of the Brazilian semiarid, where previously cultivated lands were abandoned due to increased soil salinity. A survey of the published literature showed that soil salinity became a global problem that is accelerated by human activities such as deforestation and lack of irrigation manageme…

Spatial microbial community structure and biodiversity analysis in "extreme" hypersaline soils of a semiarid Mediterranean area

2015

In recent years specific attention has been paid on the biotechnological potential of microorganisms in extreme soils, in particular in saline soils. Salinity is one of the most widespread soil degradation processes on the Earth, and saline soils can be defined as extreme soils or border line habitats in which several factors, as high salt content, may limit the growth of organisms. In this study, the physical, chemical and microbiological soil properties were investigated in the shallower horizon of natural saltaffected soils in Sicily (Italy). The main aim of the research was to evaluate the structure and diversity of bacterial and archaeal communities by terminal-restriction fragment len…

Salinity-induced responses and resistance in Trifolium repens L.

2015

Abstract White clover ( Trifolium repens L.) is a commonly cultivated legume with good ground cover potential often used with companion grass species in urban grassed areas. The effect of increased soil salinity on plant growth is an urgent problem in cities where NaCl is used as a de-icing material. The aim of this research was to examine the effect of different salinity levels and K supply-induced responses and tolerance in the T. repens L. variety ‘Daile’, a variety which is used in urban greenery. To analyze the impact of increased soil salinity and the antagonistic effect of K, the effect of gradually increasing NaCl (0, 20, 40, 60, 80, 100 mM) and K (+0, +100, +200, +300 mg/L) levels …

Agriculture and grazing environments

2019

Abstract The increase in world population increases the pressure on soil resources and triggers land degradation. Agricultural and grazing environments are one of the most vulnerable ecosystems to this process. Degradation affects importantly soil fertility. Millions of hectares are affected and soil productivity is endangered. This decreases soil ability to provide ecosystem services in quantity and quality. Managers and decision-makers should be open to adopt environmentally-friendly practices and contribute to land degradation neutrality. This chapter focuses on the problems induced by some of the most common soil degradation processes caused by in agriculture and grazing activities. Rev…

Assessment of soil suitability for improvement of soil factors and agricultural management

2019

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