Articoli di riviste: "Salinisation"

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De Pascale, Stefania, Francesco Orsini, Rosanna Caputo, Maria Antonella Palermo, Giancarlo Barbieri e Albino Maggio. "Seasonal and multiannual effects of salinisation on tomato yield and fruit quality". Functional Plant Biology 39, n. 8 (2012): 689. http://dx.doi.org/10.1071/fp12152.

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The effects of short- and long-term salinisation were studied by comparing tomato growth on a soil exposed to one-season salinisation (short term) vs growth on a soil exposed to >20 years salinisation (long term). Remarkable differences were associated to substantial modifications of the soil physical-chemical characteristics in the root zone, including deteriorated structure, reduced infiltration properties and increased pH. Fresh yield, fruit number and fruit weight were similarly affected by short- and long-term salinisation. In contrast, the marketable yield was significantly lower in the long-term salinised soil – a response that was also associated to nutritional imbalance (mainly referred to P and K). As reported for plants growing under oxygen deprivation stress, the antioxidant capacity of the water soluble fraction of salinised tomato fruits was enhanced by short-term salinisation, also. Overall, long-term salinisation may cause physiological imbalances and yield reductions that cannot be solely attributed to hyperosmotic stress and ionic toxicity. Therefore, the ability of plants to cope with nutritional deficiency and withstand high pH and anoxia may be important traits that should be considered to improve plant tolerance to long-term salinised soils.

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Schulz, Claus-Jürgen. "Salinisation of running waters". Limnologica 41, n. 2 (maggio 2011): 79. http://dx.doi.org/10.1016/j.limno.2011.01.003.

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Hoey, D., M. Ahmed e M. Littleboy. "Landscape Salinisation and Management: An Australian Perspective". Journal of Agricultural and Marine Sciences [JAMS] 7, n. 2 (1 giugno 2002): 53. http://dx.doi.org/10.24200/jams.vol7iss2pp53-60.

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Australian landscapes are facing an increasing salinisation threat. It is estimated that 2.5 million hectares are affected by land salinisation, and this area is expected to triple by 2050. Federal and State governments have jointly developed a policy framework to address this issue, with each state refining their own salinity management strategies within this framework. Scientific assessment and modelling underpin these salinity management strategies, though socio-economic considerations are also important. Landscape salinity assessment techniques used in the Australian context are outlined, and examples of salinity hazard and recharge mapping at the landscape scale described. Current developments in both recharge assessment, and groundwater flow modelling in Australia are described, and the use of these models in underpinning state salinity strategic planning discussed. The salinity management ‘toolkit’ is discussed. The progression from initially applying engineering solutions to deal with the symptoms of salinisation; to dealing with the causes of salinisation; to developing an integrated catchment management approach; to including a stronger emphasis on market-based economic measures; and the importance of over-arching Catchment Blueprints, is described in detail.The application of knowledge and experience gained through the management of Australian land salinisation to other countries is discussed in the context of the salinity problem in the Sultanate of Oman.

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Chabab, Elena, Michael Kühn e Thomas Kempka. "Upwelling mechanisms of deep saline waters via Quaternary erosion windows considering varying hydrogeological boundary conditions". Advances in Geosciences 58 (14 novembre 2022): 47–54. http://dx.doi.org/10.5194/adgeo-58-47-2022.

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Abstract. Intrusion of deep saline waters into freshwater aquifers does not only endanger the regional drinking water supply, but also rivers and stagnant waters and their fauna are threatened by salinisation. The upwelling of highly mineralised saline waters in large parts of the North German Basin is favoured by the presence of Elsterian glacial erosion windows in the Lower Oligocene Rupelian Clay, the most important hydraulic confining unit in this region. Lower precipitation rates and decreasing groundwater levels as a consequence of global climate change, but also anthropogenic interventions, such as increasing extraction rates or the use of the deep geologic subsurface as a reservoir, decrease the pressure potential in the freshwater column and may possibly accelerate this primarily geogenic salinisation process in the coming years. Density-driven flow and transport modelling was performed in the scope of the present study to investigate the upwelling mechanisms of deep saline waters across Quaternary window sediments in the Rupelian. Simulation results show that the interactions between the groundwater recharge rate and anthropogenic interventions such as extraction rates of drinking water wells or the utilisation of the deep subsurface, have a significant influence on the groundwater pressure potential in the freshwater aquifer and associated saltwater upwelling. In all scenarios, salinisation is most severe in the sediments of the erosion windows. Hydraulically conductive faults also intensify salinisation if located nearside erosion windows or induce a more distributed or localised salinisation in aquifers with drinking water relevance in areas that do not intersect with erosion windows. A decline in groundwater recharge thereby significantly favours upward saltwater migration. The simulation scenarios further show that a decrease in groundwater recharge also results in freshwater salinisation occurring up to 10 years earlier, which underlines the need for waterworks to initiate effective countermeasures quickly and in time.

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Pauw, P., P. G. B. de Louw e G. H. P. Oude Essink. "Groundwater salinisation in the Wadden Sea area of the Netherlands: quantifying the effects of climate change, sea-level rise and anthropogenic interferences". Netherlands Journal of Geosciences - Geologie en Mijnbouw 91, n. 3 (novembre 2012): 373–83. http://dx.doi.org/10.1017/s0016774600000500.

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AbstractHydrogeological research in coastal areas has gained considerable attention over the last decades due to increasing stresses on fresh groundwater resources. Fundamental groundwater flow and solute transport analyses remain essential for a concise understanding of the governing processes that lead to salinisation of fresh groundwater resources. However, the challenge of modern research is the application and quantification of these processes in real world cases. In this context, deltaic areas are amongst the most difficult study areas as they often have a complex groundwater salinity distribution. The Wadden Sea area in the northern part of the Netherlands is an example of such an area.We quantified salt water intrusion and salinisation of groundwater flow systems in two representative case studies in the Wadden Sea area, using the density dependent groundwater flow and transport code M0CDENS3D. The results indicate that sea-level rise and autonomous processes will cause severe salinisation in the future, especially in the low polder areas close to the sea. In addition, we show that enhanced land subsidence due to salt exploitation accelerates this process. Salinisation can be mitigated to some extent by raising surface water levels in polders and by creating saline groundwater collection areas that maintain a low controlled water level.

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Tillner, Elena, Maria Langer, Thomas Kempka e Michael Kühn. "Fault damage zone volume and initial salinity distribution determine intensity of shallow aquifer salinisation in subsurface storage". Hydrology and Earth System Sciences 20, n. 3 (8 marzo 2016): 1049–67. http://dx.doi.org/10.5194/hess-20-1049-2016.

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Abstract. Injection of fluids into deep saline aquifers causes a pore pressure increase in the storage formation, and thus displacement of resident brine. Via hydraulically conductive faults, brine may migrate upwards into shallower aquifers and lead to unwanted salinisation of potable groundwater resources. In the present study, we investigated different scenarios for a potential storage site in the Northeast German Basin using a three-dimensional (3-D) regional-scale model that includes four major fault zones. The focus was on assessing the impact of fault length and the effect of a secondary reservoir above the storage formation, as well as model boundary conditions and initial salinity distribution on the potential salinisation of shallow groundwater resources. We employed numerical simulations of brine injection as a representative fluid. Our simulation results demonstrate that the lateral model boundary settings and the effective fault damage zone volume have the greatest influence on pressure build-up and development within the reservoir, and thus intensity and duration of fluid flow through the faults. Higher vertical pressure gradients for short fault segments or a small effective fault damage zone volume result in the highest salinisation potential due to a larger vertical fault height affected by fluid displacement. Consequently, it has a strong impact on the degree of shallow aquifer salinisation, whether a gradient in salinity exists or the saltwater–freshwater interface lies below the fluid displacement depth in the faults. A small effective fault damage zone volume or low fault permeability further extend the duration of fluid flow, which can persist for several tens to hundreds of years, if the reservoir is laterally confined. Laterally open reservoir boundaries, large effective fault damage zone volumes and intermediate reservoirs significantly reduce vertical brine migration and the potential of freshwater salinisation because the origin depth of displaced brine is located only a few decametres below the shallow aquifer in maximum. The present study demonstrates that the existence of hydraulically conductive faults is not necessarily an exclusion criterion for potential injection sites, because salinisation of shallower aquifers strongly depends on initial salinity distribution, location of hydraulically conductive faults and their effective damage zone volumes as well as geological boundary conditions.

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Snezhko, V. L., D. M. Benin e N. V. Gavrilovskaya. "Salinisation of Reclaimed Agricultural Land in the Altai Territory: Cluster Analysis". Timiryazev Biological Journal, n. 2 (21 marzo 2023): 107–17. http://dx.doi.org/10.26897/2949-4710-2023-2-107-117.

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The Altai Territory occupies a leading position among the constituent entities of the Siberian Federal District in terms of arable land, of which more than 80% are located in the zone of unstable moisture. Irrigation is the predominant form of agricultural hydraulic reclamation in the region. The area of irrigated land is about 69 thousand hectares, of which almost 10% of the area has varying degrees of salinity in the 0‑100 cm layer. Prolonged irrigation and non-compliance with irrigation technologies can lead to salinisation of land. In the Russian Federation, all irrigation systems havecommon rules for collecting data on soil condition, conducting soil salinity surveys and laboratory processing of field research material. The analysis of irrigated agricultural land by the degree of its salinisation was carried out according to the data of the land reclamation cadastre for the period from 1 January 2013 to 1 January 2022. A model of the dynamics of highly and very highly saline areas was built, statistical estimates of the quality of the model were checked, and the average annual rate of increase in the area of saline areas was determined. The most likely causes of salinisation in irrigated areas were analysed. These are high groundwater levels and groundwater salinity, and high salinity of water used for irrigation. An analysis of the most likely causes of salinisation in irrigated areas was carried out, including high groundwater levels and salinity, and high salinity of water used for irrigation. The dynamics of areas with different groundwater levels, different salinities of groundwater and irrigation water are given. Based on the data from the beginning of 2022, a cluster analysis of the regions of the Altai Territory was carried out according to the degree of salinisation of agricultural land. The quality of the clustering was checked.

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Wilkinson, Kate, Tessa Chamberlain e Mike Grundy. "Investigation into salinisation in southwestern Queensland". ASEG Extended Abstracts 2004, n. 1 (dicembre 2004): 1–4. http://dx.doi.org/10.1071/aseg2004ab159.

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Barnett, Steve. "The looming threat of aquifer salinisation". ASEG Extended Abstracts 2006, n. 1 (dicembre 2006): 1–4. http://dx.doi.org/10.1071/aseg2006ab009.

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Jiang, Shan, Xuan Wu, Sichan Du, Qin Wang e Dawei Han. "Are UK Rivers Getting Saltier and More Alkaline?" Water 14, n. 18 (9 settembre 2022): 2813. http://dx.doi.org/10.3390/w14182813.

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River salinisation and alkalinisation have become one of the major environmental problems threatening the safety of global freshwater resources. With the accelerated climate change and aggravating anthropogenic influences, it is important to identify the trends and causes of river salinisation and alkalinisation so that better mitigation measures could be taken. This study has focused on the UK rivers because there has been insufficient investigation on this topic. To understand the salinisation and alkalinisation trends and causes of rivers in the UK over the past 20 years from a vertical (analysis of each river) and horizontal (comparison of all rivers) perspective, this study uses the Theil-Sen regression and Mann-Kendall test to deal with the trends of conductivity (proxy on salinisation) and pH (proxy on alkalinisation), obtains outliers of conductivity and pH by boxplot, and calculates the Pearson’s and the Kendall’s Tau correlation coefficients (α = 0.05) between the water quality data and the potential factors (potential road salting, normalized difference vegetation index (NDVI), river discharge, agricultural and urban lands). The results show that the UK rivers are becoming more alkaline with a median pH increase of 0.05 to 0.40, but less salty with a median conductivity decrease of 0.06 to 0.11 mS/cm. And the changes in conductivity and pH have seasonality and regionality, which shows that there are usually greater changes in trends and medians of them in winter or through reaches with more anthropogenic disturbance. Furthermore, from a vertical perspective, the conductivity of more than 50% of rivers in this study is negatively correlated with NDVI and river discharge, and positively correlated with potential road salting, and the pH of that is positively correlated with agricultural lands. While from a horizontal perspective, NDVI and agricultural lands are positively correlated with pH, and potential road salting and urban lands are positively correlated with conductivity. Therefore, road salting, urbanisation, agricultural lands, river discharge and vegetation cover can be considered to affect river salinisation and alkalinisation in the UK.

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Armour, RJ, e MF Viljoen. "An economic case for drainage for sustainable irrigation: Case studies in the lower Vaal and Riet catchments". South African Journal of Economic and Management Sciences 10, n. 4 (22 maggio 2014): 470–81. http://dx.doi.org/10.4102/sajems.v10i4.1060.

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Where evaporation exceeds precipitation salinisation is inevitable. This paper presents a multidisciplinary framework of the dynamic interactions between the hydrology, bio-physical and economics of irrigated agriculture in a semi arid area. Status quo drainage and cropping situations are compared to a scenario of increased drainage and leaching and subsequent higher value crops. Stochastically generated hydrology data fitted to a salinisation:yield production function is inputted in a crop enterprise budget (CEB) simulation model.Results show losses due to salinisation of up to R6 962/ha, which exceed the direct costs of installing drainage to control salinisation. Although feasible, farmers at this stage of degradation often do not have the financial ability to repay the loans. Where losses do not exceed the financial costs of drainage, soils are further degrading, higher value crops cannot be planted and potential benefits are lost to society, motivating a green box grant. A macro-economic analysis reveals that the potential benefits to society of drainage can repay the total cost of all necessary drainage in a short period of time.

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Akeroyd, M. D., G. R. Walker e M. B. Kendall. "Response of Eucalyptus largiflorens to floodplain salinisation". Water Science and Technology 48, n. 7 (1 ottobre 2003): 113–20. http://dx.doi.org/10.2166/wst.2003.0431.

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An analysis of the stable isotopes from the tree rings of Eucalyptus largiflorens on the Chowilla Floodplain was undertaken. This chronology of tree water use responses was compared to the known hydrological changes that have occurred due to the effects of river regulation. The isotope chronology indicates that E. largiflorens has always oscillated between groundwater and rain-derived soil water and river regulation has apparently had little effect on tree water sources over time. This result is surprising, but no doubt reflects the complexity of floodplain processes and interactions between trees, water and the landscape.

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Cañedo-Argüelles, Miguel, Ben J. Kefford, Christophe Piscart, Narcís Prat, Ralf B. Schäfer e Claus-Jürgen Schulz. "Salinisation of rivers: An urgent ecological issue". Environmental Pollution 173 (febbraio 2013): 157–67. http://dx.doi.org/10.1016/j.envpol.2012.10.011.

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González, Esther M. "Drought Stress Tolerance in Plants". International Journal of Molecular Sciences 24, n. 7 (31 marzo 2023): 6562. http://dx.doi.org/10.3390/ijms24076562.

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Florinsky, I. V., R. G. Eilers e G. W. Lelyk. "Prediction of soil salinity risk by digital terrain modeling in the Canadian prairies". Canadian Journal of Soil Science 80, n. 3 (1 agosto 2000): 455–63. http://dx.doi.org/10.4141/s99-093.

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Soil salinisation is a typical problem for the Canadian prairies. At macro-topographic scale, build-up of salts occurs in depressions. However, this relationship is not displayed on existing small-scale maps of soil salinity. To improve these maps, one can use a concept of accumulation, transition and dissipation zones of the landsurface. The concept allows one to reveal depressions (topographically expressed accumulation zones) using digital models of horizontal and vertical curvatures, or accumulation and mean curvatures derived from a digital elevation model. We applied the concept of accumulation, transition and dissipation zones to improve an existing small-scale map of the salinity risk index for the prairies and adjacent areas. A comparison of the old and the improved maps demonstrated that once data on depressions have been taken into account, areas marked by salinity risk decreased significantly. We suggest that the method used may prevent an overestimation in predictions of soil cover degradation due to salinisation. The method used can also reveal saline areas linked with discharges of saline aquifers. This is because sites marked by high discharges of groundwater usually relate to sites of intensive fracturing of geological materials, which are closely associated with topographically expressed accumulation zones. Key words: Digital terrain models, topography, soil salinisation, mapping

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Beatty, Stephen J., David L. Morgan, Mahmoud Rashnavadi e Alan J. Lymbery. "Salinity tolerances of endemic freshwater fishes of south-western Australia: implications for conservation in a biodiversity hotspot". Marine and Freshwater Research 62, n. 1 (2011): 91. http://dx.doi.org/10.1071/mf10100.

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Secondary salinisation represents an important threat to terrestrial and aquatic habitats throughout the world. In south-western Australia, widespread salinisation of waterways has caused large range reductions in the highly endemic freshwater fish fauna. We hypothesised that differences in the distributions of three fish species within the salinised Blackwood River would be related to their salinity tolerances. Galaxias occidentalis was widespread throughout the catchment, whereas Nannoperca vittata was restricted to the main channel and freshwater tributaries of the lower catchment, and Nannatherina balstoni was restricted to those tributaries and a perennial section of the main channel that received a considerable amount of fresh groundwater. Acute salinity tolerances (Effect Concentrations) of G. occidentalis and N. vittata were similar (EC50 ∼14.6 g L–1), but significantly greater than that of N. balstoni (EC50 ∼8.2 g L–1). The greater geographical range of G. occidentalis, compared with N. vittata, may be a consequence of the dispersal capability of the former species, and the lower salinity tolerance of N. balstoni contributes to its highly restricted range. The findings demonstrate that secondary salinisation has greatly impacted these freshwater fishes, and fresh groundwater refuges, predicted to decrease due to reduced rainfall, appear crucial in maintaining remnant populations.

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Jana, Atashi, e Gouri Sankar Bhunia. "Vegetation Cover Analysis Based on NDVI in Moushuni Island, Sundarban, India". International Journal for Research in Applied Science and Engineering Technology 10, n. 5 (31 maggio 2022): 2669–74. http://dx.doi.org/10.22214/ijraset.2022.42883.

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Abstract: Moushuni island is one of the island of Indian Sundarban, but changes of vegetation cover is occurred due to natural and anthropogenic activity. The aim of this paper is to emphasis the changes of vegetation cover between 2000 and 2020 of Moushuni island. Vegetation indices like Normalised Difference Vegetation Index (NDVI) is used to identify the changes of vegetation cover from 2000 to 2020. Based on NDVI value, the study area is classified into four classes -Dense vegetation, Sparse Vegetation(vegetated), No vegetation and Water. Result shows an overall increase of dense vegetation cover (8.1%) in the island. The percent of vegetated area coverage is decreased during the study period. The major cause of decrease vegetation may be attributed to increase of rural settlement and salinisation. Keywords: Moushuni, NDVI, Dense vegetation, Vegetated, Salinisation.

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Kijne, J. W. "Salinisation in irrigated agriculture in Pakistan: mistaken predictions". Water Policy 8, n. 4 (1 agosto 2006): 325–38. http://dx.doi.org/10.2166/wp.2006.045.

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This paper revisits data and information that was collected through field studies by the International Irrigation Management Institute (IIMI) in Pakistan in the early 1990s. Analysis of available data led in 1996 to the publication of an IIMI research report (Kijne, 1996) whose main conclusion was that current cropping intensities and groundwater usage in Pakistan's irrigated agriculture were not sustainable. Ten years on there is no evidence that this prediction came true and the paper questions why those predictions were wrong. Based on more recent field data and information, the water and salt balances for one of the experimental sites are recalculated. Reasons for the mistaken predictions include: lack of understanding of farmers' reactions to signs of salinity in their fields, insufficient knowledge of the actual groundwater usage and underestimating the leaching fractions. The difficulty in accurately determining the actual leaching fraction from easily measurable field parameters affects the prediction of salt accumulation in the soil. The conclusion that current practices are all right is conditional on maintaining sufficient downward fluxes in the soil profile. The paper ends with some general reflections on predictions for the future.

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Grujić, Gordana, Jovica Vasin e Milivoj Belić. "Soil salinisation in Vojvodina - the Republic of Serbia". Current Opinion in Environmental Sustainability 50 (giugno 2021): 149–58. http://dx.doi.org/10.1016/j.cosust.2021.03.015.

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Dehaan, R., e G. R. Taylor. "Image-derived spectral endmembers as indicators of salinisation". International Journal of Remote Sensing 24, n. 4 (gennaio 2003): 775–94. http://dx.doi.org/10.1080/01431160110107635.

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Abdelhafid, Youcef, Miled Zohra Rechachi e Amor Halitim. "Caractérisation géochimique des eaux d’irrigation de la palmeraie d’Oumache (oasis des Ziban, sud-est de l’Algérie)". Revue des sciences de l’eau 32, n. 1 (15 maggio 2019): 69–81. http://dx.doi.org/10.7202/1059881ar.

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Résumé L’ancienne palmeraie d’Oumache située à l’aval de Zab el Gharbi (ouest de Ziban-Biskra, sud-est de l’Algérie) connait aujourd'hui un déclin dû essentiellement à l’insuffisance de l’eau d’irrigation et à la remontée des eaux trop chargées de la nappe phréatique. De plus, le milieu endoréique très évaporant a accéléré le phénomène de salinisation du sol. Ce travail traite de la caractérisation géochimique des eaux (forage et nappe) utilisées pour l’irrigation en vue d’une meilleure gestion de l’irrigation. Les résultats montrent que l’eau de forage présente un risque élevé de salinisation des sols. La salinité est de type neutre, sulfaté calcique et magnésique. En revanche, les eaux de la nappe sont impropres à l’irrigation avec des risques très élevés de salinisation et d’alcalinisation des sol. Elles évoluent vers une voie saline neutre du type chloruré et sulfaté sodique (57 % des échantillons) à sulfaté et chloruré sodique. La calcite et le gypse ont tendance à précipiter, alors que l’halite et thenardite sont dissous par évaporation. La nappe s’écoule depuis la zone d’alimentation vers la sebkha de Chemoura qui constitue la zone d’accumulation. Pour remédier au problème, il est préconisé de mettre en place un plan de gestion durable de l’eau et de la salinité, comprenant notamment la réhabilitation du système de drainage de cette palmeraie afin d’évacuer les eaux salées. Enfin, l’extension de l’oasis devra prendre en considération cet aspect de gestion préventive en optant pour l’oued Djedi comme autre exutoire naturel.

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El Bastawesy, M., e R. Ramadan Ali. "The use of GIS and remote sensing for the assessment of waterlogging in the dryland irrigated catchments of Farafra Oasis in Egypt". Hydrology and Earth System Sciences Discussions 8, n. 6 (5 dicembre 2011): 10535–63. http://dx.doi.org/10.5194/hessd-8-10535-2011.

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Abstract. This paper investigates the interplay of the hydrogeological characteristics, soil properties and recent land reclamation projects on the distribution of waterlogging and salinisation within the Farafra Oasis. The multi-temporal remote sensing data and field observations show that new reclaimed areas have been recently cultivated in distant areas from the old agricultural land. These new cultivations have developed widespread water logging, seepage channels and soil salinisation. Analyses of the Shuttle Radar Topography Mission (SRTM) Digital Elevation Model (DEM) showed that both old and new agricultural areas are located within same closed drainage basin. The fluvial channels of these catchments, which were developed during wet climatic pluvial have largely been obliterated by the prevailing aridity and often buried under aeolian deposits. However, the new cultivations have been developed on the fingertips of these fluvial channels, while the old fields occupy the low level playas. The soil of the new cultivated areas are mainly lithic with a high calcium carbonate content, thus limiting the downward percolation of excess irrigation water and therefore develop perched water table and seepage through the paleo-channels. The automatically extract drainage networks from DEM are resembling fluvial patterns and coincide with the seepage channels slowly heading toward old cultivation. The inactive alluvial channels and landforms have to be considered when planning for new cultivation in dryland catchments to better control waterlogging and salinisation hazard. It is highly recommended that newly developed seepage-channels have to be detected and intercepted before reaching old agriculture areas. Therefore, the "dry-drainage" concept can be implemented as the seepage water can be conveyed into a nearby playas reserved for evaporation.

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Cunillera-Montcusí, David, Meryem Beklioğlu, Miguel Cañedo-Argüelles, Erik Jeppesen, Robert Ptacnik, Cihelio A. Amorim, Shelley E. Arnott et al. "Freshwater salinisation: a research agenda for a saltier world". Trends in Ecology & Evolution 37, n. 5 (maggio 2022): 440–53. http://dx.doi.org/10.1016/j.tree.2021.12.005.

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Howlett, A., M. J. Roach e J. E. Reid. "Geophysical Characteristics of Salinisation at Cape Portland, NE Tasmania". ASEG Extended Abstracts 2001, n. 1 (dicembre 2001): 1–4. http://dx.doi.org/10.1071/aseg2001ab058.

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Howlett, A., M. J. Roach e J. E. Reid. "Geophysical Characteristics of Salinisation at Cape Portland, NE Tasmania". Exploration Geophysics 32, n. 3-4 (settembre 2001): 214–18. http://dx.doi.org/10.1071/eg01214.

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Schofield, N. J., e J. K. Ruprecht. "Regional analysis of stream salinisation in southwest Western Australia". Journal of Hydrology 112, n. 1-2 (dicembre 1989): 19–39. http://dx.doi.org/10.1016/0022-1694(89)90178-9.

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Ghassemi, F., A. J. Jakeman e H. A. Nix. "Human induced salinisation and the use of quantitative methods". Environment International 17, n. 6 (gennaio 1991): 581–94. http://dx.doi.org/10.1016/0160-4120(91)90170-u.

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Ruprecht, John, Tim Sparks, Ning Liu, Bernard Dell e Richard Harper. "Using reforestation to reverse salinisation in a large watershed". Journal of Hydrology 577 (ottobre 2019): 123976. http://dx.doi.org/10.1016/j.jhydrol.2019.123976.

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Feitz, Andrew J., e Sven Lundie. "Soil salinisation: a local life cycle assessment impact category". International Journal of Life Cycle Assessment 7, n. 4 (luglio 2002): 244–49. http://dx.doi.org/10.1007/bf02978880.

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Mouatassime Sabri, El, Ahmed Boukdir, Ismail Karaoui, Abdelkrim Arioua, Rachid Messlouhi e Abdelkhalek El Amrani Idrissi. "Modelling soil salinity in Oued El Abid watershed, Morocco". E3S Web of Conferences 37 (2018): 04002. http://dx.doi.org/10.1051/e3sconf/20183704002.

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Soil salinisation is a phenomenon considered to be a real threat to natural resources in semi-arid climates. The phenomenon is controlled by soil (texture, depth, slope etc.), anthropogenic factors (drainage system, irrigation, crops types, etc.), and climate factors. This study was conducted in the watershed of Oued El Abid in the region of Beni Mellal-Khenifra, aimed at localising saline soil using remote sensing and a regression model. The spectral indices were extracted from Landsat imagery (30 m resolution). A linear correlation of electrical conductivity, which was calculated based on soil samples (ECs), and the values extracted based on spectral bands showed a high accuracy with an R2 (Root square) of 0.80. This study proposes a new spectral salinity index using Landsat bands B1 and B4. This hydro-chemical and statistical study, based on a yearlong survey, showed a moderate amount of salinity, which threatens dam water quality. The results present an improved ability to use remote sensing and regression model integration to detect soil salinity with high accuracy and low cost, and permit intervention at an early stage of salinisation.

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31

Wedderburn, Scotte D., Keith F. Walker e Brenton P. Zampatti. "Salinity may cause fragmentation of hardyhead (Teleostei: Atherinidae) populations in the River Murray, Australia". Marine and Freshwater Research 59, n. 3 (2008): 254. http://dx.doi.org/10.1071/mf07205.

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Salinisation in lowland areas of the Murray–Darling Basin, Australia, has had noticeable effects on fish. The endangered endemic Murray hardyhead Craterocephalus fluviatilis is distributed patchily and confined mainly to saline waters (0.4–20 g L–1), whereas the unspecked hardyhead C. stercusmuscarum fulvus has a more continuous distribution but is absent from high salinities (>10). Osmoregulation was compared in these two congeners and an estuarine atherinid, the small-mouth hardyhead Atherinosoma microstoma, over a wide salinity range (0.03–85). All three species are euryhaline, although the osmoregulatory ability of C. s. fulvus falters above ~35 salinity. In low salinity (<1), C. fluviatilis is a better osmoregulator than A. microstoma, but both species tolerate hypersaline conditions (85). These data imply a physiological reason for the predominance of C. fluviatilis in inland saline waters, but the reasons for its absence from freshwater habitats (<0.4) remain unclear. The findings have implications for other freshwater fish, especially populations of closely related species, subjected to the effects of salinisation or other stressors.

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32

Amzallag, G. Nissim. "Influence of Periodic Fluctuations in Root Environment on Adaptation to Salinity in Sorghum bicolor". Functional Plant Biology 24, n. 5 (1997): 579. http://dx.doi.org/10.1071/pp96018.

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In Sorghum bicolor (L.) Moench, a 3-week exposure to 75 mM NaCl induced the ability to grow at 300 mm NaCl, a lethal concentration for non-pretreated plants. This property was defined as adaptation to salinity. The chemical composition of the root medium was periodically modified during the 3-week maturation of the adaptation response. Two daily 1-h interruptions of the salinisation treatment were sufficient to prevent the initiation of the adaptation process, while two daily 1-h modifications of the external NaCl concentration only disturbed its completion. Moreover, the effect of a short interruption in the salinisation treatment depended on the time of day it occurred. The rate of growth was not directly influenced by the water content or the amount of Na+ ions accumulated in the shoot; it appears to be a function of the mode of response of the plant to salinity. It is concluded that the nature of the plant response to salinity is controlled by the roots, which display a circadian fluctuation in sensitivity to the ionic and osmotic components of the soil environment.

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33

Bak, Malgorzata, Dariusz Halabowski, Adrian Kryk, Iga Lewin e Agnieszka Sowa. "Mining salinisation of rivers: its impact on diatom (Bacillariophyta) assemblages". Fottea 20, n. 1 (1 aprile 2020): 1–16. http://dx.doi.org/10.5507/fot.2019.010.

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34

Khayrulina, Elena, Anna Bogush, Larisa Novoselova e Natalya Mitrakova. "Properties of Alluvial Soils of Taiga Forest under Anthropogenic Salinisation". Forests 12, n. 3 (10 marzo 2021): 321. http://dx.doi.org/10.3390/f12030321.

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The environmental impact of deposit development can be indirect and can cause combined geochemical processes in ecosystems. These must be taken into consideration under environmental forecasting and environmental risk assessment. Soil degradation in the Taiga Forest is considered, within the area of Verkhnekamskoye potash deposit (Russia), as an example of such environmental transformation. Here, the mechanism and characteristics of the anthropogenic salinisation of alluvial soils under potash deposit development are newly described. It was found that there is a strong anthropogenic impact of the potash industry on valley soils where the contaminated Na-Cl groundwater discharges or is close to the surface. The valley soils are characterised by high salinity, and the sum of toxic salts in soils has reached 26%. Alluvial gley humic clay chloride saline soil (Gleyic Fluvisols (Salic, Loamic, Technic)) and secondary solonchak on alluvial humic clay soil sulphate-chloride gypsum-containing surface-gleyed (Chloridic Gleyic Fluvic Solonchak (Hypersalic, Loamic, Technic)) were formed in hydromorphic conditions. Morphological, physicochemical and mineralogical analyses were carried out. Under hydromorphic conditions, Chloridic Gleyic Fluvic Solonchak (Hypersalic, Loamic) was described to show a hydrotroillite layer and reddish-yellow iron-rich precipitates on its surface. The top soil horizon has the highest content of iron minerals (up to 84.9%) and Fe-bearing plant residues (up to 20%). Additionally, the spongy and gel-like organic materials, as well as the siliceous remains of diatoms, are enriched in Ca, Fe, Cl, K, Na, S and P. The lower soil horizon consists of black gel-like phases and hydrogen sulphide settings with a high content of plant residues. The insoluble part of the samples contains up to 84% hydrogoethite. The sources of iron in soils and bottom sediments include the iron-enriched Sheshma sediments speckled rocks, slurry material, halite wastes and soil minerals of alluvial gley soils.

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35

Wilkinson, Kate, Tessa Chamberlain e Mike Grundy. "The role of geophysics in understanding salinisation in Southwestern Queensland". BUTSURI-TANSA(Geophysical Exploration) 58, n. 1 (2005): 78–85. http://dx.doi.org/10.3124/segj.58.78.

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36

Wilkinson, Kate, Tessa Chamberlain e Mike Grundy. "The role of geophysics in understanding salinisation in Southwestern Queensland". Exploration Geophysics 36, n. 1 (marzo 2005): 78–85. http://dx.doi.org/10.1071/eg05078.

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37

Jacobson, Gerry. "Guest Editor’s Preface: Groundwater processes in land and water salinisation". Hydrogeology Journal 5, n. 1 (gennaio 1997): 4–5. http://dx.doi.org/10.1007/s10040-997-0009-z.

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38

Mausbach, William E., e Andrew R. Dzialowski. "Salinisation reduces biodiversity in neighbouring freshwater patches in experimental metacommunities". Freshwater Biology 65, n. 3 (13 dicembre 2019): 592–604. http://dx.doi.org/10.1111/fwb.13457.

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39

Kašovská, Kamila, Łukasz Pierzchała, Edyta Sierka e Barbara Stalmachová. "Impact of the Salinity Gradient on the Mollusc Fauna in Flooded Mine Subsidences (Karvina, Czech Republic)". Archives of Environmental Protection 40, n. 1 (1 marzo 2014): 87–99. http://dx.doi.org/10.2478/aep-2014-0007.

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Abstract This paper presents the impact of salinisation on the aquatic mollusc fauna in flooded mine subsidences in the Karvina region (Czech Republic). The results of the previous research on salinity in flooded mine subsidences show that some of them contain a high content of dissolved inorganic substances (above 1000 mg·l-1). These substances can affect the vegetation and animals occurring in the water and the surrounding area. The phylum of Mollusca was selected as a model group for the fieldwork as it includes species with the proven bioindication potential. The occurrence of aquatic mollusc species was studied at 10 sites. The sites were selected based on the content of dissolved substances (the salinity gradient from <500 to >1000 mg·l-1. A total of 12 aquatic mollusc species were found, including one species identified as a potential bioindicator of the negative effect of salinisation on aquatic biota. The analysis showed statistically significant positive correlations between the content of dissolved inorganic substances and the presence of alien species Potamopyrgus antipodarum (J.E. Gray, 1843). The gradient of salinity significantly affects the species composition of the mollusc fauna in flooded mine subsidences and may affect the biodiversity of this group.

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40

Jiang, Jinyuan, Huibin Yu, Beidou Xi, Fansheng Meng, Yuexi Zhou e Hongliang Liu. "UV - visible spectroscopic properties of dissolved fulvic acids extracted from salined fluvo-aquic soils in the Hetao Irrigation District, China". Soil Research 49, n. 8 (2011): 670. http://dx.doi.org/10.1071/sr11213.

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The elemental composition and the UV–visible spectroscopic properties of dissolved fulvic acids (FA) extracted from salined fluvo-aquic soils in the Hetao Irrigation District were examined to evaluate the humification degree of FA and salinisation processes of soils. Composite soil samples of different depths (0–20, 20–40, 40–60, 60–80 cm) were collected from four native halophyte soils [communities Salicornia europaea (CSE), Suaeda glauca (CSG), Kalidium foliatum (CKF), Sophora alopecuroides (CSA)] and two furrow-irrigated fields [corn (CFD), wheat (WFD)] along a saline impact gradient. Seven humification indices (HIXs: C/N, SUVA, E2/E3, E2/E4, S275–295, S350–400, and S250–400), deduced from elemental analysis and UV–visible spectroscopy of FAs, were used to evaluate the humification degree. The humification degree of FA from the WFD soil was the highest, followed by CFD, CSA, CKF, CSG, and CSE. There were significant relationships between the seven HIXs (P < 0.05). The exchangeable sodium percentage (ESP) exhibited close correlations with the seven HIXs, and the humification degree increased with decreasing ESP. The HIX can not only indicate the humification degree of soil organic matter but also characterise the salinisation processes of soils.

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41

Bethune, Matthew. "Towards effective control of deep drainage under border-check irrigated pasture in the Murray-Darling Basin: a review". Australian Journal of Agricultural Research 55, n. 5 (2004): 485. http://dx.doi.org/10.1071/ar03192.

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High watertables and land salinisation threaten the sustainability and prosperity of the irrigated dairy industry in the Murray–Darling Basin of Australia. High watertables and salinisation result from excessive deep drainage. Spatial and temporal trends in deep drainage data pertinent to the dairy industry in the Murray–Darling Basin are reviewed with a view towards reducing deep drainage. The reviewed data indicate that deep drainage under border-check irrigated pasture is generally greater than the leaching requirement and can be reduced without affecting pasture growth. Deep drainage through levee soils is likely to contribute significantly to regional groundwater. Consideration needs to be given to the appropriateness of using the border-check irrigation system on levee soils. Pressurised irrigation systems or land use change may be required to reduce deep drainage under these soils. The majority of deep drainage under floodplain soils occurs during winter and spring, when rainfall exceeds pasture water use. Developing a soil water deficit prior to winter will reduce deep drainage. This can be achieved by ending the irrigation season earlier. A later start to the irrigation season also offers potential to divert more winter rainfall into evapotranspiration rather than deep drainage.

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42

George, Richard, Jonathan Clarke e Pauline English. "Modern and palaeogeographic trends in the salinisation of the Western Australian wheatbelt: a review". Soil Research 46, n. 8 (2008): 751. http://dx.doi.org/10.1071/sr08066.

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The Western Australian wheatbelt contains vast areas of agricultural land underlayed by saline and deeply weathered regolith derived from Archaean rocks and recent sediments. The region has been geologically stable since the late Permian, although the Archaean basement sustained some movement during the break-up of Gondwanaland and the northward drift of Australia from Antarctica. During the Early Cretaceous, Eocene and more recently, the wheatbelt region’s weathered mantle has been successively eroded by rivers. The palaeovalleys have been infilled with terrestrial and marine sediments, and subjected to ongoing deep weathering. During the Pliocene and Quaternary the region experienced alternating arid and wetter climates. These cyclic episodes influenced regolith development, affected vegetation species and catchment water balances, and also promoted the accumulation of massive volumes of salt. In more recent times, these salt stores have interacted with vegetation, soils, surface water bodies, and groundwater systems and left a distinctive and pervasive legacy in the landscape. Salinisation was manifest in the wheatbelt from as long ago as 2.8 Ma, concentrating in valley floors as arid and wetter cycles prevailed and while the continent migrated northwards. Today, agricultural development has altered the water balance on 20 Mha of cleared farmland. As a result, salinity is spreading, further degrading 300 000 ha of variably saline landscape that existed before the arrival of Europeans, and affecting an additional 1.1 Mha of formerly arable land. Unchecked by reduced rainfall or human-induced changes to the water balance, salinity may expand even further, potentially affecting 1.7–3.4 Mha of the wheatbelt’s agricultural land and its unique natural resources. This paper reviews the palaeogeography and palaeoclimates of the region and its hydrogeology and examines the nature of its susceptibility to salinisation. It poses questions about the relationship between palaeo-salinity and contemporary salinity, seeking geomorphic evidence to indicate whether salinity is likely to expand beyond extant palaeo-salinity markers. Finally, it considers the likely timeframes involved in salinisation and whether clearing-induced salinity will follow patterns similar to those observed from past saline episodes in the region.

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43

Overton, I. C., I. D. Jolly, P. G. Slavich, M. M. Lewis e G. R. Walker. "Modelling vegetation health from the interaction of saline groundwater and flooding on the Chowilla floodplain, South Australia". Australian Journal of Botany 54, n. 2 (2006): 207. http://dx.doi.org/10.1071/bt05020.

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The native riparian vegetation communities on the Chowilla floodplain in the lower River Murray in South Australia are suffering severe declines in health, particularly the Eucalyptus camaldulensis Dehnh. (red gum) and Eucalyptus largiflorens F.Muell. (black box) communities. The primary cause of the decline is salinisation of the floodplain soils caused by increased rates of groundwater discharge and hence increased movement of salt up into the plant root zone. The salinity is driven by a lack of flooding and rising saline groundwater tables. Rises in the naturally saline groundwater levels are due to the effects of river regulation from Lock 6 and high inflows from regional groundwater levels increased by Lake Victoria to the east. River regulation has also led to reduced frequency and duration of the floods that leach salt from the plant root zone and supply fresh water for transpiration. The frequency of medium-sized floods occurring on Chowilla has been reduced by a factor of three since locking and water extractions were commenced in the 1920s to provide reliable water for urban and agricultural use. The soil salinisation on the floodplain was modelled by using a spatial and temporal model of salt accumulation from groundwater depth, groundwater salinity, soil type and flooding frequency. The derived soil water availability index (WINDS) is used to infer vegetation health and was calibrated against current extent of vegetation health as assessed from fieldwork and satellite image analysis. The modelling work has shown that there is a severe risk to the floodplain vegetation from current flow regimes. This paper estimates that 65% (5658 ha) of the 8600 ha of floodplain trees are affected by soil salinisation matching a field survey of vegetation health in 2003 (Department of Environment and Heritage 2005a), compared with 40% in 1993 (Taylor et al. 1996). Model results show that the best management option for Chowilla is lowering the groundwater down to 2 m below current levels, which predicts an improvement in the health of the floodplain tree species from 35 to 42%.

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44

Xajiev, M. X., e M. M. Atadjanova. "Agroecological aspects of the development of a polisher for washing salts of highly saline soils". IOP Conference Series: Earth and Environmental Science 1076, n. 1 (1 agosto 2022): 012063. http://dx.doi.org/10.1088/1755-1315/1076/1/012063.

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Abstract The current water shortages in the region exacerbate this problem and require a reduction in water losses. Therefore, alternative use of water resources for soil salinisation is currently one of the most important problems in agriculture. As a result of the creation, development and implementation in farms of a polisher for washing highly saline soils, it leads to an increase in the yield and quality of cultivated products.

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45

Lawrie, Angus D'Arcy, Jennifer Chaplin e Adrian Pinder. "Corrigendum to: Biology and conservation of the unique and diverse halophilic macroinvertebrates of Australian salt lakes". Marine and Freshwater Research 72, n. 11 (2021): 1695. http://dx.doi.org/10.1071/mf21088_co.

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This study synthesises information on the biology of the unique and diverse halophilic macroinvertebrates of Australian salt lakes, focusing on gastropods and crustaceans. This information is needed to evaluate and manage the threats posed to these invertebrates by increased periods of drought and secondary salinisation. Most of these species are endemic to Australian salt lakes, and some have adapted to extreme conditions (e.g. salinities >100gL–1 and pH

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46

Panagea, I. S., I. N. Daliakopoulos, I. K. Tsanis e G. Schwilch. "Evaluation of soil salinity amelioration technologies in Timpaki, Crete: a participatory approach". Solid Earth Discussions 7, n. 4 (6 ottobre 2015): 2775–805. http://dx.doi.org/10.5194/sed-7-2775-2015.

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Abstract. Soil salinity management can be complex, expensive and time demanding, especially in arid and semi-arid regions. Besides taking no action, possible management strategies include amelioration and adaptation measures. Here we use the World Overview of Conservation Approaches and Technologies (WOCAT) framework for the systematic analysis and evaluation of soil salinisation amelioration technologies in close collaboration with stakeholders. The participatory approach is applied in the RECARE Project Case Study of Timpaki, a semi-arid region in south-central Crete (Greece) where the main land use is horticulture in greenhouses irrigated by groundwater. Excessive groundwater abstractions have resulted in a drop of the groundwater level in the coastal part of the aquifer, thus leading to seawater intrusion and in turn to soil salinisation. The documented technologies are evaluated for their impacts on ecosystem services, cost and input requirements using a participatory approach and field evaluations. Results show that technologies which promote maintaining existing crop types while enhancing productivity and decreasing soil salinity are preferred by the stakeholders. The evaluation concludes that rain water harvesting is the optimal solution for direct soil salinity mitigation, whereas green manuring and the use of biological agents can support increasing production/efficiency and improving soil properties.

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47

Burger, F., e A. Čelková. "Salinity and sodicity hazard in water flow processes in the soil". Plant, Soil and Environment 49, No. 7 (10 dicembre 2011): 314–20. http://dx.doi.org/10.17221/4130-pse.

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This paper presents the results of the distribution of salinity characteristics (electrical conductivity and sodium adsorption ratio) of groundwater, and based on the results, it reports the evaluation of the salinity and sodicity hazards in the fluctuation processes of shallow mineralised groundwater, or in the processes if such groundwater is used for irrigation. The issue was studied for the soil-water environment in the south-east of the Danube Lowlands for the period 1991 to 1994. The measured data and data taken from archives were processed in the form of graphical attachments (appendixes, supplements, graphical documentation) – maps, by means of the kriging interpolation method. Groundwater in the area in question is classified as highly mineralised with a high hazard of salinisation of the subsurface soil environment. The average annual values of the electrical conductivity of groundwater ranged from 600 to 2100 µS/cm in the examined period. The sodium adsorption ratio values ranged from 1.7 to 22.0 and indicate low, medium to high sodium salinisation of the environment due to groundwater. The distribution of electrical conductivity and sodium adsorption ratio on the regional scale can serve as a reference basis for the evaluation of changes in the groundwater salinity after 1994.

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48

Rose, D. A., F. Konukcu e J. W. Gowing. "Effect of watertable depth on evaporation and salt accumulation from saline groundwater". Soil Research 43, n. 5 (2005): 565. http://dx.doi.org/10.1071/sr04051.

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When the evaporative demand is greater than the ability of the soil to conduct water in the liquid phase, the soil profile above a watertable exhibits a liquid−vapour discontinuity, known as the evaporation front, that affects the depth of salinisation and the rate of evaporation. We conducted experiments on a sandy loam with shallow saline watertables under high isothermal evaporative demand (24 mm/day), monitoring rates of evaporation from the soil and upward movement of groundwater, and observing profiles of soil water and salinity over periods of up to 78 days. Three zones were distinguished in the soil profile: a zone of liquid flow above the watertable, a zone of vapour flow close to the surface, and an intermediate transition zone in which mixed liquid−vapour flow occurred. The vapour-flow zone above the evaporation front appeared after a few days and progressed downward to depths of 40, 60, and 120 mm, while eventual steady-state rates of evaporation were 1.3, 1.1, and 0.3 mm/day for watertable depths of 300, 450, and 700 mm, respectively. Salts mainly accumulated in the transition zone, suggesting that the depth of the evaporation front should be a criterion to locate and prevent salinisation as a result of capillary flow from a watertable in arid regions.

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49

Zhu, JunTao, JingJie Yu, Ping Wang, Qiang Yu e Derek Eamus. "Variability in groundwater depth and composition and their impacts on vegetation succession in the lower Heihe River Basin, north-western China". Marine and Freshwater Research 65, n. 3 (2014): 206. http://dx.doi.org/10.1071/mf13082.

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Plant-community structure and groundwater attributes were investigated in Ejina Delta in north-western China to understand spatial variability of groundwater depth and composition and their impacts on vegetation succession. Geostatistical methods and ordination analysis were performed to analyse the data. In addition, we tried to obtain vegetation successional series by using an approach of spatial sequences instead of temporal sequences. The findings of the present study were as follows: (1) the coefficient of variation for groundwater depth (GWD), salinity (SAL), total dissolved solids (TDS), electrical conductivity (EC), pH, Ca2+, Mg2+, K+, Na+, SO42–, HCO3–, NO3–, Cl– and F– ranged from 0.04 to 1.53; (2) GWD, Mg2+, TDS, EC, Ca2+, HCO3–, NO3– and pH showed strong spatial autocorrelation, whereas K+ and SAL showed moderate spatial autocorrelation; (3) canonical correspondence analysis revealed that groundwater heterogeneity, especially GWD, followed by pH, SAL, TDS, EC and HCO3–, had an important impact on vegetation succession, and thus showed a prevalence of groundwater attributes-based niche differentiation among plant communities; and (4) there were two vegetation successional processes (drought and salinisation) in the lower Heihe River Basin, and salinisation processes increased with drought processes. Our results indicated that high spatial variability of groundwater attributes contributes to promoting maintenance of species and landscape diversity in the lower Heihe River Basin.

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50

Boon, Paul I., Perran Cook e Ryan Woodland. "The Gippsland Lakes: management challenges posed by long-term environmental change". Marine and Freshwater Research 67, n. 6 (2016): 721. http://dx.doi.org/10.1071/mf14222.

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The Gippsland Lakes, listed under the Ramsar Convention in 1982, have undergone chronic salinisation since the cutting in 1889 of an artificial entrance to the ocean to improve navigational access, exacerbated in the mid–late 20th century by increasing regulation and extraction of water from inflowing rivers. Both developments have had substantial ecological impacts: a marked decline in the area of reed (Phragmites australis) beds; the loss of salt-intolerant submerged taxa such as Vallisneria australis, causing a shift to a phytoplankton-dominated system in Lake Wellington; and, nearer the entrance, an expansion in the area of seagrasses. Mangroves (Avicennia marina) first appeared in the late 1980s or early 1990s. Since 1986 recurring blooms of Nodularia spumigena have led to loss of recreational amenity and to the periodic closure of recreational and commercial fisheries. Changes to hydrological and salinity regimes have almost certainly shifted the contemporary fish community away from the pre-entrance state. Rises in eustatic sea levels and increases in storm surges will exacerbate the issue of chronic salinisation. Whether or not managers choose to intervene to prevent, or at least minimise, ongoing environmental change will inevitably prove controversial, and in some cases no socially or technologically feasible solutions may exist.

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