Moderate Saline Water Research Articles

Vegetative and Reproductive Response of Olive Cultivars to Moderate Saline Water Irrigation

Selected superior olive cultivars cultivated on a large scale in various countries in the Mediterranean region were tested in a special saline irrigation experimental plot established in 1997 in the center of the semiarid Israeli Negev area. The plot comprised two subplots containing the same 12 olive cultivars in a mirror image design. One subplot was drip-irrigated with tap water (1.2 dS·m−1) and the second with moderate saline water (4.2 dS·m−1). All cultivation practices applied to the two subplots were similar in terms of fertilization, irrigation, soil leaching, and so on. The present study summarizes the vegetative and reproductive response of the tested olive cultivar trees during the 5 years after they reached maturation and full yield. Evaluation of trunk growth, olive yield, oil percentage, olive oil yield, and fatty acid composition of the oil, sodium and chloride leaf levels, and soil fractions up to 90 cm enabled characterization and comparison of the horticultural performance of the various olive cultivars intensively cultivated with the two tested irrigation treatments. The data clearly showed a significant difference between the tested cultivars in terms of growth, yield, and oil parameters. Grouping the tested cultivars in terms of olive oil production yielded the following three groups: Group A—‘Barnea’, ‘Maalot’, and ‘Picholin’—their average oil yield ranged from 8 to 10 kg/tree; Group B—‘Souri’, ‘Frantoio’, ‘Leccino’, ‘Arbequina’, ‘Picual’, ‘Kalamata’, ‘Koroneiki’, and ‘Picholin di Morroco’—their average oil yield ranged from 5 to 8 kg/tree; and Group C—‘Picudo’—ranged from 3 to 4 kg/tree. Saline irrigation treatment at 4.2 dS·m−1 demonstrated only a low rate of retardation effect on growth or yield of olive trees compared with water at 1.2 dS·m−1 of the same cultivar in each subplot. The data obtained from the present study suggest that efficient productive cultivation of mature olive cultivars in Israeli Negev semiarid conditions, irrigated with moderate saline water, is closely related to proper soil leaching methodology and maintaining the soil electrical conductivity level in the root zone in a range lower than 6 dS·m−1.

Yield and fruit quality of industrial tomato under saline irrigation

Industrial tomato is the most important vegetable crop of the Brazilian agribusiness. Few researches have evaluated the tolerance of this crop to saline stress. In this study, the effects of five levels of salinity of the irrigation water (1, 2, 3, 4, and 5 dS m-1) and two equivalent proportions of Na:Ca:Mg (1:1:0.5 and 7:1:0.5) were tested on yield and quality of fruits of industrial tomato, cultivar IPA 6. Seedlings were transplanted in rhizotrons and grown under plastic covering until fruit ripening. Volume of water for daily irrigations was determined by the difference between the applied and drained volume in the previous irrigation. Unitary increase of water salinity above 1 dS m-1 reduced the commercial and total yield by 11.9 and 11.0%, respectively, and increased the concentration of soluble solids and the titratable acidity of the fruits by 13.9 and 9.4%, respectively. The increase of the proportion of sodium reduced the total and marketable yield, the number of marketable fruits and pulp yield. Water of moderate salinity, with low concentration of sodium, can be used in the irrigation of the industrial tomato, without significant yield losses.

Ecology of a novel Synechococcus clade occurring in dense populations in saline Antarctic lakes

MEPS Marine Ecology Progress Series Contact the journal Facebook Twitter RSS Mailing List Subscribe to our mailing list via Mailchimp HomeLatest VolumeAbout the JournalEditorsTheme Sections MEPS 291:65-80 (2005) - doi:10.3354/meps291065 Ecology of a novel Synechococcus clade occurring in dense populations in saline Antarctic lakes L. M. Powell1, J. P. Bowman1,*, J. H. Skerratt2, P. D. Franzmann3, H. R. Burton4 1Australian Food Safety Centre for Excellence, School of Agricultural Science, University of Tasmania, Private Bag 54, Hobart, Tasmania 7001, Australia2CSIRO Marine Research Division, Castray Esplanade, Hobart, Tasmania 7001, Australia3CSIRO Land and Water Division, Underwood Avenue, Floreat Park, Perth, Western Australia 6014, Australia4Australian Antarctic Division, Channel Highway, Kingston, Tasmania 7050, Australia *Corresponding author. Email: john.bowman@utas.edu.au ABSTRACT: The seasonal distribution and abundance of Synechococcus-like morphotypes was investigated in meromictic lakes and coastal areas of the Vestfold Hills, Antarctica. Populations were monitored by flow cytometry utilising phycoerythrin content and small cell size to distinguish the cells from other phytoplankton. In Ace Lake, the Synechococcus bloom commenced in September at the water temperature minimum and peaked in late November. Populations (up to 8 × 106 cells ml–1) were maximally stratified at a depth of 11 m, corresponding to waters which were supersaturated with oxygen, high in phosphate and which received >5 µmol photons m–2 s–1 of light. At this depth, salinity (30 g kg–1) was constant throughout the year and temperature ranged from 4.5°C in October to 10.5°C in February. In late November, high numbers of Synechococcus cells also occurred in the moderate salinity water bodies Lake Abraxas and Pendant Lake (salinity 16.5 to 31.0 g kg–1), with populations highly stratified in Lake Abraxas (up to 1.5 × 107 cells ml–1, temperature 8.0°C, salinity 20.3 g kg–1) but less so in the colder waters of Pendant Lake (max. 1.5 × 107 cells ml–1, temperature 0.1 to 1.1°C, salinity 31.0 g kg–1). Synechococcus populations did not occur in brackish, coastal marine or hypersaline water bodies in the Vestfold Hills. Populations appear to be controlled primarily by temperature and to a lesser extent by light availability and grazing. Characterization of non-axenic cultures indicated that the Antarctic lake Synechococcus populations were similar to other polar picocyanobacteria in terms of cardinal growth temperatures (minimum, optimum, maximum: Tmin –17.0°C, Topt 19.8°C, Tmax 29.5°C) and slow growth. Related only peripherally to Synechococcus sp. Cluster 5.2 (Marine Cluster B), the Antarctic strains represent a unique and highly adapted clade in the stable water columns of some saline Antarctic lakes. KEY WORDS: Synechococcus · Antarctica · Meromictic lakes · Marine ecosystems Full text in pdf format PreviousNextExport citation RSS - Facebook - Tweet - linkedIn Cited by Published in MEPS Vol. 291. Online publication date: April 28, 2005 Print ISSN: 0171-8630; Online ISSN: 1616-1599 Copyright © 2005 Inter-Research.

The potential role of brackish water desalination within the Egyptian water supply matrix

Fresh water supply to some remote desert areas in Egypt represents one of the major constraint to development of such areas. The current conventional water supply to remote communities includes pipelines and transportation means such as trucks. However, such methods seem to be very expensive, especially for very long distances (larger than 150 km). The presence of brackish water of moderate salinity (2000–6000 mg/l) in some of these areas can present an economic and reliable fresh water supply, if an appropriate desalination scheme is adopted. In this paper, the potential role of brackish water as a source of fresh water in Egypt is discussed. Key problems related to brackish water desalination experience in Egypt are outlined. Further, relevant brackish water technical and economic indicators are presented. A case study for brackish water desalination using reverse osmosis (RO) scheme is presented to elucidate its feasibility as compared to other water supply options. Further, planning guidelines for brackish water desalination are presented. The paper is concluded with the economic feasibility for large-scale RO desalination system for the presented case.

Desalting of subsurface water using spiral-wound reverse osmosis (RO) system: technical and economic assessment

Subsurface water rise is a major problem in Kuwait. The impact of this problem is manifested in surface water ponds, cracks in buildings, flooded basements and damaged roads. Dewatering this water of moderate salinity is necessary. Being in an arid area with very limited water resources, treatment and recycling of the subsurface water could be very important to a country like Kuwait. For this purpose, a pilot study was carried out by KISR to desalinate the subsurface water using the reverse osmosis (RO) technique. The main aim of this study is to assess the viability and economic feasibility of using RO technology. This paper outlines the results of over 8000 operating hours performance data of an RO plant utilizing spiral-wound membranes (SW) used to desalinate subsurface water with TDS of about 11,000 mg/1 and an economic feasibility evaluation. Results indicate that the (SW) RO system is a viable technique to desalinate this type of water. The improvements in TDS, COD and BOD were 99%, 96% and 42%, respectively. The economic feasibility evaluation indicates that the unit cost of desalting subsurface water by RO is 0.235 KD/m 3 (0.776 US$/m 3), which is considered to be economically feasible for a small-scale plant.

Subsoil hydraulic conductivity estimates for the Lower Macquarie Valley

Field saturated hydraulic conductivity was measured in situ, at two depths in the B horizon, on irrigated soils in the Lower Macquarie Valley. Measurements were made with constant head well permeameters, using the single-head method, and water of moderate sodicity and high salinity. The hydraulic conductivity data were log-normally distributed for all soil groups and there were significant differences between some of these soil groups in mean hydraulic conductivity. Three soils exhibited significant differences in mean hydraulic conductivity between depths. Hydraulic conductivity measurements ranged up to 3 orders of magnitude within a soil. Variation in hydraulic conductivity estimates, both between and within soil groups, confirmed the variation observed in previous predictions of deep drainage, which were obtained using a semi-empirical model. A cluster analysis on hydraulic conductivity indicated that similar morphological soil properties did not necessarily reflect similar hydrologic properties. There was a strong relationship between hydraulic conductivity and exchangeable sodium percentage (ESP), hydraulic conductivity and clay content, and ESP and clay content. A model was developed to predict field saturated hydraulic conductivity from ESP and clay content data. Hydraulic conductivity measured in this study may not have been representative of percolation rates which would occur with low salinity irrigation water, but can be used to assess the risk of recharge from irrigation on different soils in the lower Macquarie Valley. Shallow watertables may potentially develop when the application of irrigation water greatly exceeds crop water requirements. Quantification of groundwater recharge will allow the likelihood of shallow watertable development in the Lower Macquarie Valley to be assessed.

Effect of saline irrigation on the biomass yield, and the protein, nitrogen, phosphorus, and potassium composition of alfalfa in a pot experiment

Abstract Effect of saline irrigation was studied on the germination, biomass yield, protein content, and nitrogen (N), phosphorus (P), potassium (K) composition of three alfalfa (Medicago sativa) cultivars in a pot experiment. The percent germination of alfalfa cultivars decreased to 15% (Hassawi), 13% (Supreme), and 30% (CUF‐101) receiving irrigation water having total salinity of 12.3 dS/m; and up to to 30% (Hassawi), 22% (Supreme), and 64% (CUF‐101) with irrigation water salinity of 16.5 dS/m. The mortality of young alfalfa seedlings was 100% after two weeks of germination with irrigation water salinity of 12 dS/m and above. The mean green‐matter yield was 56.72 g (Hassawi), 54.29 g (Supreme), and 59.91 g (CUF‐101) per pot irrigated with water having total salinity of 7.8 dS/m. The difference in yield was not significant among the three cultivars. Overall, a green‐matter yield of 11–12 tons/ha per cutting (equivalent to 2.69–3.14 tons/ha dry matter per cutting) could be obtained with irrigation water having an EC of 7.8 dS/m. There was no significant difference in the salt tolerant level between the local (Hassawi cultivar) and the imported (Supreme and CUFlOl) alfalfa cultivars tested. The mean protein contents of alfalfa plants were 22.58% (Hassawi), 29.10% (Supreme), and 23.09% (CUF‐101) irrigated with water having total salinity of 7.8 dS/m. The ranges for the mean concentrations of different macro‐elements in alfalfa plants were 2.51 to 3.94% N, 0.22 to 0.44% P, and 1.48 to 3.22% ?. The analyses of regression indicated a strong interaction between N, P, and ? in alfalfa plants. In conclusion, there was no significant difference in biomass yield, salt‐tolerant level, and the protein contents between local and the imported alfalfa cultivare irrigated with water having salinity of 7.8 dS/m. An appreciable alfalfa green forage yield of 11–12 tons/ha per cutting could be obtained under moderate saline water irrigation.

Strata-bound copper sulfide and nonstrata-bound arsenopyrite and base metal mineralization in the Caledonides of East Greenland; a review

In the central East Greenland Caledonides there are numerous occurrences of strata-bound copper mineralization and hydrothermal arsenic and tungsten mineralization. The host rocks are metasediments of middle Proterozoic and unmetamorphosed to slightly metamorphosed late Proterozoic sediments (quartzite, shale, limestone), all intruded by Caledonian granites.Strata-bound copper mineralization 0.2 to 2 m thick is found at different stratigraphic levels in late Proterozoic shale and quartzite and extends over a distance of 275 km. The mineral assemblages in the shale are dominated by chalcopyrite-pyrite, bornite-chalcocite, or chalcocite. The sulfide associations in the quartzite are chalcopyrite-pyrite-(pyrrhotite) or chalcopyrite-pyrite-(tetrahedrite). In addition strata-bound sulfide-bearing veins occur. The grade of the mineralized zones varies from 0.05 to 1.35 percent Cu. The strata-bound copper sulfides were probably concentrated mainly by diagenetic processes but later were modified by metamorphic mobilization and locally enriched by hydrothermal solutions.Hydrothermal scheelite and arsenopyrite mineralization is located mainly close to the border zone between the Central Metamorphic Complex and the late Proterozoic sediments.Three main types of scheelite mineralization occur: (1) a skarn type, (2) a vein type, and (3) a breccia type. The skarn type is hosted by marble, schist, and calc-silicate rocks. The tungsten content varies from 0.1 to 1 percent W with enrichment of the elements Be, Bi, F, Li, and Sn. Scheelite mineralization in quartz veins yields 0.1 percent W associated with enhanced contents of As, Be, Bi, F, Li, Pb, and Sn. The skarn and vein types are closely related to Caledonian granitic intrusions. The scheelite (+ or -stibnite) mineralized breccia type is found in fault zones probably connected with a granite. These occurrences contain 0.8 to 3 percent W and up to 2.4 Sb and represent at the moment the only mineral deposit of potential economic interest in the area.The arsenopyrite mineralization is regionally widespread. Mineralized quartz veins occur in both quartzitic and semipelitic sediments, whereas mineralized fracture zones are restricted to semipelitic quartzite. The arsenopyrite mineralization is often associated with scheelite, galena, pyrrhotite, chalcopyrite, sphalerite, and traces of gold and silver.The distribution of the elements in the scheelite and arsenopyrite mineralization indicates a zonation around the Caledonian granites. In general, elements such as Be, Bi, F, Li, and Sn are concentrated within 1 to 2 km from the contact. At a greater distance, up to 7 km, the metals Bi, Co, Cu, Pb, and Zn are typical. In terms of fluid inclusions in the veins, the homogenization temperatures of boiling CO 2 -bearing water of moderate salinity are from 225 degrees to 260 degrees C with a pressure of approximately 1 kb.

Desalting in Australia : The development of a new process for brackish water

The present status of desalination in Australia, the world's driest continent, is reviewed. The well-established techniques of distillation, electrodialysis and reverse osmosis have been utilized to obtain potable water from underground sources or the sea. In remote areas where mining and tourism are major industries, about 30 plants with capacities of up to 900 m 3/day have been installed. The future application of large scale desalting is likely to be for municipal purposes in more highly populated regions. The emphasis has been on the treatment of water of moderate salinity which may be of surface, underground, sewage or industrial origin. A new ion exchange desalination process is described which has been developed in Australia to upgrade mildly brackish water to potable or industrial standards. Developed jointly by CSIRO and ICI Australia, the process uses “Sirotherm” resins which are regenerated by hot water, in contrast to the conventional regeneration by chemicals. This uses low grade or waste heat, reduces operating costs compared with existing processes and saves adding extra regenerant chemicals to the environment. Operation of a 600 m 3/day plant to remove 80% of the salinity in a 600 ppm municipal supply has recently commenced at a factory site in Adelaide, Australia. A 20 m 3/day pilot plant has successfully demonstrated the removal of salt from reclaimed sewage in Tokyo, Japan, where water reuse is fast becoming mandatory. The resin is now available commercially throughout the world.