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Journal articles on the topic 'Natural salinity'
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1
Nguyen, Trang Cong, Hoa Van Au, Giang Trung Tran, Phuong Thanh Nguyen, and Ut Ngoc Vu. "Phytoplankton community composition variation under natural and prolonged saline intrusion simulations." International Journal of Limnology 58 (2022): 1. http://dx.doi.org/10.1051/limn/2022001.
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This study assessed phytoplankton community composition variation under two discrete salinity intrusion rate experiments. Experiment 1 simulated salinization under short-term, natural tidally induced rates of salinity change typical of the Mekong Delta, Vietnam (0–30‰ in 6 h), while Experiment 2 simulated salinization under a longer, more gradual rate of salinity change (0–30‰ at 5‰ increase per week). Phytoplankton community composition was, overall, more abundant following prolonged salinity change (Experiment 2) than rapid, tidally-induced salinity change (Experiment 1). Under both experimental conditions phytoplankton species number and density varied with changes in salinity, indicating a strong effect of salinity regardless of its rate of change. At the end of the salinity acclimation, Cyanobacteria, Chlorophyta, Euglenophyta and Bacillariophyta were all most abundant at a salinity of 5‰ after a short-term tidally simulated change in salinity, but with a longer, more gradual change in salinity, the abundance of different groups varied with salinity; With a longer, more gradual change in salinity, Chlorophyta was most abundant at 5–10‰ salinity, while Cyanobacteria, Euglenophyta and Bacillariophyta were all most abundant at a salinity of 5‰. The species composition in treatments of less than 10‰ had high similarity with the freshwater environment while treatments of 30‰ (Experiment 1) and 25‰ (Experiment 2) had high similarity with the natural seawater environment. This study demonstrates the utility of mesocosm experiments for understanding phytoplankton community composition variation in natural aquatic ecosystems under rapid and prolonged saline intrusion rates and predicting associated impacts on food webs in natural water bodies and aquaculture systems.
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Maleki Tirabadi, Mohammad Sadegh, Mohammad Ebrahim Banihabib, and Timothy O. Randhir. "SWAT-S: A SWAT-salinity module for watershed-scale modeling of natural salinity." Environmental Modelling & Software 135 (January 2021): 104906. http://dx.doi.org/10.1016/j.envsoft.2020.104906.
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Taherifar, Hossein, Sima Rezvantalab, Fatemeh Bahadori, and Omid Sadrzadeh Khoei. "Treatments of reverse osmosis concentrate using natural zeolites." Journal of Water and Land Development 25, no. 1 (June 1, 2015): 41–46. http://dx.doi.org/10.1515/jwld-2015-0012.
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Abstract The purpose of the current study is to experimentally investigate the reduction of sodium adsorption ratio (SAR) from a concentrated stream of reversed osmosis (RO) using natural zeolites. In order to reduce the salinity of solution, experiments were carried out using zeolites of varying concentration, pretreatment of adsorbents, and the addition of Ethylenediaminetetraacetic acid (EDTA). The results show that both zeolites can be used in an RO brine treatment; however, Rhyolitic tuff is more effective than clinoptilolite for the reduction of water salinity. The experiments show that Rhyolitic tuff decreases salinity of RO concentrate to nearly one – third of the initial value. Statistical analyses show that the effect of zeolite concentration is negligible. Furthermore, the addition of EDTA and pretreatment of zeolite increase the SAR values.
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Santangelo, Jayme M., Reinaldo L. Bozelli, Adriana de M. Rocha, and Francisco de A. Esteves. "Effects of slight salinity increases on Moina micrura (Cladocera) populations: field and laboratory observations." Marine and Freshwater Research 59, no. 9 (2008): 808. http://dx.doi.org/10.1071/mf08026.
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Salinity is a well-recognised factor that shapes population dynamics and community structure through direct and indirect effects. The responses of Moina micrura (Cladocera) to slight salinity increases (up to 6.0) were evaluated through laboratory manipulative experiments and field observations at Cabiúnas lagoon (Rio de Janeiro, Brazil). From the field data, a positive relationship between M. micrura density and salinity was observed, whereas the opposite was found for other co-occurring microcrustaceans. Life-table observations from laboratory experiments showed better performance of individuals exposed to control conditions (no salt addition) and 1.0 and 2.0 of salinity. The difference between field and laboratory results may be explained considering possible direct and indirect effects of salinity on M. micrura populations. Salinity may have direct negative physiological effects in individuals. However, under natural conditions, M. micrura might benefit from reduced invertebrate predation and interspecific competition. This balance between negative and positive effects of salinity is probably more positive under natural conditions, explaining the success of M. micrura in Cabiúnas lagoon under mild salinity conditions. Although salinity negatively affects many species living in freshwater systems, slight increases may be beneficial for some species under natural conditions.
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Hussain, Abdul, and C. Anilkumar. "Impact of soil salinity on growth performance of the plant Syzygium travancoricum Gamble. in their natural habitat - A critically endangered tree species of Southern Western Ghats." Journal of Non Timber Forest Products 22, no. 4 (December 1, 2015): 219–23. http://dx.doi.org/10.54207/bsmps2000-2015-tq08cx.
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Increased rate of soil salinity caused changes in macro and micro nutrients uptake, which may lead to decline in photosynthesis capacity and respiration in the plant Syzgium travancoricum Gamble. is a critically endangered species located in damp forest with marshy land, where high rate of salt accumulation has been happening. An optimum level of salinity (0.05 - 0.07) is inevitable for the proper growth and survivability of this species in their natural habitat and also for natural regeneration. A range of reduction in the number of existing plants of this species can be seen in their natural habitat due to the salinity stress.
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Xie, Ming Xiao, Ting Xu, and Yin Cai. "Numerical Simulation of the Salty Water Intrusion after the Construction of Houshan Reservoir, China." Advanced Materials Research 1010-1012 (August 2014): 1070–74. http://dx.doi.org/10.4028/www.scientific.net/amr.1010-1012.1070.
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The seawater intrusion of the Gou River, China and the impact of Houshan Reservoir are studied using numerical simulations. The results show that the natural seawater intrusion length is 1.66km for Gou River estuary, and once the Houshan reservoir is constructed the intrusion length increases to 1.98km, which is 0.32km longer than the natural condition. At present, the highest salinity at the estuary is around 18‰, and recovers to fresh water environment in 3.0km. After the construction of the reservoir, the salinity value increase to 20‰ at the estuary. To around 2.0km from the estuary, the salinity recovers to the natural condition.
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Lee, Carol Eunmi. "Ion Transporter Gene Families as Physiological Targets of Natural Selection During Salinity Transitions in a Copepod." Physiology 36, no. 6 (November 1, 2021): 335–49. http://dx.doi.org/10.1152/physiol.00009.2021.
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Salinity is a key factor that structures biodiversity on the planet. With anthropogenic change, such as climate change and species invasions, many populations are facing rapid and dramatic changes in salinity throughout the globe. Studies on the copepod Eurytemora affinis species complex have implicated ion transporter gene families as major loci contributing to salinity adaptation during freshwater invasions. Laboratory experiments and population genomic surveys of wild populations have revealed evolutionary shifts in genome-wide gene expression and parallel genomic signatures of natural selection during independent salinity transitions. Our results suggest that balancing selection in the native range and epistatic interactions among specific ion transporter paralogs could contribute to parallel freshwater adaptation. Overall, these studies provide unprecedented insights into evolutionary mechanisms underlying physiological adaptation during rapid salinity change.
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Kılıc, Orhan Mete, Mesut Budak, Elif Gunal, Nurullah Acır, Rares Halbac-Cotoara-Zamfir, Saleh Alfarraj, and Mohammad Javed Ansari. "Soil salinity assessment of a natural pasture using remote sensing techniques in central Anatolia, Turkey." PLOS ONE 17, no. 4 (April 18, 2022): e0266915. http://dx.doi.org/10.1371/journal.pone.0266915.
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Soil salinity is a major land degradation process reducing biological productivity in arid and semi-arid regions. Therefore, its effective monitoring and management is inevitable. Recent developments in remote sensing technology have made it possible to accurately identify and effectively monitor soil salinity. Hence, this study determined salinity levels of surface soils in 2650 ha agricultural and natural pastureland located in an arid region of central Anatolia, Turkey. The relationship between electrical conductivity (EC) values of 145 soil samples and the dataset created using Landsat 5 TM satellite image was investigated. Remote sensing dataset for 23 variables, including visible, near infrared (NIR) and short-wave infrared (SWIR) spectral ranges, salinity, and vegetation indices were created. The highest correlation between EC values and remote sensing dataset was obtained in SWIR1 band (r = -0.43). Linear regression analysis was used to reveal the relationship between six bands and indices selected from the variables with the highest correlations. Coefficient of determination (R2 = 0.19) results indicated that models obtained using satellite image did not provide reliable results in determining soil salinity. Microtopography is the major factor affecting spatial distribution of soil salinity and caused heterogeneous distribution of salts on surface soils. Differences in salt content of soils caused heterogeneous distribution of halophytes and led to spectral complexity. The dark colored slickpots in small-scale depressions are common features of sodic soils, which are responsible for spectral complexity. In addition, low spatial resolution of Landsat 5 TM images is another reason decreasing the reliability of models in determining soil salinity.
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Šlekienė, Violeta, Loreta Ragulienė, and Vincentas Lamanauskas. "NATURAL SCIENCE AND MATHEMATICS INTEGRATION POSSIBILITIES RESEARCHING WATER SALINITY." Natural Science Education in a Comprehensive School (NSECS) 21, no. 1 (April 10, 2015): 60–67. http://dx.doi.org/10.48127/gu/15.21.60.
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Interdisciplinary natural science education relations are developed mostly between biology, chemistry, physics, mathematics and information technologies. The teachers have to convey education content, consisting of separate concepts, laws, theories as a harmonious whole, revealing interrelation between the analysed phenomena. Organising natural science teaching in this way, the teaching material is reorganised, systemised. Solving interdisciplinary integration problems, active communication and cooperation is going on between individual natural science teachers. Seeking to generally and newly look at the natural science teaching and learning process, grounded on interdisciplinary relations, interdisciplinary experiments are carried out. Water salinity research has been chosen, because in this topic analysis, rather wide integration possibilities are discerned. Physics teacher together with the pupils would deepen the knowledge of conductivity, electrolytes, electric current in the electrolytes, chemistry teachers – of electrolytic dissociation, solution concentration, mathematics teachers - would remember percent calculation, linear equation analysis, biology teachers – about water salinity effect on the man and on the environment surrounding him. In the article, lesson organisation and research performance methodics is discussed, the essence of practical work is explained, tasks and examples are presented. Several different subject (physics, chemistry, biology, mathematics) teachers could participate in the lesson, which could form the conditions not in disintegrated way, but systematically convey the pupils the essence of the analysed phenomenon. Key words: education content, interdisciplinary integration, natural science education, science teachers.
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Bolhuis, Henk, Lucas Fillinger, and Lucas J. Stal. "Coastal Microbial Mat Diversity along a Natural Salinity Gradient." PLoS ONE 8, no. 5 (May 21, 2013): e63166. http://dx.doi.org/10.1371/journal.pone.0063166.
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Ali, M. P., M. S. Rahman, Farzana Nowrin, S. S. Haque, Xinghu Qin, M. A. Haque, M. M. Uddin, Douglas A. Landis, and M. T. H. Howlader. "Salinity Influences Plant–Pest–Predator Tritrophic Interactions." Journal of Economic Entomology 114, no. 4 (July 7, 2021): 1470–79. http://dx.doi.org/10.1093/jee/toab133.
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Abstract Climate change-induced salinity intrusion into agricultural soils is known to negatively impact crop production and food security. However, the effects of salinity increase on plant–herbivore–natural enemy systems and repercussions for pest suppression services are largely unknown. Here, we examine the effects of increased salinity on communities of rice (Oryza sativa), brown planthopper (BPH), Nilaparvata lugens, and green mirid bug (GMB), Cyrtorhinus lividipennis, under greenhouse conditions. We found that elevated salinity significantly suppressed the growth of two rice cultivars. Meanwhile, BPH population size also generally decreased due to poor host plant quality induced by elevated salinity. The highest BPH density occurred at 2.0 dS/m salinity and declined thereafter with increasing salinity, irrespective of rice cultivar. The highest population density of GMB also occurred under control conditions and decreased significantly with increasing salinity. Higher salinity directly affected the rice crop by reducing plant quality measured with reference to biomass production and plant height, whereas inducing population developmental asynchrony between BPH and GMB observed at 2 dS/m salinity and potentially uncoupling prey–predator dynamics. Our results suggest that increased salinity has harmful effects on plants, herbivores, natural enemies, as well as plant–pest–predator interactions. The effects measured here suggest that the bottom-up effects of predatory insects on rice pests will likely decline in rice produced in coastal areas where salinity intrusion is common. Our findings indicate that elevated salinity influences tritrophic interactions in rice production landscapes, and further research should address resilient rice insect pest management combining multipests and predators in a changing environment.
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Ludwiczak, Agnieszka, Monika Osiak, Stefany Cárdenas-Pérez, Sandra Lubińska-Mielińska, and Agnieszka Piernik. "Osmotic Stress or Ionic Composition: Which Affects the Early Growth of Crop Species More?" Agronomy 11, no. 3 (February 27, 2021): 435. http://dx.doi.org/10.3390/agronomy11030435.
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Salinization is a key soil degradation process. An estimated 20% of total cultivated lands and 33% of irrigated agricultural lands worldwide are affected by high salinity. Much research has investigated the influence of salt (mainly NaCl) on plants, but very little is known about how this is related to natural salinity and osmotic stress. Therefore, our study was conducted to determine the osmotic and ionic salt stress responses of selected C3 and C4 cultivated plants. We focused on the early growth stages as those critical for plant development. We applied natural brine to simulate natural salinity and to compare its effect to NaCl solution. We assessed traits related to germination ability, seedlings and plantlet morphology, growth indexes, and biomass and water accumulation. Our results demonstrate that the effects of salinity on growth are strongest among plantlets. Salinity most affected water absorption in C3 plants (28% of total traits variation), but plant length in C4 plants (17–27%). Compensatory effect of ions from brine were suggested by the higher model plants’ growth success of ca 5–7% under brine compared to the NaCl condition. However, trait differences indicated that osmotic stress was the main stress factor affecting the studied plants.
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BARNARD, A., M. D. MAX, and L. GUALDESI. "Submarine vortices derived from natural gas hydrate conversion: a mechanism for ocean mixing." Mediterranean Marine Science 18, no. 2 (August 1, 2017): 202. http://dx.doi.org/10.12681/mms.1640.
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We propose that the source water for some abyssal undular vortices cored by cool, low-salinity water identified at depths in excess of 2,500 m in the deepwater region of the Eastern Mediterranean Basin may be related to conversion of natural gas hydrate (NGH) in abyssal marine sediments. The conditions for extensive formation of NGH in the gas hydrate stability zones (GHSZ) of the upper seafloor sediments existed in this region during previous glacial episodes when colder water supported a thicker GHSZ. Seafloor warming during the most recent interglacial caused thinning of the GHSZ at its base and has driven endothermic NGH dissociation that would have released large volumes of low-salinity water and gas that would tend to pond below the base GHSZ. Periodically, trapped low-salinity water and gas would be released into the sea through the overlying sediments. Buoyant low-salinity water masses, supersaturated with gas and locally containing free gas would ascend and introduce a dynamic element into an otherwise generally static environment. As a result of the interaction of the rise of this buoyant plume and Coriolis acceleration the ascending mass would begin to rotate and form a vortex tube in midwater. NGH conversion within the seafloor introduces large coherent masses of low-salinity, lower-temperature water containing a buoyant free gas fraction from near-surface reservoirs into the abyssal depths even where there may only be a weak natural gas petroleum system.
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P, Raveesha, K. E. Prakash, and B. T. Suresh Babu. "Investigational Studies on Quantity of Salinity in Netravati River Estuary Sand-Coastal Karnataka." International Journal of Emerging Research in Management and Technology 6, no. 6 (June 29, 2018): 46. http://dx.doi.org/10.23956/ijermt.v6i6.243.
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The salt water mixes with fresh water and forms brackish water. The brackish water contains some quantity of salt, but not equal to sea water. Salinity determines the geographic distribution of the number of marshes found in estuary. Hence salinity is a very important environmental factor in estuary system. Sand is one major natural aggregate, required in construction industry mainly for the manufacture of concrete. The availability of good river sand is reduced due to salinity. The quality of sand available from estuarine regions is adversely affected due to this reason. It is the responsibility of engineers to check the quality of sand and its strength parameters before using it for any construction purpose. Presence of salt content in natural aggregates or manufactured aggregates is the cause for corrosion in steel. In this study the amount of salinity present in estuary sand was determined. Three different methods were used to determine the salinity in different seasonal variations. The sand sample collected nearer to the sea was found to be high in salinity in all methods. It can be concluded that care should be taken before we use estuary sand as a construction material due to the presence of salinity.
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Ubaskin, A. V., K. I. Akhmetov, A. I. Lunkov, N. T. Yerzhanov, T. Zh Abylkhassanov, and A. U. Abylkhassanova. "EXPERIMENTAL RESEARCH FOR TECHNOLOGICAL PREPARATION OF ARTEMIA (ARTEMIA) ARTIFICIAL CULTIVATION IN SALT LAKES." Series of biological and medical 2, no. 338 (April 15, 2020): 69–73. http://dx.doi.org/10.32014/10.32014/2020.2519-1629.15.
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An integral part of the technological preparation of artificial cultivation of brine shrimp in saline water is a set of preliminary experimental work to assess the quality of cysts. It has been shown that during the winter period, activation of Artemia cysts occurs from the initial hatching values of 5-10 % to 72-99 %. The most optimal salinity range for hatching nauplii is a salinity of 20-30 g/l. With an increase in salinity above these indicators, hatching decreases. The size of hatching of Artemia depends on the salinity of a natural reservoir. In reservoirs with salinity of 50-80 g / l, higher hatching rates were obtained than with salinity of 150-160 g/l. Higher hatching rates are observed when using natural lake water for incubation. During incubation of cysts in a standard solution and fixed salinity and temperature conditions, the development rate of various stages of nauplii from the beginning of the opening of cysts (breaking stage) and pre-nauplius to active nauplii is shown. After 1.5–2 h after the mass appearance of pre-nauplii, they completely change into the nauplius stage.
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Ereim, Sama Faisal Abdulsattar Abdulrazzaq, and Sadoon Dhahir Khalaf Al-Dulaimy. "Natural Problems Face Agricultural Industry in The Countryside of Heet District." Journal of AlMaarif University College 33, no. 4 (December 7, 2022): 412–34. http://dx.doi.org/10.51345/.v33i4.603.g318.
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The study area suffers from a number of natural problems that affect agricultural production, the most important of which are the problems related to climate, soil erosion, the problem of agricultural pests and diseases, jungles, the problem of water and the problem of soil salinity. Its impact on agricultural production, one of the problems that is difficult to control is the problem of extreme climate, as it clearly affects crops, especially with the decline of the idea of protected agriculture, which provides suitable weather for plants. As for erosion, it leads to a significant decrease in soil fertility, as well as pollution of the river and air. It was necessary to address this problem by providing vegetation cover and intensifying agriculture. As for pests, we have noticed the spread of many types of agricultural pests that have had a very clear impact on agricultural production, especially with the absence of means to combat them and the farmers’ ignorance of how to combat each type. As for the jungle, it is a problem with known causes, but it needs solutions, including combating the jungle before planting and purifying the seeds before planting, and one of the natural problems affecting agricultural production is the water problem. Drought, as for the problem of salinity, random watering by immersion, high temperatures, salinity of the water itself, and the disappearance of drains are all factors that exacerbated the problem of salinity.
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Mkilima, Timoth, Davud Devrishov, Kydyrbekova Assel, Nurbala Ubaidulayeva, Almas Tleukulov, Alissa Khassenova, Nargiza Yussupova, and Dinara Birimzhanova. "Natural Zeolite for The Purification of Saline Groundwater and Irrigation Potential Analysis." Molecules 27, no. 22 (November 10, 2022): 7729. http://dx.doi.org/10.3390/molecules27227729.
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Groundwater is one of the main sources of water for irrigation used worldwide. However, the application of the resource is threatened by the possibility of high saline levels, especially in low-lying coastal regions. Furthermore, the lack of readily accessible materials for successful treatment procedures makes the purification of such water a constant challenge. Based on the fact that natural zeolite is one of the easily accessible and relatively cheap filter materials, this study examined the potential use of high-salinity groundwater filtered by natural zeolite for irrigation. Zeolite-filled filters at two different depths (0.5 m and 1 m) were studied. The samples were collected from the low-lying areas of Dar es Salaam City, Tanzania. The study observed that when the raw groundwater samples were exposed to the 0.5 m column depth, sodium (Na+) had the lowest removal efficiency at 40.2% and calcium (Ca2+) had the highest removal efficiency at 98.9%. On the other hand, magnesium (Mg2+) had the lowest removal efficiency, at about 61.2%, whereas potassium (K+) had up to about 99.7% removal efficiency from the 1 m column depth treatment system. Additionally, from the salinity hazard potential analysis, most of the samples fell within C4 (based on the electrical conductivity), which is a “very high salinity” class, and based on the quality it means the water cannot be directly applied for irrigation purposes. From the 0.5 m column depth, most of the samples fell within C3 (the “high salinity” class), and from the 1 m column depth most of the samples fell within C1 (“low salinity” class). The findings of this study offer some valuable insight into the prospective use of natural zeolite for the filtration of saline groundwater before its application for irrigation.
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Sui, Na, Yu Liu, and Bao Shan Wang. "Comparative Study on Photosynthetic Characteristics of Two Ecotypes of Euhalophyte Suaeda salsa L. Grown Under Natural Saline Conditions." Advanced Materials Research 726-731 (August 2013): 4488–93. http://dx.doi.org/10.4028/www.scientific.net/amr.726-731.4488.
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Suaeda salsa L. grown in the intertidal zone and those in high salinity soils of the Yellow River Delta were used to investigate the category and characteristic of photosynthesis and fluorescence. Results showed that the water content, Na+ and Cl- contents of the high salinity soils were lower. The temperature on the surface of soil and in the depth of 10 cm from the surface, the content of K+ and Ca2+ of the high salinity soils were significantly higher than those in the intertidal zone soils. Pn, Gs, Fv/Fm, ФPSII, the fresh weight and dry weight per plant of S. salsa grown in the high salinity soils were higher. However, Ci of S. salsa grown in the high salinity soils were lower. These suggested that S. salsa grown in the high salinity soils was mainly suffering from salt stress, while S. salsa in the intertidal zone soils was suffering from waterlogging, low temperature and salt stress together. S. salsa in the intertidal zone soils decreased light absorption and alleviated photoinhibition, but as a result the biomass was reduced.
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Abdrashitov, Rimma N., and Marsel A. Kadyrov. "Causes of Variability in Groundwater Salinity of the Lower Jurassic Sediments in the Talinskoye Oilfield of West Siberia." Sustainability 14, no. 13 (June 23, 2022): 7675. http://dx.doi.org/10.3390/su14137675.
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This study aimed to identify the nature of variable groundwater salinity from the standpoint of whether natural or man-caused factors have a dominant impact on the modern salinity range of the Lower Jurassic sediments in the Talinskoye oilfield of West Siberia in Russia. As of now, the salinity values of reservoir waters vary from 3.7 to 15.3 g/dm3, with an average of 8.9 g/dm3. Petroleum hydrocarbons are extracted at the oilfield from the Lower Jurassic sediments. The volume of overlying sediments’ waters injected into the pay zones to maintain the formation pressure was more than 8960.3 thousand m3 between 2014 and 2021. In this regard, it is necessary to establish whether anthropogenic factors are critical for the variability in groundwater salinity of the Lower Jurassic sediments, or the complex geologic and hydrogeologic conditions are determinant factors affecting the salinity variability. To achieve this objective, we evaluated the genetic coefficients of various types of waters (inclusive of injected waters) which could contribute to the variability in groundwaters with varying quantities and ratios. The resultant genetic coefficients were compared with those of reservoir waters of the Lower Jurassic hydrogeological complex. This allowed for the conclusion that the major factors currently affecting the variable salinity of the reservoir waters of the Lower Jurassic complex are natural ones. We also assessed the relationship between the groundwater salinity values of the complex under study and basic parameters of the geologic setting, such as porosity, formation pressure, modern temperature and paleotemperature of the basement, and basement depth of burial. A tight association was found between the salinity values and porosity of the sediments (R = 0.87), and a very tight connection between the salinity and formation pressure (R = 0.91), which, we believe, also evidences that natural factors have a dominant effect on the variability in groundwater salinity. The variability in the modern salinity values of the reservoir waters of the complex in question ensues from the continental conditions of the groundwater genesis, expelled-water exchange processes (ingress of the pore waters expelled from argillaceous deposits as geostatic pressure rises), and the intrusion of abyssal fluids along the basement fractures.
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Nielsen, D. L., M. A. Brock, G. N. Rees, and D. S. Baldwin. "Effects of increasing salinity on freshwater ecosystems in Australia." Australian Journal of Botany 51, no. 6 (2003): 655. http://dx.doi.org/10.1071/bt02115.
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Salt is a natural component of the Australian landscape to which a number of biota inhabiting rivers and wetlands are adapted. Under natural flow conditions periods of low flow have resulted in the concentration of salts in wetlands and riverine pools. The organisms of these systems survive these salinities by tolerance or avoidance. Freshwater ecosystems in Australia are now becoming increasingly threatened by salinity because of rising saline groundwater and modification of the water regime reducing the frequency of high-flow (flushing) events, resulting in an accumulation of salt. Available data suggest that aquatic biota will be adversely affected as salinity exceeds 1000 mg L–1 (1500 EC) but there is limited information on how increasing salinity will affect the various life stages of the biota. Salinisation can lead to changes in the physical environment that will affect ecosystem processes. However, we know little about how salinity interacts with the way nutrients and carbon are processed within an ecosystem. This paper updates the knowledge base on how salinity affects the physical and biotic components of aquatic ecosystems and explores the needs for information on how structure and function of aquatic ecosystems change with increasing salinity.
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Skipin, Leonid, Elena Gaevaya, and Svetlana Tarasova. "The reaction of seeds of phytomeliorant crops under the condition of natural and technogenic salinization of soils and soils." Agrarian Bulletin of the 231, no. 02 (March 27, 2023): 30–40. http://dx.doi.org/10.32417/1997-4868-2023-231-02-30-40.
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Abstract. The purpose of the study is to establish the optimal and critical values of different chemisms and the degree of salinity and the corresponding indicators of osmotic pressure, pH of the medium for the germination energy and germination of seeds of alfalfa and sweet clover. Objectives of the study are to identify the parameters of 50 and 99 % death of seeds of the studied crops, taking into account the chemistry and degree of salinity, to determine the most toxic water-soluble salts in solonetzic soils and drill cuttings; to identify the degree of participation of osmotic pressure and pH of the medium for the studied options, to conduct a comparative study of chemisms and the degree of their salinity on the germination and germination of seeds of phytomeliorants. Methods. The experiments were carried out in laboratory conditions. Seeds of sweet clover of the Alsheevskiy variety and alfalfa of the Yaroslavna variety were used as the object of the study. The energy and germination of seeds were determined according to GOST 12038-84. Scientific novelty. For the first time, the parameters the average lethal dose and the dose is absolutely lethal for sweet clover and alfalfa seeds were established in relation to different salinity chemisms, represented by one easily soluble salt, identical to soil and technogenic salinization. The parameters of osmotic pressure and pH of the medium for the average lethal dose and the dose is absolutely lethal were determined for each salinity chemistry. Results. It was found that a low concentration of MgSO4 (up to 0.3 %) did not reduce the energy and germination of seeds of sweet clover and alfalfa. Sodium neutral salts (Na2SO4, NaCl) led to the loss of seed germination of sweet clover and alfalfa (the dose is absolutely lethal) at a salinity degree of 2.0–2.9 %, which corresponds to a high osmotic pressure of 8.9–13.9 atm. Sweet clover seeds had a higher capacity for maximum salinity. Under soda salinity (Na2CO3, NaHCO3), 50 % death of sweet clover and alfalfa seeds corresponded to salinity levels of solonetzes and drill cuttings of 0.09 and 0.25 %. The phenomenon corresponding to the dose is absolutely lethal was noted here, respectively, at the level of salinity of soils and drill cuttings of 0.42 and 0.95 %. It is important to take into account the average lethal dose indicator when recultivating solonetzes and drill cuttings in order to establish seeding rates and select phytomeliorant crops.
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Kirkpatrick, A. T., R. F. Gordon, and D. H. Johnson. "Double Diffusive Natural Convection in Solar Ponds With Nonlinear Temperature and Salinity Profiles." Journal of Solar Energy Engineering 108, no. 3 (August 1, 1986): 214–18. http://dx.doi.org/10.1115/1.3268095.
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A solar pond can be used as a thermal energy source provided that convective instabilities do not occur. This paper experimentally examines the stability of a fluid layer with nonlinear salinity and temperature profiles. A nonlinear salt profile was set up in a fluid layer, and the water was heated by a solar radiation simulator. Three stability experiments were conducted. Instabilities occurred at the location of the weakest salinity gradient, and were confined to a thin region, as predicted by theory. A local length scale was used to produce a stability parameter, the ratio of thermal to solute Rayleigh numbers. It is shown that for nonconstant solute and temperature gradients, the appropriate length scale is based on the radius of curvature of the salinity distribution. With this chocie of a length scale, good agreement was found between theory and experiment for the onset of an instability.
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Kaartokallio, Hermanni, Maria Laamanen, and Kaarina Sivonen. "Responses of Baltic Sea Ice and Open-Water Natural Bacterial Communities to Salinity Change." Applied and Environmental Microbiology 71, no. 8 (August 2005): 4364–71. http://dx.doi.org/10.1128/aem.71.8.4364-4371.2005.
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ABSTRACT To investigate the responses of Baltic Sea wintertime bacterial communities to changing salinity (5 to 26 practical salinity units), an experimental study was conducted. Bacterial communities of Baltic seawater and sea ice from a coastal site in southwest Finland were used in two batch culture experiments run for 17 or 18 days at 0°C. Bacterial abundance, cell volume, and leucine and thymidine incorporation were measured during the experiments. The bacterial community structure was assessed using denaturing gradient gel electrophoresis (DGGE) of PCR-amplified partial 16S rRNA genes with sequencing of DGGE bands from initial communities and communities of day 10 or 13 of the experiment. The sea ice-derived bacterial community was metabolically more active than the open-water community at the start of the experiment. Ice-derived bacterial communities were able to adapt to salinity change with smaller effects on physiology and community structure, whereas in the open-water bacterial communities, the bacterial cell volume evolution, bacterial abundance, and community structure responses indicated the presence of salinity stress. The closest relatives for all eight partial 16S rRNA gene sequences obtained were either organisms found in polar sea ice and other cold habitats or those found in summertime Baltic seawater. All sequences except one were associated with the α- and γ-proteobacteria or the Cytophaga-Flavobacterium-Bacteroides group. The overall physiological and community structure responses were parallel in ice-derived and open-water bacterial assemblages, which points to a linkage between community structure and physiology. These results support previous assumptions of the role of salinity fluctuation as a major selective factor shaping the sea ice bacterial community structure.
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Fakharian, Hajar, Hamid Ganji, and Abbas Naderifar. "Desalination of high salinity produced water using natural gas hydrate." Journal of the Taiwan Institute of Chemical Engineers 72 (March 2017): 157–62. http://dx.doi.org/10.1016/j.jtice.2017.01.025.
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Smolyanyuk, E. V., and E. N. Bilanenko. "Communities of halotolerant micromycetes from the areas of natural salinity." Microbiology 80, no. 6 (December 2011): 877–83. http://dx.doi.org/10.1134/s002626171106021x.
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Bi, Pan, Dongya Han, Chunyan Liu, Liquan Xiao, Heqiu Wu, and Meng Zhang. "Natural Background Level and Contamination of Shallow Groundwater Salinity in Various Aquifers in a Coastal Urbanized Area, South China." Journal of Chemistry 2021 (August 6, 2021): 1–9. http://dx.doi.org/10.1155/2021/2973092.
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Assessing natural background levels (NBLs) of chemical components in groundwater is useful for the evaluation of groundwater contamination in urbanized areas. The present study assessed the NBL of total dissolved solids (TDS) in various groundwater units in the Pearl River Delta (PRD) where urbanization is a large scale and discussed factors controlling groundwater salinity contamination in the PRD. Results showed that the NBL of TDS in groundwater in the coastal-alluvial plain was more than 1.5 times that in other groundwater units because of the seawater intrusion in this groundwater unit. By contrast, interactions of water and soils/rocks were the main factors controlling the NBLs of TDS in other groundwater units. Groundwater salinity contamination in the PRD was positively correlated with the urbanization level. Wastewater from township-village enterprises and industrial wastewater were likely to be the main sources for groundwater salinity contamination in the PRD. Moreover, the wastewater leakage from sewer systems was one of the main pathways for groundwater salinity contamination in urbanized areas, because the proportion of groundwater salinity contamination in urbanized areas formed in 1988–1998 was more than 1.5 times that in urbanized areas formed in 1998–2006 regardless of groundwater units. Besides, sewage irrigation and leakage of landfill leachate were also important sources for groundwater salinity contamination in the PRD.
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WONG, HIN-CHUNG, and SHU-HUI LIU. "Susceptibility of the Heat-, Acid-, and Bile-Adapted Vibrio vulnificus to Lethal Low-Salinity Stress." Journal of Food Protection 69, no. 12 (December 1, 2006): 2924–28. http://dx.doi.org/10.4315/0362-028x-69.12.2924.
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As a marine pathogenic bacterium that inhabits seawater or seafood, Vibrio vulnificus encounters low salinity and other stresses in the natural environment and during food processing. This investigation explores the cross-protective response of sublethal heat-, acid-, or bile-adapted V. vulnificus YJ03 against lethal low-salinity stress. Experimental results reveal that the acid (pH 4.4)– and heat (41°C)–adapted V. vulnificus were not cross-protected against the lethal low-salinity challenge (0.04% NaCl). The bile (0.05%)–adapted exponential- and stationary-phase cells were cross-protected against low salinity, whereas low-salinity (0.12% NaCl)–adapted stationary cells were sensitized against 12% bile stress. Results of this study provide further insight into the interaction between low salinity and other common stresses in V. vulnificus.
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Litvinenko, L., A. Litvinenko, E. Boyko, M. Korentovich, and P. Zenkovich. "Experimental studies to increase the natural resources of brine shrimp Artemia in hyperhaline reservoirs." IOP Conference Series: Earth and Environmental Science 937, no. 2 (December 1, 2021): 022073. http://dx.doi.org/10.1088/1755-1315/937/2/022073.
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Abstract A brief analysis of the available technologies for growing Artemia in the world and in Russia is given in the paper. The conditions for production of Artemia in natural reservoirs with a local Artemia population are shown. The results of laboratory experiments on reducing the incubation time of cysts to 2-23 hours (instead of the standard 24-48 hours) and the inoculation of nauplii and non-hatched cysts into the brine of natural lakes with salinity of 101, 125, 225 and 333‰ are given in details. The following indicators are analyzed: the rate of hatching during incubation, the rate of hydration of cysts during incubation and dehydration in brine; the survival rate of nauplii in brine, the possibility of hatching nauplii from cysts in brine with different salinity. The results of long-term observations of the survival of Artemia crustaceans in the brine of the lake in the absence of feeding are also presented. It is possible to reduce the incubation time to 6-20 hours is concluded in the paper. The dependence of the duration of incubation of cysts on the temperature, quality of cysts and salinity of natural brine was noted. To determine the optimal incubation time of cysts the formulas for calculating T90 according to the temperature and salinity of brine for cysts of different quality are given.
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Gaston, Gary R., Chet F. Rakocinski, Steven S. Brown, and Carol M. Cleveland. "Trophic function in estuaries: response of macrobenthos to natural and contaminant gradients." Marine and Freshwater Research 49, no. 8 (1998): 833. http://dx.doi.org/10.1071/mf97089.
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Trophic ecology of macrobenthic communities in estuaries of the northern Gulf of Mexico was used to infer community function, determine effects of contaminants on macrobenthos, and provide insight into community responses following disturbance. The taxa that numerically dominated the region included few large, deep-burrowing suspension feeders that typify estuaries elsewhere. This pattern is indicative of disturbance, and results in dominance by trophic groups that live near the sediment–water interface (early benthic-community succession). Trophic structure was significantly related to several sediment contaminants (especially metals, polynuclear aromatic hydrocarbons, DDT), and three environmental gradients (salinity, depth, and sediment silt–clay content). Generally, trophic diversity increased and proportion of subsurface-deposit feeders (SSDF) decreased with salinity, meaning that a more even distribution of trophic structure was found at high-salinity stations. The trophic shift toward dominance by shallow, subsurface-deposit feeders in contaminated habitats may have dire implications for fisheries. Several important commercial and recreational fisheries of the region depend on fish that feed primarily at the sediment surface. Higher proportion of subsurface-deposit feeders, coupled with low macrobenthic density in contaminated sediments, may imply that limited energy is transferred to higher trophic levels.
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Pavloudi, Christina, Jon B. Kristoffersen, Anastasis Oulas, Marleen De Troch, and Christos Arvanitidis. "Sediment microbial taxonomic and functional diversity in a natural salinity gradient challenge Remane’s “species minimum” concept." PeerJ 5 (October 13, 2017): e3687. http://dx.doi.org/10.7717/peerj.3687.
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Several models have been developed for the description of diversity in estuaries and other brackish habitats, with the most recognized being Remane’s Artenminimum (“species minimum”) concept. It was developed for the Baltic Sea, one of the world’s largest semi-enclosed brackish water body with a unique permanent salinity gradient, and it argues that taxonomic diversity of macrobenthic organisms is lowest within the horohalinicum (5 to 8 psu). The aim of the present study was to investigate the relationship between salinity and sediment microbial diversity at a freshwater-marine transect in Amvrakikos Gulf (Ionian Sea, Western Greece) and assess whether species composition and community function follow a generalized concept such as Remane’s. DNA was extracted from sediment samples from six stations along the aforementioned transect and sequenced for the 16S rRNA gene using high-throughput sequencing. The metabolic functions of the OTUs were predicted and the most abundant metabolic pathways were extracted. Key abiotic variables, i.e., salinity, temperature, chlorophyll-a and oxygen concentration etc., were measured and their relation with diversity and functional patterns was explored. Microbial communities were found to differ in the three habitats examined (river, lagoon and sea) with certain taxonomic groups being more abundant in the freshwater and less in the marine environment, andvice versa. Salinity was the environmental factor with the highest correlation to the microbial community pattern, while oxygen concentration was highly correlated to the metabolic functional pattern. The total number of OTUs showed a negative relationship with increasing salinity, thus the sediment microbial OTUs in this study area do not follow Remane’s concept.
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Abdullaev, Ilkhomjon, Abdumanap Nasirov, Gayrat Yakubov, and Nargiza Abdullaeva. "Application of GIS technologies in the investigation of soil salinity." E3S Web of Conferences 386 (2023): 01009. http://dx.doi.org/10.1051/e3sconf/202338601009.
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Soil salinization is the major problem affecting the productivity of irrigated lands. In Uzbekistan, irrigated area amounts to 4.5 million hectares or about 10% of Uzbekistan’s total area and almost 46.6% of these lands are affected by increasing salinity. The main reason for these conditions of irrigated land is the effect caused by natural factors (primary salinity) - inefficient natural drainage, saline groundwater, high evapotranspiration rates, and high capillary capacity of the soil. Moreover, human-induced processes (so-called “secondary salinity”), which lead to the enrichment of mineralization of groundwater. The objectives of this study iarethe soil salinity monitoring of irrigated lands and the mapping of the temporal and spatial distribution of salt-affected soils for the Arnasay district of Jizzakh province in Uzbekistan to support land management. Field data collected in 2017- 2018 was analyzed and based on the analysis soil map was developed. In the research area, based on these maps changes in soil salinity were identified. The results indicate that inefficient irrigation activities in the region would affect to the enrichment of salts in the top soils and reduce soil productivity. The GIS technologies are efficient tools for monitoring salt-affected lands.
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Lefebvre, Guy, Karol Rohan, and Jean-Pierre Milette. "Erosivity of intact clay: Influence of the natural structure." Canadian Geotechnical Journal 23, no. 4 (November 1, 1986): 427–34. http://dx.doi.org/10.1139/t86-072.
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Erodibility drill hole tests have been conducted on three Eastern Canadian clays on intact structured specimens, on specimens destructured by consolidation, and on remolded and reconsolidated specimens. The intact structured clay is highly resistant to erosion; links between particles can resist high tractive stresses. The resistance to erosion is drastically decreased however when the clay is destructured by consolidation or remolding. The decrease varies from one clay to the other; after consolidation the resistance to erosion is very low for the St. Hyacinthe clay but still high for the St. Leon clay. The clays are even more erodible after remolding and reconsolidation, but important differences are still observed between the clays tested. The pore water salinity appears as a significant factor in the understanding of the different behaviour observed after destructuration of the clay by consolidation or remolding. Key words: erosivity, rate of erosion, critical tractive stress, structured clay, destructuration, consolidation, remolding, pore water salinity.
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Dekov, Vesselin, Veerle Van Alsenoy, Nur Onar, Annick Van Put, and René Van Grieken. "Partitioning of heavy metals between estuarine sediments and dissolved phase as a function of salinity, pH and time (Scheldt estuary)." Geologica Balcanica 30, no. 3-4 (February 28, 2001): 65–76. http://dx.doi.org/10.52321/geolbalc.30.3-4.65.
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The distribution coefficient (Kd) and kinetics of the heavy metals Cd, Cu, Zn and Pd as a function of salinity and pH are investigated experimentally considering desorption processes and adsorption of 109Cd radiotracer for natural particulate matter from the Scheldt estuary (Belgium/The Nitherlands). The desorption of Cu from polluted estuarine sediments is very low. Only at high salinities minor desorption was detected. At persistently low pH (<4), desorption was completed to 100 %. Also the Pb desorption is very limited and only strong acidification of the solution will efficiently desorb a considerable fraction of the element. The desorption of Cd is significant as a function of all the considered parameters. The desorption process is fast and up to 60 % of the adsorbed Cd can be released into natural water. Both the salinity and the pH can change the distribution between the solid and the dissolved phase significantly. The extent of Zn desorption is intermediate between Cd and Pb. Both salinity and pH are important parameters to be considered for the sorption processes in the natural environment. The adsorption of 109Cd on natural particulate matter from the Scheldt estuary changes as a function of temperature, salinity and composition of the particulate matter. The temperature has only a minor influence on the Kd-salinity relation, while the composition of the suspended matter showed to be very important. Even though the number of samples used was small, preliminary results show that organic content of sediments may be the most important parameter for adsorption of Cd. A similar relation between the Kd of the adsorption process using 109Cd and the desorption process as a function of salinity, indicates that the metal binding character of the adsorbed 109Cd may be identical to that of the naturally bound Cd released during the desorption process. The magnitude of the Kd, however, needs to be determined according to the different environmental parameters.
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Kalske, Aino, Kari Saikkonen, and Marjo Helander. "Endophytic Fungus Negatively Affects Salt Tolerance of Tall Fescue." Journal of Fungi 9, no. 1 (December 21, 2022): 14. http://dx.doi.org/10.3390/jof9010014.
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Vertically transmitted endophytic fungi can mitigate the negative effects of salinity encountered by their host grass and alter the competitive interactions between plant individuals. To experimentally study the interactive effects of the fungal endophyte Epichloë coenophiala on salt tolerance and intraspecific competition of its host plant, tall fescue Festuca arundinacea, we subjected 15 maternal lines of each Epichloë associated (E+) and Epichloë free (E-) tall fescue to salt treatment and competition in the greenhouse and common garden. Then, to explore variation in endophyte incidence in natural populations of tall fescue, we surveyed 23 natural populations occurring on or near the Baltic Sea coast in Aland islands in southwestern Finland for endophyte incidence, distance to shore, and competitive environment. Under salinity in the greenhouse, E- plants grew larger than E+ plants, but there was no size difference in the control treatment. E- plants grew taller and were more likely to flower than E+ plants when grown in benign conditions in the common garden but not with salinity or competition. The frequency of Epichloë incidence was high (90%) in natural populations, and it decreased towards the shore and risk of salt exposure. These results demonstrate a negative effect of Epichloë endophyte on the salt tolerance of its host. The high incidence of Epichloë in natural populations of tall fescue in the northern part of the species distribution range is likely due to factors other than salinity.
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Zhou, K., S. D. Nodder, M. Dai, and J. A. Hall. "Insignificant enhancement of export flux in the highly productive subtropical front, east of New Zealand: a high resolution study of particle export fluxes based on <sup>234</sup>Th: <sup>238</sup>U disequilibria." Biogeosciences 9, no. 3 (March 12, 2012): 973–92. http://dx.doi.org/10.5194/bg-9-973-2012.
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Abstract. We evaluated the export fluxes of Particulate Organic Carbon (POC) in the Subtropical Frontal zone (STF) of the SW Pacific sector of the Southern Ocean. The site is characterized by enhanced primary productivity, which has been suggested to be stimulated through so-called natural iron fertilization processes where iron-depleted subantarctic water (SAW) mixes with mesotrophic, iron-replete subtropical water (STW). We adopted the small-volume 234Th method to achieve the highest possible spatial sampling resolution in austral late autumn-early winter, May–June, 2008. Inventories of chlorophyll-a, particulate 234Th and POC observed in the upper 100 m were all elevated in the mid-salinity water type (34.5 < S < 34.8), compared with low salinity waters (S < 34.5) which were of SAW origin with high macronutrients and high (S > 34.8) salinity waters which were of STW origin with low macronutrients. However, Steady-State 234Th fluxes were similar across the salinity gradient being, 25 ± 0.78 ((1.5 ± 0.047) × 103) in the mid-salinity, and 29 ± 0.53 ((1.8 ± 0.032) × 103) and 22 ± 1.1 Bq m−2 d−1 ((1.3 ± 0.066) × 103 dpm m−2 d–1) in the high and low salinity waters respectively. Bottle POC/Th ratios at the depth of 100 m were used to convert 234Th fluxes into POC export fluxes. The derived POC flux did not appear to be enhanced in mid-salinity waters where the primary productivity was inferred to be the highest at the time of sampling, with a flux of 11 ± 0.45 mmol C m−2 d−1, compared to 14 ± 0.39 mmol C m−2 d−1 in high salinity waters and 8.5 ± 0.66 mmol C m−2 d−1 in low salinity waters. This study thus implied that natural iron fertilization does not necessarily lead to an enhancement of POC export in STF regions.
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Zhou, K., S. D. Nodder, M. Dai, and J. A. Hall. "Insignificant enhancement of export flux in the highly productive Subtropical Front, east of New Zealand: a high resolution study of particle export fluxes based on <sup>234</sup>Th:<sup>238</sup>U disequilibria." Biogeosciences Discussions 8, no. 5 (September 21, 2011): 9535–76. http://dx.doi.org/10.5194/bgd-8-9535-2011.
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Abstract. We evaluated the downward Particulate Organic Carbon (POC) export fluxes in the Subtropical Frontal zone (STF) of the Southern Ocean. The site is characterized by enhanced primary productivity which has been suggested to be stimulated through so-called natural iron fertilization processes at its northern boundary where iron-depleted subantarctic water (SAW) mixes with oligotrophic, iron-replete subtropical water (STW). We adopted the small-volume 234Th method to achieve highest spatial sampling resolution as possible based on a cruise to the STF to the east New Zealand in austral late autumn-early winter, May–June 2008. The inventories of fluorescence, particulate 234Th and POC observed in the upper 100 m were all elevated in the mid-salinity part of the water type (34.5<S<34.8), compared with low (S<34.5) and high (S>34.8) salinity waters. However, Steady-State 234Th fluxes were similar cross all of the salinity gradient being 1484 in the mid-salinity, and 1761 and 1304 dpm m−2 d−1 in the high and low salinity zones respectively. Bottle POC/Th ratios at the depth of 100 m were used to convert the Th fluxes into POC export flux. The POC flux was again not enhanced in the mid-salinity range where the primary production was highest, being 7.4 mmol C m−2 d−1 as compared to 9.9 mmol C m−2 d−1 in high salinity waters, and 5.9 mmol C m−2 d−1 in low salinity waters. This study implied that natural iron fertilization does not necessarily lead to the enhancement of POC export in STF regions.
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Parkyn, Daryl C., Debra J. Murie, and Edward T. Sherwood. "Salinity Preference in Hatchery-Reared Juvenile Red Drum." Scientific World JOURNAL 2 (2002): 1334–39. http://dx.doi.org/10.1100/tsw.2002.347.
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Juvenile red drum (Sciaenops ocellatus), reared in either 15- or 30-ppt salinity seawater, were tested to determine whether they develop preference for the salinity of the water in which they were cultured. In a two-choice test, large- and small-sized juvenile red drum chose the raceway that matched the seawater in which they were cultured over the other salinity. Additional large and small fish reared in either 15- or 30-ppt salinity water were also tested following a 4-h acclimation period that simulated the duration of transport time from the hatchery to a release site. These fish also showed preference for their original culture salinity. This observed salinity preference in juvenile red drum has implications with respect to movement or residency of hatchery-reared juvenile red drum out-planted into natural coastal systems.
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Price, Lewis, Yong Han, Tefera Angessa, and Chengdao Li. "Molecular Pathways of WRKY Genes in Regulating Plant Salinity Tolerance." International Journal of Molecular Sciences 23, no. 18 (September 19, 2022): 10947. http://dx.doi.org/10.3390/ijms231810947.
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Salinity is a natural and anthropogenic process that plants overcome using various responses. Salinity imposes a two-phase effect, simplified into the initial osmotic challenges and subsequent salinity-specific ion toxicities from continual exposure to sodium and chloride ions. Plant responses to salinity encompass a complex gene network involving osmotic balance, ion transport, antioxidant response, and hormone signaling pathways typically mediated by transcription factors. One particular transcription factor mega family, WRKY, is a principal regulator of salinity responses. Here, we categorize a collection of known salinity-responding WRKYs and summarize their molecular pathways. WRKYs collectively play a part in regulating osmotic balance, ion transport response, antioxidant response, and hormone signaling pathways in plants. Particular attention is given to the hormone signaling pathway to illuminate the relationship between WRKYs and abscisic acid signaling. Observed trends among WRKYs are highlighted, including group II WRKYs as major regulators of the salinity response. We recommend renaming existing WRKYs and adopting a naming system to a standardized format based on protein structure.
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Lubin, Robert T., A. W. Rourke, and Richard L. Saunders. "Influence of Photoperiod on the Number and Ultrastructure of Gill Chloride Cells of the Atlantic Salmon (Salmo salar) before and during Smoltification." Canadian Journal of Fisheries and Aquatic Sciences 48, no. 7 (July 1, 1991): 1302–7. http://dx.doi.org/10.1139/f91-156.
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Atlantic salmon (Salmo salar) larger than 9 cm held under constant light since October had greater numbers of gill chloride cells in February compared with fish held under simulated natural photoperiod. By April, fish raised under simulated natural photoperiod were able to survive salinity tests, had a threefold increase in Na+/K+ ATPase activity, and had increased chloride cell numbers. These increases and salinity tolerance did not occur in fish raised under constant light. Only fish reared under constant light developed apical pits with large and numerous microvilli.
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Anh, Hoang Ha. "ASSESSMENT OF FARMERS’ PRONE STATE TO NATURAL DISASTERS: A CASE OF MAINSTREAM HYDROPOWER DEVELOPMENT IN THE LOWER MEKONG DELTA, VIETNAM." Vietnam Journal of Science and Technology 54, no. 2A (March 19, 2018): 178. http://dx.doi.org/10.15625/2525-2518/54/2a/11928.
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The study provides a comprehensive view at the prone state of the Mekong Delta under baseline conditions of hydropower development. Communities in Vietnam Mekong Delta have main income sources from rice farming, fishing and aquaculture, so changes in floods pattern or salinity can directly affect people’s livelihoods. Among 13 provinces in Mekong River Delta, there are 9 provinces that have moderate Potential Impact Sub-Index (PII). Tra Vinh has the PII since its population is affected by both floods and salinity more heavily than other provinces. The provinces that have higher PII also have higher Social Vulnerability Index (SVI) to impacts. All provinces except Long An have moderate vulnerability to impacts because Long An not only has low PII but also high Adaptive Capacity Sub-Index (ACI) which makes it less vulnerable. Tra Vinh has highest SVI because of its exposed state to floods and salinity and high poverty rate. The results show that majority of Mekong River Delta are vulnerable to floods and salinity.
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Xu, Shaochun, Yi Zhou, Pengmei Wang, Feng Wang, Xiaomei Zhang, and Ruiting Gu. "Salinity and temperature significantly influence seed germination, seedling establishment, and seedling growth of eelgrassZostera marinaL." PeerJ 4 (November 15, 2016): e2697. http://dx.doi.org/10.7717/peerj.2697.
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Globally, seagrass beds have been recognized as critical yet declining coastal habitats. To mitigate seagrass losses, seagrass restorations have been conducted in worldwide over the past two decades. Seed utilization is considered to be an important approach in seagrass restoration efforts. In this study, we investigated the effects of salinity and temperature on seed germination, seedling establishment, and seedling growth of eelgrassZostera marinaL. (Swan Lake, northern China). We initially tested the effects of salinity (0, 5, 10, 15, 20, 25, 30, 35, and 40 ppt) and water temperature (5, 10, 15, and 20 °C) on seed germination to identify optimal levels. To identify levels of salinity that could potentially limit survival and growth, and, consequently, the spatial distribution of seedlings in temperate estuaries, we then examined the effect of freshwater and other salinity levels (10, 20, and 30 ppt) on seedling growth and establishment to confirm suitable conditions for seedling development. Finally, we examined the effect of transferring germinated seeds from freshwater or low salinity levels (1, 5, and 15 ppt) to natural seawater (32 ppt) on seedling establishment rate (SER) at 15 °C. In our research, we found that: (1) Mature seeds had a considerably lower moisture content than immature seeds; therefore, moisture content may be a potential indicator ofZ. marinaseed maturity; (2) Seed germination significantly increased at low salinity (p < 0.001) and high temperature (p < 0.001). Salinity had a much stronger influence on seed germination than temperature. Maximum seed germination (88.67 ± 5.77%) was recorded in freshwater at 15 °C; (3) Freshwater and low salinity levels (< 20 ppt) increased germination but had a strong negative effect on seedling morphology (number of leaves per seedling reduced from 2 to 0, and maximum seedling leaf length reduced from 4.48 to 0 cm) and growth (seedling biomass reduced by 46.15–66.67% and maximum seedling length reduced by 21.16–69.50%). However,Z. marinaperformed almost equally well at salinities of 20 and 30 ppt. Very few germinated seeds completed leaf differentiation and seedling establishment in freshwater or at low salinity, implying that freshwater and low salinity may potentially limit the distribution of this species in coastal and estuarine waters. Therefore, the optimum salinity forZ. marinaseedling establishment and colonization appears to be above 20 ppt in natural beds; (4) Seeds germinated in freshwater or at low salinity levels could be transferred to natural seawater to accomplish seedling establishment and colonization. This may be the optimal method for the adoption of seed utilization in seagrass restoration. We also identified seven stages of seed germination and seedling metamorphosis in order to characterize growth and developmental characteristics. Our results may serve as useful information forZ. marinahabitat establishment and restoration programs.
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Wang, Yuan, Da Xi Liu, Mei Ting Ju, Zhao Hui Jin, and Tie Long Li. "The Effect of Seawater Salinity on the Equilibrium Time of Oxidation Reduction Potential." Advanced Materials Research 301-303 (July 2011): 1648–51. http://dx.doi.org/10.4028/www.scientific.net/amr.301-303.1648.
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On the basis of a large number of continuous monitoring experiments for the five-line salinity of seawater, and the uncertainty of natural seawater oxidation reduction potential (ORP) is 2.2mV, the effect of seawater salinity on the equilibrium time of ORP is studied qualitatively and quantitatively. The results indicated that the greater the salinity, the longer the time of reaching to ORP equilibrium value, the longer the equilibrium time of the seawater ORP value. It is showed that the ORP equilibrium value was obtained at 30minutes, 90minutes, 120minutes, 240minutes and 300minutes from seawater with salinity as 5,20,30,35 and 40, respectively, and the equilibrium time was more than 12 hours. Accuracy and stability of the equilibrium time of seawater ORP value under different salinity can provide technical support for metrological verification of ORP sensor.
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Marraskuranto, Endar, Tri J. Raharjo, Rina S. Kasiamdari, and Tri R. Nuringtyas. "Influence of Salinity on Growth and Phycoerythrin Production of Rhodomonas salina." Squalen Bulletin of Marine and Fisheries Postharvest and Biotechnology 13, no. 3 (December 30, 2018): 109. http://dx.doi.org/10.15578/squalen.v13i3.365.
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Microalgae is a photoautotroph organism capable of producing various photosynthetic pigments with diverse beneficial properties. Rhodomonas salina, a Cryptophyte cell, contains only phycoerythrin as its phycobiliprotein pigment. The effects of salinity on growth and phycoerythrin concentration were investigated. Microalgae R. salina were grown in natural sea water with salinity of 33‰ and 50‰.The microalgae was batch-cultured in f/2 medium at light irradiation of 1100 lux, temperature of 24–26 oC, and photoperiode of 12 h : 12 h. The microalgae cell density was directly calculated using haemacytometer. The concentration of phycoerythrin was determined by spectrophotometric method. The cell density and phycoerythrin concentration were monitored every 4 days for 20 days of cell growth. Results showed that salinity did not affect significantly both on growth and phycoerythrin concentration extracted from R. salina biomass (p>0.05; a = 0.05). At both salinity, maximum phycoerythrin concentration were reached on day 8. There was a positive correlation between cell density and phycoerythrin concentration from day 1 to day 8 of cell growth. Microalgae R. salina which was grown in natural seawater with salinity of 33‰ achieved the highest cell density of 8.4 x 105 cells/mL and the phycoerythrin concentration of 0.19 mg. 10-5 cell on day 8 of the culture. The highest phycoerythrin concentration was obtained on day 16 of the culture i.e 0.27 mg. 10-5 cell.Keywords: cell density, growth media, phycoerythrin, Rhodomonas salina, salinity
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Maichak de Carvalho, Barbara, Daniel Vicente Pupo, Alejandra Vanina Volpedo, Jorge Pisonero, Ana Méndez, and Esteban Avigliano. "Spatial environmental variability of natural markers and habitat use of Cathorops spixii in a neotropical estuary from otolith chemistry." Journal of the Marine Biological Association of the United Kingdom 100, no. 5 (August 2020): 783–93. http://dx.doi.org/10.1017/s0025315420000752.
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AbstractThe goal of this study was to study the distribution of potential habitat markers (Sr/Ca, Ba/Ca, Mn/Ca and Li/Ca) in water from the Paranaguá Estuarine Complex (Brazil) and to study habitat use patterns of Cathorops spixii through ontogeny employing otolith microchemistry. Fish were caught from three sampling sites while water samples were collected at eight stations covering a salinity range from 4.5–33. Elemental concentrations in otolith and water were determined by LA-ICP-MS and ICP-MS, respectively. When the relationship between salinity and elements or ratios in water was studied, significant positive relationships were found for Sr, Li, Ca, Sr/Ca, and negative for Ba, Mn, Ba/Ca and Mn/Ca (P < 0.05). No relationship was observed between water Li/Ca and salinity. A significant positive correlation was found between otolith edge Sr/Ca and salinity (r = 0.63; P < 0.05), positioning this ratio as the best natural tag for reconstructing environmental histories of C. spixii. Change point analysis (CPA) based on otolith Sr/Ca signature through ontogeny revealed potential migrations between environments with different salinity. According to CPA, the number of displacements among different salinities ranged from 3–9 (6.1 ± 1.9), suggesting high plasticity in the migratory patterns. Ba/Ca, Li/Ca and Mn/Ca peaks were observed on the outer margin of the primordium, and could be influenced by physiological, environmental and maternal factors.
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Paramygin, Vladimir, Y. Sheng, Justin Davis, and Karen Herrington. "Simulating the Response of Estuarine Salinity to Natural and Anthropogenic Controls." Journal of Marine Science and Engineering 4, no. 4 (November 16, 2016): 76. http://dx.doi.org/10.3390/jmse4040076.
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K., Entsar, and M. Gharib. "Optimization of Sweet Pepper Productivity in Greenhouse under Natural Salinity Stress." Journal of Plant Production 12, no. 8 (August 1, 2021): 921–28. http://dx.doi.org/10.21608/jpp.2021.198867.
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Druva-Lūsīte, Ieva, Andis Karlsons, Una Andersone-Ozola, Baiba Ieviņa, Jevgeņija Nečajeva, Ineta Samsone, and Gederts Ievinsh. "Physiological Performance of a Coastal Marsh Plant Hydrocotyle vulgaris in Natural Conditions in Relation to Mineral Nutrition and Mycorrhizal Symbiosis." Proceedings of the Latvian Academy of Sciences. Section B. Natural, Exact, and Applied Sciences. 74, no. 4 (August 1, 2020): 252–62. http://dx.doi.org/10.2478/prolas-2020-0040.
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AbstractFluctuating soil salinity and competition for light are the main factors affecting plant distribution and performance in coastal salt marshes. The aim of the present study was to assess plant performance by means of non-destructive instrumental methods in a highly heterogeneous natural habitat. More specifically, environmental factors affecting growth and physiological performance of a clonal plant Hydrocotyle vulgaris L. were investigated. Changes in soil salinity, soil mineral characteristics, leaf nutrient concentrations, morphological parameters, chlorophyll fluorescence, and mycorrhizal symbiosis were analysed in different experimental plots of naturally growing H. vulgaris plants. The dynamic nature of interaction between sea water flooding-affected changes in soil salinity and competition-dependent changes in light availability led to micro-environmental heterogeneity differentially affecting physiological performance and growth of H. vulgaris in natural conditions. Plant growth was mostly affected by intensity of photosynthetically active radiation in the respective plots. Increased growth rate in shaded conditions specifically pointed to shade tolerance strategy of H. vulgaris. High heterogeneity of mineral nutrients between the plots was established. However, considerable plasticity of metabolism in respect to highly variable soil concentration of mineral nutrients together with effective mineral adaptation mechanisms ensured optimal supply of material for growth. Photochemistry of photosynthesis was only marginally affected by differences in microenvironmental conditions as shown by respective changes in chlorophyll a fluorescence parameters. Mycorrhizal symbiosis was stimulated by moderately increasing soil salinity and suppressed by relatively high salinity. When the effect of soil salinity was omitted, intensity of mycorrhizal symbiosis was positively associated with intensity of photo-synthetically active radiation. In general, a relatively high stable level of photosynthetic performance across a wide range of micro-environmental conditions indicates an adequate level of physiological adaptation of H. vulgaris to conditions of a coastal salt marsh. The present data clearly reflect complex interactions between environmental factors and plastic physiological responses of H. vulgaris.
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Rios-López, Neftalí. "Effects of increased salinity on tadpoles of two anurans from a Caribbean coastal wetland in relation to their natural abundance." Amphibia-Reptilia 29, no. 1 (2008): 7–18. http://dx.doi.org/10.1163/156853808783431451.
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Abstract Many amphibians depend on wetland ecosystems for reproduction and survival, and coastal wetlands are not the exception. Recent advances on climate change research predict a reduction in land cover of coastal wetlands due to sea-level rise in response to global warming. Although this scenario will contribute to further amphibian population declines worldwide the impacts of sea-level rise and its related salt water intrusion on anuran assemblages in coastal wetlands remain largely unknown. I documented patterns of abundance of the native Caribbean white-lipped frog (Leptodactylus albilabris) and the introduced marine toad (Bufo marinus) along an inland-to-coastal salinity gradient in Puerto Rico. In addition, I investigated the effects of increasing salinity on larval growth and survival to metamorphosis in L. albilabris and B. marinus in laboratory experiments. In the field, relative abundance of adults of L. albilabris decreased with increasing salinity, while B. marinus showed the opposite pattern. Laboratory experiments with L. albilabris and B. marinus revealed that percentage of larvae surviving to metamorphosis in both species was greatly reduced in 22-25% seawater (8 ppt), which is within salinity levels found in their natural distribution. In this salinity level, the native L. albilabris showed ∼100% metamorphosis failure while the introduced B. marinus showed ∼60% metamorphosis failure. The reduction in metamorphosis was due to high mortality in L. albilabris and was accompanied with morphological abnormalities in B. marinus. Tadpoles of only L. albilabris reared for four weeks showed significant weight loss at 8 ppt, but showed no difference in length. These results suggest that anuran tadpoles may be living near their physiological limit for salinity in the studied wetland. Conservation implications are profound, however, as salt water intrusion and urban encroaching inland may result in anuran population replacement, from native species to introduced species in this wetland.
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van de Velde, Sabrina, Elisabeth L. Jorissen, Thomas A. Neubauer, Silviu Radan, Ana Bianca Pavel, Marius Stoica, Christiaan G. C. Van Baak, et al. "A conservation palaeobiological approach to assess faunal response of threatened biota under natural and anthropogenic environmental change." Biogeosciences 16, no. 12 (June 17, 2019): 2423–42. http://dx.doi.org/10.5194/bg-16-2423-2019.
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Abstract. Palaeoecological records are required to test ecological hypotheses necessary for conservation strategies as short-term observations can insufficiently capture natural variability and identify drivers of biotic change. Here, we demonstrate the importance of an integrated conservation palaeobiology approach when making validated decisions for conservation and mitigating action. Our model system is the Razim–Sinoie lake complex (RSL) in the Danube Delta (Black Sea coast, Romania), a dynamic coastal lake system hosting unique Pontocaspian mollusc species that are now severely under threat. The Pontocaspians refer to an endemic species group that evolved in the Black Sea and Caspian Sea basins under reduced salinity settings over the past few million years. The natural, pre-industrial RSL contained a salinity gradient from fresh to mesohaline (18 ppm) until human intervention reduced the inflow of mesohaline Black Sea water into the lake system. We reconstruct the evolution of the RSL over the past 2000 years from integrated sedimentary facies and faunal analyses based on 11 age-dated sediment cores and investigate the response of mollusc species and communities to those past environmental changes. Three species associations (“marine”, “Pontocaspian” and “freshwater”) exist and their spatio-temporal shifts through the system are documented. Variable salinity gradients developed, with marine settings (and faunas) dominating in the southern part of the system and freshwater conditions (and faunas) in the northern and western parts. Pontocaspian species have mostly occurred in the centre of the RSL within the marine–freshwater salinity gradient. Today, freshwater species dominate the entire system, and only a single Pontocaspian species (Monodacna colorata) is found alive. We show that the human-induced reduced marine influence in the system has been a major driver of the decline of the endemic Pontocaspian biota. It urges improved conservation action by re-establishing a salinity gradient in the lake system to preserve these unique species.
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WONG, HIN-CHUNG, and SHU-HUI LIU. "Characterization of the Low-Salinity Stress in Vibrio vulnificus." Journal of Food Protection 71, no. 2 (February 1, 2008): 416–19. http://dx.doi.org/10.4315/0362-028x-71.2.416.
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Vibrio vulnificus is a marine pathogenic bacterium commonly found in seawater or seafood. This organism encounters low-salinity stress in its natural environment and during food processing. This study was designed to investigate the response of V. vulnificus YJ03 to lethal low salinity (0.04% NaCl) and its adaptation to sublethal salinity (0.12% NaCl with 20 amino acids added). A short period in the nonculturable state was induced by lethal low-salinity stress followed by cell death after 30 min of stress. Addition of 1 mM glycine betaine or 0.5 mM sucrose reduced the damage. Low-salinity adaptation was achieved in the exponential-phase cells but not in the stationary-phase cells. Significant protection against lethal low-salinity stress was attained when the cells were adapted for as little as 1.5 min. The adapted cells were significantly protected against lethal low salinity and 2.4% sodium sorbate but sensitized to the challenge of heat (52°C) and acid (pH 3.2). Nonlethal lowsalinity treatment of seafood should be avoided to prevent stress adaptation of V. vulnificus.