Addition Of Salt Water Research Articles

Tinjauan Kuat Tekan Dan Absorbsi Mortar Yang Mengandung Air Garam

Mortar is a building material that serves to glue bricks, bricks, plaster, and so on. As an adhesive, mortar has a viscosity that is useful in determining compressive strength. In the manufacture of mortar, SNI 03-6882-2002 requires the use of clean fresh water, but in reality, as an archipelagic country, some of the islands in Indonesia are isolated from fresh water. As a result, freshwater becomes an expensive item, because it is imported from other areas, so it requires transportation costs. If the mortar is required to use water according to SNI standards, the project implementation costs will be expensive. In areas that do not have adequate fresh water, mortar is made using water obtained on-site, including brackish, salt, and sea water. Seawater contains elements of NaCl salts which can bind Calcium Hydroxide (CaOH) compounds, reducing the CaOH compounds in the mortar will increase the compressive strength of the mortar. In this study, a review of brine as a mixture of mortar materials was carried out with the aim of knowing the performance of mortar containing salt water by compressive strength test and Absorption test. The amount of salt water added to the mortar mixture is 0%; 0.5%; 1%; 1.5%; 2%; 2.5% ; 3%; 3.5% of the volume of water used as a mortar mix. Cube test object measuring 50x50x50 mm3 in the amount of 5 in each treatment, made from a mixture of 1PC: 2.75 Sand (based on weight ratio), with a water-cement factor (FAS) of 0.45. The test results obtained the compressive strength value of the mortar with the addition of salt water can reduce the compressive strength value but the use of brine with a content of 3.5% is still in the category of minimum permissible pressure according to SNI03-6882-2002. While the absorption value of the mortar can increase fiber strength with increasing addition of 3.0% brine.

Effects of constant and fluctuating saltwater addition on CH4 fluxes and methanogens of a tidal freshwater wetland: A mesocosm study

The importance of salinity in regulating CH4 emissions from coastal tidal wetlands has been widely recognized. However, the different effects of constant versus fluctuating salinity increases on CH4 emission and methanogens in both tidal freshwater marsh and floodplains are not yet well understood. We constructed mesocosm experiments on both a Cyperus malaccensis marsh and an adjacent non-vegetation-covered tidal floodplain over one year. We examined the effects of constant freshwater (CF), constant salinity (CS), and fluctuating salinity (FS) on porewater geochemistry, CH4 flux, methanogen abundance, diversity, and community structure in the tidal marsh and floodplain. Compared with CF treatment, methanogen abundance and Chao1 index were significantly lower in the marsh mesocosms under FS and CS treatment, but only in the floodplain mesocosms under CS treatment. CS treatment significantly reduced the proportion of Methanosarcinales but significantly increased the proportion of Methanobacteriales. Porewater SO42− and Cl− concentrations and pH were important factors affecting methanogen abundance and diversity. Both the CS and FS treatments considerably reduced CH4 fluxes in marsh and floodplain mesocosms; the main factor impacting CH4 flux was porewater dissolved CH4 concentration, and both methanogen abundance and Chao1 index were positively correlated with CH4 flux. Our results suggest that both continuous saltwater intrusion caused by sea-level rise and pulse saltwater intrusion perhaps caused by typhoons could reduce CH4 flux from subtropical estuarine tidal freshwater wetlands.

Response of Melia azedarach L. tree seedlings to the addition of salt water and yeast

Response of Melia azedarach L. tree seedlings to the addition of salt water and yeast

Effect of saltwater intrusion on activated sludge flocculation.

Saltwater addition negatively impacted the settling properties of the activated sludge in a sequencing batch reactor, which in turn caused the effluent quality and the dewatering properties to deteriorate. Experiments showed that increasing sodium ion concentrations above 1meq/L interfered with bio-flocculation by ion exchange of calcium ions displaced by sodium in mixed liquor flocs, causing increases in the sludge volume index, total suspended solids, and chemical oxygen demand concentrations of the final effluent and in the times of the time to filter test of the mixed liquor. Experiments were also conducted to reverse mixed liquor de-flocculation by adding calcium ions in wastewater with different sodium chloride concentrations and a positive relationship was found between calcium ion added and improved effluent quality. Calcium ion concentrations above 1.6meq/L proved to be beneficial for adhesion of microbial aggregates leading to the formation of stable flocs and improved sludge dewatering by reversing the ion exchange phenomenon observed with sodium concentrations above 1meq/L. Monovalent-to-divalent ratios did not provide predictive information on de-flocculation. Hence, individual ion concentrations in addition to monovalent-to-divalent cation ratios are important in the onset of de-flocculation effects while a system-specific concentration threshold was measured under which no adverse effects were observed. PRACTITIONER POINTS: The adverse effects of varying concentrations of sodium chloride on the biological process affecting bioflocculation and effluent quality. Impact of sodium on the health of the mixed liquor as well as on dewatering processes. Prediction of sea level rise due to climate change will impact utilities situated along the coast with saltwater intrusion problems. Management of dewatered flows containing saltwater from onsite construction Identify management practices to reduce the impact of saltwater on the wastewater treatment plant.

Carbon mineralization in tidal freshwater marsh soils at the intersection of low-level saltwater intrusion and ferric iron loading

Low-level saltwater intrusion and ferric iron (Fe(III)) loading are predicted for many mineral tidal freshwater ecosystems under sea-level rise. To assess their effects on the carbon mineralization processes, in-situ experiments were conducted with four treatments: Fe(III) amendment, saltwater addition, saltwater addition plus Fe(III) amendment, and a control. Soil and porewater samples (0–30 cm) were collected to assess geochemical properties and soil incubation on Days 460 and 580 after the start of the experiment. Saltwater addition increased the salinity from freshwater (0.1 mg·g−1) to oligohaline (<2 mg·g−1) and elevated the concentrations of porewater Cl−, SO42−, and NH4+. Fe(III) amendment increased the concentrations of soil Fe(III), Fe(II), and total reduced sulfur (TRS). Both Fe(III) amendment and saltwater addition enhanced the belowground biomass of marsh plants, while neither affected the total organic carbon (TOC) and total nitrogen (TN) pools or their ratios. Both Fe(III) amendment and saltwater addition improved the overall mineralization rates (i.e., CO2 plus CH4 production) of the soil at 0–10 cm depths. Methanogenesis decreased under both Fe(III) amendment and saltwater addition. Strong negative relationships were observed between methanogenesis rates and the concentrations of porewater Cl− and SO42−, and soil Fe(III). Relative to the individual Fe(III) and saltwater treatments, the combined treatment did not further promote overall mineralization rates or further impede methanogenesis potential. Methanogenesis and Fe(III) reduction co-dominated the overall mineralization in the control treatment. Individual loading of Fe(III) and saltwater into the soils induced the predominance of Fe(III) and sulfate reduction, respectively. Under the combined treatment, microbial Fe(III) and sulfate reduction co-dominated the overall mineralization, but restrained each other. The shifts in the partitioning of mineralization pathways among treatments were primarily influenced by porewater Cl− and SO42−, followed by Fe(III), and then DOC. Together, the results suggest that the projected modest levels of saltwater intrusion and Fe(III) loading may simultaneously accelerate the belowground C input and mineralization rates, shifting anaerobic pathways away from CH4 production towards Fe(III) and sulfate reduction.

Greenhouse gas fluxes and porewater geochemistry following short-term pulses of saltwater and Fe(III) in a subtropical tidal freshwater estuarine marsh

Estuarine tidal freshwater riparian marshes experience short-term saltwater intrusions (caused by typhoons and hurricanes) and Fe(III) inputs (associated with run-off from upstream basins during rain events). However, the effects of Fe(III) inputs and of simultaneous increases of saltwater and Fe(III) on greenhouse gas (GHG) fluxes and porewater geochemistry of estuarine tidal freshwater wetlands have not yet been studied. This study applied monthly in-situ experimental manipulations of saltwater and Fe(III) additions within a tidal freshwater wetland (the Min River estuary, southeast China) dominated by Sagittaria trifolia, over two years. We examined changes in porewater geochemistry (i.e., SO42–, Cl–, NH4+, and NO3–), ecosystem GHG (i.e., CH4, CO2, and N2O) fluxes, and soil denitrification rates. Short-term saltwater intrusions did not cause a large increase in soil salinity but did decrease CH4 fluxes. Fe(III) additions also greatly decreased CH4 fluxes, however, the combined addition of saltwater and Fe(III) did not have a synergistic effect on the reduction of CH4 emissions. Further, CO2 emissions did not significantly change in response to either the individual or the combined saltwater and Fe(III) additions. Most interestingly, we found that the combined addition of saltwater and Fe(III) led to an increase in N2O fluxes of an order of magnitude compared to the control. Based on the results of sustained-flux global warming potential (SGWP) and sustained-flux global cooling potential (SGCP) models, our findings suggest that short-term pulses of both individual saltwater and the combination of saltwater and Fe(III) caused by storm tides and soil erosion following a typhoon or hurricane event could reduce the CO2-equivalent flux from subtropical estuarine tidal freshwater wetlands, although the effects may be temporary.

Determinants of rice by-products utilization as feed and their management in Ethiopia: the case of Fogera District

Asmare B, Yayeh Z. 2018. Determinants of rice by-products utilization as feed and their management in Ethiopia: the case of Fogera District. Asian J Agric 2: 1-7. The study was conducted with the objective to determine the status of farmers’ rice byproduct utilization as feed in Fogera district, northwestern Ethiopia. Eighty smallholder farmers were selected purposely based on livestock population and rice production access. A semi-structured questionnaire was administered to select farmers systematically. The collected data was analyzed using SPSS descriptive statistical analysis. The result indicated that the majority of respondents in the study area were with the range from 31 to 50 years (55%). Education status of respondents showed that the majority of household heads were able to read and write (27.5%) followed by elementary school (26.25%) and high school (17.5%) completed. The main dry season feed in the majority of households (46.25%) was found to be grazing and crop residues. The majority (64.62%) of farmers used rice by-products as livestock feed, followed by both feed and house construction. Types of by-products used for animal feed by respondent’s elucidated majority (61.5%) used rice straw, considerable proportion (26.15%) rice bran and (12.30%) used both straw and bran for animal feed based on availability. The sources of rice by-products indicated for many of respondents (66.7%) was farm produced, 18.5% use purchased and 18.4% get rice by-products both from farm produced and purchasing for their animal feed. Type of animals fed rice byproducts including cattle in the case of majority of respondents (49.23%), cattle and equine, followed (24.62%), and all animals (13.85%), respectively. In livestock owners, rice by-products are fed to livestock as sole feed and mixed with other feeds, however, the majority (69.2%) of households provides sole followed by both sole and mixed with other feeds (16.9%). Many of the respondents (55%) apply drying followed by addition of salt water (22.5%) as method of improving the rice by-products. The main constraints observed in rice by-products utilization as feed were seasonal deficiency of by-products (25.5%) followed by lack of awareness (16.25%).Though these problems prevailed in the study area, rice by-products are being used as a major crop residue feed with little or no improvement applied. Generally, it can be included that rice by-products were found very important feed resources in the rice dominated farming system of Fogera district. To exploit these products properly, farmers need to be assisted through proper agricultural extension service and supply in the form of credit service. Moreover, further on detailed on-farm experimentation should be done to demonstrate better utilization of the products as livestock feed.

Ignitability of crude oil and its oil-in-water products at arctic temperature

A novel platform and procedure were developed to characterize the ignitability of Alaska North Slope (ANS) crude oil and its water-in-oil products with water content up to 60% at low temperatures (−20–0°C). Time to ignition, critical heat flux, in-depth temperature profiles were investigated. It was observed that a cold boundary and consequent low oil temperature increased the thermal inertia of the oil/mixture and consequently the time to sustained ignition also increased. As the water content in the ANS water-in-oil mixture increased, the critical heat flux for ignition was found to increase. This is mainly because of an increase in the thermal conductivity of the mixture with the addition of saltwater. The results of the study can be used towards design of ignition strategies and technologies for in situ burning of oil spills in cold climates such as the Arctic.

Bensulfuron‐methyl Biodegradation and Microbial Parameters in a Riparian Soil as Affected by Simulated Saltwater Incursion

AbstractSoil salinization due to saltwater incursion, is a major threat to microbial population and thus strongly alters biogeochemical processes in a freshwater riparian of coastal estuary region. An incubation experiment was conducted to investigate the effects of simulated saltwater treatments with different percentages of artificial seawater on biodegradation dynamics of herbicide bensulfuron‐methyl (BSM) and microbial ecophysiological parameters in a riparian soil in Chongming Island, China. The results showed that saltwater addition with 10% seawater significantly increased the biodegradation efficiency of BSM with the lowest residual concentration among all the treatments. However, BSM degradation was markedly decreased in the riparian soil with high levels of saltwater treatment. The half‐lives for 20% and 50% seawater treatments were prolonged by 4.9% and 21.1%, respectively, as compared to no saltwater treatment. Throughout the incubation period, 10% seawater treatment showed significantly stimulating effects on microbial parameters in the BSM‐spiked riparian soil. At the end of incubation experiment, flourescein diacetate (FDA) hydrolysis rate, soil microbial adenosine triphosphate (ATP), and basal soil respiration (BSR) in the BSM‐spiked riparian soil with 10% seawater were 64.2%, 48.9%, and 39.4% higher than those with no saltwater treatment, respectively. In contrast, saltwater treatment with 50% seawater significantly inhibited microbial activities, relative to no saltwater treatment. Especially, FDA hydrolysis rate, microbial ATP, and BSR were decreased by 74.1%, 69.8%, and 63.4%, respectively, as compared to no saltwater treatment. Our data indicate that different levels of simulated saltwater incursion can exert variable effects on microbial ecophysiological parameters, and consequently resulted in the difference in biodegradation dynamics of herbicide in the herbicide‐spiked riparian soil.

Enzyme activities and glyphosate biodegradation in a riparian soil affected by simulated saltwater incursion

AbstractSoil salinization due to saltwater incursion, is a major threat to biochemical activities and thus strongly alters biogeochemical processes in a freshwater riparian of coastal estuary region. A pot incubation experiment was conducted to investigate the effects of simulated saltwater incursion on some key enzymatic activities and biodegradation dynamics of herbicide glyphosate in a riparian soil in Chongming Island located in the Yangtze River estuary, China. The results showed that saltwater addition with 10% artificial seawater significantly increased the biodegradation efficiency of glyphosate with the lowest residual concentration among all the treatments. However, glyphosate degradation was markedly decreased in the riparian soil with high levels of saltwater treatment. As compared with no saltwater treatment, the half-lives for 20% and 50% seawater treatments were prolonged by 4.9% and 21.1%, respectively. Throughout the incubation period, saltwater addition with 10% seawater stimulated the enzymatic activities in the glyphosate-spiked riparian soil, as compared to the treatment with 0% seawater. Flourescein diacetate (FDA) hydrolysis rate, dehydrogenase activity (DHA), catalase activity, and alkaline phosphatase activity in the glyphosate-spiked riparian soil treated with 10% seawater were 68.5%, 49.2%, 38.7%, and 28.6% higher than those for no saltwater treatment, respectively. The effect of 20% seawater treatment on the glyphosate-spiked riparian soil enzymatic activities fluctuated between promotion and inhibition depending on the type of enzymes. Soil enzymatic activities were severely depressed by increasing salinity level with 50% seawater treatment significantly inhibited, relative to no saltwater treatment. Especially, FDA hydrolysis rate and DHA were decreased by 73.8% and 64.8%, respectively, as compared to no saltwater treatment. Glyphosate degradation percentages were strongly positively correlated to the FDA hydrolysis rate and DHA, indicating that as compared to the other enzymes, the two enzymes contributed more to the herbicide biodegradation in the salt-affected riparian soil.

Lime stabilisation of the chicoco mud of the Niger Delta

Chicoco mud is a very soft and extremely compressible organic marine mud found extensively and to considerable depths within the saline tidal flat or mangrove swamp of the Niger delta region in southern Nigeria. Natural chicoco mud is highly compressible barely able to support an average human weight but air-dried chicoco has been used successfully by the natives for shore protection, etc. especially if placed above water. In this study, varying percentages (ranging from 1% to 9%) of industrial and locally produced (from periwinkle shells) slaked-lime were used to stabilise chicoco. It was observed that neutralisation of acidic “air-dried” chicoco by basic lime inhibited the expected ion-exchange reaction and its attendant improvement in mechanical properties. As a result and as lime (industrial or locally-produced) content increases, maximum dry density (MDD) decreases, optimum moisture content (OMC) decreases while unsoaked CBR maximises within low lime content of about 4%. Also, significant improvement in all three parameters (MDD, OMC and CBR) was recorded with saltwater addition. However and with maximum unsoaked CBR of only 12.5%, lime-stabilised chicoco can only produce subgrade materials in roadworks, i.e. not unsuitable for sub-base and base-course materials.Keywords: chicoco mud, Niger delta, lime, periwinkle, stabilisationGlobal Journal of Engineering Research Vol.4 (1&2) 2005: 69-73

Stress-reducing methods for releases of Atlantic salmon (Salmo salar) smolts in Norway

One-year-old, hatchery-reared Atlantic salmon ( Salmo salar ) smolts were Carlin-tagged to test the effects of light sedation and salt water addition during transporting as well as releasing methods on migratory behavior and marine survival in northern Norway. A total of 1600 salmon were tagged for the migratory behavior study in the Halselva River. The fish were transported in water containing either 1 g l −1 metomidate or 11 g l −1 balanced sea salt (Instant Ocean), or a combination of the two. The groups were then allowed to recover for 2 days in net pens in the river, after which they were permitted to migrate freely from the net pens located 1 km upstream from the fish trap. These groups were compared to the untreated groups, which were released directly into the river at the same releasing site at the same time. The results showed that brackish water with metomidate as transport medium, and/or recovery after transport led to improved recaptures of smolts compared to untreated controls. In addition, two groups of approximately 3000 Carlin-tagged Atlantic salmon were transported in 1998 by helicopter from the research station to the nearby Alta River (1-h transport time, including loading) and either released directly into the river or kept in a net pen in the river for 7 days before release. The same releases were performed in 1999. Recaptures of adult salmon in the Alta River were 0.43% and 1.43% (1998 releases) and 1.23% and 1.89% (1999 releases) for smolts released either directly or allowed 7 days to recover in the river before release, respectively. These results shows that the use of stress-reducing methods, especially recovery after transport, can improve both the migratory behavior and marine survival of smolt releases.

Thermocline and intermediate water communication between the south Atlantic and Indian oceans

A conductivity‐temperature‐depth and tracer chemistry section in the southeast South Atlantic in December 1989 and January 1990 presents strong evidence that there is a significant interocean exchange of thermocline and intermediate water between the South Atlantic and Indian oceans. Eastward flowing water at 10°W composed of South Atlantic Central (thermocline) Water is too enriched with chlorofluoromethanes 11 and 12 and oxygen to be the sole source of similar θ‐S water within the northward flowing Benguela Current. About two thirds of the Benguela Current thermocline transport is drawn from the Indian Ocean; the rest is South Atlantic water that has folded into the Benguela Current in association with the Agulhas eddy‐shedding process. South Atlantic Central water passes in the Indian Ocean by a route to the south of the Agulhas Return Current. The South Atlantic water loops back to the Atlantic within the Indian Ocean, perhaps mostly within the Agulhas recirculation cell of the southwest Indian Ocean. Linkage of Atlantic and Indian Ocean water diminishes with increasing depth; it extends through the lower thermocline into the Antarctic Intermediate Water (AAIW) (about 50% is derived from the Indian Ocean) but not into the deep water. While much of the interocean exchange remains on an approximate horizontal “isopycnal” plane, as much as 10 × 106 m3 s−1 of Indian Ocean water within the 25 × 106 m3 s−1 Benguela Current, mostly derived from the lower thermocline and AAIW, may balance deeper Atlantic export of North Atlantic Deep Water (NADW). The addition of salt water from the evaporative Indian Ocean into the South Atlantic Ocean thermocline and AAIW levels may precondition the Atlantic for NADW formation. While AAIW seems to be the chief feed for NADW, the bulk of it enters the subtropical South Atlantic, spiked with Indian Ocean salt, within the Benguela Current rather than along the western boundary of the South Atlantic.