A blow to boundaries

Optimizing drip irrigation with alternate use of fresh and brackish waters by analyzing salt stress: The experimental and simulation approaches

Problems in estimating self-supplied industrial water use by indirect methods, the California example

برای بررسی اثر سطوح شوری آب آبیاری و زمان شروع آبیاری با آب شور و لب‌شور بر خصوصیات کمی خربزه دیررس، آزمایشی با 7 تیمار و 3 تکرار در قالب بلوک‌های کامل تصادفی با استفاده از روش آبیاری قطره‌ای نواری، در مرکز تحقیقات کشاورزی و منابع طبیعی خراسان رضوی انجام شد. تیمارهای آبیاری عبارت بودند از: 1- آبیاری با آب شیرین (6/0 دسی‌زیمنس بر متر) از ابتدای کاشت تا انتهای فصل برداشت، 2- آبیاری با آب با شوری 3 دسی‌زیمنس برمتر از ابتدا تا انتهای فصل داشت، 3-آبیاری با آب با شوری 6 دسی‌زیمنس بر متر از ابتدا تا انتهای فصل، 4- آبیاری با آب با شوری 6 دسی‌زیمنس بر متر از 20 روز بعد از جوانه‌زنی تا انتها، 5- آبیاری با آب با شوری 3 دسی‌زیمنس بر متر از 20 روز بعد از جوانه‌زنی تا انتها، 6- آبیاری با آب با شوری 6 دسی‌زیمنس بر متر از 40 روز بعد از جوانه‌زنی تا انتها و 7- آبیاری با آب با شوری 3 دسی زیمنس بر متر از 40 روز بعد از جوانه‌زنی تا انتهای فصل داشت. نتایج نشان داد که، شوری آب بر عملکرد کل، عملکرد اقتصادی و کارآیی مصرف آب آبیاری تاثیر معنی‌داری داشت. بالاترین عملکرد کل و عملکرد اقتصادی و کارآیی مصرف آب آبیاری از تیمار شاهد بدست آمد که تفاوت آن‌ها با تیمارهای آب شور و لب‌شور معنی‌دار بود. در ضمن تفاوت بین عملکردهای تیمارهای شور و لب‌شور معنی‌دار نبودند. آبیاری با آب شیرین در اوایل دوره رشد باعث افزایش محصول نشده بلکه، باعث وارد شدن تنش بیشتر به گیاه می‌شود.

Summary Current models estimating impact of habitat loss on biodiversity in the face of global climate change usually project only percentages of species ‘committed to extinction’ on an uncertain time‐scale. Here, we show that this limitation can be overcome using an empirically derived ‘background extinction rate–area’ curve to estimate natural rates and project future rates of freshwater fish extinction following variations in river drainage area resulting from global climate change. Based on future climatic projections, we quantify future active drainage basin area losses and combine them with the extinction rate–area curve to estimate the future change in extinction rate for each river basin. We then project the number of extinct species in each river basin using a global data base of freshwater fish species richness. The median projected extinction rate owing to climate change conditions is c. 7% higher than the median background extinction rate. A closer look at the pattern reveals great geographical variations highlighting an amplification of aridity by 2090 and subsequent increase in extinction rates in presently semi‐arid and Mediterranean regions. Among the 10% most‐impacted drainage basins, water availability loss will increase background extinction rates by 18·2 times (median value). Projected numbers of extinct species by 2090 show that only 20 river basins among the 1010 analysed would experience fish species extinctions attributable to water availability loss from climate change. Predicted numbers of extinct species for these rivers range from 1 to 5. Synthesis and applications. Our results strongly contrast with previous alarming predictions of huge surface‐dependent climate change–driven extinctions for riverine fishes and other taxonomic groups. Furthermore, based on well‐documented fish extinctions from Central and North American drainages over the last century, we also show that recent extinction rates are, on average, 130 times greater than our projected extinction rates from climate change. This last result implies that current anthropogenic threats generate extinction rates in rivers far greater than the ones expected from future water availability loss. We thus argue that conservation actions should be preferentially focused on reducing the impacts of present‐day anthropogenic drivers of riverine fish extinctions.

Water scarcity is a great challenge and a growing problem for all countries. The present researchfocuses on the rational utilization of water resources with different quality through studying the effects of different parameters on water use efficiency and productivity, the investigation used different parameters such as water resources, sowing dates and water shortage on the amount of water applied, water use efficiency, yieldand net return of barley, in a semi-arid region during growing season 2014-2015. A Split plot layout with three replications was used. Two main plots represent water resources (fresh and brackish water). Sub plots were represented by the sowing dates of: 15th Dec.,1st Jan.and 15th Jan.with water supply rates of: full irrigation, 80% and 60% of amount of water requirements. The results indicated that, the highest value of irrigation water quantity using brackish water and fresh water were 2285 m3/fed and 2135 m3/fed respectively at planting date of 15 December to add leaching needs and at 100% of irrigation water, while the lowest value for the quantity of irrigation water using brackish water and fresh water at 60% deficit was1237 m3/fed and 1156 m3/fed respectively at the planting date of January 15 in 60% deficit due to the low number of irrigation times. In the meantime, average water use efficiency was 1.28, 1.46 and 1.53 kg/m3 when using 100%, 80% and 60%, respectively, with a yield reduction of 10% and 38% for the use of water 80% and 60% respectively compared to 100%. The average efficiency of water uses when using brackish water was 1.48, 1.65 and 1.64 kg/m3 when using 100%, 80% and 60% irrigation deficit respectively with a decrease in yield of 13%, 51% for the use of fresh water 80% and 60% respectively compared to 100%.

Magnetized water has been a promising approach to improve crop productivity but the conditions for its effectiveness remain contradictory and inconclusive. The objective of this research was to understand the influences of different magnetized water with varying quality on seed absorption, germination, and early growth of cotton. To this end, a series of experiments involving the seed soaking process, germination test, and pot experiment were carried out to study the effects of different qualities (fresh and brackish water) of magnetized water on seed water absorption, germination, seedling growth, photosynthetic characteristics, and biomass of cotton in 2018. The results showed that the maximum relative water absorption of magnetized fresh and magnetized brackish water relatively increased by 16.76% and 19.75%, respectively, and the magnetic effect time of brackish water was longer than fresh water. The relative promotion effect of magnetized brackish water on cotton seed germination and growth potential was greater than magnetized fresh water. The cotton seeds germination rate under magnetized fresh and magnetized brackish water irrigation relatively increased by 13.14% and 41.86%, respectively, and the relative promoting effect of magnetized brackish water on the vitality indexes and the morphological indexes of cotton seedlings was greater than magnetized fresh water. Unlike non-magnetized water, the net photosynthetic rate (Pn), transpiration rate (Tr), and instantaneous water use efficiency (iWUE) of cotton irrigated with magnetized water increased significantly, while the stomatal limit value (Ls) decreased. The influences of photosynthesis and water use efficiency of cotton under magnetized brackish water were greater than magnetized fresh water. Magnetized fresh water had no significant effect on biomass proportional distribution of cotton but magnetized brackish water irrigation markedly improved the root-to-stem ratio of cotton within a 35.72% range. Therefore, the magnetization of brackish water does improve the growth characteristics of cotton seedlings, and the biological effect of magnetized brackish water is more significant than that of fresh water. It is suggested that magnetized brackish water can be used to irrigate cotton seedlings when freshwater resources are insufficient.

This report is the third in a series of reports sponsored by the U.S. Department of Energy Geothermal Technologies Program in which a range of water-related issues surrounding geothermal power production are evaluated. The first report made an initial attempt at quantifying the life cycle fresh water requirements of geothermal power-generating systems and explored operational and environmental concerns related to the geochemical composition of geothermal fluids. The initial analysis of life cycle fresh water consumption of geothermal power-generating systems identified that operational water requirements consumed the vast majority of water across the life cycle. However, it relied upon limited operational water consumption data and did not account for belowground operational losses for enhanced geothermal systems (EGSs). A second report presented an initial assessment of fresh water demand for future growth in utility-scale geothermal power generation. The current analysis builds upon this work to improve life cycle fresh water consumption estimates and incorporates regional water availability into the resource assessment to improve the identification of areas where future growth in geothermal electricity generation may encounter water challenges.

The objective of this 2-year field study was to evaluate the effects of drip irrigation with urban wastewaters reclaimed using primary (filtration) and secondary (filtration and aeration) processes on red cabbage growth and fresh yield, heavy metal content, water use and efficiency and soil chemical properties. Filtered wastewater (WW1), filtered and aerated wastewater (WW2), freshwater and filtered wastewater mix (1:1 by volume) (WW3) and freshwater (FW) were investigated as irrigation water treatments. Crop evapotranspiration decreased significantly, while water use efficiency increased under wastewater treatments compared to FW. WW1 treatment had the lowest value (474.2 mm), while FW treatments had the highest value (556.7 mm). The highest water use efficiency was found in the WW1 treatment as 8.41 kg m(-3), and there was a twofold increase with regard to the FW. Wastewater irrigation increased soil fertility and therefore red cabbage yield. WW2 treatment produced the highest total fresh yield (40.02 Mg ha(-1)). However, wastewater irrigation increased the heavy metal content in crops and soil. Cd content in red cabbage heads was above the safe limit, and WW1 treatment had the highest value (0.168 mg kg(-1)). WW3 treatment among wastewater treatments is less risky in terms of soil and crop heavy metal pollution and faecal coliform contamination. Therefore, WW3 wastewater irrigation for red cabbage could be recommended for higher yield and water efficiency with regard to freshwater irrigation.

Farmers are being encouraged to represent the conjunctive use of fresh water (FW) and saline water (SW) irrigation for the future agriculture in the coastal saline prone areas of Bangladesh where the scarcity of FW. Therefore, the effects of fresh and saline water irrigation for maize was performed on the crop performances, water use, water productivity (WP), soil salinity and scope for maize cultivation in coastal areas. The experiment was carried out at farmers’ field at two locations with six irrigation treatments and replicated thrice during 2016–2017 and 2017–2018. Results showed that the effect of FW (0.5 ≤ salinity ≤ 1.5 dS/m) at early growth stages and SW (1.5 ≤ salinity ≤ 5 dS/m) at later growth stages had insignificant difference compared to the treatment of FW irrigation. Yield slightly increased with increased number of irrigations but there was no significant differences among the treatment. WP significantly affected by irrigation frequency in both locations, decreasing greatly with increasing amount. The more changes in soil water occurred at upper layer than lower depth of soil profiles. The highest changes soil salinity (ECe) occurred at mid-February of the crop growing season compared to the beginning and later growth stages of maize in 60 cm soil profiles. The technique of fresh and saline water irrigation at different growth stages of maize in coastal regions could be an alternative irrigation scheduled and method for increasing yield and WP through establishment of maize compared to no crops at fallow lands during rabi (dry) season in the salt affected areas of Bangladesh.

American Institute of Mining, Metallurgical and Petroleum Engineers, Inc. This paper was prepared for the 42nd Annual Fall Meeting of the Society of Petroleum Engineers of AIME, to be held in Houston, Tex., Oct. 1–4, 1967. Permission to copy is restricted to an abstract of not more than 300 words. Illustrations may not be copied. The abstract should contain conspicuous acknowledgment of where and by whom the paper is presented. Publication elsewhere after publication in the JOURNAL OF PETROLEUM TECHNOLOGY or the SOCIETY OF PETROLEUM ENGINEERS JOURNAL is usually granted upon request to the Editor of the appropriate journal provided agreement to give proper credit is made. Discussion of this paper is invited. Three copies of any discussion should be sent to the Society of Petroleum Engineers office. Such discussion may be presented at the above meeting and, with the paper, may be considered for publication in one of the two SPE magazines. Abstract Numerous hot water or steam injection projects have been restricted or prevented entirely by a lack of suitable fresh water. Fresh water supplies may become even more restricted in the future. These studies, which are continuing, should provide some of the water treatment answers necessary to permit use of waters and brines now considered unsuitable as feed to conventional heaters and steam generators. The pilot steam generator used in this research was designed to provide steam at up to 600 degrees F with heat transfer of at least 15,000 BTU's per ft(2) per hour. All steam is confined to 1/2 or 3/8 inch tubes. Areas of study include corrosion and scale deposition as well as treating processes for their control. The first studies were to determine the effect of an EDTA compound on corrosion in a system of 500 degrees F 80% steam. The presence of the EDTA compound, in any concentration, increased corrosion rates. Above 25 ppm EDTA the attack became severe with pitting at points of turbulence. The effect was the same whether the compound was in the free or chelated form. If EDTA is to be used 10 ppm active ingredient is considered as the safe upper limit. The present work is concerned with investigating various processes and compounds for prevention of scale deposition. Several high molecular weight polyacrylates have been found to inhibit deposition of calcium sulfate at 350 degrees F and 70% quality. Continuing work along this line is expected to allow the use of many oil field waters as feed to steam generators. Introduction Thermal recovery projects, notably hot water and steam injection, to stimulate the production of oil have emphasized a general lack of brackish water treating procedures for elevated temperatures. There has been extensive research on the problems associated with desalting of brackish and ocean waters. Some of this information is pertinent to the problems associated with thermal recovery. There are, however, three significant differences. First, even in the distillation processes desalting temperatures rarely exceed 250 degrees F while 500 degrees F and higher are common in thermal recovery.

Southwestern Energy (SWN) is committed to offsetting our fresh water footprint by reducing fresh water use and replenishing any fresh water that is used, barrel for barrel, through conservation projects, i.e., "Fresh water Neutral". In 2013, thecompany launched the Energy Conserving Water (ECH2O®) initiative with the goal of becoming fresh water neutral in all operations within three years. SWN achieved this status in 2016 within each of the operating divisions across the company, thus meeting the program objective. This paper presents the challenges encountered and offers lessons learned. The first step in the program was to create a small corporate team to investigate all aspects of the operational water life cycle, seeking to optimize fresh water use at similar economic returns compared with other projects. Successfully refining the approach to water management involved several key elements: 1) commitment from company leadership and support across all operations, 2) operational goals to progress the program, 3) accounting for all water used, 4) modification of completion designs, 5) increased use of alternative, non-fresh water, and 6) supporting research in groundwater protection and water treatment technologies. Even though the process of optimizing water management aids in reducing fresh water needs, there continues to be a critical demand for the use of fresh water in operations. To offset this use, SWN has participated in conservation projects located in each operational area. The conservation projects are selected for the fresh water benefit they generate for the surrounding environment. Becomingfresh water neutral in each operational division required several changes and improvements in everyday work practices. Over time, it also changed the mindset of water management across the company. Today fresh water use is viewed differently and there is an impetus to use alternative sources whenever economically and operationally feasible. Also, the conservation projects SWN has completed have created a sense of pride in our company's environmental approach and strengthened bonds with the communities where we work. The continuing challenge is to remain fresh water neutral, while dealing with short-term changes that occur in operational pace and activity levels.

Quantifying inorganic carbon fluxes to and from fresh waters is essential as part of understanding ecosystem functioning, potable water quality, and the amount of carbon exported to both the atmosphere and the oceans. Despite this, evidence of how anthropogenic withdrawals of fresh water perturb both land-fresh water-ocean and fresh water-atmosphere carbon fluxes is limited. Using the United States (US) as an exemplar, here we quantify for the first time the impact that both fresh surface water and fresh groundwater withdrawals by major water use sectors can have on land-fresh water-ocean and fresh water-atmosphere inorganic carbon fluxes. Fresh surface water withdrawals across the US during 2015 resulted in an estimated median gross dissolved inorganic carbon (DIC) retention flux of 8.5 (interquartile range: 6.5-11.3) Tg C yr-1, equivalent to 29% of the total export of DIC to the oceans from US rivers. The median gross retention flux due to fresh groundwater withdrawals was estimated to be 6.5 (interquartile range: 4.9-8.7) Tg C yr-1, over eight times the magnitude of the DIC flux to the oceans by subterranean groundwater discharging from the US. The median emission of CO2 from fresh waters to the atmosphere due to degassing of CO2 supersaturated groundwater following withdrawal was estimated to be 2.2 Tg CO2 yr-1 (interquartile range 1.2-4.3), 30% larger than previous estimates. Irrigation and public supply water use sectors contributed 70% and 19% of this total CO2 emission, respectively. County-level CO2 emissions from degassing groundwater following withdrawal exceeded the total county-level CO2 emissions from major emitting facilities across 1,391 counties, many of which were within Western and Midwestern states. This highlighted importance of freshwater withdrawals for DIC fluxes and CO2 emissions has implications for the accurate development of carbon budgets both across the United States, and for other regions around the world that are associated with significant freshwater withdrawals.

Appropriate use of marginal-quality waters coupled with crop rotation(s) and management interventions on saline-sodic soils have the potential to transform such water and soil resources from environmental burdens into economic assets. Several long-term field studies in the Indus basin of Pakistan were carried out to evaluate different irrigation and soil management options of using saline-sodic waters on saline-sodic soils for reclamation in a rice-wheat production system. The effect of different amendments like gypsum (gypsum requirement on water RSC basis and on soil SAR basis) and farm manure along with conjunctive use of fresh and saline-sodic waters for irrigating rice and wheat crops was evaluated. The effects of applied amendments were evaluated in terms of change in the physical and chemical properties of soils, yield-based crop growth response and economic implications. The results showed significant improvement in physical and chemical properties of soils with good yields of crops with the application of amendments specially gypsum and farm manure along with conjunctive use of fresh and saline-sodic waters. Salt removal (kg ha−1) was the highest with the application of two pore volume (PV) water. In general, it was concluded that after the application of four irrigations of different PV, highest leaching fraction removed maximum salts from loamy sand soil. Salt removal remained the highest with first two irrigations and then decreased subsequently. Overall, the greatest net benefit was obtained from gypsum plus cyclic use of saline-sodic and fresh waters. It was found that the farmers’ management skills were crucial in the overall success to improve crop yields during reclamation of saline-sodic soils. Based on the results, we propose that saline-sodic water could be used to reclaim saline-sodic soils by using a rice-wheat rotation and a site-specific combination of soil amendments and water application strategies.

Pseudo-castration effects of social isolation on extinction of a taste aversion

Species sensitivity distributions (SSDs) are commonly used in risk assessment and in setting water quality guidelines, yet their predictions have not been validated against loss of species with increasing pollutant concentrations in nature. We used a rapid toxicity testing method to determine the acute salinity tolerance (72 h LC50 values (concentration of salinity lethal to 50% of individuals)) of 110 macroinvertebrate taxa from the southern Murray–Darling Basin in central Victoria, Australia, and construct an SSD. This SSD was compared with loss of riverine macro invertebrates species from increasing salinity in Victoria. Macroinvertebrate species richness per individual sample, when salinity was <9.9 mS·cm–1, was invariant of salinity. However, when species richness was calculated across multiple samples above about 0.3–0.5 mS·cm–1, it declined with increasing salinity. This decline was predicted from the SSD after application of a variable safety factor calculated from an exponential or quadratic equation. Our findings confirm that SSDs can predict the loss of freshwater macroinvertebrate species from increases in salinity. This suggests that SSDs may be useful more generally for other aquatic organisms, other stressors, and toxicants.