The necessity to saline and sodic waters is sometimes used for irrigating agricultural activities under certain circumstances, but it is important to note that the use of these waters comes with specific consideration...The necessity to saline and sodic waters is sometimes used for irrigating agricultural activities under certain circumstances, but it is important to note that the use of these waters comes with specific considerations and limitations. One way to decrease undesirable effects of sodic waters on the physical and chemical properties of soils is to apply organic and chemical amendments within the soil. This study aimed to assess the effectiveness of saline water on soil acidity, alkalinity and nutrients leaching in sandy loamy soil at Bella flower farm, in Rwamagana District, Rwanda. The water used was from the Muhazi Lake which is classified as Class I (Saline water quality). Column leaching experiments using treated soils were then conducted under saturated conditions. The soil under experimental was first analyzed for its textural classification, soil properties and is classified as sandy loamy soil. The t-test was taken at 1%, 5% and 10% levels of statistical significance compared to control soil. The results indicated that the application of saline water to soils caused an increase in some soil nutrients like increase of Phosphorus (P), Potassium (K<sup>+</sup>), Magnesium (Mg2<sup>+</sup>), Sulphur (S), CN ratio and Sodium (Na<sup>+</sup>) and decreased soil texture, physical and chemical properties and remained soil nutrients. Consequently, the intensive addition of saline water leachates to soil in PVC pipes led to decreased of soil EC through leaching and a raiser Soluble Sodium Percentage (SSP). The rate of saline water application affected the increase accumulation of SAR and Na% in the top soil layers. The study indicated that saline water is an inefficient amendment for sandy soil with saline water irrigation. The study recommends further studies with similar topic with saline water irrigation, as it accentuated the alkalinity levels.展开更多
High-entropy materials(HEMs),which are newly manufactured compounds that contain five or more metal cations,can be a platform with desired properties,including improved electrocatalytic performance owing to the inhere...High-entropy materials(HEMs),which are newly manufactured compounds that contain five or more metal cations,can be a platform with desired properties,including improved electrocatalytic performance owing to the inherent complexity.Here,a strain engineering methodology is proposed to design transition-metal-based HEM by Li manipulation(LiTM)with tunable lattice strain,thus tailoring the electronic structure and boosting electrocatalytic performance.As confirmed by the experiments and calculation results,tensile strain in the LiTM after Li manipulation can optimize the d-band center and increase the electrical conductivity.Accordingly,the asprepared LiTM-25 demonstrates optimized oxygen evolution reaction and hydrogen evolution reaction activity in alkaline saline water,requiring ultralow overpotentials of 265 and 42 mV at 10 mA cm−2,respectively.More strikingly,LiTM-25 retains 94.6%activity after 80 h of a durability test when assembled as an anion-exchange membrane water electrolyzer.Finally,in order to show the general efficacy of strain engineering,we incorporate Li into electrocatalysts with higher entropies as well.展开更多
Field experiments were conducted in 2008 and 2009 to study the effects of deficit irrigation with saline water on spring wheat growth and yield in an arid region of Northwest China. Nine treatments included three sali...Field experiments were conducted in 2008 and 2009 to study the effects of deficit irrigation with saline water on spring wheat growth and yield in an arid region of Northwest China. Nine treatments included three salinity levels sl, s2 and s3 (0.65, 3.2, and 6.1 dS/m) in combination with three water levels wl, w2 and w3 (375, 300, and 225 mm). In 2008, for most treatments, deficit irrigation showed adverse effects on wheat growth; meanwhile, the effect of saline irrigation was not apparent. In 2009, growth parameters of wl treatments were not always optimal under saline irrigation. At 3.2 and 6.1 dS/m in 2008, the highest yield was obtained by wl treatments, however, in 2009, the weight of 1,000 grains and wheat yield both followed the order w2 〉 wl 〉 w3. In this study, spring wheat was sensitive to water deficit, especially at the booting to grain-filling stages, but was not significantly affected by saline irrigation and the combination of the two factors. The results demonstrated that 300-mm irrigation water with a salinity of less than 3.2 dS/m is suitable for wheat fields in the study area.展开更多
Furrow irrigation when combined with plastic mulch on ridge is one of the current uppermost wa- ter-saving irrigation technologies for arid regions. The present paper studies the dynamics of soil water-salt trans- por...Furrow irrigation when combined with plastic mulch on ridge is one of the current uppermost wa- ter-saving irrigation technologies for arid regions. The present paper studies the dynamics of soil water-salt trans- portation and its spatial distribution characteristics under irrigation with saline water in a maize field experiment. The mathematical relationships for soil salinity, irrigation amount and water salinity are also established to evaluate the contribution of the irrigation amount and the salinity of saline water to soil salt accumulation. The result showed that irrigation with water of high salinity could effectively increase soil water content, but the increment is limited com- paring with the influence from irrigation amount. The soil water content in furrows was higher than that in ridges at the same soil layers, with increments of 12.87% and 13.70% for MMF9 (the treatment with the highest water salinity and the largest amount of irrigation water) and MMF1 (the treatment with the lowest water salinity and the least amount of irrigation water) on 27 June, respectively. The increment for MMF9 was gradually reduced while that for MMF1 increased along with growth stages, the values for 17 August being 2.40% and 19.92%, respectively. Soil water content in the ridge for MMF9 reduced gradually from the surface layer to deeper layers while the surface soil water content for MMF1 was smaller than the contents below 20 cm at the early growing stage. Soil salinities for the treatments with the same amount of irrigation water but different water salinity increased with the water salinity. When water salinity was 6.04 dS/m, the less water resulted in more salt accumulation in topsoil and less in deep layers. When water salinity was 2.89 dS/m, however, the less water resulted in less salt accumulation in topsoil and salinity remained basically stable in deep layers. The salt accumulation in the ridge surface was much smaller than that in the furrow bottom under this technology, which was quite different from traditional furrow irrigation. The soil salinities for MMF7, MMF8 and MMF9 in the ridge surface were 0.191, 0.355 and 0.427 dS/m, respectively, whereas those in the furrow bottom were 0.316, 0.521 and 0.631 dS/m, respectively. The result of correlation analysis indicated that compared with irrigation amount, the irrigation water salinity was still the main factor influ- encing soil salinity in furrow irrigation with plastic mulch on ridge.展开更多
Hydrogen generation from water splitting is of great prospect for the sustainable energy conversion.However,it is still challenging to explore stable and high-performance electrocatalysts toward hydrogen evolution rea...Hydrogen generation from water splitting is of great prospect for the sustainable energy conversion.However,it is still challenging to explore stable and high-performance electrocatalysts toward hydrogen evolution reaction(HER)from saline water such as seawater due to the chloride corrosion.Herein,we developed a self-supported heterogeneous bimetallic phosphide(Ni_(2)P-FeP)array electrode that possesses excellent HER performance in alkaline saline water with an overpotential of 89 mV at 10 mA·cm^(−2)and long-term stability over 90 h at 200 mA·cm^(−2).The analysis showed that the heterostructure between the interfaces of Ni_(2)P-FeP plays a pivotal role in promoting the activity of catalyst.Moreover,the bimetallic phosphide nanoarrays can be employed as a shield for chlorine-corrosion resistance in the saline water,ensuring the long-term durability of hydrogen generation.When employed for alkaline saline water electrolysis,a current density of 100 mA·cm^(−2)is achieved at cell voltage of 1.68 V.This work presents an effective approach for the fabrication of high-performance electrode for HER in alkaline saline environments.展开更多
The properties of salinity in the South China Sea(SCS),a significant marginal sea connecting the Pacific and Indian Oceans,are greatly influenced by the transport of fresh water flux between the two oceans.However,the...The properties of salinity in the South China Sea(SCS),a significant marginal sea connecting the Pacific and Indian Oceans,are greatly influenced by the transport of fresh water flux between the two oceans.However,the long-term changes in the intermediate water in the SCS have not been thoroughly studied due to limited data,particularly in relation to its thermodynamic variations.This study utilized reanalysis data products to identify a 60-year trend of freshening in the intermediate waters of the northern South China Sea(NSCS),accompanied by an expansion of low-salinity water.The study also constructed salinity budget terms,including advection and entrainment processes,and conducted an analysis of the salinity budget to understand the impacts of external and internal dynamic processes on the freshening trend of the intermediate water in the NSCS.The analysis revealed that the freshening in the northwest Pacific Ocean and the intensification of intrusion through the Luzon Strait at intermediate levels are the primary drivers of the salinity changes in the NSCS.Additionally,a weakened trend in the intensity of vertical entrainment also contributes to the freshening in the NSCS.This study offers new insights into the understanding of regional deep sea changes in response to variations in both thermodynamics and oceanic dynamic processes.展开更多
Appropriate application of water-salt-crop function model can optimize agricultural water management in regions with declining water supply,such as the Hetao district.Appropriate use of saline water is also based on t...Appropriate application of water-salt-crop function model can optimize agricultural water management in regions with declining water supply,such as the Hetao district.Appropriate use of saline water is also based on the effects of irrigation water demand and water quality on crop growth quantitatively.Therefore,oil sunflower growth testing under both water and salt stress was completed from 2013 to 2014.Water salinity levels at 1.7 ds/m,4 ds/m,6 ds/m and 8 ds/m were used in the experiments.Two water deficit levels were reported,60%and 80%of the irrigation quota,which were considered moderate and mild deficit levels,respectively.All treatments were applied in planting the oil sunflower in critical growing periods,namely,floral initiation,anthesis and maturity.Linear,Cobb-Douglas,quadratic and transcendental function models were used to simulate the relative yield,evapotranspiration(ET)and electrical conductivity(EC).The predictive ability and sensitivity of each model were then evaluated.Compared with salt stress,water stress exerted a more significant effect on the oil sunflower yield;the water parameters(a1 and a3)were most sensitive in the water-salt-crop function model.Oil sunflower was most sensitive to water and salt stress during anthesis.The transcendental function generally showed a relatively high sensitivity coefficient and a relatively small statistical error.Therefore,the transcendental function is the most appropriate model for simulating and predicting the yield of oil sunflower irrigated with saline water.Applying the water-salt-crop function model in planting of oil sunflower can help in the development and utilization of saline water in the Hetao district.展开更多
Water insufficiency is the hampering feature of crop sustainability,especially in arid and semi-arid regions.So,the effectual usage of all water resources especially underground brackish water represents the core prio...Water insufficiency is the hampering feature of crop sustainability,especially in arid and semi-arid regions.So,the effectual usage of all water resources especially underground brackish water represents the core priority in Saudi Arabia.The present study aimed to recognize the influence of different types of water irrigation(tap water as a control,salinized well water,and magnetized salinized well water)with or without soil amendments(soil without any amendment as a control,peat-moss,ferrous sulfate,and peat-moss plus ferrous sulfate)on petunia plant growth and flowering as well as ion content.Irrigating Petunia plants with saline well water adversely affected growth and flowering as compared to tap water and magnetized saline well water.Additionally,plants irrigated with magnetized water showed a significant enhancement in all the studied vegetative and flowering growth parameters as compared to those irrigated with salinized well water.Furthermore,mineral contents and survival of Petunia plants irrigated with magnetized well water were higher than those irrigated with tap water.Irrigation with magnetized well water significantly reduced levels of Na+and Cl−ions in leaves of Petunia plants indicating the role of magnetization in alleviating harmful effects of salinity.In conclusion,we recommend the utilization of magnetized saline well water for irrigating Petunia plants either alone or in combination with soil amendments(peat moss plus ferrous sulfate).展开更多
Laboratory and field experiments were conducted to investigate the effects of water application intensity(WAI) on soil salinity management and the growth of Festuca arundinacea(festuca) under three stages of water...Laboratory and field experiments were conducted to investigate the effects of water application intensity(WAI) on soil salinity management and the growth of Festuca arundinacea(festuca) under three stages of water and salt management strategies using microsprinkler irrigation in Hebei Province, North China. The soil water content(è) and salinity of homogeneous coastal saline soils were evaluated under different water application intensities in the laboratory experiment. The results indicated that the WAI of microsprinkler irrigation influenced the è, electrical conductivity(ECe) and p H of saline soils. As the WAI increased, the average values of è and ECe in the 0–40 cm profile also increased, while their average values in the 40–60 cm profile decreased. The p H value also slightly decreased as depth increased, but no significant differences were observed between the different treatments. The time periods of the water redistribution treatments had no obvious effects. Based on the results for è, ECe and p H, a smaller WAI was more desirable. The field experiment was conducted after being considered the results of the technical parameter experiment and evaporation, wind and leaching duration. The field experiment included three stages of water and salt regulation, based on three soil matric potentials(SMP), in which the SMP at a 20-cm depth below the surface was used to trigger irrigation. The results showed that the microsprinkler irrigation created an appropriate environment for festuca growth through the three stages of water and salt regulation. The low-salinity conditions that occurred at 0–10 cm depth during the first stage(-5 k Pa) continued to expand through the next two stages. The average p H value was less than 8.5. The tiller number of festuca increased as SMP decreased from the first stage to the third stage. After the three stages of water and salt regulation, the highly saline soil gradually changed to a low-saline soil. Overall, based on the salt desalinization, the microsprinkler irrigation and three stages of water and salt regulation could be successfully used to cultivate plants for the reclamation of coastal saline land in North China.展开更多
Combining low salinity water (LSW) with surfactants has an enormous potential for enhancing oil recovery processes. However, there is no consensus about the mechanisms involved, in addition to the fact that several st...Combining low salinity water (LSW) with surfactants has an enormous potential for enhancing oil recovery processes. However, there is no consensus about the mechanisms involved, in addition to the fact that several studies have been conducted in model systems, while experiments with rocks and reservoir fluids are scarce. This study presents a core-flooding experiment of LSW injection, with and without surfactant, using the core and heavy oil samples obtained from a sandstone reservoir in southeastern Mexico. The effluents and the crude oil obtained at each stage were analyzed. The study was complemented by tomographic analysis. The results revealed that LSW injection and hybrid process with surfactants obtained an increase of 11.4 percentage points in recovery factor. Various phenomena were caused by LSW flooding, such as changes in wettability and pH, ion exchange, mineral dissolution, detachment of fines and modification of the hydrocarbon profile. In the surfactant flooding, the reduction of interfacial tension and alteration of wettability were the main mechanisms involved. The findings of this work also showed that the conditions believed to be necessary for enhanced oil recovery with LSW, such as the presence of kaolinite or high acid number oil, are not relevant.展开更多
In the dominant winter wheat (WW)-summer maize (SM) double cropping system in the low plain located in the North China, limited access to fresh water, especially during dry season, constitutes a major obstacle to ...In the dominant winter wheat (WW)-summer maize (SM) double cropping system in the low plain located in the North China, limited access to fresh water, especially during dry season, constitutes a major obstacle to realize high crop productivity. Using the vast water resources of the saline upper aquifer for irrigation during WW jointing stage, may help to bridge the peak of dry season and relieve the tight water situation in the region. A field experiment was conducted during 2009-2012 to investigate the effects of saline irrigation during WW jointing stage on soil salt accumulation and productivity of WW and SM. The experiment treatments comprised no irrigation (T1), fresh water irrigation (T2), slightly saline water irrigation (T3:2.8 dS m-l), and strongly saline water irrigation (T4:8.2 dS m-1) at WW jointing stage. With regard to WW yields and aggregated annual WW-SM yields, clear benefits of saline water irrigation (T3 & T4) compared to no irrigation (T1), as well as insignificant yield losses compared to fresh water irrigation (T2) occurred in all three experiment years. However, the increased soil salinity in eady SM season in consequence of saline irrigation exerted a negative effect on SM photosynthesis and final yield in two of three experiment years. To avoid the negative aftereffects of saline irrigation, sufficient fresh water irrigation during SM sowing phase (i.e., increase from 60 to 90 mm) is recommended to guarantee good growth conditions during the sensitive early growing period of SM. The risk of long-term accumulation of salts as a result of saline irrigation during the peak of dry season is considered low, due to deep leaching of salts during regularly occurring wet years, as demonstrated in the 2012 experiment year. Thus, applying saline water irrigation at jointing stage of WW and fresh water at sowing of SM is most promising to realize high yield and fresh irrigation water saving.展开更多
In arid and semi-arid regions, freshwater scarcity and high water salinity are serious and chronic problems for crop production and sustainable agriculture development. We conducted a field experiment to evaluate the ...In arid and semi-arid regions, freshwater scarcity and high water salinity are serious and chronic problems for crop production and sustainable agriculture development. We conducted a field experiment to evaluate the effect of irrigation water salinity and nitrogen(N) application rate on soil salinity and cotton yield under drip irrigation during the 2011 and 2012 growing seasons. The experimental design was a 3×4 factorial with three irrigation water salinity levels(0.35, 4.61 and 8.04 dS/m) and four N application rates(0, 240, 360 and 480 kg N/hm2). Results showed that soil water content increased as the salinity of the irrigation water increased, but decreased as the N application rate increased. Soil salinity increased as the salinity of the irrigation water increased. Specifically, soil salinity measured in 1:5 soil:water extracts was 218% higher in the 4.61 dS/m treatment and 347% higher in the 8.04 dS/m treatment than in the 0.35 dS/m treatment. Nitrogen fertilizer application had relatively little effect on soil salinity, increasing salinity by only 3%–9% compared with the unfertilized treatment. Cotton biomass, cotton yield and evapotranspiration(ET) decreased significantly in both years as the salinity of irrigation water increased, and increased as the N application rate increased regardless of irrigation water salinity; however, the positive effects of N application were reduced when the salinity of the irrigation water was 8.04 dS/m. Water use efficiency(WUE) was significantly higher by 11% in the 0.35 dS/m treatment than in the 8.04 dS/m treatment. There was no significant difference in WUE between the 0.35 dS/m treatment and the 4.61 dS/m treatment. The WUE was also significantly affected by the N application rate. The WUE was highest in the 480 kg N/hm2 treatment, being 31% higher than that in the 0 kg N/hm2 treatment and 12% higher than that in the 240 kg N/hm2 treatment. There was no significant difference between the 360 and 480 kg N/hm2 treatments. The N use efficiency(NUE) was significantly lower in the 8.04 dS/m treatment than in either the 4.61 dS/m or the 0.35 dS/m treatment. There was no significant difference in NUE between the latter two treatments. These results suggest that irrigation water with salinity 〈4.61 dS/m does not have an obvious negative effect on cotton production, WUE or NUE under the experimental conditions. Application of N fertilizer(0–360 kg N/hm2) could alleviate salt damage, promote cotton growth, and increase both cotton yield and water use efficiency.展开更多
Use of saline water in irrigated agriculture has become an important means for alleviating water scarcity in arid and semi-arid regions. The objective of this field experiment was to evaluate the effects of irrigation...Use of saline water in irrigated agriculture has become an important means for alleviating water scarcity in arid and semi-arid regions. The objective of this field experiment was to evaluate the effects of irrigation water salinity and N fertilization on soil physicochemical and biological properties related to nitrification and denitrification. A 3×2 factorial design was used with three levels of irrigation water salinity(0.35, 4.61 and 8.04 d S m-1) and two N rates(0 and 360 kg N ha^(-1)). The results indicated that irrigation water salinity and N fertilization had significant effects on many soil physicochemical properties including water content, salinity, p H, NH_4-N concentration, and NO_3-N concentration. The abundance(i.e., gene copy number) of ammonia-oxidizing archaea(AOA) was greater than that of ammonia-oxidizing bacteria(AOB) in all treatments. Irrigation water salinity had no significant effect on the abundance of AOA or AOB in unfertilized plots. However, saline irrigation water(i.e., the 4.61 and 8.04 d S m-1 treatments) reduced AOA abundance, AOB abundance and potential nitrification rate in N fertilized plots. Regardless of N application rate, saline irrigation water increased urease activity but reduced the activities of both nitrate reductase and nitrite reductase. Irrigation with saline irrigation water significantly reduced cotton biomass, N uptake and yield. Nitrogen application exacerbated the negative effect of saline water. These results suggest that brackish water and saline water irrigation could significantly reduce both the abundance of ammonia oxidizers and potential nitrification rates. The AOA may play a more important role than AOB in nitrification in desert soil.展开更多
Saline groundwater is widely distributed in Heilonggang region. While deep confined water is being mined, saline water has not been used in most part of the region. Extension of saline water irrigation is of signific...Saline groundwater is widely distributed in Heilonggang region. While deep confined water is being mined, saline water has not been used in most part of the region. Extension of saline water irrigation is of significance to resolve water shortage, slow down environmental degradation and support the sustainable development of the local agriculture. Four key points are proposed to be managed by comprehensive measures: (1) adapting salt resistant ability; (2) reducing salt input; (3) decreasing soil surface evaporation and salt accumulation in the root zone, and (4) washing away salt from the root zone. Experiments and farming practices demonstrated that brackish water with TDS (total dissolved solids) of 2-5 g/l can be used for crop irrigation. For example, winter wheat can be sustainably irrigated by brackish water with a water limitation of 120 mm every year. Irrigation in combination with different comprehensive measures can increase the efficiency of saline water irrigation.展开更多
In order to solve water resources problems in the North China Plain, this paper explored human-nature compound water circulation system from three aspects including urban flood control, surface drainage and saline wat...In order to solve water resources problems in the North China Plain, this paper explored human-nature compound water circulation system from three aspects including urban flood control, surface drainage and saline water in the central and eastern of the North China Plain. Results show that:(1) The technical methods have achieved zero increase in rainwater runoff in urban areas,(2) surface drainage depletion problems can be solved through abandoned water and river water separation method,(3) and technical method through promoting rainwater infiltration would be used to solve problem of saline water in the central and eastern parts. This research provides a new perspective to the ultimate solutions to water resources problems in the North China Plain, and a fresh research direction for the development of hydro-geological science.展开更多
An experimental study was performed to investigate the impact of low salinity water on wettability alteration in carbonate core samples from southern Iranian reservoirs by spontaneous imbibition. In this paper, the ef...An experimental study was performed to investigate the impact of low salinity water on wettability alteration in carbonate core samples from southern Iranian reservoirs by spontaneous imbibition. In this paper, the effect of temperature, salinity,permeability and connate water were investigated by comparing the produced hydrocarbon curves. Contact angle measurements were taken to confirm the alteration of surface wettability of porous media. Oil recovery was enhanced by increasing the dilution ratio of sea water, and there existed an optimum dilution ratio at which the highest oil recovery was achieved. In addition, temperature had a very significant impact on oil recovery from carbonate rocks. Furthermore, oil recovery from a spontaneous imbibition process was directly proportional to the permeability of the core samples. The presence of connate water saturation inside the porous media facilitated oil production significantly. Also, the oil recovery from porous media was highly dependent on ion repulsion/attraction activity of the rock surface which directly impacts on the wettability conditions. Finally, the highest ion attraction percentage was measured for sodium while there was no significant change in pH for all experiments.展开更多
In this study, nineteen brine samples from the Qarhan Salt Lake(QSL) in western China were collected and analyzed for boron(B) and chlorine(Cl) concentrations, total dissolved solids(TDS), pH values and stable B isoto...In this study, nineteen brine samples from the Qarhan Salt Lake(QSL) in western China were collected and analyzed for boron(B) and chlorine(Cl) concentrations, total dissolved solids(TDS), pH values and stable B isotopic compositions. The B concentrations and δ^(11) B values of brines in the QSL range from 51.6 mg/L to138.4 mg/L, and from +9.32& to +13.08&, respectively. By comparison of B concentrations and TDS of brines in QSL with evaporation paths of brackish water, we found that B enrichment of brines primarily results from strong evaporation and concentration of Qarhan lake water. Combining with comparisons of B concentrations, TDS, p H values and δ^(11) B values of brines, previously elemental ratios(K/Cl, Mg/Cl, Ca/Cl, B/Cl) and δ^(11) B values of halite from a sediment core(ISL1 A), we observe good correlations between B concentrations and TDS, TDS and pH values, pH and δ^(11) B values of brines, which demonstrate that higher B concentrations and more positive δ^(11) B values of halite indicate higher salinity of the Qarhan paleolake water as well as drier paleoclimatic conditions. Based on this interpretation of the δ^(11) B values of halite in core ISL1 A, higher salinity of the Qarhan paleolake occurred during two intervals, around 46-34 ka and26-9 ka, which are almost coincident with the upper and lower halite-dominated salt layers in core ISL1 A,drier climate phases documented from the δ^(18) O record of carbonate in core ISL1 A and the paleomoisture record in monsoonal central Asia, and a higher solar insolation at 30°N. These results demonstrate that the δ^(11) B values of halite in the arid Qaidam Basin could be regarded as a new proxy for reconstructing the salinity record of paleolake water as well as paleoclimate conditions.展开更多
Yellow River water transfer for Tianjin is important in solving the water shortage in Tianjin, which facilitate economic development and social progress for many years. Fresh water drawn from Yellow River( i. e., Yin...Yellow River water transfer for Tianjin is important in solving the water shortage in Tianjin, which facilitate economic development and social progress for many years. Fresh water drawn from Yellow River( i. e., Yin-Huang water) becomes saltier and saltier when being stored in the Bei-Da-Gang reservoir. We qualitatively analyze the water salinization mechanism based on mass transfer theory. The main factors are salinity transfer of saline soil, evaporation concentrating, and the agitation of wind. A simulative experimental pond and an evaporation pond were built beside the Bei-Da-Gang reservoir to quantitatively investigate the water salinization based on water and solute balance in the simulative pond. 80% of increased [Cl^-] is due to the salinity transfer of the saline soil and the other 20% is due to evaporation concentrating, so the former is the most important factor. We found that the salinization of Yin-Huang water can be described with a zero-dimension linear model.展开更多
Groundwater-fed lakes are essential for the ecology in arid and semiarid regions.As a typical arid region,the Badain Jaran Desert (BJD) is famous in the world for the presence of a large number of groundwater-fed sa...Groundwater-fed lakes are essential for the ecology in arid and semiarid regions.As a typical arid region,the Badain Jaran Desert (BJD) is famous in the world for the presence of a large number of groundwater-fed saline lakes among the mega dunes.Based on the up to date geological surveys and observations,this study analyzed the groundwater contributions in water-salt balances of the lakes in the desert.We found different types of springs,including the sublacustrine springs that indicate an upward flow of groundwater under the lakebed.A simplified water balance model was developed to analyze the seasonal variations of water level in the Sumu Barun Jaran Lake,which revealed an approximately steady groundwater discharge in the lake and explained why the amplitude of seasonal changes in lake level is less than 0.5 m.In addition,a salt balance model was developed to evaluate the salt accumulations in the groundwater-fed lakes.The relative salt accumulation time is 800–7,000 years in typical saline lakes,which were estimated from the concentration of Cl-,indicating a long history evolution for the lakes in the BJD.Further researches are recommended to provide comprehensive investigations on the interactions between the lakes and groundwater in the BJD.展开更多
文摘The necessity to saline and sodic waters is sometimes used for irrigating agricultural activities under certain circumstances, but it is important to note that the use of these waters comes with specific considerations and limitations. One way to decrease undesirable effects of sodic waters on the physical and chemical properties of soils is to apply organic and chemical amendments within the soil. This study aimed to assess the effectiveness of saline water on soil acidity, alkalinity and nutrients leaching in sandy loamy soil at Bella flower farm, in Rwamagana District, Rwanda. The water used was from the Muhazi Lake which is classified as Class I (Saline water quality). Column leaching experiments using treated soils were then conducted under saturated conditions. The soil under experimental was first analyzed for its textural classification, soil properties and is classified as sandy loamy soil. The t-test was taken at 1%, 5% and 10% levels of statistical significance compared to control soil. The results indicated that the application of saline water to soils caused an increase in some soil nutrients like increase of Phosphorus (P), Potassium (K<sup>+</sup>), Magnesium (Mg2<sup>+</sup>), Sulphur (S), CN ratio and Sodium (Na<sup>+</sup>) and decreased soil texture, physical and chemical properties and remained soil nutrients. Consequently, the intensive addition of saline water leachates to soil in PVC pipes led to decreased of soil EC through leaching and a raiser Soluble Sodium Percentage (SSP). The rate of saline water application affected the increase accumulation of SAR and Na% in the top soil layers. The study indicated that saline water is an inefficient amendment for sandy soil with saline water irrigation. The study recommends further studies with similar topic with saline water irrigation, as it accentuated the alkalinity levels.
基金support provided by the National Natural Science Foundation of China(Grant Nos.51972048,U23A20605)support provided by the Performance subsidy fund for Key Laboratory of Dielectric and Electrolyte Functional Material Hebei Province(Grant No.22567627H)the additional data in the revised manuscriptsupported by the National Key Research and Development Program of China(No.2022YFB3706300).
文摘High-entropy materials(HEMs),which are newly manufactured compounds that contain five or more metal cations,can be a platform with desired properties,including improved electrocatalytic performance owing to the inherent complexity.Here,a strain engineering methodology is proposed to design transition-metal-based HEM by Li manipulation(LiTM)with tunable lattice strain,thus tailoring the electronic structure and boosting electrocatalytic performance.As confirmed by the experiments and calculation results,tensile strain in the LiTM after Li manipulation can optimize the d-band center and increase the electrical conductivity.Accordingly,the asprepared LiTM-25 demonstrates optimized oxygen evolution reaction and hydrogen evolution reaction activity in alkaline saline water,requiring ultralow overpotentials of 265 and 42 mV at 10 mA cm−2,respectively.More strikingly,LiTM-25 retains 94.6%activity after 80 h of a durability test when assembled as an anion-exchange membrane water electrolyzer.Finally,in order to show the general efficacy of strain engineering,we incorporate Li into electrocatalysts with higher entropies as well.
基金supported by the National Basic Research Program of China (2011CB403406)the National Natural Science Foundation of China (51179166)the Youth Foundation of Taiyuan University of Technology (2012L077)
文摘Field experiments were conducted in 2008 and 2009 to study the effects of deficit irrigation with saline water on spring wheat growth and yield in an arid region of Northwest China. Nine treatments included three salinity levels sl, s2 and s3 (0.65, 3.2, and 6.1 dS/m) in combination with three water levels wl, w2 and w3 (375, 300, and 225 mm). In 2008, for most treatments, deficit irrigation showed adverse effects on wheat growth; meanwhile, the effect of saline irrigation was not apparent. In 2009, growth parameters of wl treatments were not always optimal under saline irrigation. At 3.2 and 6.1 dS/m in 2008, the highest yield was obtained by wl treatments, however, in 2009, the weight of 1,000 grains and wheat yield both followed the order w2 〉 wl 〉 w3. In this study, spring wheat was sensitive to water deficit, especially at the booting to grain-filling stages, but was not significantly affected by saline irrigation and the combination of the two factors. The results demonstrated that 300-mm irrigation water with a salinity of less than 3.2 dS/m is suitable for wheat fields in the study area.
基金supported by the National Natural Science Foundation of China (91025002,30970492)the National Key Technology R & D Program (2012BAC08B05)
文摘Furrow irrigation when combined with plastic mulch on ridge is one of the current uppermost wa- ter-saving irrigation technologies for arid regions. The present paper studies the dynamics of soil water-salt trans- portation and its spatial distribution characteristics under irrigation with saline water in a maize field experiment. The mathematical relationships for soil salinity, irrigation amount and water salinity are also established to evaluate the contribution of the irrigation amount and the salinity of saline water to soil salt accumulation. The result showed that irrigation with water of high salinity could effectively increase soil water content, but the increment is limited com- paring with the influence from irrigation amount. The soil water content in furrows was higher than that in ridges at the same soil layers, with increments of 12.87% and 13.70% for MMF9 (the treatment with the highest water salinity and the largest amount of irrigation water) and MMF1 (the treatment with the lowest water salinity and the least amount of irrigation water) on 27 June, respectively. The increment for MMF9 was gradually reduced while that for MMF1 increased along with growth stages, the values for 17 August being 2.40% and 19.92%, respectively. Soil water content in the ridge for MMF9 reduced gradually from the surface layer to deeper layers while the surface soil water content for MMF1 was smaller than the contents below 20 cm at the early growing stage. Soil salinities for the treatments with the same amount of irrigation water but different water salinity increased with the water salinity. When water salinity was 6.04 dS/m, the less water resulted in more salt accumulation in topsoil and less in deep layers. When water salinity was 2.89 dS/m, however, the less water resulted in less salt accumulation in topsoil and salinity remained basically stable in deep layers. The salt accumulation in the ridge surface was much smaller than that in the furrow bottom under this technology, which was quite different from traditional furrow irrigation. The soil salinities for MMF7, MMF8 and MMF9 in the ridge surface were 0.191, 0.355 and 0.427 dS/m, respectively, whereas those in the furrow bottom were 0.316, 0.521 and 0.631 dS/m, respectively. The result of correlation analysis indicated that compared with irrigation amount, the irrigation water salinity was still the main factor influ- encing soil salinity in furrow irrigation with plastic mulch on ridge.
基金supported by the National Natural Science Foundation(No.91963109)the Innovation Research Funds of Huazhong University of Science and Technology(No.2019kfyRCPY100).
文摘Hydrogen generation from water splitting is of great prospect for the sustainable energy conversion.However,it is still challenging to explore stable and high-performance electrocatalysts toward hydrogen evolution reaction(HER)from saline water such as seawater due to the chloride corrosion.Herein,we developed a self-supported heterogeneous bimetallic phosphide(Ni_(2)P-FeP)array electrode that possesses excellent HER performance in alkaline saline water with an overpotential of 89 mV at 10 mA·cm^(−2)and long-term stability over 90 h at 200 mA·cm^(−2).The analysis showed that the heterostructure between the interfaces of Ni_(2)P-FeP plays a pivotal role in promoting the activity of catalyst.Moreover,the bimetallic phosphide nanoarrays can be employed as a shield for chlorine-corrosion resistance in the saline water,ensuring the long-term durability of hydrogen generation.When employed for alkaline saline water electrolysis,a current density of 100 mA·cm^(−2)is achieved at cell voltage of 1.68 V.This work presents an effective approach for the fabrication of high-performance electrode for HER in alkaline saline environments.
基金National Natural Science Foundation of China(92158204,42076019)Innovation Group Project of the Southern Marine Science and Engineering Guangdong Laboratory(Zhuhai)(31020004)Open Project of the State Key Laboratory of Tropical Oceanography(LTOZZ2001)。
文摘The properties of salinity in the South China Sea(SCS),a significant marginal sea connecting the Pacific and Indian Oceans,are greatly influenced by the transport of fresh water flux between the two oceans.However,the long-term changes in the intermediate water in the SCS have not been thoroughly studied due to limited data,particularly in relation to its thermodynamic variations.This study utilized reanalysis data products to identify a 60-year trend of freshening in the intermediate waters of the northern South China Sea(NSCS),accompanied by an expansion of low-salinity water.The study also constructed salinity budget terms,including advection and entrainment processes,and conducted an analysis of the salinity budget to understand the impacts of external and internal dynamic processes on the freshening trend of the intermediate water in the NSCS.The analysis revealed that the freshening in the northwest Pacific Ocean and the intensification of intrusion through the Luzon Strait at intermediate levels are the primary drivers of the salinity changes in the NSCS.Additionally,a weakened trend in the intensity of vertical entrainment also contributes to the freshening in the NSCS.This study offers new insights into the understanding of regional deep sea changes in response to variations in both thermodynamics and oceanic dynamic processes.
文摘Appropriate application of water-salt-crop function model can optimize agricultural water management in regions with declining water supply,such as the Hetao district.Appropriate use of saline water is also based on the effects of irrigation water demand and water quality on crop growth quantitatively.Therefore,oil sunflower growth testing under both water and salt stress was completed from 2013 to 2014.Water salinity levels at 1.7 ds/m,4 ds/m,6 ds/m and 8 ds/m were used in the experiments.Two water deficit levels were reported,60%and 80%of the irrigation quota,which were considered moderate and mild deficit levels,respectively.All treatments were applied in planting the oil sunflower in critical growing periods,namely,floral initiation,anthesis and maturity.Linear,Cobb-Douglas,quadratic and transcendental function models were used to simulate the relative yield,evapotranspiration(ET)and electrical conductivity(EC).The predictive ability and sensitivity of each model were then evaluated.Compared with salt stress,water stress exerted a more significant effect on the oil sunflower yield;the water parameters(a1 and a3)were most sensitive in the water-salt-crop function model.Oil sunflower was most sensitive to water and salt stress during anthesis.The transcendental function generally showed a relatively high sensitivity coefficient and a relatively small statistical error.Therefore,the transcendental function is the most appropriate model for simulating and predicting the yield of oil sunflower irrigated with saline water.Applying the water-salt-crop function model in planting of oil sunflower can help in the development and utilization of saline water in the Hetao district.
基金funded by Abdulaziz City for Science and Technology,Saudi Arabia(Grant Research No.1-17-04-001-0021).
文摘Water insufficiency is the hampering feature of crop sustainability,especially in arid and semi-arid regions.So,the effectual usage of all water resources especially underground brackish water represents the core priority in Saudi Arabia.The present study aimed to recognize the influence of different types of water irrigation(tap water as a control,salinized well water,and magnetized salinized well water)with or without soil amendments(soil without any amendment as a control,peat-moss,ferrous sulfate,and peat-moss plus ferrous sulfate)on petunia plant growth and flowering as well as ion content.Irrigating Petunia plants with saline well water adversely affected growth and flowering as compared to tap water and magnetized saline well water.Additionally,plants irrigated with magnetized water showed a significant enhancement in all the studied vegetative and flowering growth parameters as compared to those irrigated with salinized well water.Furthermore,mineral contents and survival of Petunia plants irrigated with magnetized well water were higher than those irrigated with tap water.Irrigation with magnetized well water significantly reduced levels of Na+and Cl−ions in leaves of Petunia plants indicating the role of magnetization in alleviating harmful effects of salinity.In conclusion,we recommend the utilization of magnetized saline well water for irrigating Petunia plants either alone or in combination with soil amendments(peat moss plus ferrous sulfate).
基金supported by the National High-Technology R&D Program of China (2013 BAC02B02 and 2013BAC02B01)the National Science Foundation for Young Scientists of China (51409126)+1 种基金the Priority Academic Program Development of Jiangsu Higher Education Institutions, China (1033000001)the Action Plan for Development of Western China of Chinese Academy of Sciences (KZCX 2-XB3-16)
文摘Laboratory and field experiments were conducted to investigate the effects of water application intensity(WAI) on soil salinity management and the growth of Festuca arundinacea(festuca) under three stages of water and salt management strategies using microsprinkler irrigation in Hebei Province, North China. The soil water content(è) and salinity of homogeneous coastal saline soils were evaluated under different water application intensities in the laboratory experiment. The results indicated that the WAI of microsprinkler irrigation influenced the è, electrical conductivity(ECe) and p H of saline soils. As the WAI increased, the average values of è and ECe in the 0–40 cm profile also increased, while their average values in the 40–60 cm profile decreased. The p H value also slightly decreased as depth increased, but no significant differences were observed between the different treatments. The time periods of the water redistribution treatments had no obvious effects. Based on the results for è, ECe and p H, a smaller WAI was more desirable. The field experiment was conducted after being considered the results of the technical parameter experiment and evaporation, wind and leaching duration. The field experiment included three stages of water and salt regulation, based on three soil matric potentials(SMP), in which the SMP at a 20-cm depth below the surface was used to trigger irrigation. The results showed that the microsprinkler irrigation created an appropriate environment for festuca growth through the three stages of water and salt regulation. The low-salinity conditions that occurred at 0–10 cm depth during the first stage(-5 k Pa) continued to expand through the next two stages. The average p H value was less than 8.5. The tiller number of festuca increased as SMP decreased from the first stage to the third stage. After the three stages of water and salt regulation, the highly saline soil gradually changed to a low-saline soil. Overall, based on the salt desalinization, the microsprinkler irrigation and three stages of water and salt regulation could be successfully used to cultivate plants for the reclamation of coastal saline land in North China.
文摘Combining low salinity water (LSW) with surfactants has an enormous potential for enhancing oil recovery processes. However, there is no consensus about the mechanisms involved, in addition to the fact that several studies have been conducted in model systems, while experiments with rocks and reservoir fluids are scarce. This study presents a core-flooding experiment of LSW injection, with and without surfactant, using the core and heavy oil samples obtained from a sandstone reservoir in southeastern Mexico. The effluents and the crude oil obtained at each stage were analyzed. The study was complemented by tomographic analysis. The results revealed that LSW injection and hybrid process with surfactants obtained an increase of 11.4 percentage points in recovery factor. Various phenomena were caused by LSW flooding, such as changes in wettability and pH, ion exchange, mineral dissolution, detachment of fines and modification of the hydrocarbon profile. In the surfactant flooding, the reduction of interfacial tension and alteration of wettability were the main mechanisms involved. The findings of this work also showed that the conditions believed to be necessary for enhanced oil recovery with LSW, such as the presence of kaolinite or high acid number oil, are not relevant.
基金funded by the National Scientific and Technological Supporting Scheme,China (2013BAD05B02 )the Demonstration Plan of Modern Agriculture of Chinese Academy of Sciences (CXJQ120108-2)the support by the Sino-German Center for Research Promotion,Germany (GZ 1149)
文摘In the dominant winter wheat (WW)-summer maize (SM) double cropping system in the low plain located in the North China, limited access to fresh water, especially during dry season, constitutes a major obstacle to realize high crop productivity. Using the vast water resources of the saline upper aquifer for irrigation during WW jointing stage, may help to bridge the peak of dry season and relieve the tight water situation in the region. A field experiment was conducted during 2009-2012 to investigate the effects of saline irrigation during WW jointing stage on soil salt accumulation and productivity of WW and SM. The experiment treatments comprised no irrigation (T1), fresh water irrigation (T2), slightly saline water irrigation (T3:2.8 dS m-l), and strongly saline water irrigation (T4:8.2 dS m-1) at WW jointing stage. With regard to WW yields and aggregated annual WW-SM yields, clear benefits of saline water irrigation (T3 & T4) compared to no irrigation (T1), as well as insignificant yield losses compared to fresh water irrigation (T2) occurred in all three experiment years. However, the increased soil salinity in eady SM season in consequence of saline irrigation exerted a negative effect on SM photosynthesis and final yield in two of three experiment years. To avoid the negative aftereffects of saline irrigation, sufficient fresh water irrigation during SM sowing phase (i.e., increase from 60 to 90 mm) is recommended to guarantee good growth conditions during the sensitive early growing period of SM. The risk of long-term accumulation of salts as a result of saline irrigation during the peak of dry season is considered low, due to deep leaching of salts during regularly occurring wet years, as demonstrated in the 2012 experiment year. Thus, applying saline water irrigation at jointing stage of WW and fresh water at sowing of SM is most promising to realize high yield and fresh irrigation water saving.
基金funded by the National Basic Research Program of China (2009CB825101)the National Natural Science Foundation of China (30960210)
文摘In arid and semi-arid regions, freshwater scarcity and high water salinity are serious and chronic problems for crop production and sustainable agriculture development. We conducted a field experiment to evaluate the effect of irrigation water salinity and nitrogen(N) application rate on soil salinity and cotton yield under drip irrigation during the 2011 and 2012 growing seasons. The experimental design was a 3×4 factorial with three irrigation water salinity levels(0.35, 4.61 and 8.04 dS/m) and four N application rates(0, 240, 360 and 480 kg N/hm2). Results showed that soil water content increased as the salinity of the irrigation water increased, but decreased as the N application rate increased. Soil salinity increased as the salinity of the irrigation water increased. Specifically, soil salinity measured in 1:5 soil:water extracts was 218% higher in the 4.61 dS/m treatment and 347% higher in the 8.04 dS/m treatment than in the 0.35 dS/m treatment. Nitrogen fertilizer application had relatively little effect on soil salinity, increasing salinity by only 3%–9% compared with the unfertilized treatment. Cotton biomass, cotton yield and evapotranspiration(ET) decreased significantly in both years as the salinity of irrigation water increased, and increased as the N application rate increased regardless of irrigation water salinity; however, the positive effects of N application were reduced when the salinity of the irrigation water was 8.04 dS/m. Water use efficiency(WUE) was significantly higher by 11% in the 0.35 dS/m treatment than in the 8.04 dS/m treatment. There was no significant difference in WUE between the 0.35 dS/m treatment and the 4.61 dS/m treatment. The WUE was also significantly affected by the N application rate. The WUE was highest in the 480 kg N/hm2 treatment, being 31% higher than that in the 0 kg N/hm2 treatment and 12% higher than that in the 240 kg N/hm2 treatment. There was no significant difference between the 360 and 480 kg N/hm2 treatments. The N use efficiency(NUE) was significantly lower in the 8.04 dS/m treatment than in either the 4.61 dS/m or the 0.35 dS/m treatment. There was no significant difference in NUE between the latter two treatments. These results suggest that irrigation water with salinity 〈4.61 dS/m does not have an obvious negative effect on cotton production, WUE or NUE under the experimental conditions. Application of N fertilizer(0–360 kg N/hm2) could alleviate salt damage, promote cotton growth, and increase both cotton yield and water use efficiency.
基金funded by the National Natural Science Foundation of China (31360504)the Innovative Research Foundation for Excellent Young Scientists of Xinjiang Production and Construction Crops, China (2014CD002)
文摘Use of saline water in irrigated agriculture has become an important means for alleviating water scarcity in arid and semi-arid regions. The objective of this field experiment was to evaluate the effects of irrigation water salinity and N fertilization on soil physicochemical and biological properties related to nitrification and denitrification. A 3×2 factorial design was used with three levels of irrigation water salinity(0.35, 4.61 and 8.04 d S m-1) and two N rates(0 and 360 kg N ha^(-1)). The results indicated that irrigation water salinity and N fertilization had significant effects on many soil physicochemical properties including water content, salinity, p H, NH_4-N concentration, and NO_3-N concentration. The abundance(i.e., gene copy number) of ammonia-oxidizing archaea(AOA) was greater than that of ammonia-oxidizing bacteria(AOB) in all treatments. Irrigation water salinity had no significant effect on the abundance of AOA or AOB in unfertilized plots. However, saline irrigation water(i.e., the 4.61 and 8.04 d S m-1 treatments) reduced AOA abundance, AOB abundance and potential nitrification rate in N fertilized plots. Regardless of N application rate, saline irrigation water increased urease activity but reduced the activities of both nitrate reductase and nitrite reductase. Irrigation with saline irrigation water significantly reduced cotton biomass, N uptake and yield. Nitrogen application exacerbated the negative effect of saline water. These results suggest that brackish water and saline water irrigation could significantly reduce both the abundance of ammonia oxidizers and potential nitrification rates. The AOA may play a more important role than AOB in nitrification in desert soil.
文摘Saline groundwater is widely distributed in Heilonggang region. While deep confined water is being mined, saline water has not been used in most part of the region. Extension of saline water irrigation is of significance to resolve water shortage, slow down environmental degradation and support the sustainable development of the local agriculture. Four key points are proposed to be managed by comprehensive measures: (1) adapting salt resistant ability; (2) reducing salt input; (3) decreasing soil surface evaporation and salt accumulation in the root zone, and (4) washing away salt from the root zone. Experiments and farming practices demonstrated that brackish water with TDS (total dissolved solids) of 2-5 g/l can be used for crop irrigation. For example, winter wheat can be sustainably irrigated by brackish water with a water limitation of 120 mm every year. Irrigation in combination with different comprehensive measures can increase the efficiency of saline water irrigation.
基金funded by National Key Basic Research Program of China(2010CB428800),Geological Survey(20023064)(12120113102400)
文摘In order to solve water resources problems in the North China Plain, this paper explored human-nature compound water circulation system from three aspects including urban flood control, surface drainage and saline water in the central and eastern of the North China Plain. Results show that:(1) The technical methods have achieved zero increase in rainwater runoff in urban areas,(2) surface drainage depletion problems can be solved through abandoned water and river water separation method,(3) and technical method through promoting rainwater infiltration would be used to solve problem of saline water in the central and eastern parts. This research provides a new perspective to the ultimate solutions to water resources problems in the North China Plain, and a fresh research direction for the development of hydro-geological science.
基金the National Iranian South Oil Company (NISOC) for generously funding the project
文摘An experimental study was performed to investigate the impact of low salinity water on wettability alteration in carbonate core samples from southern Iranian reservoirs by spontaneous imbibition. In this paper, the effect of temperature, salinity,permeability and connate water were investigated by comparing the produced hydrocarbon curves. Contact angle measurements were taken to confirm the alteration of surface wettability of porous media. Oil recovery was enhanced by increasing the dilution ratio of sea water, and there existed an optimum dilution ratio at which the highest oil recovery was achieved. In addition, temperature had a very significant impact on oil recovery from carbonate rocks. Furthermore, oil recovery from a spontaneous imbibition process was directly proportional to the permeability of the core samples. The presence of connate water saturation inside the porous media facilitated oil production significantly. Also, the oil recovery from porous media was highly dependent on ion repulsion/attraction activity of the rock surface which directly impacts on the wettability conditions. Finally, the highest ion attraction percentage was measured for sodium while there was no significant change in pH for all experiments.
基金financially supported by the National Natural Science Foundation of China(Grant Nos. 41872093, 41502096) Foundation of Qinghai Science & Technology Department (2016-ZJ-715) One-Thousand InnovativeTalent Project of Qinghai Province (Grant to QS Fan)
文摘In this study, nineteen brine samples from the Qarhan Salt Lake(QSL) in western China were collected and analyzed for boron(B) and chlorine(Cl) concentrations, total dissolved solids(TDS), pH values and stable B isotopic compositions. The B concentrations and δ^(11) B values of brines in the QSL range from 51.6 mg/L to138.4 mg/L, and from +9.32& to +13.08&, respectively. By comparison of B concentrations and TDS of brines in QSL with evaporation paths of brackish water, we found that B enrichment of brines primarily results from strong evaporation and concentration of Qarhan lake water. Combining with comparisons of B concentrations, TDS, p H values and δ^(11) B values of brines, previously elemental ratios(K/Cl, Mg/Cl, Ca/Cl, B/Cl) and δ^(11) B values of halite from a sediment core(ISL1 A), we observe good correlations between B concentrations and TDS, TDS and pH values, pH and δ^(11) B values of brines, which demonstrate that higher B concentrations and more positive δ^(11) B values of halite indicate higher salinity of the Qarhan paleolake water as well as drier paleoclimatic conditions. Based on this interpretation of the δ^(11) B values of halite in core ISL1 A, higher salinity of the Qarhan paleolake occurred during two intervals, around 46-34 ka and26-9 ka, which are almost coincident with the upper and lower halite-dominated salt layers in core ISL1 A,drier climate phases documented from the δ^(18) O record of carbonate in core ISL1 A and the paleomoisture record in monsoonal central Asia, and a higher solar insolation at 30°N. These results demonstrate that the δ^(11) B values of halite in the arid Qaidam Basin could be regarded as a new proxy for reconstructing the salinity record of paleolake water as well as paleoclimate conditions.
基金The Science and Technology Development in Tianjin(No.033112211)
文摘Yellow River water transfer for Tianjin is important in solving the water shortage in Tianjin, which facilitate economic development and social progress for many years. Fresh water drawn from Yellow River( i. e., Yin-Huang water) becomes saltier and saltier when being stored in the Bei-Da-Gang reservoir. We qualitatively analyze the water salinization mechanism based on mass transfer theory. The main factors are salinity transfer of saline soil, evaporation concentrating, and the agitation of wind. A simulative experimental pond and an evaporation pond were built beside the Bei-Da-Gang reservoir to quantitatively investigate the water salinization based on water and solute balance in the simulative pond. 80% of increased [Cl^-] is due to the salinity transfer of the saline soil and the other 20% is due to evaporation concentrating, so the former is the most important factor. We found that the salinization of Yin-Huang water can be described with a zero-dimension linear model.
基金supported by the China Foundation for the Author of National Excellent Doctoral Dissertation (201457)the National Natural Science Foundation of China (91125024)
文摘Groundwater-fed lakes are essential for the ecology in arid and semiarid regions.As a typical arid region,the Badain Jaran Desert (BJD) is famous in the world for the presence of a large number of groundwater-fed saline lakes among the mega dunes.Based on the up to date geological surveys and observations,this study analyzed the groundwater contributions in water-salt balances of the lakes in the desert.We found different types of springs,including the sublacustrine springs that indicate an upward flow of groundwater under the lakebed.A simplified water balance model was developed to analyze the seasonal variations of water level in the Sumu Barun Jaran Lake,which revealed an approximately steady groundwater discharge in the lake and explained why the amplitude of seasonal changes in lake level is less than 0.5 m.In addition,a salt balance model was developed to evaluate the salt accumulations in the groundwater-fed lakes.The relative salt accumulation time is 800–7,000 years in typical saline lakes,which were estimated from the concentration of Cl-,indicating a long history evolution for the lakes in the BJD.Further researches are recommended to provide comprehensive investigations on the interactions between the lakes and groundwater in the BJD.