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Quantifying source and dynamics of acidic pollution in a coastal acid sulphate soil area Full text
2013
Phong, N.D. | To Phuc Tuong | Phu, N.D. | Nang, N.D. | Hoanh, Chu Thai
Quantifying source and dynamics of acidic pollution in a coastal acid sulphate soil area Full text
2013
Phong, N.D. | To Phuc Tuong | Phu, N.D. | Nang, N.D. | Hoanh, Chu Thai
The in-depth knowledge on management and reducing annual acidic pollution is important for improving the sustainable livelihood of people living in areas with acid sulphate soils (ASS). This study involved a long-term (2001-2006), large-scale canal water quality monitoring network (87 locations) and a field experiment at nine sites to quantify the dynamic variability of acidic pollution and its source in a coastal area with ASS in the Mekong River Delta of Vietnam. Widespread acidic pollution (pH <5) of surface water occurred at the beginning of the rainy season, while pH of the canal water remained high (7-8) at the end of the rainy season and during the dry season. The study identified canal embankment deposits, made of ASS spoils from canal dredging/excavation, as the main source of acidic pollution in the surrounding canal network. The findings suggested that there was a linkage between the amount of acidic loads into canal networks and the age of the embankment deposits. The most acute pollution (pH ~ 3) occurred in canals with sluggish tidal water flow, at 1-2 years after the deposition of excavated spoils onto the embankments in ASS. The amount of acidic loads transferred to the canal networks could be quantified from environmental parameters, including cumulative rainfall, soil type and age of embankment deposits. The study implied that dredging/excavation of canals in ASS areas must be carried out judiciously as these activities may increase the source of acidic pollution to the surrounding water bodies.
Show more [+] Less [-]Quantifying source and dynamics of acidic pollution in a coastal acid sulphate soil area Full text
2013
Phong, N. D. | Tuong, T. P. | Phu, N. D. | Nang, N. D. | Hoanh, Chu Thai
The in-depth knowledge on management and reducing annual acidic pollution is important for improving the sustainable livelihood of people living in areas with acid sulphate soils (ASS). This study involved a long-term (2001–2006), large-scale canal water quality monitoring network (87 locations) and a field experiment at nine sites to quantify the dynamic variability of acidic pollution and its source in a coastal area with ASS in the Mekong River Delta of Vietnam. Widespread acidic pollution (pH <5) of surface water occurred at the beginning of the rainy season, while pH of the canal water remained high (7–8) at the end of the rainy season and during the dry season. The study identified canal embankment deposits, made of ASS spoils from canal dredging/excavation, as the main source of acidic pollution in the surrounding canal network. The findings suggested that there was a linkage between the amount of acidic loads into canal networks and the age of the embankment deposits. The most acute pollution (pH ~ 3) occurred in canals with sluggish tidal water flow, at 1–2 years after the deposition of excavated spoils onto the embankments in ASS. The amount of acidic loads transferred to the canal networks could be quantified from environmental parameters, including cumulative rainfall, soil type and age of embankment deposits. The study implied that dredging/excavation of canals in ASS areas must be carried out judiciously as these activities may increase the source of acidic pollution to the surrounding water bodies.
Show more [+] Less [-]Surface water quality, public health, and ecological risks in Bangladesh—a systematic review and meta-analysis over the last two decades Full text
2023
Bilal, H. | Li, X. | Iqbal, Muhammad Shahid | Mu, Y. | Tulcan, R. X. S. | Ghufran, M. A.
Surface water quality, public health, and ecological risks in Bangladesh—a systematic review and meta-analysis over the last two decades Full text
2023
Bilal, H. | Li, X. | Iqbal, Muhammad Shahid | Mu, Y. | Tulcan, R. X. S. | Ghufran, M. A.
Water quality has recently emerged as one of the utmost severe ecological problems being faced by the developing countries all over the world, and Bangladesh is no exception. Both surface and groundwater sources contain different contaminants, which lead to numerous deaths due to water-borne diseases, particularly among children. This study presents one of the most comprehensive reviews on the current status of water quality in Bangladesh with a special emphasis on both conventional pollutants and emerging contaminants. Data show that urban rivers in Bangladesh are in a critical condition, especially Korotoa, Teesta, Rupsha, Pashur, and Padma. The Buriganga River and few locations in the Turag, Balu, Sitalakhya, and Karnaphuli rivers have dissolvable oxygen (DO) levels of almost zero. Many waterways contain traces of NO3, NO2, and PO4-3 pollutants. The majority of the rivers in Bangladesh also have Zn, Cu, Fe, Pb, Cd, Ni, Mn, As, and Cr concentrations that exceed the WHO permissible limits for safe drinking water, while their metal concentrations exceed the safety threshold for irrigation. Mercury poses the greatest hazard with 90.91% of the samples falling into the highest risk category. Mercury is followed by zinc 57.53% and copper 29.16% in terms of the dangers they pose to public health and the ecosystem. Results show that a considerable percentage of the population is at risk, being exposed to contaminated water. Despite hundreds of cryptosporidiosis cases reported, fecal contamination, i.e., Cryptosporidium, is totally ignored and need serious considerations to be regularly monitored in source water.
Show more [+] Less [-]Surface water quality, public health, and ecological risks in Bangladesh—a systematic review and meta-analysis over the last two decades Full text
[Protective utilization of water and land in the Bistrica river basin [Montenegro, Yugoslavia]]
1998
Popovic, V. (Institut za zemljiste, Beograd (Yugoslavia)) | Ivanovic, S. | Ivanovic, S. | Petrovic, P.
In this paper, we are consider processing of soils erosion and his way on protection expoitation of water for population water supply, melioration's systems for irrigation and for strew of manger of the Lim river with the tug and suspend bank (Montenegro, Yugoslavia). We are given suggestions for protective utilization of agricultural and forest lands and the possibilities of water exploitation from Bistrica river (Montenegro, Yugoslavia). That is useful for fishing, irrigation, energetic, tourism and water supply. In this paper, you can meet some suggestions about exploitations of minerals and organic fertilizars that are not toxics and they not any influence on pollution of land and water.
Show more [+] Less [-]The monetary facilities payment for ecosystem services as an approach to restore the Degraded Urmia Lake in Iran. Full text
2023
Daneshi, Alireza | Azadi, Hossein | Panahi, Mostafa | Islami, Iman | Vafakhah, Mehdi | Mirzaeipour, Zahra
peer reviewed | This study analyzed the potential use of Payment for Ecosystem Services (PES) as a strategy for improving water supply management. This study focused on the Siminehroud Sub-basin due to its high importance to the Basin of Urmia Lake (UL). Siminehroud is the second provider of water (by volume) to Urmia Lake. To evaluate the technical and economic feasibility of a PES scheme, the current land use map was extracted using satellite imagery. In addition, the two algorithms of Support Vector Machines (SVMs) and Maximum Likelihood (ML) are used for Landsat images classification, rather than analyzing the relationship between land use and ecosystem services. Then, the most relevant ecosystem services provided in the region were evaluated using the Benefit Transfer Method. In the last step, by designing and implementing a survey, on the one hand, the local farmers' Willingness to Accept (WTA) cash payments for reducing the area they cultivate, and on the other hand, the farmers' Willingness to Pay (WTP) for managing the water consumption were determined. The results illustrated that the WTA program is more acceptable among the beneficiaries. It is also notable that this program needs very high governmental funding. Furthermore, the results of the program indicate that the land area out of the cultivation cycle will gradually increase while the price of agricultural water will also increase.
Show more [+] Less [-]Expert systems in water quality management
1999
Djordjevic, B. (Univerzitet u Beogradu, Beograd (Yugoslavia). Gradjevinski fakultet)
Expert system (ES) is a software which unites mathematical models, empirical knowledge, expert evaluation, engineering intuition, heuristic rules and necessary informations which through the inference engine gives useful advise to the decision maker, to reach a correct and timely decision. The objectives of ES cover a wide range of tasks of protection of waters, out of which the following seem to be the most important: diagnostics, monitoring, estimation, interpretation, planning and design of systems, maintenance, trouble shooting, education, management.
Show more [+] Less [-]Phosphorus internal loading and sediment diagenesis in a large eutrophic lake (Lake Chaohu, China) Full text
2022
Yang, Chunhui | Li, Jiying | Yin, Hongbin
Sediment phosphorus (P) release and retention are important in controlling whole-system P dynamics and budget in eutrophic lakes. Here we combine short- (seasonal) and long-term (years to decades) studies to quantify the internal P loading and P release potential in the sediments of Lake Chaohu and explore their controlling mechanisms. In the west region of the lake, short-term P diffusive fluxes ranged from 0.2 mg/m²·d⁻¹ to 6.69 mg/m²·d⁻¹ (averaged 2.76 mg/m²·d⁻¹) and long-term net P release ranged from 2.25 mg/m²·d⁻¹ to 8.94 mg/m²·d⁻¹ (averaged 5.34 mg/m²·d⁻¹); in the east region, short-term P diffusive fluxes varied from 0.73 mg/m²·d⁻¹ to 1.76 mg/m²·d⁻¹ (averaged 1.05 mg/m²·d⁻¹) and long-term P release ranged from 0.13 mg/m²·d⁻¹ to 4.15 mg/m²·d⁻¹ (averaged 1.3 mg/m²·d⁻¹). Both short- and long-term P releases were in the same order of magnitudes as the external P inputs (3.56 mg/m²·d⁻¹). Comparison of the long-term and short-term sediment P release indicates that while the high summer P release in the east might only represent a snapshot value, the sediments in the west contribute to large P release for years or even decades, impeding water quality recovery under lake management. Mobilization of surface sediment legacy P accounted for 81% of short-term P release. The long-term release was dominated by remobilization of iron bond P (BD-P) (average 52.1%) at all sites, while Aluminium-bound P (NaOH-rP) exhibited partly reactive and potentially mobile, releasing P to the water column in most sites in the west. Our study demonstrates the importance of sediments as P sources in lake Chaohu. The combination of short- and long-term P release studies can help understand the roles of sediments in regulating the water quality and eutrophication.
Show more [+] Less [-]Polystyrene nanoplastic contamination mixed with polycyclic aromatic hydrocarbons: Alleviation on gas exchange, water management, chlorophyll fluorescence and antioxidant capacity in wheat Full text
2022
Arikan, Busra | Ozfidan-Konakci, Ceyda | Yildiztugay, Evren | Turan, Metin | Cavusoglu, Halit
Polycyclic aromatic hydrocarbons (PAHs) constitute a significant environmental pollution group that reaches toxic levels with anthropogenic activities. The adverse effects of nanoplastics accumulating in ecosystems with the degradation of plastic wastes are also a growing concern. Previous studies have generally focused on the impact of single PAH or plastic fragments exposure on plants. However, it is well recognized that these contaminants co-exist at varying rates in agricultural soil and water resources. Therefore, it is critical to elucidate the phytotoxicity and interaction mechanisms of mixed pollutants. The current study was designed to comparatively investigate the single and combined effects of anthracene (ANT, 100 mg L⁻¹), fluorene (FLU, 100 mg L⁻¹) and polystyrene nanoplastics (PS, 100 mg L⁻¹) contaminations in wheat. Plants exposed to single ANT, FLU and PS treatments demonstrated decline in growth, water content, high stomatal limitations and oxidative damage. The effect of ANT + FLU on these parameters was more detrimental. In addition, ANT and/or FLU treatments significantly suppressed photosynthetic capacity as determined by carbon assimilation rate (A) and chlorophyll a fluorescence transient. The antioxidant system was not fully activated (decreased superoxide dismutase, peroxidase and glutathione reductase) under ANT + FLU, then hydrogen peroxide (H₂O₂) content (by 2.7-fold) and thiobarbituric acid reactive substances (TBARS) (by 2.8-fold) increased. Interestingly, ANT + PS and FLU + PS improved the growth, water relations and gas exchange parameters. The presence of nanoplastics recovered the adverse effects of ANT and FLU on growth by protecting the photosynthetic photochemistry and reducing oxidative stress. PAH plus PS reduced the ANT and FLU accumulation in wheat leaves. In parallel, the increased antioxidant system, regeneration of ascorbate, glutathione and glutathione redox status observed under ANT + PS and FLU + PS. These findings will provide an information about the phytotoxicity mechanisms of mixed pollutants in the environment.
Show more [+] Less [-]Effect of applying calcium peroxide on the accumulation of arsenic in rice plants grown in arsenic-elevated paddy soils Full text
2020
Syu, Chien-Hui | Yu, Chih-Han | Lee, Dar-Yuan
Water management such as drainage for creating aerobic conditions is considered to be an adequate method for reducing the accumulation of arsenic (As) in rice grains; however, it is difficult to conduct drainage operations in some areas that experience a lengthy rainy season as well as in soils with poor drainage. In this regard, application of oxygen-releasing compounds (ORCs) may be an alternative method for maintaining aerobic conditions even under flooding in paddy soils. Therefore, a pot experiment was conducted to investigate the effects of application of an ORC, calcium peroxide (CaO₂), on the growth and accumulation of As in rice plants grown in As-contaminated paddy soils. The rice plants were grown in two soils with different characteristics and As levels, and all of the tested soils were treated with 0, 5, 10, and 20 g CaO₂ kg⁻¹. Results revealed that the concentration of As and the distribution of arsenite in the pore water of all tested soils was reduced by CaO₂ application. In addition, the grain yields increased and the concentration of inorganic As in brown rice decreased by 25–45% upon CaO₂ treatment of low-As-level soils (<16 mg kg⁻¹). However, the effect of CaO₂ application on the accumulation of inorganic As in brown rice in As-enriched soils (>78 mg kg⁻¹) could not found in this study, due to the rice plant suffered from serious As phytotoxicity. It suggests that CaO₂ amendment may be suitable for reducing the As concentration of rice grains grown in low-As-level paddy soils, but for As-enriched soils, the proposed CaO₂ application method is not feasible.
Show more [+] Less [-]Global scanning of selective serotonin reuptake inhibitors: occurrence, wastewater treatment and hazards in aquatic systems Full text
2019
Mole, Rachel A. | Brooks, Bryan W.
As the global population becomes more concentrated in urban areas, resource consumption, including access to pharmaceuticals, is increasing and chemical use is also increasingly concentrated. Unfortunately, implementation of waste management systems and wastewater treatment infrastructure is not yet meeting these global megatrends. Herein, pharmaceuticals are indicators of an urbanizing water cycle; antidepressants are among the most commonly studied classes of these contaminants of emerging concern. In the present study, we performed a unique global hazard assessment of selective serotonin reuptake inhibitors (SSRIs) in water matrices across geographic regions and for common wastewater treatment technologies. SSRIs in the environment have primarily been reported from Europe (50%) followed by North America (38%) and Asia-Pacific (10%). Minimal to no monitoring data exists for many developing regions of the world, including Africa and South America. From probabilistic environmental exposure distributions, 5th and 95th percentiles for all SSRIs across all geographic regions were 2.31 and 3022.1 ng/L for influent, 5.3 and 841.6 ng/L for effluent, 0.8 and 127.7 ng/L for freshwater, and 0.5 and 22.3 ng/L for coastal and marine systems, respectively. To estimate the potential hazards of SSRIs in the aquatic environment, percent exceedances of therapeutic hazard values of specific SSRIs, without recommended safety factors, were identified within and among geographic regions. For influent sewage and wastewater effluents, sertraline exceedances were observed 49% and 29% of the time, respectively, demonstrating the need to better understand emerging water quality hazards of SSRIs in urban freshwater and coastal ecosystems. This unique global review and analysis identified regions where more monitoring is necessary, and compounds requiring toxicological attention, particularly with increasing aquatic reports of behavioral perturbations elicited by SSRIs.
Show more [+] Less [-]Water management impacts the soil microbial communities and total arsenic and methylated arsenicals in rice grains Full text
2019
The bioavailability of the metalloid arsenic (As) in paddy soil is controlled by microbial cycling of As and other elements such as iron (Fe) and sulfur (S), which are strongly influenced by water management in paddy fields. In this study, we evaluated how water management affects As bioavailability by growing rice plants in a geogenic As-contaminated soil. We determined As speciation in soil porewater and the diversity of the associated microbial community. Continuous flooding enhanced the release of Fe and As and increased arsenite (As(III)) and methylated As species concentrations in the rice grain compared with aerobic treatment. Total inorganic and organic As in the grain was 84% and 81% lower, respectively, in the aerobic treatment compared with the continuous flooding treatment. The amounts of Fe(III)-reducing bacteria (FeRB) increased in the flooded rhizosphere soil. The abundance of FeRB in the soil correlated with the dissolution of Fe and As. Among the As-transformation genes quantified, the aioA gene for As(III) oxidation and arsM gene for As(III) methylation were most abundant. The arsM copy number correlated positively with the levels of dsrB (dissimilatory (bi) sulfite reductase β-subunit), suggesting that dissimilatory sulfate-reducing bacteria (SRB) may play an important role in dimethylarsenate (DMAs(V)) production in soil. Our results show that decreased populations of rhizosphere FeRB and SRB contributed to a lower bioavailability of As, and decreased production of methylated arsenicals under oxic conditions.
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