Artykuły w czasopismach na temat „Nutrient pollution of water”
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1
Zhao, Haiping, Qingxue Li i Jianhua Tao. "Spatio-temporal patterns and source identification of surface water pollution in Bohai Bay, China from 1995 to 2005". World Journal of Engineering 11, nr 6 (1.12.2014): 605–12. http://dx.doi.org/10.1260/1708-5284.11.6.605.
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Several multivariate statistical methods were comprehensively used to interpret the temporal, spatial patterns and source identification of surface water pollution in Bohai Bay with the large and complex data. Twelve variables water quality indices were surveyed at 12 sites three times a year (May, August, and October) from 1995 to 2005. Cluster analysis (CA) grouped the eleven years into two clusters, Cluster A (1995 to 2001 except 1998) and cluster B (2002 to 2005 and 1998), and spatial CA divided the entire area into three groups. The results of discriminant analysis showed that the temporal CA and spatial CA were effective with 90% and 83.3% correct assignments, respectively. In cluster A, the pollution sources mainly were nutrient factor from non-point source and Hg pollution, oil and organic pollutions were relatively light. In Cluster B, the organic pollution became the mainly pollution source, and the nutrient pollution was still serious problem. In the results of spatial analysis, the group 1 was mainly affected by anthropogenic pollution, the group 3 was seriously affected by oil spill pollution and nutrients pollution, and the group 2 reflected relatively strong water self-purification ability.
2
Mladenović-Ranisavljević, Ivana, Milovan Vuković, Violeta Stefanović i Ljiljana Takić. "Multicriteria Decision Analysis of Sites with Increased Nutrient Contents in Water". Water 14, nr 23 (23.11.2022): 3810. http://dx.doi.org/10.3390/w14233810.
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Nutrient pollution represents an ongoing problem and a great challenge to water resources management around the world. Therefore, the aim of this paper is to contribute to the efforts of the water resources management in considering a problem of the nutrient pollution of water from a multicriteria decision-making point of view. The combined PROMETHEE and GAIA analysis in this paper included indicators of nutrients in the water (total nitrogen, nitrite, nitrate, ammonium ion, total phosphorus, and orthophosphates) to rank and evaluate significant sites along the Danube River flow through Serbia. Furthermore, the ecological quality status of the water was determined which places the Danube River into the category of “good” to “moderate” water quality. The results represent a detailed evaluation of the sites with increased nutrient content, associated with the most dominant parameters of nutrient indicators affecting water pollution at each site. The main sources of nonpoint pollution are of anthropogenic origin reflected in agricultural applications of pesticides and fertilizers, together with natural contamination of ground and water sources, while pollution from point sources arises from industrial waste waters as well as from domestic activities. Minimizing the application of fertilizers and pesticides is a way to control pollution from agricultural activities while, at the same time, a proper wastewater treatment is needed to reduce point sources, although financial aspects and lack of funds are limiting factors of this control in Serbia. Therefore, the findings in this paper could serve environmental scientists and water resources managers as a starting point in identifying key sources of nutrient pollution in water, as well as industry experts and national authorities in expanding strategies and taking long-term measures to reduce the input of nutrients into the valuable Danube River.
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Beasley, E. L., M. A. Hiller i R. B. Biggs. "Susceptibility of U.S. Estuaries to Pollution". Water Science and Technology 20, nr 6-7 (1.06.1988): 211–19. http://dx.doi.org/10.2166/wst.1988.0205.
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Utilizing data primarily from the U.S. Department of Commerce, both estuaries and watersheds for 78 U.S. systems are analyzed. Watersheds are classified according to total population and discrete subpopulations. The Vollenweider approach, which compares hydraulic loading to nutrient loading of lakes, is adapted to estuaries. By considering total population as a surrogate of point source nutrients, agricultural workers as a surrogate of non-point source toxics and nutrients and chemical + metal workers as a surrogate of point source toxics, we can estimate potential anthropogenic impacts on watersheds. When these surrogates are plotted against hydraulic loading, managers have a tool to identify estuaries most likely to be under greatest anthropogenic presaure. The estuaries with highest susceptibility from total population, as well as the estuaries with the the highest susceptibility to toxic stress, are identified. On a Vollenweider diagram, the phosphorous loadings of freshwater bodies are plotted as a function of hydraulic loading. The permissible-excessive phosphorous loadings have been both theoretically and empirically determined. We have replotted the freshwater data and added 33 U.S. estuary P loadings that were previously unavailable. Estuaries plot on the Vollenweider diagram as a continuum of fresh waterbodies, both in terms of hydraulic loading and phosphorus loading. Most estuaries appear to have permissible P loadings. Analysis of nutrient loading (normalized to hydraulic loading) versus water quality parameters like chlorophyll a indicates that estuaries are more efficient users of nutrients than are freshwater bodies, and that they reach a “nutrient saturation point”. Perhaps this is due to grazing or turbidity. It appears that, in general, the OECD eutrophication modeling approach is applicable to estuarine systems as well as lakes and impoundments.
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Kronvang, Brian, Frank Wendland, Karel Kovar i Dico Fraters. "Land Use and Water Quality". Water 12, nr 9 (28.08.2020): 2412. http://dx.doi.org/10.3390/w12092412.
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The interaction between land use and water quality is of great importance worldwide as agriculture has been proven to exert a huge pressure on the quality of groundwater and surface waters due to excess losses of nutrients (nitrogen and phosphorous) through leaching and erosion processes. These losses result in, inter alia, high nitrate concentrations in groundwater and eutrophication of rivers, lakes and coastal waters. Combatting especially non-point losses of nutrients has been a hot topic for river basin managers worldwide, and new important mitigation measures to reduce the input of nutrients into groundwater and surface waters at the pollution source have been developed and implemented in many countries. This Special Issue of the Land use and Water Quality conference series (LuWQ) includes a total of 11 papers covering topics such as: (i) nitrogen surplus; (ii) protection of groundwater from pollution; (iii) nutrient sources of pollution and dynamics in catchments and (iv) new technologies for monitoring, mapping and analysing water quality.
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Yan, Jing, Nathaniel A. Bogie i Teamrat A. Ghezzehei. "Root uptake under mismatched distributions of water and nutrients in the root zone". Biogeosciences 17, nr 24 (17.12.2020): 6377–92. http://dx.doi.org/10.5194/bg-17-6377-2020.
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Abstract. Most plants derive their water and nutrient needs from soils where the resources are often scarce, patchy, and ephemeral. It is not uncommon for plant roots to encounter mismatched patches of water-rich and nutrient-rich regions in natural environments. Such an uneven distribution of resources necessitates plant reliance on strategies for exploring and acquiring nutrients from relatively dry patches. We conducted a laboratory study that elucidates the biophysical mechanisms that enable this adaptation. The roots of tomato (Solanum lycopersicum) seedlings were laterally split and grown in two adjacent, hydraulically disconnected pots, which permitted precise control of water and nutrient applications to each compartment. We observed that the physical separation of water-rich and nutrient-rich compartments (one received 90 % water and 0 % nutrients and the other received 10 % water and 100 % nutrients) does not significantly stunt plant growth and productivity compared to two control treatments (control 1: 90 % water and 100 % nutrients versus 10 % water and 0 % nutrients; control 2: 50 % water and 50 % nutrients in each compartment). Specifically, we showed that soil dryness does not reduce nutrient uptake, vegetative growth, flowering, and fruiting compared to control treatments. We identified localized root proliferation in nutrient-rich dry soil patches as a critical strategy that enabled nutrient capture. We observed nocturnal rewetting of the nutrient-rich but dry soil zone (10 % water and 100 % nutrients) but not in the nutrient-free and dry zone of the control experiment (90 % water and 100 % nutrients). We interpreted the rewetting as the transfer of water from the wet to dry zones through roots, a process commonly known as hydraulic redistribution (HR). The occurrence of HR likely prevents the nutrient-rich soil from drying due to permanent wilting and the subsequent decline of root functions. Sustaining rhizosphere wetness is also likely to increase nutrient mobility and uptake. Lack of HR in the absence of nutrients suggests that HR is not entirely a passive, water-potential-gradient driven flow. The density and size of root hairs appeared to be higher (qualitative observation) in the nutrient-rich and dry compartments than in the nutrient-free and dry compartments. We also observed organic coating on sand grains in the rhizosphere of the nutrient-rich and dry compartments. The observations are consistent with prior observations that root hairs and rhizodeposition aid rhizosphere wetting. These findings were synthesized in a conceptual model that explains how plants of dry regions may be adapted to mismatched resources. This study also suggests that separating the bulk of applied nutrients from the frequently irrigated soil region can increase nutrient use efficiency and curtail water pollution from intensive agricultural systems.
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PUCKETT, LARRY J. "Identifying the Major Sources of Nutrient Water Pollution". Environmental Science & Technology 29, nr 9 (wrzesień 1995): 408A—414A. http://dx.doi.org/10.1021/es00009a743.
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Randall, C. W. "The environmental, economic and societal consequences of inadequate nitrogen pollution controls". Water Science and Technology 49, nr 5-6 (1.03.2004): 23–33. http://dx.doi.org/10.2166/wst.2004.0733.
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Because adequate nutrient controls were not established in the USA and other countries when there were past opportunities to do so, nutrient pollution of estuaries and coastal waters has resulted in the impairment of ecosystems and major reductions or collapse of fisheries at numerous sites around the world, resulting in major economic and societal impacts. The root problem is that political policies and processes have permitted municipalities, developers, industries and farmers to expand and operate without paying the full cost of their activities. Their expanded activities have occurred at the expense and displacement of those who rely on the productivity and recreational value of our estuarine and coastal waters. Some governments have developed remedial nutrient control programs, but most of them have been poorly conceived, under funded and inadequately enforced, resulting in small increments of progress that tend to be lost because of inadequate land use and immigration controls. It is proposed that establishment of comprehensive nutrient controls is needed throughout the world to preserve and protect estuarine and coastal waters, and to protect or re-establish fisheries, for both economic and societal stability. Nitrogen is the key nutrient for the establishment of control strategies. It is recommended that nutrient recovery from wastewaters and controlled reuse of both water and nutrients be widely implemented as a part of nutrient control strategies.
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Moss, Brian. "Water pollution by agriculture". Philosophical Transactions of the Royal Society B: Biological Sciences 363, nr 1491 (30.07.2007): 659–66. http://dx.doi.org/10.1098/rstb.2007.2176.
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Agriculture disrupts all freshwater systems hugely from their pristine states. The former reductionist concept of pollution was of examining individual effects of particular substances on individual taxa or sub-communities in freshwater systems, an essentially ecotoxicological concept. It is now less useful than a more holistic approach that treats the impacts on the system as a whole and includes physical impacts such as drainage and physical modification of river channels and modification of the catchment as well as nutrient, particulate and biocide pollution. The European Water Framework Directive implicitly recognizes this in requiring restoration of water bodies to ‘good ecological quality’, which is defined as only slightly different from pristine state. The implications for the management of agriculture are far more profound than is currently widely realized.
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de Lima Barros, Alessandra Maciel, Maria do Carmo Sobral i Günter Gunkel. "Modelling of point and diffuse pollution: application of the Moneris model in the Ipojuca river basin, Pernambuco State, Brazil". Water Science and Technology 68, nr 2 (1.07.2013): 357–65. http://dx.doi.org/10.2166/wst.2013.086.
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Emissions of pollutants and nutrients are causing several problems in aquatic ecosystems, and in general an excess of nutrients, specifically nitrogen and phosphorus, is responsible for the eutrophication process in water bodies. In most developed countries, more attention is given to diffuse pollution because problems with point pollution have already been solved. In many non-developed countries basic data for point and diffuse pollution are not available. The focus of the presented studies is to quantify nutrient emissions from point and diffuse sources in the Ipojuca river basin, Pernambuco State, Brazil, using the Moneris model (Modelling Nutrient Emissions in River Systems). This model has been developed in Germany and has already been implemented in more than 600 river basins. The model is mainly based on river flow, water quality and geographical information system data. According to the Moneris model results, untreated domestic sewage is the major source of nutrients in the Ipojuca river basin. The Moneris model has shown itself to be a useful tool that allows the identification and quantification of point and diffuse nutrient sources, thus enabling the adoption of measures to reduce them. The Moneris model, conducted for the first time in a tropical river basin with intermittent flow, can be used as a reference for implementation in other watersheds.
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Zeng, Chun Fen, La Chun Wang, Wen Yu Huang i Wei Wang. "Research on Influencing Factors of Water Environment in the Typical Western of Taihu Lake Based on the Principal Component Analysis - A Case Study of Tianmuhu Lake and Gehu Lake in Jiangsu Province". Advanced Materials Research 356-360 (październik 2011): 924–28. http://dx.doi.org/10.4028/www.scientific.net/amr.356-360.924.
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Taihu Lake basin is a typical water shortage area for water quality problem in China. Studying the influencing water environment factors in this area provides a scientific basis to propose effective pollution water control. This article selects lakes in the western basin as the study area which has the largest contribution to the pollution in Taihu Lake. Influencing factors of water pollution of Tianmuhu Lake and Gehu Lake have been analyzed based on principal component analysis of SPSS, to study the major influencing factors of water environment. The results show that the major influencing factors of water environment in Taihu Lake is dissolved oxygen, water turbidity, and water N, P and other nutrient elements, and the water environment nutrients is much influenced by the N element. While the major influencing factors of water environment in Gehu Lake is P nutrition elements, physical and chemical factors and nutrients such as N and P element, and P elements are seriously polluted. Thus, the corresponding countermeasures should be forward according to different water characteristics during the process of water Pollution Control at the basin.
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Hastings, Florencia, Mario Pérez-Bidegain, Rafael Navas i Angela Gorgoglione. "Impacts of irrigation development on water quality in the San Salvador watershed (Part 2): Implementation of scenarios in SWAT". Agrociencia Uruguay 27, NE1 (6.02.2024): e1199. http://dx.doi.org/10.31285/agro.27.1199.
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Intensive agricultural activities pose a significant threat to water quality as critical non-point sources of pollution. Effective mitigation strategies demand understanding the causes and processes of water pollution. This study aimed to quantify the impacts of irrigation development on water quality and assess best management practices for sustainable agriculture intensification. Employing the calibrated SWAT model for the San Salvador watershed (baseline scenario), two scenarios were implemented and evaluated: the first one depicted irrigation development from a future reservoir, and the second integrated riparian buffer zones to minimize nutrient and sediment losses. Notably the baseline scenario did not achieve nutrient water quality objectives. Results revealed that irrigation development increases nutrient yields, driving the future reservoir toward eutrophication. Implementing riparian buffer zones reduced nutrient loss, but additional measures are necessary for sustainable environmental goals at the basin scale. This research contributes with valuable insights for formulating effective management strategies to minimize nutrient pollution in water and safeguard water quality and biodiversity in the basin.
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Costa Jr., Ozeas S. "Anthropogenic nutrient pollution of coral reefs in Southern Bahia, Brazil". Brazilian Journal of Oceanography 55, nr 4 (grudzień 2007): 265–79. http://dx.doi.org/10.1590/s1679-87592007000400004.
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Spatial, temporal and anthropogenic controls on nutrient distribution were evaluated for nearshore and offshore reefs at Porto Seguro Bay, Southern Bahia. Water samples were analysed for total oxidised nitrogen (TON), soluble reactive phosphorus (SRP), reactive silica (DSi), and chlorophyll a (Chl). The results indicate that rainfall promotes a significant (F=19.873, p<0.001) increase in the load of nutrients to nearshore (average 12% increase) and offshore reefs (average 31% increase). Nutrient concentrations at the urbanized reef (TON=1.93-3.21µM; SRP=0.57-0.89µM; DSi=8.48-11.15µM) are on average 25% higher than at non-urban reefs and over 200% higher than the offshore reef. The urbanized reef also presented the highest rates of increase in nutrient input between dry and rainy seasons (TON=+0.36µM; SRP=+0.08µM; DSi=+0.70µM). Differences in nutrient concentration between nearshore and offshore reefs are more pronounced during dry season, when the bulk of land-based nutrient contribution is confined to the nearshore reefs. SRP values in the study area ranked among the highest in the world for coral reef areas and phytoplankton growth appears to be nitrogen-limited.
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Tank, Jennifer, i Alexander Reisinger. "Nutrient Limitation and Uptake Rates in Streams and Rivers of the Greater Yellowstone Ecosystem". UW National Parks Service Research Station Annual Reports 36 (1.01.2013): 153–59. http://dx.doi.org/10.13001/uwnpsrc.2013.4011.
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Nutrient pollution of aquatic ecosystems is a growing concern as the influence of human activities continues to increase on the landscape. Headwater streams have long been shown to process nutrients via the biofilm community growing on the bottom of streams. The growth and activity of these biofilms is often limited by the availability of nitrogen (N), phosphorus (P), or co-limited by both N and P. Although small stream nutrient dynamics are relatively well understood, comparatively little is known about larger, non-wadeable rivers. Biofilms on the river bottom are likely still nutrient limited, but there becomes an increased potential for light limitation as rivers increase in depth. In addition to biofilms on the bottom of rivers, free-living microbial communities suspended in the water column also occur in rivers and process nutrients - a component of nutrient processing largely ignored in streams. In summer 2013 we worked in streams and rivers of the Greater Yellowstone Area (GYA) to establish the nutrient limitation status of minimally-impacted rivers, as well as the role of the water column in processing nutrients as streams increase in size. For both the nutrient limitation and water column uptake studies, we are using the GYA sites in addition to systems from other regions of the US to establish what controls the various aspects of nutrient dynamics in rivers. Our results from the GYA, in addition to Midwest and Southwest US rivers, will provide water quality managers with new strategies for improving water quality downstream, and clarify mechanisms controlling nutrient retention in rivers.
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Giang, P. H., H. Harada, S. Fujii, N. P. H. Lien, H. T. Hai, P. N. Anh i S. Tanaka. "Transition of fertilizer application and agricultural pollution loads: a case study in the Nhue-Day River basin". Water Science and Technology 72, nr 7 (16.06.2015): 1072–81. http://dx.doi.org/10.2166/wst.2015.312.
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Rapid socio-economic development in suburban areas of developing countries has induced changes in agricultural waste and nutrient management, resulting in water pollution. The study aimed at estimating agricultural nutrient cycles and their contribution to the water environment. A material flow model of nitrogen (N) and phosphorus (P) was developed focusing on agricultural activities from 1980 to 2010 in Trai hamlet, an agricultural watershed in Nhue-Day River basin, Vietnam. The model focused on the change in household management of human excreta and livestock excreta, and chemical fertilizer consumption. The results showed that the proportion of nutrients from compost/manure applied to paddy fields decreased from 85 to 41% for both N and P between 1980 and 2010. The nutrient inputs derived from chemical fertilizer decreased 6% between 1980 and 2000 for both N and P. Then, these nutrients increased 1.4 times for N and 1.2 times for P from 2000 to 2010. As of 2010, the total inputs to paddy fields have amounted to 435 kg-N/ha/year and 90 kg-P/ha/year. Of these nutrient inputs, 40% of N and 65% of P were derived from chemical fertilizer. Thirty per cent (30%) of total N input was discharged to the water bodies through agricultural runoff and 47% of total P input accumulated in soil.
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Hong, Jiarui, Jing Zhang, Yongyu Song i Xin Cao. "Spatial and Temporal Distribution Characteristics of Nutrient Elements and Heavy Metals in Surface Water of Tibet, China and Their Pollution Assessment". Water 14, nr 22 (14.11.2022): 3664. http://dx.doi.org/10.3390/w14223664.
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In the context of global climate change, the ecological environment of Tibet has been gaining attention given its unique geographical and fragile nature. In this study, to understand the pollution status of the surface water of Tibet, China, we collected monthly data of 12 indicators from 41 cross-sectional monitoring sites in 2021 and analyzed the spatial and temporal variations of nutrients and heavy metal elements, water quality conditions, and pollutant sources in surface water. All 12 polluting elements, except lead (Pb), had significant seasonal variations, but the magnitude of the differences was very small. Spatially, nutrient elements were relatively concentrated in the agricultural and pastoral development areas in central and northern Tibet. In general, the water quality in most parts of Tibet was found to be good, and the water quality of 41 monitoring sections belonged to Class I water standard as per the entropy method–fuzzy evaluation method. The study used a multivariate statistical method to analyze the sources of pollution factors. The principal component analysis method identified four principal components. The results of this study can provide a scientific basis for pollution prevention and control in the Tibet Autonomous Region, and contribute to further research on water ecology.
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Relf, P. Diane, i David McKissack. "CONSUMER NUTRIENT MANAGEMENT CALENDAR". HortScience 25, nr 9 (wrzesień 1990): 1114b—1114. http://dx.doi.org/10.21273/hortsci.25.9.1114b.
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The Virginia Gardener Nutrient Management Education Program addressed non-point, urban-runoff pollution of Virginia's streams, estuaries, and groundwater, and included a calendar aimed at alerting the garden consumer to the connection between overfertilization and water pollution. Over 15,000 calendars were requested.A survey of calendar recipients was conducted. 1500 persons were chosen at random, a subsequent address check confirmed adequate distribution among the regions of the state. The response rate was 28%. Responses indicated that 91.3% of those surveyed had changed their garden practices in some way because of the calendar. 90% of the respondents indicated that the calendar had shown them a connection between proper gardening techniques and water quality, with 82.2% indicating the calendar had been moderately to greatly successful in showing them this connection.The 1989 Virginia Gardener Calendar was an effective method of educating garden consumers about the connection between water quality and nutrient runoff, and cultural practices which lessen the need for fertilizer in the home garden.
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Loboda, N. S., i A. M. Kuza. "Environmental risks assessment of the Kogylnyk River nutrient pollution based on probit functions". Ukrainian hydrometeorological journal, nr 32 (27.12.2023): 34–49. http://dx.doi.org/10.31481/uhmj.32.2023.03.
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The relevance of the study is associated with the need to determine the risks of high and catastrophic levels of water pollution of the Kogylnyk River. The water quality of this river affects the environmental condition of the northern part of Sasyk lake and reservoir. This artificial reservoir that was created as part of the estuary used to be one of components of the Danube-Dniester irrigation system in the past and can be used for irrigation in the post-war period in the future. As the North-Western Black Sea region is an agricultural region of Ukraine, the article focuses on the pollution of the river by specific nutrients (ammonium, nitrite, nitrate, phosphate). The subject of the study covers the environmental risks assessment of the Kogylnyk River present-day pollution. Hydrochemical observations of the State Water Resources Agency of Ukraine were used as input materials of the research. Such observations were carried out across the upper (below the border with the Republic of Moldova) and lower sections of the river. The number of samples taken in the upper section was 80, and 56 – in the lower section. Water quality was assessed using a modified water pollution index (WPI). The risks of nutrient pollution were evaluated based on a statistical approach using a probit function. It was found that the water quality in the upper section is worse than the one in the lower section. The research indicated a close correspondence between water quality indicators and environmental risk values. In the upper section, the risks of catastrophic pollution have a probability of their occurrence that is equal to 46.1%, and the risks of high pollution – 41.1%, with 87.2% constituting a total percentage. In the lower section, the probability of a high level pollution risk is equal to 33.3%, with no critical risk identified during the observation period. The trophic status of the water body along the river length varies from hypertrophic and polytrophic on the upper course to eutrophic and mesotrophic on the lower course. The decrease in pollution levels in the river's lower section is due to the processes of biological, physical and chemical self-purification of the aquatic ecosystem. Since nutrients have a predominantly anthropogenic origin, the water quality improvement of the Kogylnyk River across the territory of Ukraine is associated with the reduced flow of municipal and agricultural wastewater entering the river. Nutrient pollution requires implementation of additional measures such as improving the culture of farming taking place in the catchment area (for example, during conservation of fertilizers and their application).
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Voogt, W. "THE DEVELOPMENT OF CLOSED GROWING SYSTEMS IN THE NETHERLANDS AS A MEANS TO REDUCE ENVIRONMENTAL POLLUTION". HortScience 29, nr 4 (kwiecień 1994): 255a—255. http://dx.doi.org/10.21273/hortsci.29.4.255a.
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In the Netherlands, many crops in protected cultivation changed from soil to soilless culture in recent years. The reasons for this development were problems with soil sterilization and better growth control with soilless culture, which led to considerable yield increases. However, the growing systems used, with free leachate drainage, contribute highly to pollution of the ground and surface water with minerals (N and P). To reduce this emission, closed growing systems were developed, i.e., systems with recirculating nutrient solutions. Inherent to these systems, however, were problems such as the rapid spread of pathogens in the root environment. Methods were developed for disinfestation of the nutrient solution. Salt accumulation was also a concern, the concentrations of ions in the water used for closed systems must be lower than the uptake capacity of the plants. To avoid depletion and accumulation of certain nutrients. the addition of nutrients should be adapted to the demand during the cropping period. For this purpose, nutrient solutions and guidelines for adjustments during the cropping period were developed for several crops.
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Lawniczak-Malińska, Agnieszka, Bogumił Nowak i Kamil Pajewski. "Agricultural Pressures on the Quality of Ground and Surface Waters in Catchments of Artificial Reservoirs". Water 15, nr 4 (8.02.2023): 661. http://dx.doi.org/10.3390/w15040661.
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Changes in nutrient concentrations in groundwater were investigated to determine the impact of agriculture on water quality in artificial lakes. The study covered three reservoirs in an agricultural area of Wielkopolska (central-western part of Poland). Assessing the agricultural impact required a network of piezometers around the reservoirs, used to determine the degree of groundwater pollution from nutrients supplied to the reservoirs. Moreover, the analysis covered the quality of water in streams flowing into the reservoirs, and in the reservoirs themselves. Field research was conducted every month of the growing season from March to November. The analysis covered land inclination, ground permeability, and soil type. Detailed objectives included: (1) assessment of the agricultural impact on the chemical parameters of ground and surface water quality, and (2) evaluation of the impact of different sources of agricultural pollution on water quality in artificial reservoirs in regards to their management. This study revealed high dynamics of nutrient concentrations, particularly for nitrates and phosphates, in groundwater and surface water. A significant effect of maize cultivation on an increase in nitrate concentrations in the groundwater of the catchment of the Przebędowo Reservoir was evidenced, as well as a substantial effect of the functioning of an animal farm on the quality of groundwaters in the catchment of the Lachotka Reservoir. The nutrient load of agricultural origin in the catchment of the Miedzichowo Reservoir was relatively low. Our study revealed elevated amounts of nutrients such as nitrogen and phosphorus, detected more frequently in groundwater than in running waters, which confirms our hypothesis of the importance of groundwater analysis in detecting the source of pollution of the studied lakes. High nutrient concentrations recorded in groundwater leached from arable fields were also observed in the summer period, failing to confirm the hypothesis that the greatest effect of factors would be related to the spring effect of arable fields on water quality (lack of compact vegetation cover, high water level, etc.). Our study also indicated a greater importance of the type of land use than lithology or permeability of deposits.
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Mosheim, Roberto, i Robin C. Sickles. "Spatial effects of nutrient pollution on drinking water production". Empirical Economics 60, nr 6 (10.03.2021): 2741–64. http://dx.doi.org/10.1007/s00181-021-02019-1.
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Angalika, Misigo W. S., Seiji Suzuki, Truc-Ly Le-Huynh, Tomoaki Itayama i Wataru Tanaka. "Assessing nutrient budget of ungauged catchment using intermittent water quality markers". Maejo International Journal of Energy and Environmental Communication 4, nr 3 (28.09.2022): 1–10. http://dx.doi.org/10.54279/mijeec.v4i3.247534.
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This study is a preliminary spatial-temporal assessment method of the ungauged catchment to determine the variation in water quality (WQ) and the land use influence on river basins’ health. The intermittent WQ data, the principal component analysis, and the redundancy analysis were used to evaluate the (dis)similarity among the 10 ungauged streams and their significance in the entire catchment. These revealed some similarities/differences in nutrient pollution and latent land-use influence on the streams’ health. There were similarities between R6-R7, R9-R10, among R1 to R4 basins, while R5 and R8 had distinct variances in their WQ dynamics. The intensive vegetable and rice production in R5, R7, R8, R9, and R10 basins were the major sources of high nutrient concentrations. The unique variations, especially in R5 and R8 basins could be attributed to other different pollution sources. Hence, it’s of great significance to carry out comprehensive research in the above 5 river basins. That is the efficiency of management practices, identification of pollution sources, and the extent to which the elevated nutrients in the streams interact with biota within the river regime. This research offers a method to evaluate WQ dynamics in relation to human interferences in river basins of a catchment with limited data under similar climatic conditions.
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Zheng, Yuexin, Qianyang Wang, Xuan Zhang, Jingshan Yu, Chong Li, Liwen Chen i Yuan Liu. "Nitrogen and Phosphorus Retention Risk Assessment in a Drinking Water Source Area under Anthropogenic Activities". Remote Sensing 14, nr 9 (26.04.2022): 2070. http://dx.doi.org/10.3390/rs14092070.
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Excessive nitrogen (N) and phosphorus (P) input resulting from anthropogenic activities seriously threatens the supply security of drinking water sources. Assessing nutrient input and export as well as retention risks is critical to ensuring the quality and safety of drinking water sources. Conventional balance methods for nutrient estimation rely on statistical data and a huge number of estimation coefficients, which introduces uncertainty into the model results. This study aimed to propose a convenient, reliable, and accurate nutrient prediction model to evaluate the potential nutrient retention risks of drinking water sources and reduce the uncertainty inherent in the traditional balance model. The spatial distribution of pollutants was characterized using time-series satellite images. By embedding human activity indicators, machine learning models, such as Random Forest (RF), Support Vector Machine (SVM), and Multiple Linear Regression (MLR), were constructed to estimate the input and export of nutrients. We demonstrated the proposed model’s potential using a case study in the Yanghe Reservoir Basin in the North China Plain. The results indicate that the area information concerning pollution source types was effectively established based on a multi-temporal fusion method and the RF classification algorithm, and the overall classification low-end accuracy was 92%. The SVM model was found to be the best in terms of predicting nutrient input and export. The determination coefficient (R2) and Root Mean Square Error (RMSE) of N input, P input, N export, and P export were 0.95, 0.94, 0.91, and 0.93, respectively, and 32.75, 5.18, 1.45, and 0.18, respectively. The low export ratios (2.8–3.0% and 1.1–2.2%) of N and P, the ratio of export to input, further confirmed that more than 97% and 98% of N and P, respectively, were retained in the watershed, which poses a pollution risk to the soil and the quality of drinking water sources. This nutrient prediction model is able to improve the accuracy of non-point source pollution risk assessment and provide useful information for water environment management in drinking water source regions.
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Li, H. E., J. H. W. Lee, A. Koenig i A. W. Jayawardena. "Nutrient load estimation in nonpoint source pollution of Hong Kong region". Water Science and Technology 51, nr 3-4 (1.02.2005): 209–16. http://dx.doi.org/10.2166/wst.2005.0593.
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Red tides and eutrophication have been frequently observed over the past two decades in coastal waters around Hong Kong, which are caused by many factors and one of them is the nutrient from nonpoint source pollution (NSP). This paper concentrates on the nutrients carried by river flow from watersheds. Since there are no systematical data sets of nonpoint source pollution in Hong Kong, monthly river water quality measurements, rainfall and river flow data, land uses, and other related information are used to analyze the characteristics of NSP and estimate the nutrient loads for Hong Kong region. Main achievements are as follows: firstly, besides mean concentration for single land use, the concept of integrated mean concentration for mixed land uses was proposed and applied. Secondly, mean concentrations were carried out for different land uses (agriculture, town, grassland, shrubland and woodland), each Water Control Zone, and Hong Kong region. Thirdly, the annual nutrient loads were estimated, for the first time in this paper, with various methods for the whole area of Hong Kong, and about 8,000 tons of TN and 1,500 tons TP are transported into coastal waters from Hong Kong's land in 1998.
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Zhao, Zhonghe, Gaohuan Liu, Qingsheng Liu, Chong Huang i He Li. "Studies on the Spatiotemporal Variability of River Water Quality and Its Relationships with Soil and Precipitation: A Case Study of the Mun River Basin in Thailand". International Journal of Environmental Research and Public Health 15, nr 11 (5.11.2018): 2466. http://dx.doi.org/10.3390/ijerph15112466.
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Human activities can affect soil nutrients, thereby influencing river water quality. The spatial pattern of precipitation also impacts distributions of water quality. In this paper, we employed a method that combines point survey, soil, and water quality data to analyze the spatial relationships between precipitation, soil nutrient and water quality in the basin on the basis of field surveys and laboratory analysis. The ordinary kriging method was applied to interpolate the precipitation and soil data, and the spatial pattern was analyzed. The water samples on the main stream and soil samples in the field were collected during both the dry and rainy seasons to analyze the water quality and soil nutrients. The results indicate: (1) The water quality in the dry season is better than that in the rainy season, the water quality in the upper reaches is better than that in the lower reaches, and agricultural activity is the direct source of water pollution. (2) The precipitation in the rainy and dry seasons is differente and the dilution effect of precipitation on pollutant concentrations and transport of water flow affect the spatial distribution of water quality. (3) There is a significant difference in the spatial pattern of soil nutrients between the dry and rainy seasons, and the soil nutrient content and the surface runoff directly affect the water quality. Soil nutrients are affected by human activities, and they potentially act as nonpoint source (NPS) pollution in this river basin. To improve the water quality, suitable agriculture measures need to be implemented.
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Pandey, Shuchita, Rahul Soni i Poornima Devi. "Phycoremediation - A Clean Technology for Water Pollution Abatement". International Journal of Research and Review 10, nr 11 (28.11.2023): 490–503. http://dx.doi.org/10.52403/ijrr.20231157.
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Phycoremediation has been utilised to remediate wastewater and successfully lower nutrient levels. There isn’t many research, though, on how well phycoremediation works to lower nitrogen levels in eutrophic lakes. This review concentrates on the process and variables involved in using algae. Before considering the possibility of algal-based approaches in remediating lake eutrophication, to remove nutrients and contaminants from wastewater. Algal biofilm, algal grass scrubbers, high-rate algal ponds (HRAP), and immobilised algae are methods used in phycoremediation of wastewater. A wastewater treatment method based on microalgae lowers BOD, prevents coli forms, eliminates pollutants and nutrients, and removes heavy metals. The sixth sustainable development target of the UNDP cannot be attained without phytoremediation. Microalgae can effectively treat wastewater at a very low cost, and the biomass they produce can be used to produce biofuels. The cost-effective growing of microalgae and contaminants with wastewater can be replaced by the successful coupling of microalgae with wastewater, which can also scale up production of high-value products. This review mainly focused on the potential of algae and their specific mechanisms involved in wastewater treatment and energy recovery systems leading to important industrial precursors. The review is highly beneficial for scientists, wastewater treatment plant operators, freshwater managers, and industrial communities to support the sustainable development of natural resources. Keywords: Algae, Biodegradation, Pollutant removal, Phycoremediation, Wastewater treatment.
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Yang, Xiaoqing, Mingkai Leng, Xuguang Ge, Xiaodong Wu, Haoran Liu, Guiying Lin, Zhi Huang i Yuhan Chen. "Characterization and Risk Assessment of Nutrient and Heavy Metal Pollution in Surface Sediments of Representative Lakes in Yangxin County, China". Sustainability 16, nr 6 (7.03.2024): 2252. http://dx.doi.org/10.3390/su16062252.
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Increased urbanization and industrialization globally have led to the widespread pollution of water bodies (e.g., lakes) by heavy metals (HMs) and nutrients. These pollutants accumulate in water and surface sediments, posing risks to both aquatic organisms and human health. In November 2022, surface sediment samples from three lakes—Lianhua Lake, Mati Lake, and North Lake—were collected to assess nutrient (nitrogen and phosphorous) and HM content. Total N (TN), total P (TP), and HM concentrations were analyzed. The pollution status was evaluated using comprehensive pollution index (FF) methods and the potential ecological risk index (RI) (Eri). The results were as follows: (1) Variations in nutrient and HM contents were observed among the three lakes. Lianhua Lake exhibited the highest average TN content (1600 mg/kg), while North Lake had the highest average TP content (2230 mg/kg). The average concentrations of Cd, Hg, and As in the surface sediment surpassed the soil background values of Hubei Province, reaching 1.41, 2.74, and 1.76 times the background values, respectively. Notably, Hg exceeded the standard in Lianhua Lake by 3.39 times, followed by North Lake (2.52 times) and Mati Lake (2.24 times). (2) The FF and potential Eri revealed that the average RI values for Mati Lake, North Lake, and Lianhua Lake were 106.88, 126.63, and 162.18, respectively. These indices categorized the ecological risk levels as moderate, while nutrient salts in the surface water reached a severe pollution level. (3) Correlation and PCA indicated that Cu, Pb, Cd, and Ni were linked to mineral smelting, aquaculture feed, and agricultural fertilizers. Hg and nutrient salts originated from atmospheric deposition of surrounding domestic waste water and traffic exhaust gases. Agricultural activities seemed to contribute to As concentration in the lakes, while Cr has its main origin in the weathering of the rock matrix.
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Greenhalgh, Suzie, i Paul Faeth. "A Potential Integrated Water Quality Strategy for the Mississippi River Basin and the Gulf of Mexico". Scientific World JOURNAL 1 (2001): 976–83. http://dx.doi.org/10.1100/tsw.2001.354.
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Nutrient pollution, now the leading cause of water quality impairment in the U.S., has had significant impact on the nation’s waterways. Excessive nutrient pollution has been linked to habitat loss, fish kills, blooms of toxic algae, and hypoxia (oxygen-depleted water). The hypoxic “dead zone” in the Gulf of Mexico is one of the most striking illustrations of what can happen when too many nutrients from inland watersheds reach coastal areas. Despite programs to improve municipal wastewater treatment facilities, more stringent industrial wastewater requirements, and agricultural programs designed to reduce sediment loads in waterways, water quality and nutrient pollution continues to be a problem, and in many cases has worsened. We undertook a policy analysis to assess how the agricultural community could better reduce its contribution to the dead zone and also to evaluate the synergistic impacts of these policies on other environmental concerns such as climate change. Using a sectorial model of U.S. agriculture, we compared policies including untargeted conservation subsidies, nutrient trading, Conservation Reserve Program extension, agricultural sales of carbon and greenhouse gas credits, and fertilizer reduction. This economic and environmental analysis is watershed-based, primarily focusing on nitrogen in the Mississippi River basin, which allowed us to assess the distribution of nitrogen reduction in streams, environmental co-benefits, and impact on agricultural cash flows within the Mississippi River basin from various options. The model incorporates a number of environmental factors, making it possible to get a more a complete picture of the costs and co-benefits of nutrient reduction. These elements also help to identify the policy options that minimize the costs to farmers and maximize benefits to society.
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Wang, Huan, Qi Li i Jun Xu. "Climate Warming Does Not Override Eutrophication, but Facilitates Nutrient Release from Sediment and Motivates Eutrophic Process". Microorganisms 11, nr 4 (31.03.2023): 910. http://dx.doi.org/10.3390/microorganisms11040910.
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The climate is changing. The average temperature in Wuhan, China, is forecast to increase by at least 4.5 °C over the next century. Shallow lakes are important components of the biosphere, but they are sensitive to climate change and nutrient pollution. We hypothesized that nutrient concentration is the key determinant of nutrient fluxes at the water-sediment interface, and that increased temperature increases nutrient movement to the water column because warming stimulates shifts in microbial composition and function. Here, twenty-four mesocosms, mimicking shallow lake ecosystems, were used to study the effects of warming by 4.5 °C above ambient temperature at two levels of nutrients relevant to current degrees of lake eutrophication levels. This study lasted for 7 months (April–October) under conditions of near-natural light. Intact sediments from two different trophic lakes (hypertrophic and mesotrophic) were used, separately. Environmental factors and bacterial community compositions of overlying water and sediment were measured at monthly intervals (including nutrient fluxes, chlorophyll a [chl a], water conductivity, pH, sediment characteristics, and sediment-water et al.). In low nutrient treatment, warming significantly increased chl a in the overlying waters and bottom water conductivity, it also drives a shift in microbial functional composition towards more conducive sediment carbon and nitrogen emissions. In addition, summer warming significantly accelerates the release of inorganic nutrients from the sediment, to which microorganisms make an important contribution. In high nutrient treatment, by contrast, the chl a was significantly decreased by warming, and the nutrient fluxes of sediment were significantly enhanced, warming had considerably smaller effects on benthic nutrient fluxes. Our results suggest that the process of eutrophication could be significantly accelerated in current projections of global warming, especially in shallow unstratified clear-water lakes dominated by macrophytes.
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Niu, Lixia, Pieter van Gelder, Xiangxin Luo, Huayang Cai, Tao Zhang i Qingshu Yang. "Implications of Nutrient Enrichment and Related Environmental Impacts in the Pearl River Estuary, China: Characterizing the Seasonal Influence of Riverine Input". Water 12, nr 11 (19.11.2020): 3245. http://dx.doi.org/10.3390/w12113245.
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The Pearl River estuary is an ecologically dynamic region located in southern China that experiences strong gradients in its biogeochemical properties. This study examined the seasonality of nutrient dynamics, identified related environmental responses, and evaluated how river discharge regulated nutrient sink and source. The field investigation showed significant differences of dissolved nutrients with seasons and three zones of the estuary regarding the estuarine characteristics. Spatially, nutrients exhibited a clear decreasing trend along the salinity gradient; temporally, their levels were obviously higher in summer than other seasons. The aquatic environment was overall eutrophic, as a result of increased fluxes of nitrogen and silicate. This estuary was thus highly sensitive to nutrient enrichment and related pollution of eutrophication. River discharge, oceanic current, and atmospheric deposition distinctly influenced the nutrient status. These factors accordingly may influence phytoplankton that are of importance in coastal ecosystems. Phytoplankton (in terms of chlorophyll) was potentially phosphate limited, which then more frequently resulted in nutrient pollution and blooms. Additionally, the nutrient sources were implied according to the cause–effect chains between nutrients, hydrology, and chlorophyll, identified by the PCA-generated quantification. Nitrogen was constrained by marine-riverine waters and their mutual increase-decline trend, and a new source was supplemented along the transport from river to sea, while a different source of terrestrial emission from coastal cities contributed to phosphate greatly.
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Xaxiri, Eirini, Evangelos Darivakis, Ioannis Karavidas, Georgia Ntatsi i Dimitrios Savvas. "Comparing the Nutritional Needs of Two Solanaceae and One Cucurbitaceae Species Grown Hydroponically under the Same Cropping Conditions". Plants 12, nr 20 (22.10.2023): 3642. http://dx.doi.org/10.3390/plants12203642.
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Switching over to closed-loop soilless culture systems, thus preventing pollution of water resources by nitrates and saving water and fertilizers, requires accurate estimations of the mean nutrient-to-water uptake ratios. To contribute to this objective, three fruit vegetable species (tomato, eggplant, cucumber) were grown hydroponically in a floating system under identical cropping conditions to quantify species differences in nutrient uptake. The composition of the nutrient solution used to feed the crops was identical for all species. The total water consumption and the concentrations of most nutrients (K, Ca, Mg, N, P, Fe, Mn, Zn, Cu, B) in the nutrient solution and the plant tissues were measured at crop establishment and at two different crop developmental stages. The obtained data were used to determine the uptake concentrations (UCs) using two mass balance models, one based on nutrient removal from the nutrient solution and a second based on nutrient recovery in the plant tissues. The experiment was conducted in the spring–summer season. The results revealed that the nutrient uptake concentrations were substantially different between species for all nutrients except for N, while there were also significant interactions between the two methods used for their estimation of some nutrients. Thus, the UCs of N, P, Ca, and some micronutrients were significantly higher when its estimation was based on the removal of nutrients from the nutrient solution compared to recovery from plant tissues, presumably because with the first method, losses due to denitrification or precipitation could not be separated from those of plant uptake. The comparison of the three greenhouse vegetables revealed a similar UC for nitrogen, while cucumber generally showed significantly lower UCs for P and for the micronutrients Fe, Zn, and Cu at both cropping stages compared to the two Solanaceae species. The obtained results can be used to precisely adjust the nutrient supply in closed-loop soilless cultivations to the plant uptake thus avoiding both depletion and accumulation of nutrients in the root environment.
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Bae, M. S., i S. R. Ha. "Nonlinear regression approach to evaluate nutrient delivery coefficient". Water Science and Technology 53, nr 2 (1.01.2006): 271–79. http://dx.doi.org/10.2166/wst.2006.061.
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Implementation of the Korean Total Maximum Daily Load Act calls for new tools to quantify nutrient losses from diffuse sources at a river basin district scale. In this study, it was elucidated that the nonlinear regression model (NRM) reduces the uncertainty of the boundary conditions of the water quality model. The NRM was proposed to analyse the delivery coefficients of surface waters and retention coefficients of pollutants. Delivery coefficient of pollution load was considered as a function of two variables: the watershed form ratio, Sf, which is a measurable geomorphologic variable and the retention coefficient, ϕ, which is an empirical constant representing the basin-wide retarding capacity of pollutant wash-off. This model was applied on the Geum River, one of the major basins in South Korea. The QUAL2E was used to simulate stream water quality using NRM. In this paper, we elucidate the possibility to use a nonlinear regression model for delivery and retention of nutrients in a drainage basin characterized as both data-rich and data-poor, and the magnitude of the nutrient loads and sources has been uncertain for a long time. Keywords Delivery coefficient; diffuse pollution; pollution load runoff; retention coefficient
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Frei, Rebecca J., Gabriella M. Lawson, Adam J. Norris, Gabriel Cano, Maria Camila Vargas, Elizabeth Kujanpää, Austin Hopkins i in. "Limited progress in nutrient pollution in the U.S. caused by spatially persistent nutrient sources". PLOS ONE 16, nr 11 (29.11.2021): e0258952. http://dx.doi.org/10.1371/journal.pone.0258952.
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Human agriculture, wastewater, and use of fossil fuels have saturated ecosystems with nitrogen and phosphorus, threatening biodiversity and human water security at a global scale. Despite efforts to reduce nutrient pollution, carbon and nutrient concentrations have increased or remained high in many regions. Here, we applied a new ecohydrological framework to ~12,000 water samples collected by the U.S. Environmental Protection Agency from streams and lakes across the contiguous U.S. to identify spatial and temporal patterns in nutrient concentrations and leverage (an indicator of flux). For the contiguous U.S. and within ecoregions, we quantified trends for sites sampled repeatedly from 2000 to 2019, the persistence of spatial patterns over that period, and the patch size of nutrient sources and sinks. While we observed various temporal trends across ecoregions, the spatial patterns of nutrient and carbon concentrations in streams were persistent across and within ecoregions, potentially because of historical nutrient legacies, consistent nutrient sources, and inherent differences in nutrient removal capacity for various ecosystems. Watersheds showed strong critical source area dynamics in that 2–8% of the land area accounted for 75% of the estimated flux. Variability in nutrient contribution was greatest in catchments smaller than 250 km2 for most parameters. An ensemble of four machine learning models confirmed previously observed relationships between nutrient concentrations and a combination of land use and land cover, demonstrating how human activity and inherent nutrient removal capacity interactively determine nutrient balance. These findings suggest that targeted nutrient interventions in a small portion of the landscape could substantially improve water quality at continental scales. We recommend a dual approach of first prioritizing the reduction of nutrient inputs in catchments that exert disproportionate influence on downstream water chemistry, and second, enhancing nutrient removal capacity by restoring hydrological connectivity both laterally and vertically in stream networks.
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Qi, Yiting, Xin Cao, Ruisi Cao, Mingjie Cao, Ailan Yan, Erpeng Li i Dong Xu. "Research on the Analysis of and Countermeasures for the Eutrophication of Water Bodies: Waihu Reservoir as a Case Study". Processes 12, nr 4 (15.04.2024): 796. http://dx.doi.org/10.3390/pr12040796.
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Water quality deterioration and eutrophication have become a global concern, while reservoir pollution caused by multiple factors has led to frequent algal blooms, posing a serious threat to rural drinking water security and urban water supply. The purpose of this paper is to analyze the current water quality of Waihu Reservoir and use the single index method, the weighted comprehensive scoring method, and the nutrient level index method (TLI) to evaluate eutrophication. On this basis, the pollution sources of the reservoir are comprehensively analyzed and discussed, and effective control strategies are proposed. The evaluation results indicate that the reservoir is of moderate eutrophication type. Therefore, reducing the input of nutrients such as nitrogen and phosphorus in water is the main goal of alleviating exogenous pollution. The combination of engineering intervention and ecological restoration strategies to remove nutrients from the aquatic environment is an effective strategy to manage endogenous pollution. From the point of view of the source of pollution, this study provides an in-depth analysis of exogenous and endogenous pollution, respectively, and the proposed treatment is instructive for the control and routine management of eutrophication in the Waihu Reservoir, as well as for the management of similar problems in different reservoirs.
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Liao, Ren Kuan, Pei Ling Yang, Shu Mei Ren, Hang Yi, Bo Zhou i Zhu Zhou. "Effects of Typical Chemical Agents on Prevention of Non-Point-Source (NPS) Pollution in a Sloping Orchard". Advanced Materials Research 550-553 (lipiec 2012): 1168–72. http://dx.doi.org/10.4028/www.scientific.net/amr.550-553.1168.
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In this paper, two typical chemical agents SAP and PAM were selected to reduce NPS pollution. Soil water content, nutrient transport and soil erosion have been researched. The results showed that the water deep percolation was reduced and the moisture of root zone increased by 3.6%-12.69% after chemical agents application; PAM can immobile soil grains, and significantly reduce soil erosion on sloping land by 25.5%-53.4%. The synergies of PAM and SAP can significantly influence transport of nutrients in the soil vertical profile, moreover, the content of nutrient was enriched in root zone that the content of Nitrate-N increased 14.7% and Ammonium-N increased 9.8%. It can been found that CL2 (SAP150 kg/k㎡+PAM4.5 kg/k㎡) treatment is superior to CL1 (SAP150 kg/k㎡+PAM2.25 kg/k㎡) in soil moisture conservation and reducing NPS pollution in two slopes orchards.
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Meals, Donald W. "Watershed-scale response to agricultural diffuse pollution control programs in Vermont, USA". Water Science and Technology 33, nr 4-5 (1.02.1996): 197–204. http://dx.doi.org/10.2166/wst.1996.0505.
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From 1979 to 1990, the LaPlatte River Watershed and the St. Albans Bay Watershed Rural Clean Water Program projects in Vermont (USA) sought to reduce sediment, nutrient, and bacteria loads to parts of Lake Champlain impaired by eutrophication. Best Management Practices (BMPs) to control diffuse sources of pollution from dairy agriculture were widely implemented through a voluntary program of technical assistance and cost-sharing by agencies of the U.S. Department of Agriculture. Intensive water quality monitoring was undertaken to document water quality changes resulting from the land treatment programs, including studies of BMP effectiveness and long-term watershed-scale trend monitoring. Some BMPs significantly reduced edge-of-field pollutant delivery to surface waters. Phosphorus export from corn fields was up to 1500% higher where manure was winter spread and up to 15% of the phosphorus applied in winter-spread manure was lost in runoff. A vegetated filter strip retained more than 90% of sediment and nutrients in milking center waste and functioned effectively year-round. Watershed-level response, however, was not simply the sum of edge-of-field changes. Sediment concentration and export decreased in both project areas, but anticipated decreases in nutrient concentrations and loads did not occur. The most significant water quality trends observed were 50–75% reductions in indicator bacteria counts in all study watersheds. Factors contributing to the lack of general response in nutrient levels, recommendations for future agricultural pollution control projects, and implications for planning of diffuse source pollution control programs are discussed.
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Savvas, Dimitrios, Evangelos Giannothanasis, Theodora Ntanasi, Ioannis Karavidas i Georgia Ntatsi. "State of the Art and New Technologies to Recycle the Fertigation Effluents in Closed Soilless Cropping Systems Aiming to Maximise Water and Nutrient Use Efficiency in Greenhouse Crops". Agronomy 14, nr 1 (26.12.2023): 61. http://dx.doi.org/10.3390/agronomy14010061.
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Inappropriate fertilisation results in the pollution of groundwater with nitrates and phosphates, eutrophication in surface water, emission of greenhouse gasses, and unwanted N deposition in natural environments, thereby harming the whole ecosystem. In greenhouses, the cultivation in closed-loop soilless culture systems (CLSs) allows for the collection and recycling of the drainage solution, thus minimising contamination of water resources by nutrient emissions originating from the fertigation effluents. Recycling of the DS represents an ecologically sound technology as it can reduce water consumption by 20–35% and fertiliser use by 40–50% in greenhouse crops, while minimising or even eliminating losses of nutrients, thereby preventing environmental pollution by NO3− and P. The nutrient supply in CLSs is largely based on the anticipated ratio between the mass of a nutrient absorbed by the crop and the volume of water, expressed as mmol L−1, commonly referenced to as “uptake concentration” (UC). However, although the UCs exhibit stability over time under optimal climatic conditions, some deviations at different locations and different cropping stages can occur, leading to the accumulation or depletion of nutrients in the root zone. Although these may be small in the short term, they can reach harmful levels when summed up over longer periods, resulting in serious nutrient imbalances and crop damage. To prevent large nutrient imbalances in the root zone, the composition of the supplied nutrient solution must be frequently readjusted, taking into consideration the current nutrient status in the root zone of the crop. The standard practice to estimate the current nutrient status in the root zone is to regularly collect samples of drainage solution and determine the nutrient concentrations through chemical analyses. However, as results from a chemical laboratory are available several days after sample selection, there is currently intensive research activity aiming to develop ion-selective electrodes (ISEs) for online measurement of the DS composition in real-time. Furthermore, innovative decision support systems (DSSs) fed with the analytical results transmitted either offline or online can substantially contribute to timely and appropriate readjustments of the nutrient supply using as feedback information the current nutrient status in the root zone. The purpose of the present paper is to review the currently applied technologies for nutrient and water recycling in CLSs, as well as the new trends based on ISEs and novel DSSs. Furthermore, a specialised DSS named NUTRISENSE, which can contribute to more efficient management of nutrient supply and salt accumulation in closed-loop soilless cultivations, is presented.
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Muhammetoğlu, A., H. Muhammetoğlu i S. Soyupak. "Evaluation of efficiencies of diffuse allochthonous and autochthonous nutrient input control in restoration of a highly eutrophic lake". Water Science and Technology 45, nr 9 (1.05.2002): 195–203. http://dx.doi.org/10.2166/wst.2002.0238.
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Mogan Lake is an important recreational area for Metropolitan Ankara-Turkey. It is a shallow eutrophic lake with a dense growth of macrophytes. The main contributors of nutrients and other pollutants to the lake are the creeks carrying the runoff water from the watershed and upland farming land, in addition to the domestic and industrial wastewater discharges from a nearby town and industries. Hydrodynamic and water quality modeling techniques were used to determine the optimum management schemes for the lake restoration and diffuse pollution control. Management scenarios were devised and tested to control allochthonous and autochthonous nutrient inputs to the lake. Phosphorus and nitrogen load reductions were the main test elements for the control of allochthonous nutrient inputs. The scenario analysis revealed that reduction of phosphorus and nitrogen loads from diffused sources will have a marginal effect on controlling eutrophication if macrophyte growth is left uncontrolled. Scenarios employing macrophyte harvesting and sediment dredging have been evaluated for autochthonous nutrient input control. Sediment dredging alone has been shown to yield the most favorable conditions for water quality improvement in Mogan Lake. Further, control of diffuse pollution was an essential final step to achieve an acceptable long-term sustainable water quality improvement in the lake.
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Affoue Hortense, Kouame, Kouame Kouame Martin, Djirieoulou Kemomadjehi Claver i Boussou Koffi Charles. "ORGANIC POLLUTION INDEX IN THE EVALUATION OF THE QUALITY OF LAKE DOHOU, A SOURCE OF DRINKING WATER SUPPLY IN THE CITY OF DUEKOUE (WEST COTE DIVOIRE)". International Journal of Advanced Research 9, nr 12 (31.12.2021): 30–37. http://dx.doi.org/10.21474/ijar01/13872.
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The abiotic typology of the different sampling stations based on physico-chemical parameters and the assessment of the nutrient load and the relative contributions of the different nutrient sources to this surface water were analysed. Five physical and chemical parameters (temperature, dissolved oxygen, transparency, pH and conductivity) were measured in situ at each sampling campaign in Lake Dohou over a period of one year, once a month at seven (7) selected stations. Water samples were taken for subsequent determination of dissolved solids, biological oxygen demand for 5 days and nutrient salts (nitrite, nitrate, phosphate, ammonium).Thephysico-chemical characterisation revealed weakly mineralised water with average conductivities varying from 12.38 ±16.33 µS.cm-1 to 39.63 ±45.28 µS.cm-1 with high temperatures in the dry season. A hierarchical ascending classification (HAC) was used to group the stations into 3 groups. Group I (stations 6), due to its exposure to domestic discharges and leaching from agricultural land, is heavily loaded with organic matter and nutrients. The values of the pollution index express a high organic pollution at all the sampling stations. The water of Lake Dohou is highly loaded with organic matter and receives a very high amount of pollutant from the environment.
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Ghosh Roy, Subhomita, Charles F. Wimpee, S. Andrew McGuire i Timothy J. Ehlinger. "Responses of Bacterial Taxonomical Diversity Indicators to Pollutant Loadings in Experimental Wetland Microcosms". Water 14, nr 2 (16.01.2022): 251. http://dx.doi.org/10.3390/w14020251.
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Urbanization results in higher stormwater loadings of pollutants such as metals and nutrients into surface waters. This directly impacts organisms in aquatic ecosystems, including microbes. Sediment microbes are known for pollution reduction in the face of contamination, making bacterial communities an important area for bioindicator research. This study explores the pattern of bacterial responses to metal and nutrient pollution loading and seeks to evaluate whether bacterial indicators can be effective as a biomonitoring risk assessment tool for wetland ecosystems. Microcosms were built containing sediments collected from wetlands in the urbanizing Pike River watershed in southeastern Wisconsin, USA, with metals and nutrients added at 7 day intervals. Bacterial DNA was extracted from the microcosm sediments, and taxonomical profiles of bacterial communities were identified up to the genera level by sequencing 16S bacterial rRNA gene (V3–V4 region). Reduction of metals (example: 90% for Pb) and nutrients (example: 98% for NO3−) added in water were observed. The study found correlations between diversity indices of genera with metal and nutrient pollution as well as identified specific genera (including Fusibacter, Aeromonas, Arthrobacter, Bacillus, Bdellovibrio, and Chlorobium) as predictive bioindicators for ecological risk assessment for metal pollution.
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Ejike David Ugwuanyi, Zamathula Queen Sikhakhane Nwokediegwu, Michael Ayorinde Dada, Michael Tega Majemite i Alexander Obaigbena. "Review of emerging technologies for nutrient removal in wastewater treatment". World Journal of Advanced Research and Reviews 21, nr 2 (28.02.2024): 1737–49. http://dx.doi.org/10.30574/wjarr.2024.21.2.0520.
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The burgeoning global population and industrial activities have significantly increased the generation of wastewater laden with nutrients, posing severe environmental and public health concerns. Traditional wastewater treatment methods often fall short in effectively removing nutrients like nitrogen and phosphorus, leading to eutrophication of water bodies and endangering aquatic ecosystems. In response, emerging technologies for nutrient removal in wastewater treatment have gained traction in recent years, offering innovative and efficient solutions to mitigate nutrient pollution. This comprehensive review explores the latest advancements in nutrient removal technologies, encompassing biological, physical, and chemical processes. Biological treatment methods, including activated sludge, sequencing batch reactors (SBRs), and membrane bioreactors (MBRs), have been extensively studied and optimized for nutrient removal. Novel biofilm-based systems, such as moving bed biofilm reactors (MBBRs) and integrated fixed-film activated sludge (IFAS), have demonstrated enhanced nutrient removal capabilities and resilience to fluctuations in wastewater composition. Furthermore, the integration of advanced oxidation processes (AOPs) and membrane technologies has revolutionized nutrient removal from wastewater. AOPs, such as ozonation, ultraviolet (UV) irradiation, and photocatalysis, offer effective means to degrade recalcitrant organic pollutants and disrupt nutrient cycles. Membrane-based technologies, including reverse osmosis (RO), nanofiltration (NF), and forward osmosis (FO), enable selective nutrient removal and concentration, thereby producing high-quality effluent suitable for reuse or discharge into sensitive environments. Additionally, the review delves into emerging chemical treatment strategies, such as adsorption, precipitation, and ion exchange, for targeted removal of nutrients from wastewater streams. Advanced adsorbents and nanomaterials exhibit superior adsorption capacities and selectivity for nitrogen and phosphorus compounds, paving the way for cost-effective nutrient recovery and resource recycling. Moreover, the review highlights the importance of process optimization, system integration, and environmental sustainability in the development and deployment of emerging nutrient removal technologies. Life cycle assessments (LCAs) and techno-economic analyses provide valuable insights into the environmental footprint and economic viability of these innovative solutions, guiding decision-makers towards sustainable wastewater management practices. In conclusion, the synthesis of biological, physical, and chemical processes in emerging nutrient removal technologies holds great promise for addressing the challenges of nutrient pollution in wastewater treatment. Future research directions should focus on scalability, energy efficiency, and holistic approaches towards achieving water quality goals and fostering a circular economy.
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Cooper, Rachael Z., Sarina J. Ergas i Mahmood Nachabe. "Multi-Decadal Nutrient Management and Trends in Two Catchments of Lake Okeechobee". Resources 13, nr 2 (13.02.2024): 28. http://dx.doi.org/10.3390/resources13020028.
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Despite years of efforts to improve water quality, harmful algal blooms remain a chronic phenomenon, with devastating environmental, economic, and social impacts in many regions worldwide. In this study, we assessed the complexity of nutrient pollution attributed to harmful algal blooms in South Florida (USA) by analyzing 20 years of flow and nutrient data within two headwater basins in the Lake Okeechobee (LO) watershed. The study used an established advanced regression method, the Weighted Regression on Time, Discharge, and Season (WRTDS) method, as an analysis framework to examine the impact of nutrient management practices on water quality trends. The WRTDS method produced total phosphorus (TP) and total nitrogen (TN) concentration and flux trends, which were then compared with existing and historic nutrient management records within the basin. Results from this study highlight divergences in progress to improve water quality. Nutrient management practices only had a weak impact on TP and TN flux trends in one of the two basins, where TP flux decreased 2% per year, and TN flux decreased 0.1% per year. TP and TN flux increased in the second basin. Variances of improvement between the two basins are likely attributable to differences in contemporary point source loading and legacy nutrient pools from non-point source inputs 20 years or more before the analysis period. The long-lasting impacts of legacy nutrients also emphasize a need for investments in technologies and practices that can withdraw nutrients from enriched soil and water.
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Tonmanee, N., i N. Kanchanakool. "Agricultural diffuse pollution in Thailand". Water Science and Technology 39, nr 3 (1.02.1999): 61–66. http://dx.doi.org/10.2166/wst.1999.0137.
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Over the past two decades there have been a number of changes in Thailand, changes in the environment and quality of life for its people, changes in its communities and in the foundations of its economy. Before 1970, Thailand was a rural society in which local communities depended on the natural resources which surrounded them, and the national economy relied on the export of native crops. The sustainable use of resources was a fundamental aspect of rural life, people understood the interrelationships between the different components of their local environment and their activities which were defined by the need to protect their surrounding resources. Agriculture is the major profession and source of income for the rural poor. Land degradation and soil depletion result in low crop yields and pollution of the environment; soil erosion and landslides are found in Thailand. Nutrient uptake by crops and loss by leaching is much greater than the nutrients applied. Hence soils become less productive and it results in more land requirement for food production. Forest land declines rapidly in hilly watershed areas. Thailand is located in a tropical region and European countries are located in a temperate region. The climate is completely different, the temperature during summer in some European countries is probably almost the same as winter in Thailand. Not only is the climate in the two regions different, but land use and soil type are different also. These parameters have to be considered when studying the impact of agricultural diffuse pollution on the environment. Research studies on agricultural diffuse pollution in water resources in Thailand show that nutrient loads and pesticide residues still do not exceed the standard level. However, there was a trend showing the increase of N-NO3 in water resources, in short-term monitoring of nutrients in the east of Thailand between 1988-1990 and 1993-1995. The result showed the increase of N-NO3 from 1.60 ppm to 2.54 ppm in the same watershed and landuse areas. If the use of fertilizers and pesticides in agriculture is increased without due consideration, Thailand will face the same problem as European countries.
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Wang, X., T. Li, Q. Xu i W. He. "Study of the distribution of non-point source pollution in the watershed of the Miyun Reservoir, Beijing, China". Water Science and Technology 44, nr 7 (1.10.2001): 35–40. http://dx.doi.org/10.2166/wst.2001.0383.
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Nitrogen and phosphorus are major nutrients to cause eutrophication to degrade the water quality of the Miyun Reservoir, a very important drinking water source of Beijing in China. These are mainly from non-point sources. The watershed in Miyun County is selected as the study region with a total area of 1400 km2. Four typical monitoring catchments and two experimental units were used to monitor the precipitation, runoff, sediment yield and pollutant loading related to various land uses in the meantime. The results show that the total nutrient loss amount of TN and TP is 898.07 t/a, and 40.70 t/a, respectively, in which nutrient N and P carried by runoff is 91.3% and 77.3%, respectively. There is relatively heavier soil erosion at the northern mountain area whereas the main nutrient loss occurs near the northeast rim of the reservoir. Different land uses influence the loss of non-point source pollutants. The amount of nutrient loss from agricultural land per unit is the highest, nutrient loss from forestry is the second highest and that from grassland is the lowest. However, due to the variability of land use areas, agricultural land contributes the greatest amount of TP and forestry lands the greatest amount of TN.
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Han, P., K. Vijayaraghavan, S. Reuben, E. S. Estrada i U. M. Joshi. "Reduction of nutrient contaminants into shallow eutrophic waters through vegetated treatment beds". Water Science and Technology 68, nr 6 (1.09.2013): 1280–87. http://dx.doi.org/10.2166/wst.2013.361.
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One of the most effective mitigative approaches to eutrophication is the reduction of nutrient loading into water bodies. Bioremediation presents an economically viable and ecologically sustainable technology to nutrient pollution control taking advantage of the remarkable ability of plants and their associated microbial community to assimilate and remove nutrients from the environment. In this study, four emergent macrophytes (Cyperus haspan, Pandanus amaryllifolius, Pontederia cordata and Thalia geniculata) and two floating plants (Hygroryza aristata and Pistia stratiotes) were deployed in bank-side treatment beds and comparatively assessed for their remediative capabilities for nutrient control. P. stratiotes exhibited the highest removal efficiency for both nitrate and phosphate among the six plant species studied. Emergent macrophytes, P. amaryllifolius, C. haspan and P. cordata, were also found to be highly effective in nutrient uptake exhibiting removal efficiencies up to 100%. With the exception of T. geniculata, depletion of nutrients as a result of plant uptake significantly impeded the natural colonization of algae invariably leading to improvements in water quality in terms of turbidity and pH. Suppression of algae proliferation by T. geniculata was not preceded by a reduction in nutrient concentrations suggesting that T. geniculata may be directly inhibiting algal growth through allelopathy.
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McMahon, P. J. T. "The Impact of Marinas on Water Quality". Water Science and Technology 21, nr 2 (1.02.1989): 39–43. http://dx.doi.org/10.2166/wst.1989.0025.
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Four salt-water marinas were studied in an attempt to ascertain their impact on water quality. Analyses of water, sediment and biological samples showed no evidence of dissolved oxygen depletion or nutrient enrichment of the water column and no nutrient enrichment, organic pollution, toxic pollution or bacterial degradation of the sediments. Analyses of organotin compounds from antifouling residues were inconclusive due to problems in interpreting the results and comparing them with overseas results. The major impact was found to be the build-up of heavy metals (Pb, Cu, Zn, Hg) and petroleum hydrocarbons. The accumulated levels of these, however, were similar to those in other areas affected by human activity and were not indicative of significant water pollution. Nevertheless, water quality within marinas can be improved and guidelines for marina construction were developed based on the results of this study and a literature review.
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Xuan, Weidong, Chenggang Yang, Xiang Wu, Yiting Shao i Yu Bai. "A Numerical Model of the Pollutant Transport in Rivers with Multi-Layer Rigid Vegetation". Water 16, nr 10 (14.05.2024): 1397. http://dx.doi.org/10.3390/w16101397.
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River water pollution is a key environmental issue to human society. How to effectively simulate the flow velocity and pollution transport in a vegetated river can provide a theoretical basis for solving such problems. Based on previous experimental data, this article uses the lattice Boltzmann method and random displacement method to simulate the velocity distribution and nutrient transport in multi-layer rigid vegetated rivers. The simulation results indicate that incorporating the drag force of the vegetation into the model according to different vegetation layers can effectively simulate the velocity in a multi-layer vegetated river. Incorporating the turbulent diffusion and mechanical diffusion effects of nutrients caused by vegetation into the model can effectively simulate the effects of multi-layer vegetation on nutrient transport. This model can provide effective predictions of the flow velocity and pollution transport in multi-layer vegetation.
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Klages, Susanne, Claudia Heidecke, Bernhard Osterburg, John Bailey, Irina Calciu, Clare Casey, Tommy Dalgaard i in. "Nitrogen Surplus—A Unified Indicator for Water Pollution in Europe?" Water 12, nr 4 (22.04.2020): 1197. http://dx.doi.org/10.3390/w12041197.
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Pollution of ground-and surface waters with nitrates from agricultural sources poses a risk to drinking water quality and has negative impacts on the environment. At the national scale, the gross nitrogen budget (GNB) is accepted as an indicator of pollution caused by nitrates. There is, however, little common EU-wide knowledge on the budget application and its comparability at the farm level for the detection of ground-and surface water pollution caused by nitrates and the monitoring of mitigation measures. Therefore, a survey was carried out among experts of various European countries in order to assess the practice and application of fertilization planning and nitrogen budgeting at the farm level and the differences between countries within Europe. While fertilization planning is practiced in all of the fourteen countries analyzed in this paper, according to current legislation, nitrogen budgets have to be calculated only in Switzerland, Germany and Romania. The survey revealed that methods of fertilization planning and nitrogen budgeting at the farm level are not unified throughout Europe. In most of the cases where budgets are used regularly (Germany, Romania, Switzerland), standard values for the chemical composition of feed, organic fertilizers, animal and plant products are used. The example of the Dutch Annual Nutrient Cycling Assessment (ANCA) tool (and partly of the Suisse Balance) shows that it is only by using farm-specific “real” data that budgeting can be successfully applied to optimize nutrient flows and increase N efficiencies at the farm level. However, this approach is more elaborate and requires centralized data processing under consideration of data protection concerns. This paper concludes that there is no unified indicator for nutrient management and water quality at the farm level. A comparison of regionally calculated nitrogen budgets across European countries needs to be interpreted carefully, as methods as well as data and emission factors vary across countries. For the implementation of EU nitrogen-related policies—notably, the Nitrates Directive—nutrient budgeting is currently ruled out as an entry point for legal requirements. In contrast, nutrient budgets are highlighted as an environment indicator by the OECD and EU institutions.
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Urrestarazu, Miguel, Isidro Morales, Tommaso La Malfa, Ruben Checa, Anderson F. Wamser i Juan E. Álvaro. "Effects of Fertigation Duration on the Pollution, Water Consumption, and Productivity of Soilless Vegetable Cultures". HortScience 50, nr 6 (czerwiec 2015): 819–25. http://dx.doi.org/10.21273/hortsci.50.6.819.
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The management of water and nutrient ions, such as nitrate, has been studied extensively in recent decades. Increasingly efficient models have been developed for the use of water and nutrients through the automation of fertigation techniques. The application of a fertigation volume for a duration four times longer than applied on the control was evaluated. In Almería (Spain), one pepper crop and two tomato crops—with and without grafting—were grown between Oct. 2013 and June 2014 in a soilless system with a coir substrate. The effects on root growth, plant growth, production, and quality were measured. The following parameters for the fertigation of the nutrient solution and drainage were recorded: % drainage volume, electrical conductivity (EC) of the nutrient solution, pH, and concentration of nitrates and potassium. The absorption of potassium and nitrate, and the nitrate emissions of the drainage were estimated. The results showed an increase in the root volume and an improved distribution in the cultivation unit for the treatment application in the pepper crop. Slowing the applied fertigation improved the absorption of water and nitrates, and the production in the ungrafted tomato and pepper crops, while the grafted tomato crop was unaffected. Nitrate emissions were lower in the evaluated treatment of the pepper and ungrafted tomato crops. The fruit quality parameters were unaffected.
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Burke, S., L. Heathwaite, P. Quinn, S. Merrett, P. Whitehead, N. Preedy, D. Lerner i A. Saul. "Strategic management of non-point source pollution from sewage sludge". Water Science and Technology 47, nr 7-8 (1.04.2003): 305–10. http://dx.doi.org/10.2166/wst.2003.0703.
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In the UK, the recycling of sewage sludge to land is expected to double by 2006 but the security of this route is threatened by environmental concerns and health scares. Strategic investment is needed to ensure sustainable and secure sludge recycling outlets. At present, the security of this landbank for sludge recycling is determined by legislation relating to nutrient rather than potentially toxic elements (PTEs) applications to land - especially the environmental risk linked to soil phosphorus (P) saturation. We believe that not all land has an equal risk of contributing nutrients derived from applications to land to receiving waters. We are currently investigating whether it is possible to minimise nutrient loss by applying sludge to land outside Critical Source Areas (CSAs) regardless of soil P Index status. Research is underway to develop a predictive and spatially-sensitive, semi-distributed model of critical thresholds for sludge application that goes beyond traditional “end-of-pipe” or “edge-of-field” modelling, to include hydrological flow paths and delivery mechanisms to receiving waters from non-point sources at the catchment scale.
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Chu, Xiaodong, Daishe Wu, Hao Wang, Fangwen Zheng, Cheng Huang i Liang Hu. "Spatial Distribution Characteristics and Risk Assessment of Nutrient Elements and Heavy Metals in the Ganjiang River Basin". Water 13, nr 23 (28.11.2021): 3367. http://dx.doi.org/10.3390/w13233367.
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The pollution of water bodies by nutrients and heavy metals can lead to a loss of biodiversity, environmental degradation, and harm to human health. During the two-month monitoring period (e.g., December 2019 to January 2020), variables such as trace metals (e.g., Cu, Zn, As, and Cr), nutrients (e.g., NH4+-N, TN, and TP), water temperature, pH value, dissolved oxygen (DO), chemical oxygen demand (COD) and five-day biochemical oxygen demand (BOD5) were measured at 102 monitoring points in the main stream and tributaries of the Ganjiang River in the Poyang Lake Basin. A variety of multivariate statistical techniques, including cluster analysis (CA), principal component analysis (PCA), and correlation analysis, were used to conduct risk assessments and source analyses of the nutrient elements and heavy metals in the Ganjiang River system. The results show that although the Ganjiang River Basin is polluted by human activities, its water chemistry characteristics and trace metal and nutrient elements concentrations were better than the national standards. Through principal component analysis, the water pollution sources could be divided into urban sewage, agricultural activities, industrial activities, and the sources of industrial activities and transportation activities. The comprehensive risks of noncarcinogens (Hc) and comprehensive risks of carcinogens (Rc) for adults and children due to drinking water indicated that the risk from drinking water for the children in the basin was greater than that for adults, and that the Hc for adults and children was acceptable. However, the Rc for adults and children was slightly higher than the acceptable values. This study provides a reference for the fine control of the environmental water pollution sources in the Ganjiang river basin and health risk assessments in the basin, which are of great significance for improving the environmental water quality standards in the river basin and for reducing the risk of carcinogenesis.