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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
61

Paviršinių nuotekų charakterizavomo tyrimai metalo laužo įmonėje / Pre-investigation of stormwater quality at metals scrap processing PLANT

Žimančiūtė, Jurgita 16 June 2005 (has links)
In the Master’s Thesis “Pre-investigation of Stormwater Quality at Metals Scrap Processing Plant” the literature review of 136 sources was performed with the focus on storm water pollution, physical and chemical properties of specific pollutants, origins of the pollution and pathways of the pollutants transport to the environment. Types of industrial storm water samples and sampling methodologies are described as well. Raprinfall data calculation are performed for the design of industrial storm water collection and treatment systems. The comprehensive analyses of storm water treatment are done. The experimental part of the work was carried out at the metal scrap processing industry with paved and unpaved aeries of the surfaces. During the research the industrial storm water screening characterisation was done at different locations of the whole territory. The treatment technology, including the sedimentation tank, retention tank and filtration trench was selected and calculated for the treatment of storm water of the investigated industry. The generalized conclusions and results of the work can be useful for state institutions, research institutions and the enterprises engaged in storm water management.
62

Avaliação da remoção de material particulado em canal raso gramado

Shinzato, Alexandre Hideki 10 April 2015 (has links)
Submitted by Izabel Franco (izabel-franco@ufscar.br) on 2016-09-27T14:11:10Z No. of bitstreams: 1 DissAHS.pdf: 2312692 bytes, checksum: c2ebb789fa7e739eba3f96c03b8c245a (MD5) / Approved for entry into archive by Ronildo Prado (ronisp@ufscar.br) on 2016-10-03T19:41:52Z (GMT) No. of bitstreams: 1 DissAHS.pdf: 2312692 bytes, checksum: c2ebb789fa7e739eba3f96c03b8c245a (MD5) / Approved for entry into archive by Ronildo Prado (ronisp@ufscar.br) on 2016-10-03T19:42:02Z (GMT) No. of bitstreams: 1 DissAHS.pdf: 2312692 bytes, checksum: c2ebb789fa7e739eba3f96c03b8c245a (MD5) / Made available in DSpace on 2016-10-03T19:50:38Z (GMT). No. of bitstreams: 1 DissAHS.pdf: 2312692 bytes, checksum: c2ebb789fa7e739eba3f96c03b8c245a (MD5) Previous issue date: 2015-04-10 / Não recebi financiamento / The study conducted examined the sediment removal behavior for a lawn channel built full-scale, 100 m in length, slope of 2% and wide base of 0.7 m in the Federal University of São Car them, San Carlos - SP. For this analysis, we simulated runoff for three volumes of downloads 5; 7; 10 m³, represented each with their respective hydrograph and blade height by passing the flood wave. These flows were mixed with the particulate material produced from the local ground of the campus area, sieved to smaller than 75 micron, which is used for varying the initial concentration for tests. The experimental data were fit to a model first order decay, Meira optimum slug flow in through non-linear regression using decay kinetic parameters (k d) and equilibrium concentration (C *). Fractions removed and the mathematical adjustment were evaluated and executed for each single event along the length of the lawn channel monitored in 26 positions. The peak of the hydrograph was investigated in the range of 11 ± 2 L / s and time base (tb) determined at the unloading point on the channel varied from 15, 25 and 35 minutes. The transit time in the channel (tT) was approximately 10.5 ± 2.5 m, corresponding to 0.14 ± speed 0,02 m / s. The maximum efficiency of particulate matter removing over the lawn channel length ranged from 47 to 81% in 20-90 m positions. Whereas all concentrations of investigates, it was found that for 15 minutes tB, the average maximum efficiencies were on the order of 64 ± 3% to ± 26 position of 31 m. TB to 25 minutes the average maximum were of the order of 73 ± 3% to 59 ± 24 m positions. Finally, for 35 minutes tB the average maximum efficiencies were obtained in the range of 65 ± 3% in the 73 ± 15 m positions. The ratio tb / tT correlated 0.98 with the position of maximum efficiency. The maximum removal positions are related to the decay constant (Kd). It was found that 70% of the values of the decay constant (Kd) is between 0.005 and 0.015 s-1, and to disregard the hydrograph represented by tB 15 minutes, 90% of the data is contained in it Halftone 0.005 Kd ≤ ≤ 0.015 s-1 and 85% in the range 0.007 ≤ 0.012 ≤ Kd s-1. It was identified direct and proportional relation of the equilibrium concentration (C *) and initial concentration (Co). / O estudo desenvolvido analisou o comportamento de remoção de sedimento para um canal gramado construído em escala real, 100m de extensão, declividade de 2% e largura de base de 0,7m, localizado na Universidade Federal de São Carlos, São Carlos - SP. Para tal análise, foram simulados escoamentos superficiais para três volumes de descarregamentos: 5; 7; 10m³, representados cada um com seu respectivo hidrograma e altura de lâmina pela passagem da onda de cheia. Estes escoamentos foram misturados com o material particulado produzido a partir do solo local da região do campus, peneirado para dimensões menores que 75μm, o qual foi utilizado para variação da concentração inicial para os ensaios realizados. Os dados experimentais foram ajustados a um modelo de decaimento de primeira ordem, em escoamento ideal pistonado por meio de regressão não linear, usando os parâmetros cinéticos de decaimento (kd) e de concentração de equilíbrio (C*). As frações removidas e o ajuste matemático foram avaliados e realizados para cada evento isolado, ao longo do comprimento do canal gramado e monitorados em 26 posições. O pico dos hidrogramas investigados foi da ordem de 11±2L/s, e o tempo de base (tB) determinado no ponto de descarregamento no canal variou de 15, 25 e 35 minutos. O tempo de trânsito no canal (tT) foi da ordem de 10,5±2,5 minutos, correspondente à velocidade de 0,14±0,02m/s. A eficiência máxima de remoção de material particulado ao longo do comprimento do canal gramado variou de 47 a 81% em posições de 20 a 90m. Considerando todas as concentrações investigadas, verificou-se que para tB de 15 minutos, a média das máximas eficiências foram da ordem de 64±3% para posição de 31±26m. Para tB de 25 minutos a média das máximas foram da ordem de 73±3% para posições de 59±24m. Finalmente, para tB de 35 minutos a média das máximas eficiências obtidas foram da ordem de 65±3% nas posições de 73±15m. O quociente tB/tT apresentaram correlação de 0,98 com a posição de máxima eficiência. As posições de máxima remoção estão relacionadas à constante de decaimento (kd). Verificou-se que 70% dos valores da constante de decaimento (kd) estão entre 0,005 e 0,015 s-1, sendo que ao desconsiderar o hidrograma representado por tB de 15 minutos, 90% dos dados estão contidos no intervalo 0,005 ≤ kd ≤ 0,015s-1 e 85% no intervalo 0,007 ≤ kd ≤ 0,012s-1. Foi identificada relação direta e proporcional da concentração de equilíbrio (C*) e concentrações iniciais (Co).
63

Sura sulfatjordar och vattenkvalitet Vattenmätningar från Vörå å 1969–2017 / Acid sulphate soils and water quality Water data from Vörå å 1969–2017

Hagenby, John January 2018 (has links)
Sura sulfatjordar (SSJ) bildas på tidigare havsbottnar med sulfidhaltiga sediment som med landhöjningen har lyfts upp ur havet och genom grundvattensänkande aktiviteter  exponerats för syre. Vörå å är ett vattendrag  i västra Finland som är kraftigt SSJ-påverkat. Närings-, trafik- och miljöcentralen i Österbotten har gjort vattenmätningar i Vörå å i flera decennier och syftet med detta arbete var att strukturera, beskriva och tolka tidigare obehandlade data från vattenmätningar som gjorts mellan 1969 och 2017 och därmed synliggöra årstidsvariationer och förändringar i vattnets kemiska sammansättning över tid. Vattenkvaliteten i Vörå å var allra sämst under höst och vår: pH <5, höga sulfathalter och konduktivitet om 25–100 mS/m.  Suspenderat material och turbiditet var som högst i april medan pH, konduktivitet, järnhalt och COD var som högst under sommaren. Variationerna i vattnets kemiska sammansättning var minst under våren och störst under sommaren då flera variabler uppvisade en mycket stor spridning. I slutet av mätperioden uppvisade många variabler en liten bättring och vad denna beror på är oklart. I och med klimatförändringar har årsmedeltemperaturerna i Finland stigit vilket skulle kunna tänkas påverka tiden för högflöden. Det finns tecken i datan som tyder på sådana förändringar sedan 1970-talet. Metallmätningar som gjorts under 2000-talet jämfördes mot bakgrundsvärden, vissa uppvisade förhöjda värden. / Acid sulphate soils (ASS) form in sulphide bearing marine sediments that have been exposed to atmospheric oxygen caused by eustatic uplift and draining of cultivated fields. The river Vörå å, in western Finland, is a small stream that is severely affected by ASS. Finnish authorities have during decades sampled and analysed the water, but the data has not been interpreted. The objective of this study was to structure, describe and interpret previously untreated analyses data of the water samples from the years 1969 to 2017. Wa-ter quality was in general very bad and the worst situations occurred during springs and late autumns with pH <5, high sulphate concentrations and EC between 25–100 mS/m. Suspended solids and turbidity peaked in April while pH, EC, iron concentration and COD were highest during the summer. The variations in the chemical composition of the water were lowest during the spring and most widespread during the summer. At the end of the measurement period, many variables showed a slight improvement, the reason for this is unclear. Due to climate change the mean temperatures in Finland have increased, this may possibly affect the timing for snow melt in the spring and the time for flooding during the autumn. There are signs in the data indicating such changes. Metal concentra-tions from samples collected since 2005/2010 were compared with regional background values. Some metals demonstrated high concentrations.
64

Distribuição espacial e temporal de sólidos em suspensão nos afluentes e reservatório da Usina Hidrelétrica Barra dos Coqueiros - GO / Spatial and temporal analysis of solid matter in reservoir of Hydroeletric plant in Barra dos Coqueiros - Goiás-Brazil

BRAGA, Celso de Carvalho 01 March 2012 (has links)
Made available in DSpace on 2014-07-29T14:39:37Z (GMT). No. of bitstreams: 1 Dissertacao Celso de Carvalho Braga.pdf: 3312309 bytes, checksum: f978b2519d34cde7af31bff47e8526ea (MD5) Previous issue date: 2012-03-01 / The construction of reservoirs for hydroelectric generates various environmental impacts, for instance, changes in the displacement and the concentration of suspended solids, thus causing changes in the fauna and flora of the water. The survey of suspended solids in a determined watershed is important to make correct decisions regarding the planning for a bowl, because the amount of solids is directly related to the land use. The problems caused by suspended solids include erosion, transport, deposition and compaction, in addition the suspended solids impair the quality of water for human consumption. This study aimed to analyze the spatial and temporal distribution of the concentration of suspended solids (CSS) in the main source of the lake in Barra dos Coqueiros and its influence on the life cycle of the reservoir from March 2011 to August 2011. To achieve the proposed goals, it was used methods such as calculating the concentration of suspended solids according to the proposal of Wetzel and Likens (1991), checking the levels of turbidity and water clarity in accordance with the proposal to Esteves (1998) and Tundisi (2008), calculating the flow of the sources of water by the method of floats as proposed by Ramos and Oliveira (2003), Palhares (2007), and calculating the total solid discharge of the main sources of water (of the) using simplified method of Colby (1964) that takes into consideration: liquid discharge, average speed, average depth, width and cross section measured concentration of suspended solids. According to the data, we reached the following conclusion: the concentration of suspended solids is well related to the data turbidity and water transparency. In the data collection reservoir of the rainy season, the concentration of suspended solids ranged from 7,5 to 30,5 mgL-1 and greater than the collection of the dry period, which ranged from 0,25 to 7,5 mgL-1. The same thing happens to the water transparency using a Secchi disk that ranged from 0,16 to 0,30 meters in the rainy season and 1,40 to 3,50 meters in the dry season. As for turbidity, the indices found shows that the reflectance of light in a rainy period ranged from 51 to 72 NTU, whereas the dry period ranged from 0 to 3,7 NTU. According to the evaluation of the spatial and temporal distribution of suspended solids concentration of the main sources of water in the reservoir of Barra dos Coqueiros, the main lake stands out among the sources analyzed, due to the higher concentration of suspended solids, ranging from 2,5 mgL-1 in the dry season to 14,5 mgL-1 in the rainy season. / A construção de reservatórios para usinas hidrelétricas geram impactos ambientais diversos, como, por exemplo, mudanças no deslocamento e concentração de sólidos em suspensão, ocasionando assim mudanças na fauna e flora aquáticas. O estudo dos sólidos em suspensão de uma determinada bacia hidrográfica é importante para que se possam tomar decisões corretas quanto ao planejamento de atividades de uma bacia, pois a quantidade de sólidos está diretamente associada ao uso da terra. Os problemas gerados pelos sólidos em suspensão vão desde a erosão, transporte, deposição e compactação, além de que os sólidos em suspensão prejudicam a qualidade da água para o consumo humano. O presente trabalho teve por objetivo analisar a distribuição espacial e temporal da concentração de sólidos em suspensão (CSS) nos principais afluentes e lago da UHE Barra dos Coqueiros, e sua influência na vida útil do reservatório no período de março a agosto de 2011. Os métodos utilizados para alcançar os objetivos propostos foram: calcular a concentração de sólidos em suspensão de acordo com a proposta de WETZEL E LIKENS (1991), verificar os níveis de turbidez e transparência da água de acordo com a proposta de ESTEVES (1998) e TUNDISI (2008), calcular a vazão dos afluentes pelo método de flutuadores, de acordo com a proposta de RAMOS e OLIVEIRA (2003), PALHARES (2007), e calcular a descarga sólida total dos principais afluentes pelo método simplificado de COLBY (1964) que leva em consideração: descarga líquida, velocidade média, profundidade média, largura da seção transversal e concentração medida de sólidos em suspensão. De acordo com os dados obtidos, chegou-se à seguinte conclusão: que a concentração de sólidos em suspensão tem boa relação com os dados de turbidez e transparência da água. Na coleta de dados do reservatório do período chuvoso, a concentração de sólidos em suspensão variou de 7,5 a 30,5 mgL-1, sendo maior que na coleta do período seco, que variou de 0,25 a 7,5 mgL-1. O mesmo acontece com transparência de água utilizando o disco de Secchi que variou de 0,16 a 0,30 metros no período chuvoso e de 1,40 a 3,50 metros no período seco. Quanto à turbidez, os índices encontrados mostram que a refletância da luz no período chuvoso variou de 51 a 72 NTU, enquanto no período seco variou de 0 a 3,7 NTU. Quanto à avaliação da distribuição espacial e temporal da concentração de sólidos em suspensão dos principais afluentes do reservatório da UHE Barra dos Coqueiros o Córrego Matriz se destaca entre os afluentes analisados, por apresentar maiores concentrações de sólidos em suspensão, variando de 2,5 mgL-1 no período seco a 14,5 mgL-1 no período chuvoso.
65

Vliv termické dezintegrace kalu na jeho další zpracování / Dependence of Sludge Thermal Pre-treatment on its Dewatering

Žerava, Zdeněk January 2010 (has links)
The first part of the thesis is focused on the problems related to sludge and evaluates sludge disposal from waste treatment plants. The thesis mentions factors influencing method selection of sludge disposal as well as it compares sludge disposal in the Czech Republic and in the other states of the EU. It describes a complete waste treatment line and sludge disposal in the area of sludge treatment and disposal. It deals with sludge disintegration and describes the most effective methods of disintegration. The second part of the thesis describes an experimental part of disintegration of waste treatment sludge. An experiment was conducted in the school laboratory in a way of thermal disintegration in the double-surface pressure tank. The disintegration was conducted to temperatures of 60 °C, 90 °C, 120 °C, 150 °C, and 180 °C. We monitored dependence of the sludge dry residue content on disintegration temperature as well as content of suspended solids in liquid fraction (FUGAT). It was possible to choose optimal temperature of disintegration in accordance with processed results.
66

Vliv specifické spotřeby flokulantu na odvodnitelnost čistírenského kalu / Dependence of Sludge Dewatering efficiency on amount of flocculant

Volejník, Tomáš January 2008 (has links)
The target of the first part of this diploma thesis is focused on the problems relating to the sludge production from the wastewater treatment plant and subsequent sludge treatment. Wastewater treatment plant and individual processes from the sludge management are described. The process of the sludge dewatering is described more extensively. Various methods of the dewatering and materials balance are described, too. The second part of this thesis is based on the experiment which took place on wastewater treatment plant Tetčice. The influence of the polymeric organic flocculant dosing on the sludge dewatering was monitored by this experiment. Dependence of the sludge dry matter and filtrate suspended solids content on the specific amount of flocculant was evaluated from experiment’s outputs. Using materials balance and outputs of the experiment, economical balance was made. It made possible to choose the most economic and technologically optimal way of the sludge dewatering on wastewater treatment plant Tetčice.
67

Vliv termické dezintegrace kalu na jeho další zpracování / Dependence of Sludge Thermal Pre-treatment on its Dewatering

Žerava, Zdeněk January 2010 (has links)
The first part of the thesis is focused on the problems related to sludge and evaluates sludge disposal from waste treatment plants. The thesis mentions factors influencing method selection of sludge disposal as well as it compares sludge disposal in the Czech Republic and in the other states of the EU. It describes a complete waste treatment line and sludge disposal in the area of sludge treatment and disposal. It deals with sludge disintegration and describes the most effective methods of disintegration. The second part of the thesis describes an experimental part of disintegration of waste treatment sludge. An experiment was conducted in the school laboratory in a way of thermal disintegration in the double-surface pressure tank. The disintegration was conducted to temperatures of 60 °C, 90 °C, 120 °C, 150 °C, and 180 °C. We monitored dependence of the sludge dry residue content on disintegration temperature as well as content of suspended solids in liquid fraction (FUGAT). It was possible to choose optimal temperature of disintegration in accordance with processed results.
68

Effects of Precipitation Patterns on Sediment, Nutrient, and Biofilm Dynamics in an Acid Mine Drainage Stream

Brancho, Jennie 04 June 2019 (has links)
No description available.
69

Surface water quality in canals in An Giang province, Viet Nam, from 2009 to 2016

Nguyen, Hong Thao Ly, Nguyen, Thanh Giao 27 February 2019 (has links)
The present study evaluates the surface water quality in the canals of An Giang province in the period from 2009 to 2016. The results showed that surface water of the canals was contaminated by organic matter and microorganisms which makes it not suitable for water supply and conservation of aquatic life. The water quality parameters such as dissolved oxygen (DO), biological oxygen demand (BOD), total suspended solids (TSS), orthophosphate (P-PO43-) and coliforms levels in the wet season were found to be higher than those in the dry season. The problem of organic and microorganic pollution over a long period of time without solutions leads to declines in water quality and then quantity as well. Agriculture is the main activity contributing to pollution of surface water in interior canals along with the activities of daily life, industry and services. This causes pollution of the surface water on Hau River due to its exchange of water with the connected canals. Good agricultural practices should be implemented to limit the pollution of surface water resources of the Mekong Delta. / Nghiên cứu này nhằm đánh giá diễn biến chất lượng nước mặt trong các kênh rạch nội đồng của tỉnh An Giang trong giai đoạn 2009 – 2016. Kết quả cho thấy nước mặt tại các kênh rạch nội đồng đã ô nhiễm hữu cơ và vi sinh vật. Nguồn nước không phù hợp cho mục đích cấp nước sinh hoạt và bảo tồn thực vật thủy sinh. Các chỉ tiêu như hàm lượng oxy hòa tan (DO), nhu cầu oxy sinh hóa (BOD), tổng chất rắn lơ lửng (TSS), orthophosphate (P-PO43-) và coliforms trong mùa mưa cao hơn mùa khô. Vấn đề ô nhiễm hữu cơ và vi sinh vật diễn ra trong thời gian dài và chưa có giải pháp xử lý làm cho chất lượng nước suy giảm dẫn đến suy giảm về trữ lượng. Nông nghiệp là hoạt động chính góp phần làm ô nhiễm nguồn nước mặt trong các kênh rạch nội đồng bên cạnh các hoạt động sinh hoạt, công nghiệp và dịch vụ. Điều này dẫn đến nước mặt trên sông Hậu cũng có đặt tính ô nhiễm tương tự do trao đổi nước với các kênh rạch nội đồng. Thực hành sản xuất nông nghiệp thân thiện môi trường cần sớm được triển khai để hạn chế ô nhiễm nguồn nước mặt quan trọng của khu vực đồng bằng sông Cửu Long.
70

Wastewater treatment in constructed wetlands : Effects of vegetation, hydraulics and data analysis methods

Bodin, Hristina January 2013 (has links)
Degradation of water resources has become one of the most pressing global concerns currently facing mankind. Constructed Wetlands (CWs) represent a concept to combat deterioration of water resources by acting as buffers between wastewater and receiving water bodies. Still, constructing wetlands for the sole purpose of wastewater treatment is a challenging task. To contribute to this research area, the fundamental question raised in this doctorate thesis was: how do factors such as vegetation and residing water movements (hydraulics) influence wastewater treatment in CWs? Also, effects of different data analysis methods for results of CW hydraulics and wastewater treatment were investigated. Research was focused on  phosphorus (P), ammonium-nitrogen (NH4+-N) and solids (TSS) in wastewater and o n P in macrophyte biomass. Studies were performed in pilot-scale free water surface (FWS) CW systems in Kenya (Chemelil) and Sweden (Halmstad) and as computer simulations. Results from the Chemelil CWs demonstrated that meeting effluent concentration standards simultaneously for all water quality parameters in one CW was difficult. Vegetation harvest, and thus nutrient uptake by young growing macrophytes, was important for maintaining low effluents of NH4+-N and P, especially during dry seasons. On the other hand, mature and dense vegetation growing for at least 4 months secured meeting TSS standards. Phosphorus in above-ground green biomass accounted for almost 1/3 of the total P mass removal, demonstrating high potential for P removal through macrophyte harvest in CWs. Also, results suggested that harvest should be species-specific to achieve high P removal by macrophytes and overall acceptable wastewater treatment in CWs. Still, different methods to estimate evapotranspiration (ET) from the Chemelil CWs showed that water balance calculations greatly impacted estimations of wastewater treatment results. Hydraulic tracer studies performed in the Chemelil and Halmstad CWs showed that mature and dense emergent vegetation in CWs could reduce effective treatment volumes (e-values), which emphasized the importance of regulating this type of vegetation. Also, it was shown that hydraulic tracer studies with lithium chloride performed in CWs with dense emergent vegetation had problems with low tracer recoveries. This problem could be reduced by promoting the distribution of incoming tracer solution into the CW using a barrier near the CW inlet pipe. Computer simulation results showed that the choice of tracer data analysis method greatly influenced quantifications of CW hydraulics and pollutant removal. The e-value could be 50% higher and the pollutant removal 13% higher depending upon used method. Moreover, unrealistic evalues (above 100%) in published literature could to some extent be explained by tracer data analysis method. Hence, to obtain more reliable hydraulic data and wastewater treatment results from CWs, more attention should be paid to the choice of tracer data analysis method. / Konstruerade våtmarker representerar ett koncept för möjligheten att nå en hållbar vattenresurshantering genom att agera som ”filter” mellan föroreningskälla och viktiga vattenresurser såsom sjöar och hav. Mycket kunskap saknas däremot om hur man konstruerar våtmarker med en optimal och pålitlig vattenreningskapacitet. Den här avhandlingen undersöker därför hur vegetation och vattnets väg genom våtmarken (hydrauliken) påverkar avloppsvattenrening i våtmarker. Dessutom undersöktes hur valet av dataanalysmetod av insamlad data påverkar resultaten. Studier genomfördes i Kenya och Sverige i experimentvåtmarker (ca. 40-60 m2) och inkluderadedatainsamling av vattenkvalité, hydraulik (spårämnesexperiment) samt biomassa och fosfor i biomassan av två olika våtmarksväxter. Dessutom genomfördes datorsimuleringar. Resultaten från Kenya visade att växtskörd och efterföljande näringsupptag av nyskördade växter var viktig för att uppnå låga utgående koncentrationer av fosfor och ammonium i en tropisk våtmark, speciellt under torrsäsongen. Däremot var en välutvecklad och tät vegetation viktig för reningen av partiklar. Fosfor i grön växtbiomassa representerade cirka 1/3 av våtmarkernas totala fosforrening, vilket påvisade potentialen i att genom skörd ta bort fosfor från avloppsvatten m.h.a. konstruerade våtmarker. Resultaten pekade också på att skörden bör vara art-specifik för att uppnå en hög fosforrening och generellt bra vattenreningsresultat. Dock visade olika beräkningsmetoder att vattenbalansen i en tropisk våtmark markant kan påverka vattenreningsresultaten. Resultaten från spårämnesexperimenten demonstrerade att den effektiva våtmarksvolymen för vattenrening blev mindre vid hög täthet av övervattensväxter. Detta pekade på att regelbunden växtskörd var viktig för att uppnå god vattenrening i våtmarker. Experiment med spårämnet litium visade att man kan få felaktiga resultat p.g.a. att en del spårämne fasthålls på botten i våtmarken om denna har mycket övervattensväxter. Därför bör spridningen av spårämnet i sådana våtmarker underlättas m.h.a. en spridningsbarriär nära inloppsröret. Simuleringar visade också att valet av dataanalysmetod av spårämnesdata starkt kan påverka resultaten och därmed också vår tolkning av en våtmarks hydraulik och reningskapacitet. Den effektiva volymen kunde vara 50% högre och reningseffekten 13% högre beroende på vilken metod som användes. Likaså kan valet av dataanalysmetod ha bidragit till överskattade och orealistiska effektiva volymer (över 100%) i artiklar publicerade de senaste 25 åren. Genom att fokusera mer på valet av dataanalysmetod och t.ex. jämföra resultaten från två olika metoder kan man minimera risken för bristfälliga resultat och därmed felaktiga slutsatser om en våtmarks vattenreningskapacitet.

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