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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.
891

Analysis of three wetland medicinal plants: Centella asiatica, Cyperus longus and Typha capensis found in the Western Cape Province of South Africa.

Saibu, Olusola Surajudeen January 2017 (has links)
Magister Scientiae (Biodiversity and Conservation Biology) / South Africa is recognised worldwide for its rich diversity of plants, many of which have been used in ethno-medicine. However, the use of wetland plant species in ethno-medicine required further investigations. This research is aimed at investigating three wetland medicinal, plant species, Centella asiatica, Cyperus longus and Typha capensis based on their geographical, seasonal, mineral nutrient (Fe, Mn, Ca, Mg, K and Na) and secondary metabolite characteristics. Samples of each species were collected from Grabouw, Kelderhoff, Kenilworth, Pringle Bay, University of the Western Cape (UWC) and Worcester within the Western Cape Province of South Africa. Specimen and soil collections were carried out during autumn, spring, summer and winter of 2014. Both plant and soil samples were acid digested and mineral nutrient concentrations in the samples were analysed using an atomic absorption spectrometer (AAS). Secondary metabolites were determined using analytical TLC on normal phase Merck-Silva gel coated aluminium plates as well as by using HPLC separation from crude extracts of C. asiatica, C. longus and T. capensis using LC-MS hardware from Agilent. The elemental analysis of soil samples showed that Ca, K, Mg, Mn and Zn concentrations were predominantly low. Soil mineral concentrations increased progressively from inland (Worcester) towards the coastland in the south (Pringle Bay). Calcium and sodium concentrations, in particular, were higher in soil samples obtained from Grabouw (inland south) and decreased northward towards Worcester. Comparatively, plant mineral concentrations were generally higher than soil concentrations. The high concentration of some of these essential elements, in selected plants is an indication that these plant species could be a good source of essential elements. High concentrations of phytochemicals were found in Centella asiatica during winter, while Cyperus longus and Typha capensis exhibited high concentrations during autumn indicating variation in respect of season. Consequently, harvesting of the studied plants should be done at the season with a relatively high phytochemical concentration. Studies are needed to investigate the extent of pesticide or herbicide contamination in wetland plants to protect the health of users. The LC-MS analyses of the three study species showed that seasonal variation affects metabolite constituents and moreover that these metabolite constituents differ from one locality to another. The seasonal variation of the elements in the studied medicinal plants justified the importance of harvesting seasons in the optimal utilization of the studied plants for medicinal purpose. s, for C. asiatica, anti-bacterial treatments for C. longus and fertility enhancement and birth control for T. capensis.
892

Habitatové preference ptáků na mokřadech SV Čech a optimalizace managementu v připravované přírodní památce Sedmihorské slatiny

ŠŤASTNÝ, Vojtěch January 2018 (has links)
The diploma thesis deals with the influence of the stated environmental factors on the composition of bird communities and density of particular bird species in selected wetlands of northeastern Bohemia. Then it studies influence of these factors on birds' diversity and proportion of specially protected species according to the Czech law (the Act No. 114/1992 Coll.). Lastly, it points out the use of these results in practical nature conservation. In the introductory comment of the thesis there is described the character of the study area and subsequently opportunities for implementation of the study results in conservation of study localities that will lead to increase of habitats quality for wetland bird communities. Detailed optimization of habitat conditions is suggested for the locality Sedmihorské slatiny that's establishment as a natural monument is prepared.
893

Field Development and Performance Evaluation of a Constructed Wetland System in the Tropics

Hummel, Adelaide Pereira 08 November 2013 (has links)
This study is part of a project that was conducted by Florida International University (FIU), which designed, built, and characterized a constructed wetland (CW) wastewater treatment system in El Salvador, Central America. This study focuses on the detailed performance of a field-scale CW in the tropics, consisting of a subsurface flow wetland (SSF) and a surface flow wetland (SF). The SSF had a total area of 151.2 sq. m., filled with gravel and planted with Phragmites, Thalia, and Brachiaria, along three independent cells operating with a flow in parallel and receiving the influent domestic wastewater from a facultative lagoon and preceded the SF. The SF was a shallow open basin containing alternating regions of open water (195 sq. m. total) with submerged aquatic plants (Elodea) and regions of shallower water (605 sq. m. total) filled with emergent wetland vegetation (Typha, Thalia, and Cyperus). The design, construction, startup and operation phases of the field scale CW in that tropical setting are thus described with detail, including both SSF and SF characterization of influent and effluents. The SSF average hydraulic detention times during the wet and dry season were 2 days ± 0.9 days and 4 days ± 0.4 days, respectively; and the SF average hydraulic detention times during the wet and dry season were 20 days ± 11.1 days and 77 days ± 19.5 days, respectively. Brachiaria/Cyperus presented better results during the wet season with average BOD5 residuals of 36% ± 25%, and Thalia/Thalia during the dry season with average BOD5 residuals of 33% ± 22%. Phragmites/Typha presented better results during both seasons with average TSS residuals of 2% ± 3% (wet season), and 2% ± 2% (dry season). Residuals are also presented for COD, Oil & Grease, Total Fecal Coliform, Total Phosphorus, and Total Nitrogen. In addition, an assessment of the empirical models used in the design of the system is completed, having the EPA methodology as the preferred for BOD5 removal and three methodologies for TSS removal under tropical climate conditions. A comparison of the differences in treatment associated with each one of the selected plants and their combinations is also discussed. In summary, results strongly suggest that the CW system can effectively reduce contaminants in wastewater to levels that are comparable with the objective levels (i.e., secondary treatment levels).
894

Linking Organic Matter Dynamics to Management, Restoration, and Climate in the Florida Everglades

Regier, Peter 30 June 2017 (has links)
The Florida Everglades is a massive and highly managed subtropical wetland ecosystem, strongly influenced by anthropogenic control of freshwater distribution and highly susceptible to a changing climate, including rising sea-level and changes in temperature and rainfall. Shifting hydrologic regimes impact ecosystem function and biogeochemistry, which in turn control the sources, fate, and transport of organic matter. As a master environmental variable, it is essential to understand how organic matter dynamics will respond to changes in the balance between freshwater and saltwater associated with landscape-scale Everglades restoration efforts and climate change. The research comprising this dissertation improves current understanding of the linkages between organic matter and hydrology in the Everglades across a broad range of temporal and spatial scales. A range of research tools, including stable molecular biomarkers, water quality sensors, data synthesis and multivariate statistics were utilized. Biomarkers were used to track particulate organic matter mobilization in response to experimentally manipulated flows and provided initial evidence that sheet flow restoration can re-engineer landscape microtopography, influencing both ecosystem structure and organic matter inputs to Everglades National Park (ENP). Short-term and long-term temporal studies indicated the quantity and quality of dissolved organic carbon responds to changes in freshwater flow to marshes and mangrove forests in ENP, and that spatial patterns and trends are driven by a complex mixture of managed and natural surface water inputs (i.e., rainfall and water management inflows) as well as groundwater discharge. Application of climate scenario forecasting to relationships established between organic matter and hydrologic drivers predicted reductions in dissolved organic carbon export from ENP and changes in organic matter molecular composition. Furthermore, high-frequency measurements showed hydrologic connectivity of freshwater and estuarine organic matter pools at sub-monthly time-scales. In summary, the work presented here clearly indicates strong yet spatiotemporally complex relationships between changes in water and the sources and transport of organic carbon through the Everglades.
895

Transporte de CO2 em meio aquoso a partir da interface agua-ar / CO2 transport in aqueous medium from water-air interface

Lage, Euler Martins 16 December 2002 (has links)
Orientador: Ines Joeks / Tese (doutorado) - Universidade Estadual de Campinas, Instituto de Quimica / Made available in DSpace on 2018-08-11T21:07:38Z (GMT). No. of bitstreams: 1 Lage_EulerMartins_D.pdf: 1438659 bytes, checksum: 1425117a8c06f2ba303a23663ae033c4 (MD5) Previous issue date: 2002 / Resumo: Neste trabalho estudou-se o transporte de CO2 através da interface água-ar e a sua difusão na água, a partir de experimentos simples e de baixo custo, em escala laboratorial. Para este estudo foram utilizadas soluções aquosas de diferentes salinidades (0, 10, 30 e 65 g/kg), a diferentes temperaturas (25 e 40 °C). Para a determinação da concentração de CO2 dissolvido, adicionou-se indicadores ácido-base. Foram obtidas imagens das soluções a diferentes tempos após o início da difusão. As imagens foram digitalizadas e tratadas com rotinas desenvolvidas utilizando-se o software Matlab. Técnicas de calibração multivariada foram usadas para construir a escala de pH x cor, a partir de curvas de calibração construídas para cada condição experimental. Construiu-se também subrotinas para o cálculo de variogramas e a partir desses calculou-se a dimensão fractal de algumas imagens. Em ensaios iniciais, provou-se que os resultados de velocidade de difusão estão de acordo com a literatura. Nos ensaios definitivos observou-se que os padrões da difusão do CO2 foram reprodutíveis. Ensaios realizados numa cuba retangular em ausência de turbulência mostraram dois padrões de difusão do CO2. Em todas as salinidades, a 40°C e a 25°C com salinidade 65g/kg, o padrão de difusão mostrou uma frente que se desloca de uma maneira regular, na forma de uma cortina. Nas outras condições, a difusão se processa na forma de viscous fingers, caótica e irregular. A salinidade de 65 g/kg proporcionou uma diminuição significativa na velocidade de difusão para ambas as temperaturas. Os resultados foram interpretados em termos da quantidade de CO2 dissolvido, que é maior no segundo caso, e em termos da viscosidade das soluções, que é menor a menor salinidade. Em outro capítulo, estudou-se o fluxo de CO2 e outros gases causadores de efeito estufa (CH4 e N2O) em amostras de pântanos, variando-se a temperatura e a concentração atmosférica de CO2. Os experimentos de medida do fluxo destes gases apresentaram como resultados mais importantes a extrema variabilidade dos valores de fluxo de CH4 e o fato de só se obter uma relação estatisticamente significante entre a produção de CO2 a concentração desse gás na atmosfera / Abstract: In this work CO2 transport through the interface water-air and its diffusion in water, using simple and low cost experiments, in laboratorial scale was studied. Aqueous solutions of different salinities (0, 10, 30 and 65 g/kg) and temperatures (25 and 40° C) had been studied. In order to determinate dissolved CO2 acid-base indicator was added to the solution. Diffusion images were recorded by VHS camera. The images had been digitalized and treated with routines developed using Matlab software. Techniques of multivaried calibration were used to elaborate the pH x color scale from constructed curves of calibration for each experimental condition. It was also constructed subrotines for the calculation of variograms and from them it was calculated the fractal dimension of some images. CO2 diffusion rates obtained in initial assays are in accordance with literature values. In the definitive assays it was observed that the diffusion pattern of CO2 had been reproducible. Assays carried out using a rectangular vessel without turbulence showed two pattern of CO2 diffusion. To all studied salinities, at 40°C and at 25°C with salinity 65 g/kg, the diffusion pattern showed a front that dislocates in a regular way, like a curtain. In the other conditions, the diffusion was chaotic and irregular presenting structures like viscous fingers. The salinity of 65 g/kg provided a significant reduction in the speed of diffusion for both temperatures. The results had been interpreted in terms of the amount of dissolved CO2, that is higher for the second pattern of diffusion and in terms of solutions viscosity, which is proportional to salinity. In another chapter, it was studied the CO2 flow and other greenhouse gases (CH4 and N2O) in wetlands samples, varying its temperature and the atmospheric CO2 concentration. The most relevant results in these measure of the gases flow are the extreme variability of values of CH4 flow. The unique achieved statistically significant obtained relationship was between CO2 production and the concentration of this gas in the atmosphere / Doutorado / Físico-Química / Doutor em Ciências
896

Taxonomia e filogenia molecular de Myxozoa parasitas de peixes de água doce oriundos de ambiente natural e de sistema de criação / Taxonomy and molecular phylogeny of Myxozoa parasites of freshwater fish from natural environment and fish farm

Mateus Maldonado Carriero 12 May 2011 (has links)
O filo Myxozoa possui uma grande diversidade, sendo conhecidas cerca de 2300 espécies, as quais infectam principalmente peixes, mas também anfíbios répteis e aves. Para este estudo, coletas dos peixes de água doce foram realizadas no Pantanal Mato-grossense (estados de Mato Grosso e do Matogrosso do sul) e no Rio Mogi Guaçu e piscicultura do CEPTA/ICMBio (estado de São Paulo), visando estudos moleculares e morfológicos de mixosporídeos parasitas de 6 espécies de peixes. Os resultados das análises moleculares (amplificação e sequenciamento do gene 18S rDNA) e morfológicas revelaram a ocorrência de 11 espécies de mixosporídeos, sendo cinco parasitas comuns a Pseudoplatystoma corruscans e Pseudplatystoma fasciatum, três parasitas de Salminus brasiliensis, uma espécie parasita de Brycon hilarii, uma de Zungaru jahu e outra de Piaractus mesopotamicus. Das onze espécies, cinco ainda não são descritas pela literatura. A análise filogenética, utilizando o método de Neighbor-Joining, mostrou que o agrupamento das espécies ocorre principalmente de acordo com a proximidade filogenética de seus hospedeiros e que todas as espécies da América do Sul agruparam em um clado monofilético. Foi observado, em alguns pontos da árvore filogenética, que o tropismo de tecido e/ou órgão de infecção caracteriza um importante fator de seleção evolutiva. Com menor frequência também foi observado alguns agrupamentos resultantes de parasitas cuja maior relação aparente era a sua localização geográfica, porém, novos estudos ainda são necessários para determinar o verdadeiro papel deste fator na evolução dos mixosporídeos. / The phylum Myxozoa has a great diversity, with about 2300 known species, which infect mainly fishes, but also amphibians, reptiles and birds. In this study, freshwater fishes were caught in the Brazilian Pantanal wetland (Mato Grosso and Mato Grosso do Sul states) and in the Mogi Guaçu River and CEPTA/ICMBio\'s fishfarm (São Paulo state) aiming the molecular and morphological studies of myxosporeans parasites of 6 fish species. The results of molecular (amplification and sequencing of the 18S rDNA gene) and morphological analysis revealed the occurrence of 11 species of myxosporeans, five of them infecting both Pseudoplatystoma corruscans and Pseudoplatystoma fasciatum, three parasites of Salminus brasiliensis, one specie infecting Brycon hilarii, one infecting Zungaro jahu and another infecting Piaractus mesopotamicus. Of these eleven species, five are not yet described by literature. The phylogenetic analysis, using the Neighbor-joining method, showed that the species clustered mainly according to the phylogenetic distance of their hosts and that all species of South America were grouped in a monophyletic clade. In some positions of the phylogenetic tree was observed that tissue tropism and/or organ of infection characterized an important factor in evolutionary selection. Less frequently was also observed some groups containing species which the major apparent relation is its geographical position, however, new studies are still needed to determine the true role of this factor in the evolution of myxosporeans.
897

An analysis of the views of journalists and government officials regarding the impact of new vision's coverage of the Nakivubo Channel Rehabilitation Project

Kaheru, Hamis January 2005 (has links)
No description available.
898

Devenir du phosphore dans les filtres plantés de roseaux : Etude de sa rétention / libération et des facteurs d'influence / Phosphorus dynamics in vertical flow constructed wetlands : Study of its retention / release and influencing factors

Kim, Boram 10 July 2014 (has links)
La gestion « durable » des ressources en phosphore est aujourd’hui un enjeu important du fait de l’épuisement des réserves naturelles et des besoins croissants de l’agriculture notamment. En parallèle, la protection des écosystèmes conduit à des réglementations de plus en plus strictes des rejets de phosphore. L’objectif scientifique de cette thèse est de contribuer à décrire les mécanismes de rétention et de libération du phosphore dans le cadre du traitement des eaux usées domestiques par filtres plantés de roseaux à écoulement vertical, notamment de mieux comprendre où et sous quelle forme le phosphore est retenu dans le système. Plus particulièrement, les travaux ont porté sur le procédé Azoé NP® proposé par la société française SCIRPE, lequel comprend un prétraitement biologique sur lit bactérien, une précipitation du phosphore par injection de chlorure ferrique, puis deux étages de filtres plantés de roseaux à écoulement vertical partiellement immergés. Dans une première phase, nous avons étudié la plus ancienne station de type Azoé NP® située à Vercia (Jura) qui a été suivie depuis 8 ans. Les résultats ont montré les bonnes performances du procédé et leur maintien sur le long terme malgré la forte augmentation de charge organique en automne provenant d’effluents viticoles. Il a été montré que le phosphore était principalement retenu au sein du premier filtre, essentiellement dans la couche de boues organiques qui se forme en surface du 1er étage. L’utilisation de techniques analytiques complémentaires a permis de montrer notamment que leur minéralisation progressive entrainait une évolution des espèces de phosphore au cours du temps, avec par exemple formation de phosphore apatitique. La rétention du phosphore dans les boues a ensuite été étudiée à l’échelle du laboratoire à l’aide de lixiviations successives dans des conditions extrêmes de pH ou d’oxydo-réduction. Les résultats ont montré une très bonne stabilité en conditions de fonctionnement normales. Des essais pilotes ont enfin été réalisés pour approfondir l’évaluation de l’influence du potentiel redox en faisant varier la hauteur d’immersion du milieu filtrant qui influence les conditions d’oxydoréduction. Ces études ont confirmé la stabilité des procédés Azoé NP® et Azoé P® (correspondant au procédé Azoé NP® sans zone d’immersion) en fonctionnement normal. En conditions d’immersion totale prolongée simulant un dysfonctionnement du système, les performances sont dégradées en une semaine, mais le retour en mode totalement insaturé permet un rétablissement très rapide indiquant la bonne résilience du système. / Nowadays, sustainable management of phosphorus resources is an important issue due to the depletion of natural reserves and growing of its agriculture need. In parallel, the protection of ecosystems leads to stringent regulations concerning treatment of phosphorus in wastewaters. The scientific objective of this thesis was to contribute to describing the phosphorus retention and release in domestic wastewater treatments by vertical flow constructed wetlands, especially to better understand where and in which form the phosphorus is retained in the system. In particular, the work focused on the process Azoé NP® proposed by the French company SCIRPE, which includes a biological pretreatment on trickling filter, precipitation of phosphorus by injection of ferric chloride and two stages of partially flooded vertical flow constructed wetland. First of all, we studied the oldest Azoé NP® type station located at Vercia (Jura, France) which was monitored for 8 years. The results showed that the Vercia treatment plant provided robust year-round treatment of municipal wastewater and winery wastewater during automn. It was found that the phosphorus was principally retained within the deposit organic sludge layer on the surface of the first stage of filteration. The use of additional analytical techniques showed that phosphates species within this deposit layer changed during the mineralization of organic matters over time. The formation of amorphous apatite species was also discussed. The stability of the retention of phosphorus in sludge was then studied at laboratory scale using successive leaching under extreme conditions of pH or redox potential. The results showed a very good stability of sludge from the Vercia plant in normal operating conditions. Pilot tests were finally performed to evaluate the influence water saturation level within the filter medium which affect redox conditions of the system. These studies confirmed the stability of processes Azoé NP® and Azoé P® (corresponding to the process Azoé NP® without water saturation within filter media) during normal operation. Under conditions of prolonged immersion simulating a malfunctionning of the system, the performance was degraded after one week of flooding. However, the return to fully unsaturated mode allowed a very fast recovery of the filter, showing a good resilience of the system.
899

Modelování biochemických pochodů ve filtračním prostředí kořenových čistíren / Modelling of the biochemical processes in the constructed treatment wetlands

Pumprlová Němcová, Miroslava January 2015 (has links)
This master's thesis deals with the modeling of biochemical processes in saturated vertical filter (which is often part of constructed treatment wetland) using software HYDRUS 2D and the module Constructed Wetland CW2D. The introductory part of this thesis is the literature research of expertise that are introduce with the theme constructed treatment wetlands and should also provide a basic overview of the mathematical or numerical modeling issue. The last chapter describes the theoretical introduction of software HYDRUS 2D and CW2D module, it is the practical part used to create a numerical l model. The practical part is based on theoretical knowledge and demonstrates the creating process of mathematical model in program HYDRUS 2D, simulating the real biochemical processes on the vertical saturated filter. The model is created in the program HYDRUS 2D CW2D and based on real operated constructed wetland. The thesis describes the calibration and followed verification of this model. The final model can well simulate the real filter behavior and allows user to get information about the output concentrations of waste water emission, such as ammonia nitrogen (N-NH4+) and chemical oxygen demand (COD). The results should in the future contribute to create software intended to draft and layout constructed wetlands.
900

Identification of processes leading to long-term wastewater purification in northern treatment wetlands

Karjalainen, S. M. (Satu Maaria) 16 August 2016 (has links)
Abstract Treatment wetlands (TW) constructed on natural wetlands potentially perform efficient purification of wastewater, but the longevity of TWs at northern latitudes is not well known. This thesis examined processes affecting nutrient and suspended solids (SS) retention in TWs during their lifetime. In total, 15 TWs were studied using water and peat quality and gas flux data for different TW life lengths, the longest period being 18 years. The TWs commonly retained nutrients and suspended solids efficiently, even after 18 years of wastewater loading. For nitrogen (N) removal, sedimentation, nitrification-denitrification and plant uptake were efficient processes in the wetlands studied. However, emissions of nitrous oxide (N2O) from TWs are not a major contributor to climate change due to the small total surface area of TWs. The significance of anaerobic ammonium oxidation (anammox) and other newly discovered nitrogen processes in TWs remains to be clarified. Phosphorus (P) adsorption capacity in TWs remained efficient over a 12-year study period, the process being continuous when surfaces for adsorption were available or freed up through alternating absorption/desorption/adsorption. Phosphorus accumulation by peat accretion was low, but has not been well assessed in northern TWs receiving nutrient-rich waters. Iron (Fe) and aluminium (Al) in peat extraction runoff and purified wastewater from sewage treatment plants were of great importance for precipitation of P in TWs. Filtration and sedimentation of organic humic substances with Fe- or Al-bound P were other probable P retention pathways. In peat extraction runoff, Fe was more significant than Al for P retention, but Fe-bound P is susceptible to desorption in anaerobic environments, whereas Al-bound P is more strongly retained. Suspended solids were generally retained well, although there was great variation in percentage retention in individual TWs in different years and different seasons. Changes in discharge affected SS transportation and retention. SS were retained by sedimentation, the rate of which was affected by particle size. It is plausible that smaller particles from old peat extraction areas where the extracted peat has a high humification degree erode more easily than poorly humified particles in surface peat. Weakened SS retention may also have been caused by development of preferential flow areas (PFA) in TWs, changes in sediment delivery characteristics and sampling involving too few samples to show SS transportation sufficiently accurately for estimating SS retention. Thus TWs are potentially ideal for purification of wastewater and can have high purification efficiency even after long-term use in northern regions. They are also more widely applicable as long as their limitations are understood. / Tiivistelmä Kosteikkopuhdistamot, jotka on rakennettu luonnonkosteikoille, voivat tehokkaasti vähentää erilaisten maankäyttömuotojen ja pistekuormituslähteiden vesistökuormitusta. Niiden käyttöikää pohjoisilla alueilla ei kuitenkaan tunneta hyvin. Tässä väitöskirjassa tarkastellaan kosteikkopuhdistamoissa tapahtuvia biologisia, kemiallisia ja fysikaalisia prosesseja, joilla on vaikutusta ravinteiden ja kiintoaineen pidättymiseen. Yhteensä 15 eri-ikäisen kosteikkopuhdistamon toimintaa tutkittiin veden ja turpeen laadun sekä kasvihuonekaasumittausten avulla. Näistä vanhinta kosteikkoa oli tutkimusta tehdessä käytetty 18 vuotta turvetuotannon valumavesien puhdistukseen. Tyypillisesti kosteikkopuhdistamot pidättivät ravinteita ja kiintoaineita tehokkaasti jopa 18 vuoden käytön jälkeen. Typenpoistossa sedimentaatio, nitrifikaatio-denitrifikaatio ja kasvien ravinteidenotto olivat tutkituilla kosteikoilla tehokkaita prosesseja. Kosteikkopuhdistamoiden typpioksiduulipäästöt (N2O) ilmaan eivät kuitenkaan ole merkittäviä ilmastonmuutoksen aiheuttajia, koska tällaisten kosteikkopuhdistamoiden kokonaispinta-ala on pieni. Anammox- (anaerobic ammonium oxidation) ja muiden viimeaikoina muissa tutkimuksissa havaittujen typpiprosessien merkitys kosteikoilla tulisi vielä selvittää. Fosforin adsorptiokyky kosteikkopuhdistamoilla pysyi tehokkaana 12 vuoden tutkimusjaksolla, koska niissä adsorptiopintoja oli joko vapaana tai niitä vapautui absorptio- ja desorptioprosessien seurauksena. Kosteikkopuhdistamolla fosforin kertyminen turpeen muodostuksessa arvioitiin vähäiseksi, tosin kertymistä ei ole tarkkaan määritetty pohjoisilla kosteikkopuhdistamoilla, joihin tulee ravinteikasta vettä. Turvetuotannon valumavesissä ja jätevedenpuhdistamoilta tulleissa vesissä orgaanisten humusaineiden rautaan ja alumiiniin sitoutuneen fosforin suodattuminen ja sedimentoituminen olivat muita todennäköisiä fosforin pidättymismekanismeja kosteikoilla. Turvetuotannon valumavesissä rauta oli alumiinia merkittävämpi tekijä fosforin pidättymisessä. Rautaan sitoutunut fosfori on kuitenkin altis desorptiolle hapettomissa olosuhteissa, kun taas alumiiniin sitoutunut fosfori pidättyy pysyvämmin. Kiintoaines pidättyi kosteikkopuhdistamoissa yleensä hyvin, vaikka pidättyneen aineen osuudessa kokonaiskuormituksesta oli suurta vaihtelua yksittäisissä kosteikkopuhdistamoissa eri vuosina ja eri vuodenaikoina. Muutokset virtaamissa vaikuttivat kiintoaineksen kulkeutumiseen ja pidättymiseen. Kiintoaines pidättyy sedimentaatiossa, jonka suuruuteen vaikuttaa kiintoaineen partikkelikoko. On todennäköistä, että vanhojen turvetuotantoalueiden korkean humusasteen pienikokoiset turvepartikkelit erodoituvat helpommin kuin pintaturpeen vähemmän hajonneet partikkelit. Heikentynyt kiintoaineen pidättyminen saattaa aiheutua myös kosteikkopuhdistamoiden oikovirtauksien kehittymisestä, muutoksista sedimentin kulkeutumistavoissa ja liian harvoista näytteenotoista, jolloin ei pystytä riittävän tarkasti arvioimaan kiintoaineksen pidättymistä. Kosteikkopuhdistamot voivat olla ideaalisia jätevesien puhdistamiseen ja ovat osoittaneet hyvää puhdistustehokkuutta myös pitkäaikaisessa käytössä pohjoisissa olosuhteissa. Siten ne ovat laajasti sovellettavissa, kunhan niiden käyttömahdollisuuksien rajoitteet on otettu huomioon.

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