In der vorliegenden Arbeit werden für ein stark anthropogen beeinflusstes Einzugsgebiet die komplexen Zusammenhänge zwischen Witterung, Landnutzung, Erosion, Gerinneabfluss, Stofffrachten und Makrozoobenthos analysiert. Dafür wurde eine Messstation eingerichtet, an der Fließgeschwindigkeit, Trübung, pH Wert und Leitfähigkeit kontinuierlich gemessen wurden. Mit Hilfe eines durchflussgesteuerten Probennehmers wurden Wasserproben entnommen und im Labor auf verschiedene Inhaltsstoffe (Nährstoffe, Schwermetalle) analysiert sowie die Konzentration von Feinsediment bestimmt. Es konnte eine Beziehung zwischen Trübung und Sedimentkonzentration abgeleitet werden. Die chemischen Analysen zeigten einen komplexen Zusammenhang zwischen der Erosion von landwirtschaftlichen Flächen, dem Stoffeintrag von versiegelten Arealen (Verkehrsflächen, Dächer) aber auch witterungs- und vegetationsbedingte saisonale Effekte. Ein Vergleich der Eigenschaften der Schwebstoffe/Feinsediment im Landwasser mit denen von Ackerboden (Maisfelder) zeigte, dass diese die „chemische Handschrift“ der Ackerböden trugen. Mit Hilfe der Modelle EROSION 3D und ICECREAM wurden die abgetragenen Bodenmengen für das Einzugsgebiet bzw. für ausgewählte Hänge quantifiziert. EROSION 3D überschätzt den Bodenaustrag aus dem Untersuchungsgebiet deutlich. Das Modell ist ungeeignet, um für das Einzugsgebiet reale Abtragswerte mit den zur Verfügung stehenden flächenhaften Eingangsdaten zu berechnen. Bereits für Einzelhänge werden zu große Bodenabträge berechnet. Verstärkend kommt hinzu, dass auf Grund der Modellannahme jeder Partikel, der das Gewässer erreicht auch aus dem Einzugsgebiet heraustransportiert wird. Das Modell kann empfohlen werden, um erosionsgefährdete Flächen auszuweisen. In der Untersuchungsperiode von 2009 bis Juli 2011 wurde an Hand von 57 Driftfängen mit unterschiedlichen hydrologischen Randbedingungen die Wirkung der Fließgeschwindigkeit auf den Übergang benthischer Invertebraten in die freie Welle identifiziert. Aus Uferbereichen gelangen zufällig terrestrische Invertebraten in das Gewässer, deren Anteil sich durch gewässernahen Oberflächenabfluss in Folge von Niederschlagsereignissen erhöht. Die Driftdichte nimmt ab Fließgeschwindigkeiten von 0,3 m/s deutlich zu. Oligochaeta, Cyclopoida und Dipolstraca driften verstärkt bei Fließgeschwindigkeiten >0,6 m/s.

The objectives of this study are to investigate the biodiversity in different unit of treatment systems, and to detect the function in a salt water type of constructed wetland. We investigated the benthic invertebrate community in different stage from 2010 July to 2011 May, while the parameters of TKN, NH3-N, organic nitrogen, TP, TOC and particle size were measured in the sediments of each sampling site at the same time in the wetland system. The results show that concentrations of organic matter and nutrients in the sediments were increased with time monthly. In May of 2010, the concentration of NH3-N were found the highest one(ANOVA, p<0.05). The particle size in sampling site 1 were the highest (ANOVA, p<0.05), while in November of 2010 all sampling sites were found exhibiting significantly different with other months (ANOVA, p<0.05). Further more, for the diversity of benthic invertebrate, we found that the parameter of the temperature was strongly negatively related to the species diversity, species abundance and species evenness, respectively (r=-387[H¡¦]¡F-533[d]¡F-438[J¡¦] ). The species diversity was increased with organic nitrogen concentrations in the sediments (r=0.492[TKN]¡F0.408[NH3-N]¡F0.493[org-N]), and were negatively related to the parameters of DO and particle size(r=-0.402[Particle size]¡F-0.287[DO] ). In addition, PCA shows that the parameters of particle size¡Borg-N¡BNH3-N¡BTKN and TOC were all important factors. Generally, it was concluded that the constructed systems, which is functioned of wetland was wastewater treatment mainly, exhibit no significant function in biodiversity.

Communities in the vicinity of the Mico River, located in Chontales, Nicaragua, suffer from periodic dry season water shortages. The Mico River is impacted by artisanal and industrial mining, cattle ranching, effluent from local dairies and tanneries, and poor waste management practices in the watershed. Available water quality data consists of short term assessment studies and monitoring data for a mine operating in the headwaters, but to date this information has not been collated and interpreted as a whole. Communities in the vicinity of the Mico River have expressed an interest in having this data reviewed to verify information they have received from government and industry with regards to impacts from the La Libertad Mine. A gap analysis of existing water quality data in the headwaters of the Mico River is presented, with interpretation of current data and identification of further data needs. Recommendations are provided for future water quality monitoring in the region. The study area was defined as the Mico River watershed upstream of the town of Santo Tomas. A total of 14 studies were identified with information about the Mico River in this area. Individual study reliability was assessed, and study data were compiled to assess conditions in comparison to water quality guidelines and any spatial or temporal trends. Both water chemistry and bioassessment studies were assessed. The major gaps in existing information are: insufficient baseline/ reference information, insufficient information on impacts from contaminants other than metals, insufficient coverage of streams not directly impacted by the La Libertad Mine, poor quality and reliability of data, and poor coordination/ continuity between studies done to date. Cyanide concentrations were found to be below drinking water criteria at the majority of sample locations. Metals concentrations were elevated throughout the study area but it cannot be determined if this is due to natural background levels or anthropogenic sources. Water quality conditions with regards to other parameters (e.g., dissolved oxygen, temperature, pesticides and bacteria) and bioassessment data cannot be assessed due insufficient data quality and quantity. Existing monitoring in the region should be expanded to include reference locations. It is recommended that a benthic invertebrate bioassessment program designed for tropical mountain streams be implemented to supplement existing monitoring and identify areas where stream function is impaired, as bioassessment is cheaper and requires less equipment and logistical coordination than water chemistry monitoring programs. Whatever future work is done, care must be taken that study design and implementation is of a higher quality than that done to date, so that results are comparable and reliable. Coordination and cooperation between bodies involved in monitoring is essential for efficient use of scarce resources. / Graduate

L'écosystème aquatique est le résultat d'un équilibre entre l'environnement naturel et les organismes qui s'y développent. Cet équilibre peut être modifié par l'introduction de substances chimiques dues aux activités humaines. Aujourd'hui, l'impact de cette micropollution est encore mal connu, particulièrement pour les organismes constituant les premiers maillons des chaînes trophiques qui requièrent des efforts analytiques importants en raison de leur faible taille. L'objectif de ces travaux est centré sur le développement, la validation et l'application d'outils analytiques permettant d'étudier la bioaccumulation et la biotransformation de polluants émergents chez des invertébrés benthiques. Cette étude s'est focalisée sur 3 organismes aquatiques d'eau douce : C. riparius, G. fossarum et P. antipodarum. Une méthode analytique pour la quantification de 35 polluants émergents chez les 3 espèces sélectionnées a ainsi été développée. Elle permet d'accéder aux premières données de bioaccumulation des substances d'intérêts à l'échelle d'un individu grâce à la mise en oeuvre d'une stratégie analytique entièrement miniaturisée, incluant une extraction MicroQuEChERS suivie d'une analyse par nanochromatographie liquide couplée à la spectrométrie de masse en tandem. Afin de mieux comprendre l'impact d'une telle pollution sur les espèces sélectionnées et d'obtenir une vue globale des capacités de biotransformation de celles-ci, une approche métabolomique a été mise en place. Enfin, un nouveau mode de quantification par MRM3 a été utilisé pour dépasser la complexité de telles matrices, et fournir une évaluation fiable des cinétiques de bioaccumulation de potentiels traceurs de pollution anthropique / The aquatic ecosystem is the result of a balance between the natural environment and the organisms that inhabit it. This balance can be modified by the input of excessive amount of substances generated from human activities. Nowadays, the impact of this pollution is still little known, especially regarding the risk of bioaccumulation in the first trophic levels. This lack of data could be partially explained by the lack of suitable analytical method for small organisms. In this context, the aim of this study is to establish the development, the validation and the application of analytical tools for the assessment of bioaccumulation and biotransformation of emerging pollutants in freshwater invertebrates. Three benthic invertebrates are chosen for this project: C. riparius, G. fossarum and P. antipodarum. Analytical method has been developed for the quantification of 35 emerging pollutants in the selected species. This method provides the first bioaccumulation data of targeted substances in individual scale through the implementation of miniaturized analytical strategy, including an extraction step based on MicroQuEChERS followed by nanoliquid chromatography coupled to tandem mass spectrometry analysis. To better understand the impact of such pollution and to obtain a global view of the biotransformation capacities of the selected organisms, metabolomics approach has been put in place. Finally, a new quantification mode based on MRM3 was used to overcome biotic matrix complexity and assess the bioaccumulation kinetics of potential tracers of anthropic pollution

In der vorliegenden Arbeit werden für ein stark anthropogen beeinflusstes Einzugsgebiet die komplexen Zusammenhänge zwischen Witterung, Landnutzung, Erosion, Gerinneabfluss, Stofffrachten und Makrozoobenthos analysiert. Dafür wurde eine Messstation eingerichtet, an der Fließgeschwindigkeit, Trübung, pH Wert und Leitfähigkeit kontinuierlich gemessen wurden. Mit Hilfe eines durchflussgesteuerten Probennehmers wurden Wasserproben entnommen und im Labor auf verschiedene Inhaltsstoffe (Nährstoffe, Schwermetalle) analysiert sowie die Konzentration von Feinsediment bestimmt. Es konnte eine Beziehung zwischen Trübung und Sedimentkonzentration abgeleitet werden. Die chemischen Analysen zeigten einen komplexen Zusammenhang zwischen der Erosion von landwirtschaftlichen Flächen, dem Stoffeintrag von versiegelten Arealen (Verkehrsflächen, Dächer) aber auch witterungs- und vegetationsbedingte saisonale Effekte. Ein Vergleich der Eigenschaften der Schwebstoffe/Feinsediment im Landwasser mit denen von Ackerboden (Maisfelder) zeigte, dass diese die „chemische Handschrift“ der Ackerböden trugen. Mit Hilfe der Modelle EROSION 3D und ICECREAM wurden die abgetragenen Bodenmengen für das Einzugsgebiet bzw. für ausgewählte Hänge quantifiziert. EROSION 3D überschätzt den Bodenaustrag aus dem Untersuchungsgebiet deutlich. Das Modell ist ungeeignet, um für das Einzugsgebiet reale Abtragswerte mit den zur Verfügung stehenden flächenhaften Eingangsdaten zu berechnen. Bereits für Einzelhänge werden zu große Bodenabträge berechnet. Verstärkend kommt hinzu, dass auf Grund der Modellannahme jeder Partikel, der das Gewässer erreicht auch aus dem Einzugsgebiet heraustransportiert wird. Das Modell kann empfohlen werden, um erosionsgefährdete Flächen auszuweisen. In der Untersuchungsperiode von 2009 bis Juli 2011 wurde an Hand von 57 Driftfängen mit unterschiedlichen hydrologischen Randbedingungen die Wirkung der Fließgeschwindigkeit auf den Übergang benthischer Invertebraten in die freie Welle identifiziert. Aus Uferbereichen gelangen zufällig terrestrische Invertebraten in das Gewässer, deren Anteil sich durch gewässernahen Oberflächenabfluss in Folge von Niederschlagsereignissen erhöht. Die Driftdichte nimmt ab Fließgeschwindigkeiten von 0,3 m/s deutlich zu. Oligochaeta, Cyclopoida und Dipolstraca driften verstärkt bei Fließgeschwindigkeiten >0,6 m/s.

Sediment quality guidelines (SQGs) or values (SQVs) are used to assess the potential risk of contaminants in sediment to aquatic organisms, specifically benthic invertebrates. The objectives of this research were to evaluate SQGs derived specifically for use by the uranium industry in Canada, propose alternative SQVs for use at uranium operations in northern Saskatchewan using a novel approach, and investigate the potentially bioavailable fractions of metals in sediment which could become an alternative measurement to the typically used total metal concentrations. The screening-level concentration (SLC) approach has been used in Ontario, Canada, to derive lowest effect levels (LELs) and severe effect levels for use as SQGs. This approach was adopted by the Canadian Nuclear Safety Commission (CNSC) to set guidelines for metals (As, Cr, Cu, Pb, Mo, Ni, Se, U, and V) and radionuclides (Ra-226, Pb-210, and Po-210) in sediment at northern Saskatchewan uranium mining and milling operations. The SLC approach is based on total metal and radionuclide concentrations in sediment, and corresponding benthic invertebrate community composition data for a specific sampling site. In this study, sediment chemistry (total metals and radionuclides) and benthic community data from northern Saskatchewan uranium operations were compiled and examined. Results indicated that the CNSC-derived SQGs had limited relationships to observed effects, or lack thereof, on benthic invertebrate communities near uranium operations in Saskatchewan. On a general basis, the correct alignment of at least one LEL exceedence at an effect site was observed 95% of the time, but on an element-specific basis many of the elements had concentrations at effect sites below their LELs. Furthermore, concentrations of the evaluated elements exceeded at least one LEL at 60% of the no-effect sites. The high number of exceedences of LELs at reference and no-effect sites (false-positives) calls to question the appropriateness of the CNSC-derived SQGs. To address the deficiencies of the SLC approach, a new approach was developed to derive alternative metal SQVs for the uranium industry in northern Saskatchewan that was based on the use of reference and no-effect site field data. Three different sets of NE values were derived using combinations of benthic invertebrate community effect criteria (abundance, richness, evenness, Bray-Curtis index). Additionally, reference (REF) values were derived based solely on sediment metal concentrations from reference sites. In general, NE values derived using abundance, richness, and evenness (NE1 and NE2 values) were found to be higher than the NE values derived using all four metrics (NE3 values). Derived NE values for Cr, Cu, Pb, and V did not change with the incorporation of additional effects criteria due to a lack of influence from the uranium operations on these metal concentrations (i.e., they were generally present at or near background levels). However, a gradient of exposure concentrations was apparent for As, Mo, Ni, Se, and U in sediment which allowed for acceptable exposure levels of these metals in sediment to be defined. The findings from this assessment proposed a set of new, alternate SQVs for use at the uranium industry in northern Saskatchewan. Often, only total metals concentrations are measured in the evaluation of contaminated sediment. However, this measure may over-estimate metal exposure to benthic invertebrates. Using sediment cores collected from near the Rabbit Lake and Key Lake uranium operations, along with a series of mixed-sediments (contaminated and reference sediment), metal bioaccumulation experiments using Chironomus dilutus were conducted in the laboratory. Metal concentrations in extracts from single extractions with either potassium phosphate or hydrochloric acid on wet and dried sediment, pore-water, and whole-sediment were used to evaluate metal bioaccumulation in test organisms. Depending on the metal, pore-water isolated using peepers generally exhibited the best relationship with tissue metal concentrations. Based on this finding, it is suggested that pore-water sampling using peepers (an in-situ dialysis device) be added to environmental sampling programs at Saskatchewan uranium operations so that sediment metal availability to benthic invertebrates can be better assessed. With the eventual development of a larger pore-water metals dataset, SQGs based on pore-water metals concentrations could likely be derived as an alternative to existing SQGs based on total metal concentrations in sediment.

Sediment quality guidelines (SQGs) or values (SQVs) are used to assess the potential risk of contaminants in sediment to aquatic organisms, specifically benthic invertebrates. The objectives of this research were to evaluate SQGs derived specifically for use by the uranium industry in Canada, propose alternative SQVs for use at uranium operations in northern Saskatchewan using a novel approach, and investigate the potentially bioavailable fractions of metals in sediment which could become an alternative measurement to the typically used total metal concentrations. The screening-level concentration (SLC) approach has been used in Ontario, Canada, to derive lowest effect levels (LELs) and severe effect levels for use as SQGs. This approach was adopted by the Canadian Nuclear Safety Commission (CNSC) to set guidelines for metals (As, Cr, Cu, Pb, Mo, Ni, Se, U, and V) and radionuclides (Ra-226, Pb-210, and Po-210) in sediment at northern Saskatchewan uranium mining and milling operations. The SLC approach is based on total metal and radionuclide concentrations in sediment, and corresponding benthic invertebrate community composition data for a specific sampling site. In this study, sediment chemistry (total metals and radionuclides) and benthic community data from northern Saskatchewan uranium operations were compiled and examined. Results indicated that the CNSC-derived SQGs had limited relationships to observed effects, or lack thereof, on benthic invertebrate communities near uranium operations in Saskatchewan. On a general basis, the correct alignment of at least one LEL exceedence at an effect site was observed 95% of the time, but on an element-specific basis many of the elements had concentrations at effect sites below their LELs. Furthermore, concentrations of the evaluated elements exceeded at least one LEL at 60% of the no-effect sites. The high number of exceedences of LELs at reference and no-effect sites (false-positives) calls to question the appropriateness of the CNSC-derived SQGs. To address the deficiencies of the SLC approach, a new approach was developed to derive alternative metal SQVs for the uranium industry in northern Saskatchewan that was based on the use of reference and no-effect site field data. Three different sets of NE values were derived using combinations of benthic invertebrate community effect criteria (abundance, richness, evenness, Bray-Curtis index). Additionally, reference (REF) values were derived based solely on sediment metal concentrations from reference sites. In general, NE values derived using abundance, richness, and evenness (NE1 and NE2 values) were found to be higher than the NE values derived using all four metrics (NE3 values). Derived NE values for Cr, Cu, Pb, and V did not change with the incorporation of additional effects criteria due to a lack of influence from the uranium operations on these metal concentrations (i.e., they were generally present at or near background levels). However, a gradient of exposure concentrations was apparent for As, Mo, Ni, Se, and U in sediment which allowed for acceptable exposure levels of these metals in sediment to be defined. The findings from this assessment proposed a set of new, alternate SQVs for use at the uranium industry in northern Saskatchewan. Often, only total metals concentrations are measured in the evaluation of contaminated sediment. However, this measure may over-estimate metal exposure to benthic invertebrates. Using sediment cores collected from near the Rabbit Lake and Key Lake uranium operations, along with a series of mixed-sediments (contaminated and reference sediment), metal bioaccumulation experiments using Chironomus dilutus were conducted in the laboratory. Metal concentrations in extracts from single extractions with either potassium phosphate or hydrochloric acid on wet and dried sediment, pore-water, and whole-sediment were used to evaluate metal bioaccumulation in test organisms. Depending on the metal, pore-water isolated using peepers generally exhibited the best relationship with tissue metal concentrations. Based on this finding, it is suggested that pore-water sampling using peepers (an in-situ dialysis device) be added to environmental sampling programs at Saskatchewan uranium operations so that sediment metal availability to benthic invertebrates can be better assessed. With the eventual development of a larger pore-water metals dataset, SQGs based on pore-water metals concentrations could likely be derived as an alternative to existing SQGs based on total metal concentrations in sediment.