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GENERAL ABSTRACT The Laurentian Great Lake wetlands are highly productive and complex systems. The net loss of wetlands since European settlement has been dramatic. The remaining coastal wetlands continue to be threatened with obliteration or severe environmental degradation. Therefore, the overall objective of this study was to provide information on the ecology of the remaining coastal wetlands within the lower Great Lakes. This study describes a coastal wetland fish community along the north shore of Lake Erie within Long Point Marsh complex over a 24-h period and catch characteristics of three common fishing techniques. The fish community was sampled at two hour intervals over a 24-h period in June, and used three types of gear to determine possible sampling biases from the different collection techniques. A total of 497 fish encompassing 11 taxa were collected. A 2-h interval, four hours prior to sunset, netted the largest number of taxa (including 3 functional feeding groups: ornmvores, planktivores, and piscivores ), as well as highest abundance and biomass values. Seine netting demonstrated a biased towards sampling the smaller planktivores, while fyke nets were biased towards larger omnivorous fish, and boat electrofishing was biased towards the large piscivores. These results will assist scientists and lake managers to develop standardized fish sampling protocol in order to accurately assess differences in wetland fish communities. Seven coastal wetlands within Lake Erie and Ontario along both the Canadian and United States shorelines were studied to verify predicted relationships from the literature and determine the relative influences of various habitat features on zooplankton community structure. Water quality, aquatic macrophyte, zooplankton, and fish community information were collected from the wetlands between July 4th and August 2nd of 2001. The predicted relationships from the literature concerning water quality and macrophyte species richness were verified by the results of this work. Water quality and macrophyte species richness were the most accurate predictors of wetland zooplankton community structure. Identifying the wetland characteristics that play primary roles in structuring zooplankton communities will also assist lake managers to make informed decisions of how to most effectively improve zooplankton habitat, to foster larger-bodied zooplankton populations, making the habitat more suitable for larger populations of larval and juvenile fish. / Thesis / Master of Science (MS)

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Våta marker utgjorde tillsammans med andra miljöer en variation i det historiska landskapet. När människor behövde den våta marken för odling betraktades den som ogynnsam och marken avvattnades. Endast 10 % av den ursprungliga våtmarksarealen finns idag kvar i Skåne. Våta marker blev begreppet våtmarker när människan förstod dess värden. I uppsatsen studeras våtmarksförändringar och markanvändningsutveckling mellan tidigt 1800-tal och 2017 vid Ivösjön i nordöstra Skåne. Uppsatsen kartlägger också hur dikningsföretag har påverkat våtmarkernas förändring.  Utifrån historiskt kartmaterial och Lantmäteriets höjddata har GIS-analyser utförts och jämförts med relevant litteratur. Våtmarkernas kvarvarande areal är mellan 9 % och 14 % och samstämmer med de generella siffrorna över Skåne, dock finns avvikelser vid ett område (43 %). Markanvändningens utveckling följer de allmänna trenderna. Hur dikningsföretagen påverkat markanvändningen kräver vidare undersökningar.

<p>During the nineties, ecological handling of urban storm water became very popular in Sweden. Together with Chalmers University of Technology and two Swedish communities, DHI Water and Environment has been doing research of storm water ponds and constructed wetlands. This thesis work is a part of that research project. The work has been applied at the Bäckaslöv storm water treatment plant in Växjö, Sweden. The plant consists of one storm water pond and a downstream constructed wetland. Simulations in two different modelling programs, MIKE SHE WET and MIKE 21 have been performed. MIKE SHE WET has never been used in practical work. The purpose of the program is to describe chemical and biological processes in wetlands and how the plants affect the retention of nutrients in the water. Since the program never has been used before, the main work has been to test the model to investigate whether it fulfil its purpose or not. MIKE 21 has been used to describe how the geometry influences the retention of suspended material, nitrogen and phosphorus. MIKE 21 has also been used to study how the wetland works without the storm water pond. To be able to describe the natural processes going on in wetlands the program MIKE SHE WET has to be further developed. The work has yet resulted in a package of measures that can improve the model. Science is in need for a model like MIKE SHE WET. If the program will be edited it can contribute a lot to the research of wetlands and storm water treatment. The simulations in MIKE 21 show that today’s shape of the wetland is not most favourable. If the water was spread over a bigger area the retention of nitrogen, phosphorus and suspended material would increase.</p> / <p>Anläggandet av konstgjorda våtmarker och sedimenteringsdammar har varit intensivt under nittiotalet och ekologisk dagvattenhantering har blivit mycket populärt i Sveriges kommuner. DHI Water and Environment bedriver i samarbete med Chalmers tekniska Högskola samt Växjö och Örebro kommuner ett forskningsprojekt kring anlagda dammar och våtmarker. Meningen är att resultaten ska kunna användas vid såväl uppföljningsarbete av befintliga dammar samt vid anläggandet av nya dagvattenanläggningar. Detta examensarbete ingår som en del av ovan nämnda forskningsprojekt. Arbetet har tillämpats på Bäckaslövs dagvattenanläggning i Växjö. Anläggningen består av en sedimenteringsdamm med efterföljande våtmark. Modellstudier har utförts i två olika modellprogram, MIKE SHE WET och MIKE 21. MIKE SHE WET har inte tidigare använts i praktiken och har därför testats för att undersöka om programmet uppfyller sitt syfte. Programmet har utformats för att kunna simulera växternas påverkan på kväve- och fosforretentionen. Med hjälp av MIKE 21 har simuleringar utförts för att undersöka hur våtmarkens geometri kan förändras för att få en optimerad avskiljning av kväve, fosfor och suspenderat material. Simuleringar har också utförts för att undersöka hur våtmarken skulle fungera utan uppströms liggande sedimenteringsdamm. Resultaten visar på att MIKE SHE WET måste vidareutvecklas för att kunna beskriva de biologiska och kemiska processer som pågår i våtmarken. Arbetet har lett fram till ett antal konkreta åtgärdsförslag för att förbättra programmet och modellen har potential att bli ett viktigt hjälpmedel i framtida forskning kring våtmarker. MIKE 21-simuleringarna har visat mycket goda resultat. Resultaten visar på att våtmarken idag inte har optimal utformning för att kunna rena det dagvatten som flödar in i den. Om våtmarken utformas så att vattnet får en större spridning i området kommer reningen av såväl suspenderat material som kväve och fosfor att förbättras.</p>

Storm water runoff is a leading cause of degradation in the water quality of receiving water bodies. Although legislation requires that Environmental Impact Assessments (EIA) are performed and Environmental Management Plans (EMP) put in place for the construction of high density housing developments, there is generally very little evidence that real measures are developed to monitor and actually assess the extent of the impact that construction activities have on the environment during the physical construction stage. The water quality of stormwater runoff from a mixed use catchment including construction sites in Seaward Estates, Ballito, KwaZulu-Natal that enters a coastal forest wetland system was characterised by monitoring programmes established at three study areas. The effect thereof on the quality of the wetland water and sediments was further monitored at five points along the drainage line of the system. The investigation focussed on obtaining representative stormwater samples in order to quantitatively identify pollutant constituents transported within stormwater runoff from construction sites during rainfall events. Storm water runoff event mean concentration (EMC), atmospheric deposition and wetland water and sediment samples were collected over an eight month period. The characterisation of stormwater runoff for this investigation included heavy metals, oxygen demanding substances, sediments and physico-chemical analysis for pH, conductivity and ammonia and nitrates. The majority of contaminant EMC exceeded the South African wastewater discharge general and special limits. The findings from this investigation will provide planners and decision-makers with a greater understanding of the pollution dynamics of construction sites aiding in improved best management practice decisions with regard to minimizing impacts on coastal forest wetlands and water resources. This will lead to improved EMP and stormwater management plans (SWMP) incorporating stormwater pollution prevention plans (SWPPP) for construction sites. / Thesis (M.Sc.Eng.)-University of KwaZulu-Natal, Durban, 2007.