Thesis (M.S.)--California Polytechnic State University, 2010. / Title from PDF title page; viewed on March 18, 2010. Major professor: Royden Nakamura, Ph.D. "Presented to the faculty of California Polytechnic State University, San Luis Obispo." "In partial fulfillment of the requirements for the degree [of] Master of Science in Biological Sciences." "February 2010." Includes bibliographical references (p. 78-90).

Thesis (Ph. D.)--University of Chicago, Dept. of Ecology and Evolution, August 2003. / Includes bibliographical references. Also available on the Internet.

The self-treatment system of nature cannot handle man-caused high rate water pollution on its own, therefore cleaning in wastewater treatment plant (WWTP) is necessary to avoid eutrophication – excessive enrichment of nature by nutrients. Current technologies applied in WWTPs are old, outdating and highly energy demanding, especially biological treatment step generally requires large amount of energy for aeration of water. The alternative to current system could be microalgae treatment step, which would use green algae to consume pollutants present in the waste water, namely nitrogen, phosphorus and heavy metals. Via photosynthesis it could produce oxygen required for biological oxidation of organic matter. Furthermore carbon source is necessary for microalgal growth, this can be added to the water as CO2 produced in other industries and so decrease global greenhouse gas footprint. Co-digestion of microalgae with undigested wastewater sludge under mesophilic conditions can give a synergic effect for biogas production, therefore harvested and co-digested microalgae could contribute to positive energy balance of WWTP. Full-scale microalgae cultivation in WWTP can be achieved only when good grow is guaranteed. This is a result of many factors, particularly access to nutrients, light condition, water temperature, and pH. The goal of master’s thesis was to understand and evaluate main factors influencing algal growth using literature review, propose design of microalgae treatment step with artificial lights and evaluate energy balance, of wastewater treatment plants in Uppsala and Västerås with new design. The work proposed two different designs of microalgae treatment steps, modelled in Excel and applied to current state of municipal WWTP in Västerås and Uppsala with belonging satellite plants. The first design of microalgae activated photobioreactor (MAASPBR) aimed to replace current biological treatment step. This is possible in Västerås and Uppsala WWTPs if microalgae can consume 75% of total nitrogen (Ntot) and produce at least 13.5 and 2.4 tonne O2/day in Västerås and Uppsala respectively. The sensitivity analysis showed that minimal volumetric algal yield of 0.15 kg/m3 ,day and 0.25 kg/m3 ,day is required for Västerås and Uppsala respectively, when oxygen production rate of 1.92 kg O2/kg microalgae is assumed. Furthermore harvested and co-digested algae with sewage sludge contributes to significant increase of biogas production and negligible transportation energy increase. The second design of open algal pond for reject water (OAPRW) aims to cultivate microalgae on reject water with high concentration of nutrients, generated in sludge centrifuge. The model assumed high algal growth due to excessive amount of nutrients and increased water temperature to 24°C. Results show a possible 23% and 20% electricity saving on blowers in the biological treatment in Västerås and Uppsala respectively. Both models have positive impact on energy balance in all WWTPs, however MAASPBR has greater uncertainties, because this type of photobioreactor has not been tested unlike OAPRW which has been tested in pilot plant scale.

Balinis vėžlys (Emys orbicularis L.) – plačiai paplitusi, tačiau didžioje savo arealo dalyje nykstanti, reta, Lietuvoje ir daugelyje Europos valstybių saugoma rūšis. Pagrindinės šios rūšies nykimo priežastys - vandens ir sausumos buveinių nykimas dėl sukcesijos ir žmogaus veiklos, populiacijų izoliuotumas, plėšrūnų poveikis, mažas veisimosi efektyvumas ir to pasėkoje nepakankamas populiacijų pasipildymas jaunais individais. Balinių vėžlių apsaugai Lietuvoje turi būti sudarytas ekologinis tinklas, kuriame pagal svarbą būtų išskirtos teritorijos priklausomai nuo jose gyvenančių balinių vėžlių populiacijų skaitlingumo ir ilgalaikio išgyvenimo galimybės tam, kad užtikrinti svarbiausioms iš šių teritorijų apsaugos statusą ir pagerinti balinių vėžlių migracijos sąlygas. Kad užtikrinti tinkamą balinių vėžlių apsaugą reikia taikyti ir kitokias priemones: reguliarų buveinių tvarkymą, dėčių apsaugą nuo plėšrūnų, visuomenės informavimą. / European pond turtle (Emys orbicularis L.) is a widely spread species, declining in a vast part of it‘s range, rare and therefore needs protection in Lithuania and many other European countries. The main reasons of it‘s decline are the lack of suitable water and terrestrial habitats due to succession and human action, impact of predators, little reproduction efficiency and, consequently, lack of young individuals of reproductive age. To protect this species in Lithuania ecological network should be formed, which would include important European pond turtles‘ habitats, where large enough and viable populationas are found. So protection status of the most importatnt habitats would be secured and migration conditiond improved. To make proper pond turtle protection also other conservation tools, such as regular habitat management, nest protection, public conveyance should be applied.

This study investigated the relationship between flood duration of beaver ponds in eastern Ontario and their productivity for waterfowl. The primary objective was to assess the effect of removing water from a beaver pond for one year had on the subsequent productivity of the wetland. Productivity was estimated by sampling water chemistry, standing crops of aquatic invertebrates, vertebrates, algae and vegetation composition and distribution in naturally occurring and managed beaver ponds of varying ages during 1994 and 1995. Three ponds in each of the following categories were sampled; managed ponds reflooded in 1993, managed ponds reflooded in 1991, naturally occurring beaver ponds reflooded in 1992-93, and naturally occurring old flood ponds ($>$5 years old). / Results from this study indicate that beaver pond productivity is negatively affected by flooding duration. Removal of a portion of the beaver dam on old flood ponds may be an effective means of rejuvenating the wetland. Positive effects on the productivity of the wetland should be realized for several years after reflood. Variability in results indicates that other environmental variables were also affecting the overall productivity of beaver ponds. (Abstract shortened by UMI.)

Melt ponds greatly increase the transmission of solar radiation through sea ice relative to snow covered or bare ice. This rise in transmittance has the potential to enhance water column heating and primary production. I examine how spatially variable sea ice surfaces control the under-ice salinity, temperature and photosynthetically active radiation (PAR) and provide estimates of solar heating and primary production during melt. Conductivity, temperature and PAR profiles were measured in the Canadian Arctic under snow covered ice, leads, bare ice and melt ponds. The under-ice light field to a depth of 10 to 13 m was highly variable, controlled by increased transmission under melt ponds and shading by bare ice. Below, the light field became relatively homogeneous showing the depth the surface heterogeneity had an effect on transmitted PAR. Furthermore, one water column profile is not representative of the PAR, salinity or temperature under a spatially heterogeneous surface.

The purpose of this creative project was to develop a master plan for a 450-acre site based on the recently published Land and Natural Development (LAND) Code: Guidelines for Sustainable Land Development by Diana Balmori and Gaboury Benoit. Balmori and Benoit present environmentally conscious design principles that serve as a demonstration for tangible ways to create sustainable landscapes that balance function with the need to preserve natural resources. The outcome of this project includes a detailed master plan for a 450-acre portion of Goose Pond Fish and Wildlife Area (GPFWA) located in Linton, Indiana, which serves as a model for sustainable site design in addition to offering interpretive and recreational opportunities within the focus area. / Department of Landscape Architecture

Melt ponds greatly increase the transmission of solar radiation through sea ice relative to snow covered or bare ice. This rise in transmittance has the potential to enhance water column heating and primary production. I examine how spatially variable sea ice surfaces control the under-ice salinity, temperature and photosynthetically active radiation (PAR) and provide estimates of solar heating and primary production during melt. Conductivity, temperature and PAR profiles were measured in the Canadian Arctic under snow covered ice, leads, bare ice and melt ponds. The under-ice light field to a depth of 10 to 13 m was highly variable, controlled by increased transmission under melt ponds and shading by bare ice. Below, the light field became relatively homogeneous showing the depth the surface heterogeneity had an effect on transmitted PAR. Furthermore, one water column profile is not representative of the PAR, salinity or temperature under a spatially heterogeneous surface.

Darbo aktualumas: Mokslinėje literatūroje pateikiama daug duomenų ir informacijos apie žuvų auginimo ypatumus žuvininkystės ūkiuose auginat žuvis pramoniniu būdu. Sodybiniai vandens telkiniai savo ruožtu įrengiami ir žuvys jose auginamos bei veisiamos šių telkinių savininkų nuožiūra. Trūksta mokslinių tyrimų ir metodinės literatūros analizuojančios sodybinių vandens telkinių įrengimo bei jų pritaikymo mėgėjiškos akvakultūros vystymui, problematiką, todėl ši sritis nusipelno išsamesnės mokslinės analizės. Darbo tikslas: Išanalizuoti sodybinių vandens telkinių įrengimo, jų priežiūros bei žuvų auginimo sodybiniuose vandens telkiniuose ypatumus. Darbo uždaviniai: 1. Apibrėžti dirbtinių vandens telkinių įrengimo teisinį reglamentavimą, atlikti sodybinių vandens telkinių įrengimo projektų vertinimą. 2. Aprašyti sodybiniuose vandens telkiniuose auginamas žuvų rūšis ir aptarti jų auginimo sodybiniuose vandens telkiniuose specifiką. 3. Atlikti vandens telkinių vandens fizinių savybių, cheminės sudėties ir mikrobiologinius tyrimus bei pateikti sodybinių vandens telkinių vandens kokybės vertinimą. 3. Nustatyti su sodybinių vandens telkinių priežiūra, žuvų veisimu ir auginimu susijusias problemas bei pateikti rekomendacijas problemų sprendimui. Išvados: 1. Tiriami sodybiniai vandens telkiniai įrengti pagal suderintus nesudėtingus vandens telkinių įrengimo projektus prisilaikant LR Aplinkos apsaugos įstatyto ir kitų teisės aktų reikalavimų. Sodybinių vandens telkinių įrengimo metu... [toliau žr. visą tekstą] / It is hard to imagine a Lithuanian country district with no pond. Recently the owners of the ponds more and more often select the homestead ponds which are well adapted to the amateurish fish breeding, growing and recreation. It is important, while setting such homestead ponds, to understand the biology of separate fish breeds and to realize the pond as individual and complex ecosystem. Homestead ponds and the water quality need to satisfy biological features of fish and to secure their wellness and nutritional quality. This demands a good knowledge and appropriate competency of the owners at such spheres as pond equipment, fish breeding, fish growing, fish additional feeding, evaluation of water quality and etc. Scientific literature supplies plenty of data and information about peculiarities of fish growing at the fishery farms where the fish are cultured in an industrial way. The homestead ponds are set and the fish are grown and bred at the discretion of the owners. This sphere deserves particular scientific analysis because of the lack of scientific investigations and methodological literature which analyzes the topic of pond equipment and adjustment for the development of amateurish aquaculture. The aim of this study is to analyze the peculiarities of pond equipment, observation and fish growing in the ponds. In order to reach the goal several tasks which include definition of the juridical regulation of pond equipment and evaluation of pond equipment projects were made... [to full text]

This thesis establishes residence time distribution (RTD) as a key tool for the investigation of water treatment systems. RTD software for tracer data modelling and interpretation is developed and validated for problem solving purposes in water treatment systems. The technique focuses on the systematic interpretation of RTD data using a tanks-in-series based model and an indicator, flushing time (tf ). This approach removes the subjectivity often associated with RTD interpretation and is tested extensively using experimental and numerical data. The influence of design elements, intended to enhance hydraulic efficiency, is also addressed. For this purpose, both numerical modelling (Mike 21) and the proposed approach are employed. Results reveal that the interpretive provides valuable information, facilitating a greater understanding of the hydraulic effects of changes to geometry and inlet/outlet configuration than other techniques alone. The approach was shown to be particularly successful at interpreting RTD curves from stormwater treatment systems due to their susceptibility to stagnation. However, it was shown to have limited applicability in systems with complex flow characteristics (such as large bioreactor vessels) or those susceptible to extensive short-circuiting. The approach was also found to be unsuitable for evaluating the impact of deviations from ideal flow on pollutant removal in systems governed by complex biokinetic reactions.