Visar resultat 1 - 5 av 64 avhandlingar innehållade ordet pond.
Sammanfattning : Today there is a growing interest in constructed ponds to treat agricultural runoff, sewage water and stormwater. But ponds not only remove nitrogen, phosphorus and pollutants such as heavy metals; they can also have ecological, social and esthetic values. LÄS MER
Sammanfattning : Stormwater, in this study defined as surface runoff in urban areas, is known to transport large quantities of toxic substances to receiving waters. Therefore different practices to treat stormwater have been proposed. In Sweden retention ponds have become a common treatment method during the past decade. LÄS MER
3. Development and Evaluation of a Filter-Bed-Based System for Full-Scale Treatment of Industrial Landfill Leachate
Sammanfattning : It is well known that nature offers an abundance of materials and processes that can be adapted in low-tech fashion, to fabricate systems capable of removing pollutants from wastewater. During the last decade, extensive basic and engineering research on such natural treatment systems have led to improvement of the quality of discharged wastewaters. LÄS MER
4. Three-Dimensional Simulation and Physical Modelling of Flows in Detention Tanks - Studies of Flow Pattern, Residence Time and Sedimentation
Sammanfattning : Improving effluent water quality to receiving waters using stormwater ponds and storage tanks is acknowledged to be an effective method. The performance of the method depends however on flow conditions such as velocity distribution, short-circuiting currents and the volume through which the influent water flows, the so called effective volume. LÄS MER
Sammanfattning : The aim in this thesis was to study the importance of different types of wetlands for the biodiversity in a landscape. The landscapes were both agricultural and urban, and wetlands were in different successional stages. Diving beetles (Dytiscidae) were used as study organisms. LÄS MER