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40 Uppsatser om Runoff - Sida 3 av 3
Modellering av vattenflöden samt kväve- och fosforkoncentrationer från Krycklans avrinningsområde med HYPE-modellen
HYPE-modellen utvecklades som ett hjälpmedel för att uppfylla målet om att alla svenska vattendrag ska ha uppnått åtminstone god ekologisk status år 2015, enligt EU:s ramdirektiv för vatten. I HYPE-modellen delas avrinningsområdet in i markklasser, som definieras utifrån kombinationen av jordart och markanvändning/marktäckeklass. I modellen finns det många parametrar. Vissa av dem är generella för ett större område eller kan hämtas ifrån tidigare forskning, medan andra måste kalibreras för varje avrinningsområde. De parametrar som kalibreras beror i de flesta fall antingen av jordart eller av markanvändning eller marktäckeklass.Syftet i den här undersökningen var att kalibrera HYPE-modellen för ett mindre avrinningsområde samt undersöka avrinningsvägar och utvärdera den utförda kalibreringen.
Frigörelse av fosfor från färskt, fryst och torkat växtmaterial : ett laboratorieförsök för att öka förståelsen för fosfordynamiken inom växtodlingen
Phosphorus is the single most potent contributor to eutrophication of freshwater and has also been shown to contribute to the toxic algae blooms in the Baltic sea. The
dynamics and paths of losses of phosphorus from arable lands are not fully understood.
It is known that phosphorus can be lost directly from plant material to water.
In studies where plant material has been subjected to several freeze-thaw cycles, large amounts of phosphorus have been lost. Most studies have been conducted
under field conditions, with many factors effecting the measured losses of phosphorus, such as weather and type of soil. This study was performed in a controlled environment without the presence of soil. Instead of soil, small glass beads were mixed with the plant materials in vessels, to make possible homogeneous leaching with water through the mixture of glass beads and plant materials.
In this study, clover, ryegrass and dry straw were cut to pieces, approximately 2 cm long.
Dagvattendammars reningseffekt : påverkande faktorer och metodik för statistisk modellering
Storm water is defined as Runoff from precipitation such as rain or snow. It is collected in sewage disposal systems and since it mainly originates from urban areas it can contain high levels of heavy metals, nutrients and oil etc. Polluted storm water is currently treated by different methods such as wet ponds, constructed wetlands and filter strips. This study investigates these methods, which in earlier studies have shown to give varying results regarding their treatment efficiency.This thesis has been written on commission of SWECO VIAK and was aimed at studying those parameters that may affect the treatment efficiency of nutrients and heavy metals in storm water treatment facilities (STF:s). Through literature studies the dominating treatment processes in ponds and wetlands were examined.
Den positiva hälsovågen : En kvantitativ studie om hälsofrämjande arbete
The construction of buildings and paved surfaces changes the natural water balance.Precipitation generates surface Runoff and storm water instead of infiltrating into the soil.Storm water has come to be considered as a major source of pollution in lakes and streams inthe vicinity of urban areas. Reduction of pollutants in storm water is a key action in order toprotect sensitive recipients and maintain high water quality. Storm water is traditionallytransported by storm sewers to the nearest recipient. In recent years the approach to stormwater management has changed; storm water should primarily be disposed of on site, throughlocal disposal of storm water, LOD. LOD is created by a combination of the function ofseveral smaller local facilities and the general sewer system.
Lokalt omhändertagande av dagvatten i Västerås - Möjligheter till ökad användning i befintliga innerstadsområden : Local disposal of storm water i Västerås - possibilities for increased use in downtown areas
The construction of buildings and paved surfaces changes the natural water balance.Precipitation generates surface Runoff and storm water instead of infiltrating into the soil.Storm water has come to be considered as a major source of pollution in lakes and streams inthe vicinity of urban areas. Reduction of pollutants in storm water is a key action in order toprotect sensitive recipients and maintain high water quality. Storm water is traditionallytransported by storm sewers to the nearest recipient. In recent years the approach to stormwater management has changed; storm water should primarily be disposed of on site, throughlocal disposal of storm water, LOD. LOD is created by a combination of the function ofseveral smaller local facilities and the general sewer system.
Opportunities for improved environmental sustainability of a wine producer in South Africa : natural resource management and climate change adaptation and mitigation
South Africa has been among the top ten wine producing countries for at least 20 years. Even though the land under grapevines is decreasing globally it is still increasing in Africa. The awareness of environment has strengthen the last years and South African producers experience a high demand of environmentally friendly produced wine, especially from the European market. This demand was the driving force behind the development of the world unique sustainability certification, Integrated Production of Wine (IPW), which is inscribed in the South African legislation. What makes this certification unique is that consumers can trace their product all the way back to the farming practices owing to the identity number specified on the IPW Integrity & Sustainability seal on certified products.
Do 25 years old skid tracks restrict growth and survival? : a study on growth conditions for the planted regeneration in a rainforest rehabilitation project
The rainforests of the world are important not only to the countries in which they grow but to the world as a whole. They influence oxygen and water circulation as well as carbon sequestration which in turn affect global radiation and global warming. The forest also have great value and in Malaysia as in many other tropical countries large volumes are harvested which leaves great areas of degraded forest with little growth and biological diversity. Due to their low financial value these forests are often transformed and used for other purposes than forestry such as oil palm plantations.
The trees are often transported out of the forest using large bulldozers. They are heavy which causes compaction of the forest floor and during transport the top soil layers are moved to improve mobility.
Strömmar av vatten och politik - en studie om policyprocesser och anpassning.
One of the distinguishing features of successful societies is the ability to adapt to change, bothsocial but also natural changes like climate change. Climate change is a complex, dynamic,non-linear process with a great deal of uncertainty concerning the time perspective, risks andconsequences. A combination of factors like climate change, geographical vulnerability, adensely populated and highly built up coast line along with factors like deficient handling ofsurface Runoff and a large usage of ground water leads to an increasingly vulnerable society. Italso puts a greater pressure on the society to have preventive measures in place.The number of actors working with preparing society to the expected impacts of climatechange and variability is increasing. However more than half of Sweden?s municipalities donot consider changing climatic conditions when planning, and many times even allow theconstruction of new living areas in known climatically vulnerable areas.
Frigörelse av kvicksilver och metylkvicksilver till bäckvatten under olika perioder efter skogsavverkning :
High levels of Hg in fish in Swedish lakes have been a problem along time in Sweden. The major concern is production and accumulation of the most toxic form of mercury; methyl mercury (MeHg). Consequently, in about half of our 83 000 lakes fish contain concentrations above the recommended limit for human consumption of 0,5 mg mercury per kg fresh weight (most of it in the form of MeHg). Consumption of fish containing too high levels of MeHg may cause problems for both humans and animals.
Three major sources of MeHg in surface waters are: 1) Runoff from terrestrial areas, 2) deposition from the atmosphere, and 3) internal production of MeHg in lakes and streams. The aim of this study was to investigate the effect of clear-cutting on the concentration of Hg and MeHg into draining streams.
Miljökonsekvenser av dagvattendamm i Skebäck, Örebro : en fallstudie hur miljöpåverkan av en dagvattendamm intill ett Natura 2000-område kan bedömas
Stormwater is surface Runoff water that originates from precipitation or snowmelt and that on hardened surfaces prevents to infiltrate the ground. In city areas stormwater can consists of major amounts pollutants and when reaching a lake or watercourse it can cause damages on vegetation and animals. Therefore it is important to treat polluted stormwater before it reaches the recipient.
The municipality of Örebro have since the 90ies an extensive work with treatment of stormwater in sedimentation ponds. A new stormwater treatment project is planned in an industrial estate in Skebäck, Örebro.