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4695 Uppsatser om Water environment - Sida 5 av 313

Hot och risker med dricksvattenförsörjning : Förutsättningari tid och rum för bevarande av Sundsvalls och Timrås dricksvattenförsörjning

This study describes what impact activity within Wifstas, Matfors,Grönstas and Nolbys water protection areas have on the quality of the drinkingwater. It considers the use of the area, environmentally dangerous activitiesin the past and present, the geology?s part, what harm hydroelectric power damsmay cause if they break and how climate change might affect the area in thefuture. It also takes into consideration activities outside the waterprotection areas which might have a suspected impact on the water quality. Theresults of the study are that pollution from infrastructure such as roads, orwastewater from treatment plants may cause occasional contamination of thedrinking water, foremost due to flooding.

Nursing technique and growth environment of Rabbit fish (Siganus guttatus) in the area of Tam Giang lagoon, Thua Thien Hue

SummaryIn the area to the east of Hue city, in Vietnam, lays Tam Giang lagoon, one of Asia's largest lagoons, with an area of 22,000 hectares. This lagoon is suitable for aquaculture. One reason for this is because the salinity differs from sweet to salty in different parts of the lagoon. The Vietnamese Government advocates an increase in environmentally-friendly aquaculture and the fish Siganus guttatus (Rabbit fish) is a candidate for this. This fish eats mainly algae and can be cultivated in a polyculture.

Vilken preferens har tjockskalig målarmussla (Unio crassus) för bottensubstrat och vattenhastighet i Storån, Östergötland?

The thick shelled river mussel (Unio crassus) has a fragmented distribution in southern Sweden. It is a threatened and protected species. In both the Swedish red list and the IUCN Red List of Threatened Species Unio crassus is classified as Endangered (EN). Causes for this classification are for instance differentiated bottom substrate and deterioration in water quality. In this study, habitat preferences of Unio crassus were investigated to assist in future restoration work.

Förskolebarns tankar om vattnets kretslopp i naturen och i samhället. : skiljer sig pojkars och flickors svar åt?

AbstractThe work will give the picture of what four- and five-year-olds know about the water cycle in nature and in the society. Is there any difference depending on whether a boy or a girl is answering? The work will as well try to describe a picture of how a pre-school could plan their work on a sustainable society, science, and increased gender equality. To answer these questions the information has been received from interviews with children and by studying pre-school?s local plan.    Earlier research on the area of water shows that it is important before working with a new topic to find out what knowledge the children already have, so that the process could be as worthwhile as possible.

Forest and water governance in Sweden

Water related problems are highlighted as a challenge to sustainable development and the topic of forests and water is gaining increased attention worldwide. Governing forest and water is a complex issue, as the interactions are affected by policies and actors from multiple levels and sectors. In Sweden, forests cover much of the land and forestry is an important land-use, inevitably impacting the water in the landscape. This study aims to understand and explain the existing governance framework around forestry and water in Sweden. Based on the Policy Arrangement Approach, the study?s research questions focused on the actors involved, the formal and informal rules, the resources and power structures and the discourses related to forestry and water in Sweden.

Ut ur Östersjön genom vassen : beskrivning av övergödningsproblematiken samt optimering av en reningsmetod genom skörd av vattenväxter

This study is based on AgroSeas business idea from environmental problems to valuable resource, with the objective to optimize a method to purify the already eutrophicated Baltic Sea by harvesting water plants, mainly reed. The nutrients will then be recirculated to arable land through residues from biogas production. The amount of nutrients that can be removed by harvesting the biomass depends on the amounts of biomass and the nutrient content of it, which in turn is strongly dependent on the nutrient concentration of the surrounding water. Vegetation suggested in the study for an effective nutrient uptake is helophytes: reed, cattails, reed canary grass, reed sweet grass in shallower water and lemnoideaes: duckweed and nymphaeids in the deeper parts. Competitive species has high purification ability but requires regular maintenance to avoid channeling and overgrowth. Regarding time and method of harvest, effectiveness may be improved by: harvesting plants above the water level and after flowering, a border is kept, harvesting twice a season, a bigger machine and a regular maintenance. This literature has illuminated a major environmental problem and it has been suggested optimizations for a method for cleaning the Baltic Sea through harvesting water plants, but to get a definite answer for the optimal method for each site tests should be carried out, this because many factors determine to what is suitable for each, specific environment. .

Ligger bäckarna rätt i kartan?

?Are the headwaters streams at the right position in the map? is a study that has been performed on behalf of Holmen Forest, region Örnsköldsvik. This study will be the basis for deciding if the Hydrology Layer Property map or Holmen Forest map will be used for planning nitrogen fertilization in forestry. The background to this study is that nitrogen fertilization near water will increase the risk of nitrogen leaching out into the water systems, which has a negative impact on the environment. The headstreams positions have been recorded in the field with a GPS and the data analyzed in the geographic information system ArcMap.

Hållbar vattenförsörjning i områden med vattenbrist : Sustainable water supply solutions for areas affected by water shortage

In some coastal areas in Sweden water shortage sometimes appears because the withdrawal of groundwater is greater than the groundwater recharge. It creates a situation where the available groundwater is insufficient to support residents and businesses with drinking water. The high withdrawal of groundwater also creates a risk for saltwater intrusion to drinking water wells. The problem most commonly occurs during the summer when the groundwater recharge is low, but the population is high, due to tourism and summer residents.The purpose of this study was to investigate how local water supply in areas affected by water shortage can be solved as sustainable as possible. The work was divided into three parts where the first part comprised of a literature review on water systems in which four different options were investigated: artificial groundwater recharge, rainwater harvesting, desalination and water reuse.

EU:s medborgarinitiativ : En framkomlig väg för att minska det demokratisk underskottet?

The European Union is struggling to maintain democracy and tries to increase the participation among the citizens in Europe. The European Citizens? Initiative, ECI, is a platform established by the European Commission to allow citizens to propose new legislation. ?Water and sanitation are a human right! Water is a public good, not a commodity!? is the first ECI that has met the requirements.

Små vatten- och avloppssystem : Möjligheter till inskränkning av verksamhtesområden

This study is focused on small scale water and wastewater handling in Sweden. The study is divided into two major parts; the first describes common methods for water- and wastewater handling and the second part is a case study on three small and expensive systems in Gällivare municipality, in the north of Sweden. In the case study, abilitys for the local government to hand over unwanted systems to the water users is investigated and found to be a plausible solution to cut costs for two out of the three studied systems. In the third case, water and wastewater systems is not recommended to be handed over but other ways of cutting costs are suggested..

Dagvattenhantering i den täta staden

This thesis adresses the subject of stormwater management and the problematic with stormwatermanagment and landuse in the compact city. The thesis research different solutions in stormwater managment and how to implement them in the context of the compact city. And at the same time preserve and make good recreaational places and keep quality green land per capita. The thesis also analyses risks and problems that could effect the environment with focus on stormwater managment and hov to minimize these problematic factors an create a good environment. In an urban context where the water has a natrual place, and is used as a asset.

Brunnsviken : Utvärdering av åtgärder för förbättrad vattenkvalitet

Periods of hypoxia are a recurring issue in Brunnsviken. Main factors that trigger hypoxia in Brunnsviken are eutrophication  due to anthropogenic emission of nutrients, stratification in the water column due to salinity and temperature differences  that prevents mixing and a sill inlet that prevents water exchange. As an attempt to improve the oxygen levels, bottom water is pumped from Brunnsviken causing aerated surface water to flow back into the basin.  The objective of this Master?s thesis was to study the change in dissolved oxygen levels due to pumping.

Inventering av processvattenbalans : fastställande av fjärrvärmedistributionens läckage inom Vattenfall Värme Uppsala AB

Heat is distributed to the district heating customers through pipes with water as a heat carrier. The district heating system is complex. To decide what is leakages from the district heating net versus what is the water consumption of the plant, is difficult. Therefore, the purpose of this master thesis is to establish a model where the district heating net?s leakages but also the water consumption of the plant can be followed daily. The project is performed at Vattenfall´s district heating power plant in Uppsala. Information is gathered through discussions, drawings of the plant and guided tours of the plant.

Vattenjärnhaltens betydelse för mjölkkors hälsa och produktion :

Drinking water from drilled wells has a high content of iron and other minerals in many places in Sweden. Questions about the association between the quality of drinking water and the health of dairy cows are regulary asked both by advisers and dairy farmers. There are so far not many studies published about the relevance for high iron content in water and dairy cow health and production. Therefore, the aim of this study was to investigate if there is a connection between the iron content in water and the health of dairy cows. Initially a literature study was made about iron and it´s function in ruminants.

Skötselåtgärder vid nyetablering av skyddszoner vid bäckar i södra Värmland :

Buffer zones play an important role for the water quality in our watercourses. When harvesting a forest close to a watercourse a buffer zone should be left. When it's not left, it will lead to radical changes in the environment for the water organisms. The overall purpose of this thesis was to illuminate the production- and environmental thinking when establishing new buffer zones in south of Värmland. The partials goals were to determine choice of tree species, ways of regenerate, occurrence of soil scarification and the occurrence of machine tracks in newly established buffer zones.

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