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177 Uppsatser om Aquatic pollution - Sida 4 av 12

Identifiering av fosfatfosfors käll- och flödesfördelning i ett litet jordbruksområde

Eutrophication of lakes and streams are nowadays a well known environmental problem and implies an enrichment of the nutrients phosphorus (P) and nitrogen (N). Phosphorus is considered to be the most important component for the growth of aquatic plants and leads in too large quantities to an intensification of growth. Phosphate (PO4) is the fraction of phosphorus that can easiest be taken up by plants and thus have the greatest impact on eutrophication. Increased plant growth in lakes and unfavorable conditions for aquatic animals are two examples of negative consequences. A significant portion of the increased nutrient supply to nearby water can be derived to phosphate leaching from agricultural areas, where private sewers and agriculture is two main sources.

Mixture and single-compound toxicity using Daphnia magna : comparisons with estimates of concentration addition and independent action

Aquatic organisms are usually not exposed to single substances but rather to mixtures of toxicants in streams located in agricultural areas. The transport of pesticides used in the agricultural area in Sweden is monitored with continuous environmental supervision every year. During 2002-2008 an average of 10 pesticides were found in each sample and 40% of the samples contained substances with concentrations higher than the Water Quality Standards. Chemical risk management is normally based on single-test evaluations. A problem when assessing mixture toxicities is that the constituents and concentrations of pollutants in the environment vary greatly.

Näsnarens framtid i ett näringsstatusperspektiv

Eutrophication has been a problem in aquatic systems for a long time. It is well known that the key nutrient to control the eutrophication process is phosphorus. Lately, it has been possible to reverse the process and recover lakes from eutrophication.During a long time Lake Näsnaren in Katrineholms kommun, Södermanland, has been exposed of a large amount of phosphorus from the city's wastewater. The lake has a great value as a habitat of rare species but also a high recreation value for people living in Katrineholm and Södermanland. Lake Näsnaren is situated in a Natura 2000 area.

Aerosolers dygnsvariationer och långväga transporter

This work aims to obtain information on diurnal variations of aerosol concentrations in thecity of Lund (Sweden) and trying to locate the origin of the aerosols long distance transports.The study shows that the aerosol concentrations varied quit strongly over the entiremeasurement period, reflecting air masses of different degrees of pollution, mainly as a resultof the diurnal rhythm of the traffics. Trajectories reveals that air masses originated inSoutheastern and Eastern Europe contains higher aerosol concentrations compared to other airmasses..

Öppen dagvattenhantering i urbana miljöer :

Storm water causes a number of problems in our country, particularly in city environment with its surfaces of non-absorbing ground materials. At heavy rain falls there are floods due to lack of capacity in the drain system when meeting heavy water masses over a short time. When the drain system is overloaded huge water masses reach the recipient untreated and there causing disturbances in the aquatic ecosystem. Due to emissions from mainly traffic, industries and other human activities the storm water is polluted. Earlier the problem used to be solved technically, by increasing the capacity of the tubes and by construction of reservoirs to delay the floods peaks.

En jämförelse av energiåtgång och emissioner för olika persontransportslösningar i Stockholm stad

This master thesis sets out to compare the different public transport modes in Stockholm city.Both energy consumption and air pollution are compared. The chosen transport methods are car,bus and metro.Traditionally the rail industry has had environmental arguments as a strong competitiveadvantage when it comes to passenger transportation. However, in recent years the automotiveindustry has been getting more positive media attention regarding environmental issues, forexample Roger Kemp?s statement that the car is the most environmental friendly passengertransportation mode in the UK. This study will show the environmental advantages of railwaytraffic in cities.The energy sources of the world are not endless and the use of the different sources affects theenvironment in different ways.

De externa etableringarnas framtid : en samhällsekonomisk analys av behov och möjlighet till politisk styrning och planering

The out-of-town retail establishments are part of the dramatic structural changes in the retailing of food and groceries. There are however strong indications suggesting these establishments result in negative externalities concerning areas such as pollution and urban environment. The purpose of this study is to describe and, from an economic perspective, analyse the Swedish political regulations and planning policies concerning the out-of-town supermarkets. The analysis establishes that the current regulations regarding out-of-town retailing do not, due to the occurrence of market failures, produce an optimal situation. It might therefore be necessary to change the planning policies in a more restrictive direction.

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.

Förslag till kväverening i Forsåsystemet genom våtmarksetablering

The last hundred years humans have drastically changed the amount of available nitrogen in nature. Today human activities release twice as much available nitrogen as all natural processes are doing together. We also have degraded nature´s possibilities to take care of nitrogen through the draining of wetlands and straightening of rivers. In order to regain the potential of nitrogen retention in the water systems there now requires a reshape of the landscape we live in. A planned expansion of the mining activities in Garpenberg, Dalarna, would double the content of nitrogen in the waters below the mine.

Lokala skillnader i konsumtion av påväxtalger och terrestra löv hos en differentierad population av Asellus aquaticus

That ecological and evolutionary processes can take place on the same time scale is a recent insight. Today we also know that they are directly linked to each other. In the lake Tåkern, in year 2000, there was a structural change when phytoplankton declined and submerged vegetation, mainly stoneworts began to spread. This led to evolutionary changes in the aquatic sowbug, Asellus aquaticus which had previously been limited to the reed, most likely feeding on detritus. But then, sowbugs could exploit the new habitat in stoneworts and a new food resource in terms of periphyton.

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.

Inomhusklimat i skolor- En jämförelse mellan upplevt och uppmätt inomhusklimat

Students? performance in school is dependent on the indoor climate. This report studies four schools regarding air quality and thermal environment. A survey was made at the schools as well as measurements of carbon dioxide, dampness, thermal climate and, as an indicator for the furniture?s capability to collect dust, shelf factor and fleece factor.

En internationell jämförelse av miljölagstiftning avseende växtnäringsläckage med ursprung i jordbruket

SAMMANFATTNINGÖvergödning har de senaste åren blivit en stor och omdebatterad fråga i många EU- länder.Även om problemen har minskat en del är detta inte tillräckligt, vi ser fortfarande fiskdöd,syrefria bottnar och giftiga algblomningar. Hur långt ska vi gå för att kunna övervinnaövergödningsproblemen? Genom olika sorters lagstiftning, ekonomiska styrmedel ochrådgivning har vi nått en bit på vägen, men fortfarande krävs det mycket arbete innan vi haruppnått målet. Jordbruket har pekats ut som en av de största källorna till övergödning pågrund av överskottet av kväve och fosfor som varje år urlakas ur våra jordbruksmarker.Inom EU finns sedan 1991 en gemensam lagstiftning; Nitratdirektivet. Syftet med direktivetär att minska nitratföroreningar och andra föroreningar från jordbruket, då dessa påverkarsåväl yt- och grundvatten som kust- och havsvatten.

CAP ? pengaslukande monster eller effektiv jordbrukspolitik EU:s gemensamma jordbrukspolitik sedd ur tre olika teoretiska perspektiv

The Common Agricultural Policy has been a burning topic for debate for severaldecades. According to the CAP:s opponents it's effects include pollution, market distortionsand not least a huge expense for the European union.In this study we seek to explain why the CAP has remained almostunreformed since it's constitution in the 1950:s. The means by which we do so isa case study where we analyze the CAP by using three different theories; liberalinter-governmentalism, realistic trade theory and new institutionalism.In the final chapter we conclude that the theories complement each other. Newinstitutionalism explains the rigidity of the CAP. The liberal perspective explainsthe origin and the logic behind the policy whereas the realistic point of view putsthe policy in the light of an international economic theory and recognizes nationalpolicy makers roll in the inflexibility of the CAP..

Selecting plant species for the occasion of the 300th anniversary of Carl von Linné at Möckelsnäs :

This report was an outcome of a cooperation between ?The Visitor and Knowledge Project Carl von Linné? and SLU, the Swedish University of Agricultural Science. The aim with the cooperation was to create a garden and to suggest suitable plants for an orangery already built. All species suggested should have a documented relationship with Carl von Linné. The project is located in the southern part of Sweden at an estate named Möckelsnäs not far away from Linné?s birthplace.

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