Då naturlig mark görs om till hårdgjord yta i samband med bygge av vägar och bostadsområden ökar flödesbelastningen till närliggande sjöar och vattendrag. Vattenmassorna tar med sig de föroreningar som bland annat finns inbyggda i byggnadsmaterialet, som kommer från trafiken eller från verksamheter som till exempel industrier eller djurhållning. För att förhindra att föroreningarna sprids till de naturliga vattendragen kan åtgärder sättas in för att rena vattnet innan utsläpp till recipienten. Detta kan åstadkommas med hjälp av till exempel så kallade dagvattendammar. Den främsta processen för rening i dagvattendammar är sedimentation. In till dammarna kommer vanligtvis stora mängder partiklar och suspenderat material till vilka föroreningar, som till exempel näringsämnen och metaller, kan fästa.

Erosion är en ständigt pågående process som formar om vårt landskap. Längs med kusten pågår ett samspel mellan vind, vågor, strömmar och sediment. Ett område kan sägas vara utsatt för erosion om mängden borttransporterat material är större än den mängd som avsätts. Det omvända kan också inträffa, det vill säga att stränder växer. Detta kallas för ackumulation.

The Earths climate is changing at a higher rate, i.e between 1861 and 1994 the annual mean temperature in Scandinavia increased with 0,68º C and according to recent climate models the annual mean temperature is likely to rise with another 3º C during this century.A warmer climate in many ways is associated with changing conditions for lake ecosystems. An expected higher water temperature and a stronger summer stratification of the water column increases the risk of anoxic conditions at the lake bottom. Thus anoxic conditions are likely to cause a phosphate leakage from the sediment, i.e. a higher internal loading of phosphate.In this project, the extremely warm summer of 2002 has been used as an example for a possible scenario for a future climate. By comparing levels of phosphorus in the summer of 2002 with a ten-year median value, a phosphorus related sensitivity to climate change has been analyzed for 55 Swedish lakes.

The mining industry, in terms of ore excavation and metal production, is and has been important to the Swedish economy. In connection with the ore excavation process, large amounts of partly sulphidic waste are produced. When the metal sulphides are exposed to air and water they are eventually oxidised, which leads to the formation of acidic water with high concentrations of metal cations and sulphate ions, so called Acid Mine Drainage (AMD). This water may reach the nearest surroundings and cause negative environmental effects. By covering the waste with soil or water, the oxidation process can be minimised. At the Rävlidmyran mine in the county of Västerbotten open pit mining took place between 1951 and 1991.

När en kommersiell hamn byggs ut fordras omfattande muddringsarbete för att säkerställa ett brukligt djup för sjöfart. Då stora delar av muddermassorna ofta är förorenade av tungmetaller och miljögifter krävs särskilt omhändertagande av dessa. Traditionella omhändertagningsalternativ består av att deponera massorna på särskild avsedd plats på land eller tippa till havs, något som inte tillåts för förorenade sediment. En relativt ny metod är stabilisering/solidifiering (S/S) som innebär att muddermassorna behandlas med ett bindemedel för att sedan kunna användas som fyllnadsmaterial i exempelvis kajkonstruktioner. Dessa alternativ behöver noga vägas mot varandra med hänsyn till ekonomiska och miljömässiga aspekter.

This master thesis was conducted in order to investigate the effects of the browsing species Yeheb on animal tissues in Swedish landrace goats and to make a literature review in order to increase the knowledge of the importance of this plant for livestock production in Somalia. The evergreen Yeheb bush is a very important feeding source for grazing and browsing animals in Somalia during the dry period. Yeheb contains cordeauxiaquinone that stains the bones of the animals red/pink, which has been an increasing problem when exporting meat to foreign countries. In an experiment, two goats were fed dry and fresh leaves from the Yeheb bush for one and two months, respectively. The goats did not feed the intended amount of dry leaves, since the supply and palatability was not as high as estimated.

Ekförgiftning orsakas av att djuren äter antingen ekollon eller eklöv. Förgiftningssymtomen och skadorna orsakas av en substans som kallas tanniner. Tanniner delas in i två huvudsakliga grupper, de kondenserade och de hydrolyserbara. Det är främst de hydrolyserbara tanninerna som är skadliga detta beror på att de lätt påverkas av de enzymatiska processerna i våmmen hos idisslare, och de produkter som bildas vid dessa processer är vattenlösliga och tar sig lätt ut i vävnaderna. De skador som främst ses vid ekförgiftning hos idisslare är ulcus i gastrointestinalkanalen, akut tubulär nekros och leverskador.

The aim of the study was to map the extent of Fe, Cu, Pb, As, Zn and S contamination in the area surrounding the Nasa silver mine. The mine operated between 1635 and 1810 with some prospecting performed in 1889, and has become infamous for the gruesome ways that the indigenous people were treated during the early years of operation. This study tested three hypotheses through a geochemical survey: 1) sulfide oxidation is still active in the abandoned mine, 2) the soil downslope of the mine is contaminated by mine drainage, and 3) the stream downslope of the mine is affected in the same way. All three hypotheses were valid, as the results showed that still, >200 years after mining operations ceased, signs of the historical mining are clearly visible in the surrounding environment. Acidic conditions were discovered in surface waters close to the waste rock piles, which indicates active sulfide oxidation.

Benthic invertebrates play important roles as feeding resources for many organisms in different food webs. Shifts in predation of these organisms can generate cascading effects and potentially lead to the disappearance of one or more species from a site. Cascading effects can bring impacts to organisms who aren?t even directly involved, why studies in this field are important for understanding sudden changes in ecosystems. I examined the predation from fish and waterfowl on benthic invertebrates in the shallow and eutrophic Lake Tåkern in the plains of Östergötland County, southern Sweden.

Kantzoner mot vattendrag är av stor betydelse för att upprätthålla eller förbättra vattenkvaliteten i våra vattendrag. De strandnära zonerna fungerar som reservat i skogen med stor biologisk mångfald. De utgör barriärer för näringsämnen, löst organiskt kol, sediment, kvicksilver och andra miljögifter. Trädens rötter armerar jorden närmast vattendraget och minskar erosion och sedimentation. Syftet med detta arbete har varit att beskriva varför kantzoner bör användas och hur bredden på kantzonen, med hjälp av en modell i ArcMap, kan anpassas efter förhållandena runt vattendraget.

The vegetation?s impact on erosion control is widely explored, even though research? results are scattered where it suggests a both positive and negative relationship between roots and erosion tendency. Research has measured the roots? impact on erosion by many different methods, hence the aim of this study is to offer a clearance of what factors play an important role in the choice of appropriate species controlling river bank erosion. I have therefore studied 17 articles concerning vegetation and erosion control, which were found in different databases such as: Web of Knowledge, Biological Sciences, Academic Search Elite and Google Scholar.

Benthic invertebrates play important roles as feeding resources for many organisms in different food webs. Shifts in predation of these organisms can generate cascading effects and potentially lead to the disappearance of one or more species from a site. Cascading effects can bring impacts to organisms who aren?t even directly involved, why studies in this field are important for understanding sudden changes in ecosystems. I examined the predation from fish and waterfowl on benthic invertebrates in the shallow and eutrophic Lake Tåkern in the plains of Östergötland County, southern Sweden.

Antifouling paint containing the biocide bisTributyltinoxide (TBTO) has been used since1960 to reduce the occurrence of fouling on hulls on boats/ships. January 1st, 2003 theantifouling paints containing TBTO were prohibited. This ban covered all use of paintcontaining the substance TBTO. The ban was introduced because of alarming observationssuch as development of imposex in aquatic non-target organisms. Imposex is the impositionof male sexual characteristics on mainly female marine snails and occurs due to exposure toTributyltin (TBT).

This literature study concerned the use and function of the radioactive isotope carbon-14, as a dating method of organic material, within the scientific field of physical geography. In this report it is presented the need of atmospheric calibration curves and the development of these as a necessity to translate carbon-14 years to calibrated calendar years. A number of common age-depth models that is used to give an approximation of an accumulation sequence and its related dates over the actual time period in different natural archives is presented and discussed. Different problems that commonly occur when age-depth models are utilized as for instance reservoir effects, contaminations or other age deviations are addressed and analyzed. The software CLAM in presented and discussed and was also used to produce age-depth models.

Sedan industrialiseringen har koncentrationen metan i atmosf?ren ?kat. Metan (CH4) ?r en effektiv v?xthusgas, producerad av metanogena organismer i syrefria milj?er. K?llorna till CH4 varierar brett och ?r b?de antropogena och naturliga.