Sökning: "jordbruksmark"
Visar resultat 16 - 20 av 27 avhandlingar innehållade ordet jordbruksmark.
16. Conditions for resource-efficient production of biofuels for transport in Sweden
Sammanfattning : Transportation has continued to increase worldwide and fossil-fuel dependency is strong which leads to a number of problems, e.g. increased emissions of green-house gases (GHG) and risks related to energy security. Biofuels have until now been one of the few renewable alternatives which have been able to replace fossil fuels on a large scale. LÄS MER
17. System studies of biogas production : comparisons and performance
Sammanfattning : Biogas has the potential to be part of the transition towards a more sustainable energy system. Biogas is a renewable energy source and can play an important role in modern waste management systems. Biogas production can also help recirculate nutrients back to farmland. LÄS MER
18. Tracing environmental change and human impact as recorded in sediments from coastal areas of the northwestern Baltic Proper
Sammanfattning : The eutrophication of the Baltic Sea due to increased anthropogenic nutrient loads during the 20th century is well documented and studied. However, in the Baltic Sea drainage area, humans have affected the environment longer than the environmental monitoring can provide data for. LÄS MER
19. The impact of past land-use change on floristic diversity in southern Sweden : a quantitative approach based on high-resolution pollen data
Sammanfattning : This thesis explores the relationship between land-use and floristic diversity over the last three millennia in the uplands of southern Sweden. A quantitative approach based on high-resolution pollen data was applied, using the Landscape Reconstruction Algorithm (LRA), historical maps/aerial photographs, palynological richness and new ways to estimate past evenness at regional and local spatial scales, which enable estimates of the rate and degree of change in land-use and floristic diversity. LÄS MER
20. A palaeolimnological study of the anthropogenic impact on dissolved organic carbon in South Swedish lakes
Sammanfattning : During the past three decades, increases have been observed in dissolved organic carbon (DOC) concentrations and colour in the surface waters of lakes and rivers in parts of Europe and North America, raising concern about the effects on the quality of aquatic environments with consequences for biodiversity, resource availability and recreational use. Various hypotheses have been put forward to explain the recent increases in DOC concentration and numerous studies have been published linking them to declining anthropogenic atmospherically deposited sulphur. LÄS MER