Sökning: "nitrogen budget"
Visar resultat 1 - 5 av 17 avhandlingar innehållade orden nitrogen budget.
1. Assessing reactive nitrogen flows in European agricultural systems
Sammanfattning : In most ecosystems, nitrogen is a scarce and growth-limiting nutrient. Natural and anthropogenic processes convert unreactive atmospheric dinitrogen (N2) into reactive, bioavailable, nitrogen. LÄS MER
2. Nitrogen Losses from a Clay-rich Soil used for Cereal Production in south-western Sweden
Sammanfattning : Addition of fertiliser nitrogen (N) in crop production increases yields and protein contents, but all is not taken up by the crop. Instead, some of the N is lost to air and waters, contributing e.g. to climate change, stratospheric ozone depletion, eutrophication and acidification. LÄS MER
3. Silicon cycling in the Baltic Sea : Trends and budget of dissolved silica
Sammanfattning : The dissolved silicon (DSi) has a crucial role for growth of a large group of primary producers – diatoms and, hence, impact on functioning of the aquatic food web. This thesis contributes to an increased understanding of the modifications of the DSi cycling in the Baltic Sea. LÄS MER
4. On the role of terrestrial ecosystems in a changing Arctic
Sammanfattning : The global temperature rise is proportional to the cumulative amount of CO2 emissions to the atmosphere. This observation is consistent between climate models and historical observations. LÄS MER
5. Nutrient cycling in agroecosystems: nitrogen cycling in southern Sweden in the 1850s and two Tanzanian villages in the 1990s
Sammanfattning : This study presents a general model for analysing nutrient cycling in agroecosystems. The focus is on food production intensity, human carrying capacity, sustainability and efficiency. The model can be used on systems including different kinds of land uses, which makes it applicable for studies on different scales. LÄS MER
