Sökning: "mineral nutrients"
Visar resultat 31 - 35 av 43 avhandlingar innehållade orden mineral nutrients.
31. The role of biological processes in base cation supply in boreal forest podzols
Sammanfattning : This thesis describes experiments designed to improve understanding of biological processes contributing to supply of base cations and other nutrients in boreal forest podzols. We used microcosms containing tree seedlings growing in natural substrates, a combination of direct measurements, modelling, stable Mg isotope analysis, and 13CO2 pulse-labelling. LÄS MER
32. Impacts and drivers of insect herbivory on element cycling in forests globally
Sammanfattning : The effects of insect herbivores on forest functioning are not well understood even though they can have important impacts on ecosystem processes by intercepting foliage before resorption and depositing nutrient-rich materials to the soil. In this thesis, I investigated the impact and drivers of insect folivores on carbon (C), nitrogen (N), phosphorus (P) and silica (Si) cycling in broadleaf forests, and how this varies with major climate variables. LÄS MER
33. Chemical Properties of FBC Ashes
Sammanfattning : In this thesis several aspects of ash chemistry are discussed. An issue of primary concern for boiler operators is the formation of ash deposits. New biomass fuels are introduced, many of which have unfavourable ash melting behaviour due to high levels of alkali metal species and chlorine. LÄS MER
34. Technology and systems for stump harvesting with low ground disturbance
Sammanfattning : Tree stumps could make a significant contribution to the transition from a fossil- to a bio-based economy, but current stump harvesting operations have adverse ecological effects. The ground disturbance caused by the up-rooting leads to increased carbon emissions from the soil and increases risks of leaching of heavy metals and nutrients, while removal of stump wood increases nutrient removal and reduces amounts of dead wood in the forest. LÄS MER
35. Integrated sewage sludge treatment scenarios – techno-economic analysis on energy and phosphorus recovery
Sammanfattning : Sewage sludge is a by-product of wastewater treatment that simultaneously gathers contaminants, valuable organic matter, and nutrients. The treatment of the increasing amount of sewage sludge is important from both pollution prevention and resource recovery perspectives as i) large shares of mineral phosphorus, listed as a critical raw material, terminate in the sewage sludge, and ii) energy recovery from sewage sludge can cover the energy-intensive demand of the treatment process. LÄS MER
