Sökning: "soil temperature"
Visar resultat 16 - 20 av 186 avhandlingar innehållade orden soil temperature.
16. Biogeochemical processes in frozen soils : unfrozen water in frozen soils and factors regulating carbon mineralization at low temperatures
Sammanfattning : High latitude ecosystems are important for global carbon (C) balances and are among the most sensitive ecosystems to climate change. Microbial CO2 production in soil is known to proceed at temperatures < 0ºC in these regions and winter CO2 emissions can significantly affect annual C balances. LÄS MER
17. Microbial life in boreal soils : on the availability and fate of carbon substrates for microbial activity in boreal soils
Sammanfattning : The large pool of carbon (C) stored as soil organic matter (SOM) in soils of high-latitude ecosystems contains more organic C than all global vegetation and the atmosphere combined. Global climate change is expected to have especially pronounced effects in these ecosystems, and even small changes in the accumulation and decomposition of their soil C pool driven by heterotrophic microbial activity could profoundly affect atmospheric CO₂ levels and thus the global climate. LÄS MER
18. Carbon and nitrogen dynamics in agricultural soils : model applications at different scales in time and space
Sammanfattning : An understanding of soil organic carbon (C) and nitrogen (N) dynamics is essential for efficient and environmentally sustainable agricultural production. This thesis includes model studies of C mineralization at regional/national level with annual time steps, N balances at field level with annual time steps, and N dynamics at 34 locations within a single field with daily time steps. LÄS MER
19. Bioaugmentation for reduction of diffuse pesticide contamination : a bioprophylactic concept
Sammanfattning : Pesticides and their residues frequently contaminate surface waters and groundwater so consequently there is a great need to identify methods and practices that reduce such contamination. This thesis examined the potential of a 'bioprophylactic' concept based on the hypothesis that diffuse contamination after application in the field can be significantly reduced if pesticides are degraded as rapidly as possible after the intended effect has been achieved. LÄS MER
20. Greenhouse gas emissions from rewetted extracted peatlands in Sweden
Sammanfattning : Peat extraction for horticultural purposes and energy production has a long tradition in Northern Europe. Related drainage activities directly affect the greenhouse gas (GHG) balance due to oxidative peat decomposition and denitrification, with concomitant emissions of carbon dioxide (CO₂) and nitrous oxide (N₂O). Rewetting, i.e. LÄS MER
