Markmikrobiologi
Soil microorganisms drive the biogeochemical processes that are the basis for life. They provide valuable ecosystem services by having central roles in e.g. nutrient cycling and degradation of organic matter and pollutants. However, proper stewardship of these services requires a firm scientific understanding of core concepts in microbial ecology. This includes defining the relationship between microbial diversity and ecosystem functioning, as well as identifying key organisms and factors that control microbial processes in soil. We address these questions through the integration of fundamental and applied research.
Nitrogen cycling - Sara Hallin
The nitrogen cycle is one of the essential processes necessary to sustain life on Earth in general and agro-ecosystems in particular. The driving forces behind this process are communities of microorganisms that mediate the conversion from one form of nitrogen into another. The structure and activity of these communities are influenced by environmental properties such as pH, salinity, water, carbon and nitrogen content. The dynamics of this interaction is complex when temporal and spatial variations are considered since soil is a very heterogeneous medium. By using a combination of molecular tools, activity measurements, statistical modeling and bioinformatics our aim is to link microbial community dynamics with ecosystem processes. In this endeavor we mainly focus on ammonia oxidizing and denitrifying microbial communities. These communities serve as model systems to address fundamental questions in microbial ecology, such as the relationship between community composition and functioning or genetic disposition and environmental selection, as well as applied questions related to sustainable agriculture and other nitrogen related environmental issues like treatment of nitrogen polluted water.
Pollutant Degradation - John Stenström
The Swedish EPA estimate that there are 1 400 contaminated sites in Sweden that can pose a large risk for the environment or for human health. We study how microorganisms, especially actinobacteria and white-rot fungi, can be used to clean up such contaminated sites from organic contaminants.
We also study the environmental fate of pesticides and develop bioprophylactic methods and techniques to prevent pesticide contamination of the environment. A special topic has for a long time been studies of weed control and microbial degradation of herbicides in railway embankments where we have an on-going collaboration with the Swedish Traffic Administration.
Using bioprophylactic approaches we aim to prevent contamination, both from point sources (for example from spills occurring at the filling of the spray tank) and diffuse sources (for example from leaching and surface transport after spraying in the field). One efficient and simple method for reduction of point source contamination is the use of biobeds. For reduction of diffuse contamination we study the possibility to add pesticide-degrading microorganisms or enzymes concurrent with the pesticide application. We also study the possibility to reduce pesticide transport in the environment by using biochar as an adsorbent.
Recycling of Urban waste - Mikael Pell