What happens in the soil can have a huge impact on ecosystems and ecosystem services, such as plant biodiversity, agricultural pests and invasive species. Soil communities consists of a vast number of different organisms; bacteria, fungi, nematodes, worms and insects and many more. My work focuses mainly on arbuscular mycorrhizal fungi and nematodes.
Nematodes, also called roundworms, are found in a lot of different environments; sea and fresh water and in soil from the tropics to the polar regions, some of these even lead a parasitic lifestyle. Nematodes are easily affected by changes in the soil, especially due to agricultural practices such as cultivation and addition of fertilizers and pesticides. This makes them great indicators of disturbances in the soil.
Arbuscular mycorrhizal (AM) fungi are a very important symbiosis between fungi and plant roots, and this symbiosis is found in more than 80% of all plants living today. AM fungi provide the plants with a lot of benefits; the main one is providing the plant with nutrients in exchange for sugar, but they have also been shown to protect the plant against drought, herbivores and pathogens. Therefore, it is not an understatement to say that AM fungi are critical to plant performance.
Very little is known about how human mediated effects on the climate, such as changes in temperature, nutrient enrichment, drought etc. affect AM fungi and nematodes, and even more importantly, how changes in these organisms can affect the performance of above ground organisms and interactions. This is exactly what I am investigating.
In one of my projects I am studying the dispersal limitations of AM fungi and nematodes in a greenhouse setting. How the organisms are affected by dispersal limitation can tell us how they will react to habitat fragmentation under natural conditions. This ties together with another project I am currently working on, where I look at the diversity of AM fungi and nematodes across the Åland Islands at populations at different distances from each other.
Hopefully, at the end of my research we will know more about how climate change affects the soil community, and how that in turn affects ecosystem functioning.
Pil Uthaug Rasmussen
The writer is working as a researcher in Department of Ecology, Environment and Plant Sciences, University of Stockholm. Her PhD project “The impact of habitat fragmentation and environmental change on the soil community and its consequences for ecosystem services ” is funded by Nessling Foundation.