On the Ecology of Saprotrophic Fungi and Bacteria in Soil: Biotic and Abiotic Control of Growth Rates
- Microbial Ecology
To summarise, a list of the main results of this thesis follows:
First, fungi and bacteria differed in their relative importance in the decomposition of different plant material in soil. Bacterial growth was more promoted by adding the plant material alfalfa (C:N = 15) compared with straw (C:N = 75).
Second, the turnover of fungi is slower than that of bacteria in soil, corroborating the suggestion of a slow and a fast energy channel, respectively, through the soil food web.
Third, the relative importance of fungi and bacteria is dramatically affected by soil pH – fungi more dominating at lower pH and bacteria at higher.
Fourth, the relative importance of fungi and bacteria is strongly influenced by the competitive interaction between the decomposer groups. This interaction could partly explain the relatively low fungal importance in high pH soils, but the fungal influence on the low bacterial growth in low pH soils could not be evaluated.
Fifth, this thesis demonstrates that the temperatures mediated by global climate change will affect the temperature response of microbial growth in a quantitative and predictable manner, making it possible to estimate the effect on microbial temperature sensitivity of future predicted temperature changes.
Growth rate measurements could reveal fungal and bacterial responses with high sensitivity, and greatly improved the resolution of effects on and due to fungi and bacteria. The techniques employed in this thesis therefore have the potential to become standard methods used to monitor environmental effects on the soil ecosystem both in the short-term (hours, for example following substrate additions) and the long-term (years, for example community adaptation to environmental factors). They should also be applied to study the energy flux through the basic trophic level of the soil food web, in investigating the effects of, and effects on, secondary consumers.
- Joshua Schimel (Professor)
- Biological Sciences
- decomposer ecology
- soil pH
- temperature relationship
- Fungal growth
- litter decomposition
- bacterial growth
- Microbial Ecology
- Erland Bååth
- ISBN: 978-91-7105-299-5
- Carbon drivers and microbial agents of soil respiration
- Effect of environmental factors on fungal and bacterial growth in soil
- Interaction between fungi and bacteria in soil
- Microbial carbon-use efficiency
Doctoral students and postdocs
PhD students, main supervisor
Visiting PhD students, main supervisor
PhD students, assistant supervisor
- Carlos Arellano
- Jian Li
- Jeppe Ågård Kristensen, Dept of Physical Geography and Ecosystems Science
- Bernice Hwang, Dept of Physical Geography and Ecosystems Science
- Aradhna Roberts, Dept of Physical Geography and Ecosystems Science