Microbes and drought
Microbes are important for many soil processes that contribute to the production of food and fibre on which humans rely. Under climate change, there is likely to be an increase in the intensity and frequency of drought in New Zealand and despite microbes’ role in soil, little is known about how drought affects soil microbes. We therefore conducted a literature review to assess what we do and do not know about the effects of climate change-driven drought on soil microbial function and adaptation.
The project focussed on many areas including:
- How microbes respond to drought and how that affects carbon, nitrogen, and phosphorus cycling in soils
- The interaction between microbes and soil water repellency under drought
- How plant pathogens may behave under drought and impact on plant production
- How changes in microbes may affect plant production
- How microbial communities change in response to drought conditions
- What drought effects might differ between pastoral grazing, production forestry, and cropping
- How advanced genetic techniques could contribute to understanding the effects of drought on microbial community composition and the ability of microbes to cycle organic matter
- Possible mitigation strategies for drought
Main findings:
During drought:
- microbial function decreases
- microbial community structure is altered
- soil water repellency may worsen the effects of drought
- pathogen disease expression will vary
- nutrient cycling and plant production will decrease
While the main findings of the project were not affected by land use, there were some land use-specific outcomes, research areas, and mitigation strategies to be considered:
The persistence of drought effects will be affected by the duration, intensity, and timing of drought and the subsequent rewetting phase. Due to a lack of information applicable to New Zealand, we have identified several areas that require further investigation. A link to the completed report to MPI will be supplied on this webpage when available.
The project was funded from the Sustainable Land Management and Climate Change Research Programme (SLMACC 405211) by the Ministry of Primary Industries. The team was led by Suzanne Lambie (Manaaki Whenua – Landcare Research) and included Karin Müller (Plant & Food Research), Gavin Lear (University of Auckland), Steven Wakelin (Scion Research), Simeon Smaill (Scion Research), and Kate Orwin (Manaaki Whenua – Landcare Research). Manaaki Whenua – Landcare Research greatly appreciates the contribution of Knowledge Navigators (Plant & Food Research) to the literature review.