Defra - Department for Environment, Food and Rural Affairs.

Science Search

Science and Research Projects

Return to Science Search homepage   Return to Project List

Diversification of grassland through the manipulation of plant-soil interactions and the identification of indicators of restorability - BD1451

Description
A key requirement for the successful restoration of biological diversity in grassland is the enhancement of efficient nutrient recycling in soil and the development of important plant-microbial associations, such as mycorrhizal fungi, that influence plant community structure and nutrient supply. It was recently proposed that shifts in the composition of the soil microbial community, especially the relative abundance of bacteria to fungi (bacterial-to-fungal biomass ratio) measured using phospholipid fatty acid analysis (PLFA) might be a useful bio-indicator of these properties and of the suitability of a site for restoration management. The main objective of this study is to confirm this by testing across a wide range of grassland types in England the reported association of high fungal-to-bacterial ratios with species-rich grasslands relative to improved and semi-improved grasslands, and to use this information to evaluate the potential of these microbial, and other measures, as indicators in agri-environment schemes to target sites for re-creation, or enhancement, of botanical diversity. An additional aim of our study is to identify management options to promote soil fungal-to-bacterial biomass ratios with the aim of enhancing the rate of recovery of botanical diversity in restoration schemes. Based on our previous studies, we have designed a range of experiments that enable us to test how introductions of particular plant species into swards might enhance the growth of fungi, thereby creating soil conditions favourable for enhancement of plant diversity. To increase experimental rigour, we propose to conduct these experiments at three sites across the UK to determine how inherent variation in soil conditions and climate impact on these plant-soil relationships. In association with these experiments, we plan to use novel stable isotope approaches to identify the mechanisms underlying the influence of plant species on fungal-to-bacterial ratios and soil biota influences on vegetation development. Overall, the project will provide a database and knowledge that can be used to refine the identification of sites for restoration of botanical diversity, and also provide realistic management options, based on mechanistic understanding of plant-soil associations, for enhancing botanical diversity in grassland.
Objective
1. To confirm the reported association of high fungal to bacterial ratios with species-rich grasslands relative to improved and semi-improved grasslands.
2. To quantify the impact of key plant species in the development of fungal dominated soils and resultant impacts on vegetation community development.
3. To identify the mechanisms underlying the influence of plant species on fungal to bacterial ratios in the soil and soil biota influences on vegetation development.
4. To evaluate other potential indicators that could be used in agri-environment schemes to target sites for re-creation or enhancement of grassland.
Project Documents
• EVID4 - Final project report : DIGFOR FINAL REPORT   (9907k)
• SUP - Supplementary Report : DIGFOR Extension Final Report   (562k)
Time-Scale and Cost
From: 2004

To: 2012

Cost: £804,475
Contractor / Funded Organisations
University - Reading, University - Newcastle, University - Lancaster, North Wyke Research, Institute of Grassland and Environment Research (IGER)
Keywords
Environmental Protection