Award details

Mechanisms promoting stability and ecological sustainability of mixed swards

Reference	BBS/E/G/00003113
Principal Investigator / Supervisor	Dr Mervyn Owen Humphreys
Co-Investigators / Co-Supervisors
Institution	Inst of Grassland and Environmental Res
Department	Inst of Grassland and Environmental Res Department
Funding type	Research
Value (£)	444,223
Status	Completed
Type	Institute Project
Start date	01/04/1999
End date	31/03/2003
Duration	48 months

Abstract

We aim to understand the ecological mechanisms controlling stability and sustainability of mixed swards. This underpins two strategic objectives: 1. To develop new breeding objectives and management systems in order to control biodiversity in sustainable, profitable pastures and extensive grassland systems. 2. To develop new management systems for grasslands with improved value for landscape, amenity, conservation and environment. We focus on two levels of mixture: (a) the two-species ryegrass-white clover mixture that is most important for UK pastures and which provides a simple model for mechanistic studies applicable to more diverse systems; (b) mixtures of genotypes of white clover. In particular we will focus on the role of microenvironmental heterogeneity, the differential responses of plant species and genotypes to that heterogeneity and their contribution to generating it. The project has eight main aims: 1. Test the Turkington-Harper-Schwinning-Parsons hypothesis that small-scale cycles in the relative abundance of ryegrass and white clover are driven primarily by their differential interaction with nitrogen. 2. Improve spatially explicit mathematical models of grass-clover dynamics. 3. Assess the potential to manipulate the amplitude and spatio-temporal scale of the cycles by manipulating the nitrogen responses of white clover. 4. Develop improved methodologies for assessing the competitive balance between ryegrass and white clover. 5. Use AFLP for the routine fingerprinting of white clover clones and determine genetic structure in populations. 6. Complete assessments of genetic variation in cold tolerance. 7. Assess genetic variation in ability of white clover to compete with ryegrass. 8. Test the prediction of Sisyphean fitness that clone size is positively correlated with tolerance to recent local stresses, but not correlated tolerance to other stresses.

Summary

unavailable

Committee	Closed Committee - Agri-food (AF)
Research Topics	X – not assigned to a current Research Topic
Research Priority	X – Research Priority information not available
Research Initiative	X - not in an Initiative
Funding Scheme	X – not Funded via a specific Funding Scheme

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