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A review of the potential effects of seed sowing for habitat re-creation on the conservation of infraspecific biodiversity - BD1447


One of the primary policy objectives of the Environmentally Sensitive Areas (ESA) and Countryside Stewardship (CS) schemes is to maintain and enhance biological diversity in the countryside. In order to achieve this many schemes recommend the introduction of wildflower species as seed mixtures. However, the widespread use of non-native genotypes in such restoration schemes has led to growing disquiet over the potentially deleterious impacts on the British flora. Although inconclusive, recent research suggests that genetic introgression between native and non-native/non-local genotypes could potentially occur in some situations. This may disrupt geographic patterns of genetic diversity, dilute native gene-pools, and reduce the fitness of subsequent generations. It has also been suggested that in some circumstances non-native genotypes may out-compete and displace local genotypes. This may cause significant disruption to the structure and function of ecological communities. Given government commitments to the conservation of biological biodiversity, a critical assessment of the likely effects of widespread introduction is therefore urgently needed.

Main objective
To critically assess the potential risks and/or benefits of the introduction of novel genotypes on existing local populations and semi-natural ecosystems.

Policy relevance
The conservation of genetic diversity is a key component of the UK Governments’ commitment to the conservation of biodiversity (Convention of Biological Diversity 1992, Article 2). A critical assessment of the positive and negative impacts of introduced genotypes will therefore be essential for the achievement of key policy objectives of the UK Biodiversity Action Plan (Anon. 1994) and Agri-environment schemes.

Intended use of results
The results of this project will inform best practice guidelines on many critical aspects of habitat restoration, namely (i) the sourcing and commercial production of wildflower seed, (ii) the selection of species and genotypes for restoration, (iii) the appropriate use of wildflower seed mixtures, and (iv) the design and location of restored habitats. In addition, the review will highlight gaps in the scientific knowledge, and help define and prioritise future research needs in this important area of ecology.


The aim of this project is to assess the risks and benefits of the introduction of novel genotypes on local populations of native species used in habitat re-creation. The specific objectives are:

1. Review published and unpublished information on the ecological attributes of species most commonly used in habitat re-creation (e.g. pollen transfer distances, reproductive mode and strategy);
2. Review published and unpublished research on the infraspecific variability of species used in habitat re-creation;
3. Assess the risk of inbreeding/outbreeding depression and/or loss of genetic variability within wild populations following the introduction of non-local genotypes;
4. Identify species or situations where the introduction of non-local genotypes would be beneficial, benign or detrimental to the conservation of genetic resources;
5. Identify gaps in knowledge and future research needs;
6. Inform guidelines on the selection, use and sourcing of wildflower species for the restoration of biodiversity.

Project Documents
• Final Report : A review of the potential effects of seed sowing for habitat re-creation on the conservation of infraspecific biodiversity   (1700k)
Time-Scale and Cost
From: 2003

To: 2003

Cost: £35,375
Contractor / Funded Organisations
Natural Environment Research Council
Environmental Protection              
Habitat conservation              
Nature conservation              
Fields of Study
Environmental Stewardship