Conservation AQA A2 Biology Unit 4 Populations and energy Conservation of: Wildlife Habitats Biodiversity What is Biodiversity? The Variety of Life in all it’s manifestations. Or: The variety of organisms at all levels: Genetic Species Populations Usually measured as species richness How do we conserve Biodiversity? Legislation - International Conventions - European Directives - UK Laws Habitat Management Legislation: The Rio Earth Summit, 1992, produced the International Convention on Biological Diversity. 152 Countries signed this, committing them by law to adopt ways and means of protecting biodiversity. European Response: EU Habitats Directive (1992) identifies habitats in need of special protection (Annex 1) priority species (Annex 2) Natura 2000 was also set up under the directive. Natura website This is a coherent network of protected sites containing the habitats and species listed in the directive. UK Legislation Habitat Regulations (1994) implement the EU Habitats Directive These list and protect species and habitats of european importance Browse SACs on a map Habitat Management The main aims of habitat management are: 1. To manage the process of ecological succession. 2. To maintain or increase biodiversity. Habitat Management Techniques Coppicing Grazing Mowing Scrub clearance Burning Coppicing This is a traditional form of woodland management. Trees are cut close to form stools from which new poles regenerate. This increases light levels and species diversity in the wood. Coppiced and Pollarded trees Grazing Grassland is best managed by grazing. This keeps grasses short allowing other plant species to compete successfully. Grazing also causes poaching providing bare earth for seed germination Mowing Used where it is not practical to graze a site. Mowing should take place 2-3 times a year, with the last cut as late as possible to let flowering species set seed. Cuttings should be removed from the site to prevent nutrient enrichment of the soil which would encourage grasses to grow. Scrub Clearance Scrub such as brambles, shrubs and young trees can be cut back manually. Some scrub cover is sometimes left for nesting birds and invertebrates such as butterflies. Burning This is a technique often used on heathlands as it encourages the regeneration of plants such as heather and gorse.