section_path: Flora and fauna/Impact of agriculture
section_name: Impact of agriculture
paragraph_text: Impact of agriculture
  
  The long history of agricultural production, coupled with modern intensive agricultural methods such as pesticide and fertiliser use and runoff from contaminants into streams, rivers and lakes, has placed pressure on biodiversity in Ireland. A land of green fields for crop cultivation and cattle rearing limits the space available for the establishment of native wild species. Hedgerows, however, traditionally used for maintaining and demarcating land boundaries, act as a refuge for native wild flora. This ecosystem stretches across the countryside and acts as a network of connections to preserve remnants of the ecosystem that once covered the island. Subsidies under the Common Agricultural Policy, which supported agricultural practices that preserved hedgerow environments, are undergoing reforms. The Common Agricultural Policy had in the past subsidised potentially destructive agricultural practices, for example by emphasising production without placing limits on indiscriminate use of fertilisers and pesticides; but reforms have gradually decoupled subsidies from production levels and introduced environmental and other requirements. 32% of Ireland's greenhouse gas emissions are correlated to agriculture. Forested areas typically consist of monoculture plantations of non-native species, which may result in habitats that are not suitable for supporting native species of invertebrates. Natural areas require fencing to prevent over-grazing by deer and sheep that roam over uncultivated areas. Grazing in this manner is one of the main factors preventing the natural regeneration of forests across many regions of the country.