Agriculture and the Environment

Agriculture and the Environment

• Sources of Pollution in Farming
  Silage effluent
  Fertiliser run-off
  Silage/hay wrap
  Sheep dip
  Slurry
  Milk
  Dairy washings
  Pesticides, herbicides and fungicides
  Farmyard manure
• Pollution of Watercourses
  Organic pollutants are broken down by oxygen in water. Some substances are more pollutant than others.
  The pollutant value of a substance is given by its BOD value.
  BOD = Biochemical Oxygen Demand: the amount of dissolved oxygen needed to break down organic matter in a 1 litre sample of water.
• Pollution of Watercourses
  As pollutants enter watercourses the nutrients they contain can cause eutrophication.
  Eutrophication: The enrichment of a habitat or environment with nutrients.
  The nutrients in the water can lead to growth of algae known as algal bloom.
  When algae die, oxygen in the water is used by bacteria to decompose the remaining organic matter.
  This oxygen depletion means that other aquatic species such as fish cannot survive due to the lack of oxygen, and die.
  This is known as a fish kill.
• The Nitrates Directive
  As run-off from fertilisers can cause water pollution, there are restrictions on when and where fertilisers can be applied.
  Do not apply if
  –land is waterlogged
  –land is flooded
  –land is snow-covered or frozen
  –heavy rain is due
  –land is steeply sloped
• Biodiversity
  Biodiversity: All living organisms within an ecosystem; this includes plants, animals and micro-organisms.
  Biodiversity is enhanced by various schemes:
  –REPS
  –FEPS
  –Organic Farming Scheme
• Encouraging Biodiversity
  Flowers and grasses in traditional haymeadows produce seed, which benefits wildlife.
  Nature corridors and hedgerows are an important part of wildlife habitats.
  Minimise use of pesticides and herbicides.
  Plant both coniferous and deciduous species in forest plantations.
• Hedgerows
  Natural habitat for many species.
  Provide shelter to livestock.
  Food source to many mammals and insects.
  Form natural land boundaries.
  Improve growth of plants on sheltered side of hedgerow.
  Aesthetically pleasing.
• Rural Environment Protection Scheme (REPS)
  Some of the measures undertaken by farmers in REPS:
  –Protection and maintenance of watercourses
  –Retention of wildlife habitats
  –Maintenance of field boundaries
  –Cessation of the use of herbicides, pesticides and fertilisers around hedgerows and watercourses
  –Production of tillage crops without burning stubble
• Organic Farming
  Agricultural activity which does not rely on chemical fertilisers, pesticides, genetically modified crops or livestock antibiotics.
  Instead green manures are used and farm rotations implemented.
  Biological pest controls are implemented.
  Mechanical methods of cultivation are used to control pests and weeds.
• Advantages of Organic Farming
  Animals are free range and live in suitable conditions.
  Animals are reared on land free of chemicals.
  Crops are not genetically modified.
  Soil structure is protected by rotations.
  Waterways are not at risk of pollution.
  Habitats are maintained.