Agriculture

• Agricultural ecosystems are controlled by humans, and typically farmers will select species based on certain qualities that make the crops more productive. This reduces the number of species and the genetic diversity of the alleles they possess.
• Farmers must find a balance between the intense demand for food production and also conservation of habitats.
• The overriding effect of intensive food production is that the variety of habitats within ecosystems has been diminished, hence reducing species diversity.
• Certain practices have directly removed habitats and decreased species diversity. For example, removing hedgerows, creating monocultures, filling in ponds or draining marshland, and over-grazing of land by animals.
• Some practices have more indirectly impacted species diversity. For example, the use of pesticides/inorganic fertilisers, escape of effluent from silage stores and slurry tanks into water courses, and the absence of crop rotation or intercropping.
• Some conservation techniques have been implemented to find a compromise between food production and conservation of natural habitats. For example, using hedgerows instead of fences, intercropping, reducing the use of herbicides/pesticides, and preserving wetlands instead of draining these for agricultural use.
• Intercropping involves growing multiple different crops together in the same area, increasing species diversity.