Biodiversity Flashcards
What is species richness?
Is a measure of the number of different species in a community.
What is index of diversity?
Describes the relationship between the number of species in a community and the number of individuals in each species.
How does deforestation reduce biodiversity and increase yield?
Removal of trees to increase area for farmland to increase yield, which reduces the number and diversity of tree species, habitat and food sources.
How does hedgerow removal reduce biodiversity and increase yield?
Increase the area for farmland , which reduces number of plants and species, habitat and food sources. They are a source of pest, which eat crops and weeds, which compete with crops, which both reduce yield.
How do monocultures reduce biodiversity and increase yield?
Farmers plant fields containing only one species of plant, which means that fewer organisms can be supported and biodiversity is reduced.
How does filling in ponds and draining wetlands reduce biodiversity and increase yield?
Removes the habitat of aquatic species and could also be a source of food for other species, which means the organisms can no longer survive and therefore biodiversity is reduced.
How do pesticides reduce biodiversity and increase yield?
Sprayed on crops to kill insects, which would feed on the crops and reduce the yield. This directly reduces the number of insect species but also reduces the food source of organisms which feed on them, both reducing biodiversity.
How do herbicides reduce biodiversity and increase yield?
Sprayed on weeds, which could compete with crops. This directly reduces plant diversity and reduces food sources for some organisms.
How does effluent reduces biodiversity and increase crop yeild?
When it leaks into water it can lead to eutrophication and death of aquatic species. Use of fertilisers can also cause this as well.
Why are hedges more beneficial than building fences?
Increases plant species, which means more food sources and habitats, which increases biodiversity. They also increase the number of predators of pests, which means less crop damage and an increased yield.
