biodiversity within a community

biodiversity meaning?

• the term used to describe the variety in the living world

• it refers to the number and variety of living organisms in a particular area

what are the 3 components of biodiversity?

• species diversity

• genetic diversity

• ecosystem diversity

species diversity meaning?

• it refers to the number of different species and the number of individuals of each species within any one community

genetic diversity?

• it refers to the variety of genes possessed by the individuals that make up a population of a species

ecosystem diversity?

• the range of different habitats, from a small local habitat to the whole of the earth

what is a habitat?

• an area where an organism lives

what is species richness?

• the number of species in a habitat or community

• it can be measured by counting the number of different species in the habitat

how can biodiversity be measured?

• using index of diversity

  • index diversity uses the number of species (species richness) and the number of individuals in each species (species abundance)

equation of index diversity?

benefit of using this index?

• the benefit of using the index of diversity instead of just species richness is that it takes into account the population sizes of different species in one community

• the greater the value for index of diversity, the more diverse the community

impact of agriculture of biodiversity?

• deforestation

• pesticides

• herbicides

• monocultures

deforestation?

• large regions of forests are cleared to provide space for crop or livestock farms

• forests are biodiverse environments because there are many different habitats for different species

how does removal of forests decrease biodiversity?

• the direct removal of species (e.g- trees)

• the removal of habitats causing species to die

pesticides?

• pesticides are sprayed onto crops to prevent pests (e.g- slugs) from feeding on crops

• pesticides reduce biodiversity for 2 reasons:

  • direct removal of pests

  • species that feed on the pests cannot survive

herbicides?

• herbicides are sprayed onto crops to prevent growth of unwanted plants and weeds

• herbicides reduce biodiversity for 2 reasons:

  • the direct removal of plants

  • species that feed on the unwanted plants cannot survive

monocultures

• this is when only one type of organism (usually 1 crop species) is grown in a particular area

  • a monoculture directly decreases biodiversity

  • fewer species can survive in monoculture environments