Flashcards
Biodiversity
Flashcards do conjunto (28)
- 1BiodiversityRelates to a range of habitats from a small (local) habitat to the Earth
- 2HabitatA place where organisms live
- 3Species RichnessA measure of the number of different species in a community
- 4CommunityAll the different species living in a habitat
- 5What is Random Sampling?A method of collecting data on species richness
- 6Why is it "Random"?To reduce any bias
- 7How does it remove bias?Reduces the amount of human involvement in the process
- 8What is the first step in a method of random sampling?Divide the area the samples are taken from by placing 2 large tape measures at right angles at 1 corner (like an axis)
- 9Step 2Use a random number generator to select a coordinate for how far you will go along the X tape and another for the Y coordinate
- 10Why is a random number generator used?Prevent bias
- 11Step 3Place the corner of the quadrat at the point where the 2 coordinates intersect
- 12How is this quadrat used? (Step 4)COUNT THE NUMBER OF EACH SPECIES PRESENT WITHIN IT
- 13How can the effect of chance be reduced?Use a large sample size
Use statistics to analyse the data - 14How does increasing the sample size decrease the effect of chance?More data collected means a larger probability the sample reflects the true population.
Increases the RELIABILITY of the mean - 15What is the ideal sample size?10%
- 16How does data analysis with statistics reduce effect of chance?Determine to what extent chance had on results
- 17What are methods of statistical analysis?Calculate a standard deviation
T-test
Correlation coefficient
Chi-squared - 18Index of diversityA relationship between the number of species in a community and the number of individuals in each species
- 19How is index of diversity calculated?
- 20What is D?Index of Diversity
- 21What is N?Total number of organisms of ALL species
- 22What is n?Total number of organisms of each species/
- 23How does agriculture or deforestation impact on species diversity?Species richness is reduced e.g. monocrop
Use of techniques e.g. herbicides to kill weeds/ ploughing
LESS VARIETY OF FOOD SOURCES
FEWER HABITATS AND NICHES - 24How could a farmer increase diversity or species richness through conservation?Grow a variety of crops
Plant hedges around fields
MORE VARIETY OF FOOD SOURCES
MORE HABITATS AND NICHES - 25Why is it more useful to calculate index if diversity than just number of species?Index of diversity measures number of species and number of individuals within each species
Some species are only found in small numbers - 26Suggest a explanation for relationship between the idea of diversity for an animal (birds) and structural diversity for plants?More structural diversity in plants provides more variety of food sources and more habitats and niches
Birds feed/ nest at different heights
(Aka link specifically to the animal) - 27What is shown by a higher index of diversity?There are more different alleles therefore higher stability so more likely to survive environmental change
- 28Why is index diversity better than just the number of species present?This measures both the number of species and individuals within the species
Some species may only be found in small numbers
Informações
- Descrição
- Biology AS (Topic Flashcards) FlashCards sobre Biodiversity, criado por Alice Hathaway em 25-04-2017.
- Criado por
- Alice Hathaway · abr 2017
- Atualizado
- 4 mai 2017
- Visualizações
- 15
- Avaliação