Biodiversity, Biogeography and Ecosystem Science Flashcards
(33 cards)
Define biodiversity
The study of biological diversity, and the processes that create and maintain it
Define biogeography
The study of the distribution of species and ecosystems in geographic space and through (geological) time
Define ecosystem science
The study of the inter-relationships among the living organisms, physical features. biochemical processes and human activity in ecological communities
Define abiotic
Abiotic factors are non living chemical and physical parts of the environment that effect living organisms and the functioning of ecosystems
Examples of abiotic factors
Sunlight
Temperature
Soil type
Nutrients
Define biotic
Living things that shape an ecosystem
Examples of biotic factors
Animals
Plants
Bacteria
Fungi
How did Ryan, 1992 define biodiversity?
The variety of life and its processes
How did the UN environment programme, 1991 define biodiversity?
The variety of and the variability among living organisms and the ecological complexes of which they are apart; this includes diversity within species, between species and of ecosystems
Ways of measuring and monitoring biodiversity
- Genetic diversity
- Species diversity
- Higer taxon diversity
- Indicator groups
- Surrogate environmental measures
Measures of richness and evenness
Simpsons diversity index D
- lower value of D = more diverse sample
Ni (Ni - 1) divided by N (N - 1) = D
- Ni = number of individuals of a given species
- N = total number of individuals in the sample
How to quantify biodiversity at different scales
Local - Alpha diversity
Regional - Gamma diversity
Different scales - Beta diversity
Alpha diversity
Local diversity in a single habitat - could be number, richness or evenness of species
Gamma diversity
Total regional diversity of a large area, landscape or region
Beta diversity
The measure of how different habitat diversity is within an area or along a gradient - links local and regional diversity
Define historical biogeography
Reconstructing the origin, dispersal and extinction of species or taxonomic groups
Define ecological biogeography
Present distributions and geographic variation in diversity, how biotic and abiotic interactions influence species distribution
How do species get to where it is?
2 main natural processes
- Dispersal - movement of individual
- Vicariance - Historical reasons
Why so species thrive where they are?
Concept of biomes = biological ‘meta communities’
- Collections of areas with similar abiotic factors
- Produce similar ecological communities
- Example - Rainforests
Biotic factors which impacts species distribution
- Influence of ecosystem engineers - humans, bears
- Interactions between species
- Individual response of species
Abiotic factors which impacts species distribution
- Geographic template
- Temporal dynamics of geographic template
- Plate tectonics, sea level change and climate change
Theories of biogeography
- Historical theory
- Equilibrium theory
- Intermediate disturbance theory
- Theory of island biogeography
Define anthromes
- Anthropogenic biomes
- Represent landscapes defined by
population density, land use, biota, climate and geology
What is an ecosystem?
A whole community of organisms
