The Biosphere Flashcards
Describe how climate can affect ecosystems.
Precipitation
- timing and intensity
Temperature
- Most plant species can only operate between 10˚C-35˚C
- Broadleaf evergreen, broadleaf deciduous, coniferous or boreal
Light
- Vital for photosynthesis and ultimately the ecosystem
Wind
- Movement of materials
- Reduce water availability by increased evaporation
- increase rate of transpiration
Define: biome.
A large ecosystem made up of specific vegetation types and associated fauna. Recur in similar climates. Affected by latitude.
Forest, savanna, desert, tundra.
Describe how topography can affect ecosystems.
The higher the altitude, the greater decrease in:
- soil depth
- air temperature
- number of plant species
- heigh of plants
- density of plants
- growth rate of plants
- length of growing season
- increase in wind velocity and exposure
Slope
- affects stability of soil surface
- mass movement of materials
- accumulation
Aspect
- sunlight availability
Describe how soil can affect ecosystems.
- significantly affects vegetation and ultimately the rest of the ecosystem
- lateritic soils - tropical rain forests
- desert soils - desert and temperate grassland
- podzolic soils - temperate forests, coniferous and boreal
Describe how biotic factors can affect ecosystems.
- relationship results between plants and animals
- biome - complex interactive community
- includes human activity
Competition
- organisms compete for resources; the best survive
Symbiosis
- relationships can be beneficial or detrimental
- most plants rely on animals for pollination or protection
Define: biodiversity.
The variety of life, their genes and the ecosystem they are a part of.
Define: genetic diversity.
Inherited variation that occurs within a population of a species as a result of different genes or biochemical combinations e.g. pests and pesticides.
Define: species diversity.
Refers to the number of different species. The greater the range, the more resources and products are available.
Define: ecosystem diversity.
Refers to the number of different types of habitats, communities and ecological processes in the biosphere.
List the different levels in biotic indentification.
- Organism - individual
- Population - a group of individuals of the same species
- Community - all of the populations within an area
- Ecosystem - a community or species and their non-living environment
- Biosphere - the sum of all the earth’s ecosystems
How have the local vegetation been affected by topography, geology, animals and fire?
Topography
- altitude
- aspect
- soil accumulation sites
Geology
- parent material forms the soil, which, in turn, provide support for plants
Animals
- interactions with vegetation patterns
- dispersal of seeds and pollen
Fire
- regeneration
- mainly human intervention
Define succession and its terminology.
Succession is the natural change in structure and species composition of a plant community. Succession leads to the formation of complex communities of organisms possible in an area.
A sere is the name given to each stage in a sequence of events in which the vegetation develop over time.
A prisere is a complete chain of successive series. This encompasses the entire succession timeline - from pioneer to climax.
The first plants to colonise an area are the pioneer community.
The climax community is the final end product of succession, it is stable, but not permanent.
Define the two types of succession.
Primary succession
- the development of complex plant communities that may begin on bare, uncolonised ground that has never had any vegetation grown on it before.
- Can form on sand dunes, lava flows, landslides and glacial debris
Secondary succession
- When a community is removed or destroyed by human activities or natural events.
- When a climax community becomes modified or displaced, a disclimax or plagioclimax is formed.
