Theme 5c - Ecosystems Flashcards
What is an ecosystem?
The links between plants, animals and non-living things around them such as rocks, soil, water and climate.
What determines the ecosystem of an area?
- Rainfall
- Temperature
What is a tropical rainforest?
Located either side of the equator where hot and wet conditions encourage continuous growth of plants.
What is a temperate deciduous forest?
A hot and cold season means that trees lose their leaves in the winter to conserve energy.
What is a coniferous forest?
It is so cold in the winter that trees have evolved needle-like leaves to survive the frosts and reduce moisture loss.
What is the living called in an ecosystem?
Biotic
What is the non-living called in an ecosystem?
Abiotic
What are the factors effecting succession?
- Pioneer species
- Change in environment
- Soils becoming deeper due to weathering.
- Dominant species over running areas.
What is the water cycle?
Moves from land to the sky and then back again. It follows the cycle of evaporation, condensation and precipitation.
What is the nutrient cycle?
- Weathered rock releases nutrients into the soil
- Water is added to the soil by rainfall
- Plants absorb nutrients through roots and leaves
- Herbivores gain nutrients by eating plants
- Plants and animals die and are decomposed by bacteria and fungi
- Nutrients are returned to the soil
Explain food webs.
- The sun provided heat and energy
- Plants convert energy by photosynthesis
- Herbivores eat the plants
- Carnivores eat the herbivores (thus energy moving up the food chain)
- Food chains are connected to make a food web
- number at organisms at each stage decreases, along with the energy.
What is an endemic species?
A species which is only found in a given region or location and nowhere else in the world.
What is an indigenous species?
Originating in a particular area, region or nation; usually applied to flora, fauna and people.
What key services do ecosystems provide?
- Provisioning services
- Regulating services
- Cultural services
- Supporting services
Examples of key services provided by different ecosystems?
Coniferous forests - source of timber.
Savannah - provides materials for nomadic people
Peat bogs - huge stores of co2
Sand dunes - natural coastline defenses
What is an embryo dune?
The youngest of the dune at the front of the dunes, nearest the sea.
What is a fore dune?
Older and slightly higher dunes just shorewards of embryo dunes.
What are fixed or grey dunes?
Found further inland where conditions for plant growth improve.
What types of interference do humans have on sand dunes?
- Recreation
- Economic
- Environmental
- Management
What is a plagioclimax?
The plant community that exists when human actions prevent the climax vegetation being reached.
What is monoculture?
The cultivation of a single crop in a given area.
What is the multiplier effect?
The snowballing of economic activity, for example new jobs are crated, people who take them have money to spend in shops, which means that more shop workers are needed.
What is the Sahel?
A region in north central Africa south of the Sahara desert in an area prone to draught.
What is desertification?
The spread of desert, or desert conditions, from an established desert area into the surrounding area.
What is gully erosion?
Channels formed on a poorly vegetated hillside by soil erosion.
What is a fallow?
A field left to naturally regain its nutrients after growing crops for a number of years.
What are three major kinds of habitat loss?
Habitat destruction (eg deforestation) Habitat fragmentation (eg urban developments or dams) Habitat degradation (eg pollution)
What is genetic modification?
The placing of a gene from one organism into another so that the latter can take on a quality of the former that it doesn’t otherwise have.
What is agro-forestry?
A land-use management system in which trees or shrubs are grown around or among crops or pastureland.
