Living Things Flashcards
What is a biome?
A large scale ecosystem across the world where the climate, vegetation and soils are all broadly the same within the area.
What is biotic?
The living parts of an ecosystem.
What is abiotic?
The no living parts of an ecosystem
What is eco tone?
The gradual change from one ecosystem to another
Describe the nutrient cycle
- Weathered rock releases nutrients into the soil
- Water is added to the soil by rainfall
- Plants absorb nutrients through their roots and leaves
- Animals gain nutrients by eating plants
- Plants and animals die and are decomposed by bacteria and fungi
- Nutrients are returned to the soil
Describe the energy cycle
Plants produce energy by photosynthesis
Herbivores eat the plants, carnivores eat the herbivores. The energy is moved through the food chain
The number of organisms at each stage of the food chain decreases because energy is used up by the organism.
Describe the structure of the rainfores
- Emergent layer
- Canopy layer
- Shrub layer
- Forest floor
What are the 4 factors that affect the nature of a biome?
Climate
Air pressure
Prevailing wind
Altitude
How does climate affect the nature of a biome?
It is hotter closer to the equator than it is at the poles. This is because the Suns rays are more concentrated and direct at the equator as they travel a shorter distance. Near the poles, the Suns rays are more spread out. This means it is colder so there are biomes such as tundra
How does air pressure affect the nature of a biome?
Areas of high and low pressure are cause by descending and ascending air. As air warms, it ascends, leading to low pressure at the surface. Low pressure causes precipitation. Biomes such as tropical rainforests grow in areas of low pressure. As air cools it descends leading to high pressure at the surface. Clear sky areas are common so deserts may be found in areas of high pressure
How does prevailing winds affect the nature of a biome?
If the prevailing wind comes from the ocean, it will bring precipitation. If it comes from a continental area, it will bring dry conditions.
How does altitude affect the nature of a biome?
The higher you are the colder and wetter it gets. This is due to warm, moist air from the ocean rising and cooling. As it cools, clouds form and produce rain. Rain is seen on the windward slope.
CASE STUDY- how do people use ecosystems?
Tropical Rainforest
location- found in equatorial countries like Brazil- Amazon Rainforest
Over the last 100 years, 50% of tropical rainforest has been destroyed due to
cattle ranching, mining, logging, hydroelectricity, agriculture
Impacts- Jobs created, profits from mining ect go back to MEDCs without benefiting rainforest communities, prevents further discoveries of medicine, people lose their homes and way of life, fertile soils are washed away when rainforest is cleared, roads divide up rainforest and can cut off connections between different biotic and abiotic systems, Burning of forests adds to CO2
CASE STUDY- using ecosystems in a sustainable way s
Tropical rainforest
Ecotourism- a form of sustainable tourism
Afforestation- trees are replanted
Forest reserves- some areas of forest are protected from exploitation.
Monitoring- satellite technology used to check activities in forest are
legal
Education- educate MEDCs so they understand the principles behind their actions
Selective logging- only some trees are cut down
Describe mangroves and mangrove destruction
Mangroves are salt tolerant trees which grow is salt marshes. Found in tropical and sub tropical areas.
They are a natural sea defence against cyclones and flooding.
In the past 10 years 35% of mangroves have been destroyed due to deforestation and shrimp aquaculture.
This makes coastal areas more vulnerable to flooding.
