1. Ecosystems
1.1. A unit which includes all biotic abiotic parts in an area
1.2. Food chain - what eats what
1.3. Food web - lots of food chains,
1.4. Decomposer - organism that gets energy by breaking down dead material
1.5. Inter dependant - depend on others, if one part changes it affects other parts.
1.6. Nutrients cycle
1.6.1. Dead material decomposed - nutrients into soil
1.6.2. Nutrients taken up from soil by plants
1.6.3. Plants may be eaten by consumers
1.6.4. Plant and consumers die - nutrients returned to soil
1.7. Producers - make their own food.
1.8. Consumers - feed on producers or other consumers to survive.
2. Adaptations of tropical rainforests
2.1. Plants
2.1.1. Tall trees competing for light - butress roots
2.1.2. Plants have thick waxy leaves with pointed tips (drip tips) - channel the water to run off
2.1.3. Smooth thin bark - water run off easily
2.1.4. Climbing plants use tree trunks to climb up to sunlight
2.2. Animals
2.2.1. Strong limbs to climb and leap
2.2.2. Some birds have short pointy wings so they can easily move between trees
2.2.3. Camouflage - hide from predators
2.2.4. Noctornal - sleep in day and awake at night which saves energy
3. Deforestation
3.1. Why rainforests are cut down?
3.1.1. Population pressure - pop increases
3.1.2. Mineral extraction - minerals mined to make money
3.1.3. Energy development
3.1.4. Commercial farming - trees felled to make money
3.1.5. Subsistence farming - forest is cleared so farmers can make food for themselves.
3.2. Environmental impacts
3.2.1. Rain washes away soil leading to flooding
3.2.2. Nutrients in soil washed away - no trees to intercept rainfall
3.2.3. More CO2 in atmosphere - add to greenhouse effect
3.3. Economic impacts
3.3.1. Creates jobs
3.3.2. Money is made from selling timber
3.3.3. Deforestation can destroy natural resources that countries depend on
4. Managament strategies - cold environments (sustainability)
4.1. Using technology - trans-Alaskan pipeline
4.1.1. Helps reduce environmental damage
4.1.1.1. Pipeline is raised and insulated to retain heat and prevent it melting the permafrost.Wildlife can travel underneath it
4.1.2. Advantages
4.1.2.1. Solution to arctic sea ice preventing tanker movement in Winter. Crosses 2 mountain ranges and 800 rivers and is 1500km long. Engineered to slide during earthquakes
4.1.3. Disadvantage
4.1.3.1. wildlife could be harmed if there is a leak.
4.2. International agreements - The Arctic treaty
4.2.1. Helps reduce environmental damage
4.2.1.1. Protects natural environment by recognising the importance of the continent for scientific research (climate change)
4.2.2. Advantages
4.2.2.1. Preventing economic development, promoting research and controlling tourism to keep disturbance at a minimum
4.2.3. Disadvantage
4.2.3.1. Only works if all relevant countries sign it.
4.3. Conservation groups
4.3.1. Helps reduce environmental damage
4.3.1.1. WWF provides scientific information to work with local communities to manage critical ecosystems
4.3.2. Advantages
4.3.2.1. Helps to protect important species, and plans a sustainable future for the Arctic.
4.3.3. Disadvantage
4.3.3.1. Not all of the money goes to the charity.
5. Global ecosystems
5.1. Tundra
5.1.1. High altitudes (Norther Europe, Alaska) - winters and very cold, summers are brief
5.2. Grassland
5.2.1. Savanna grasslands - between tropics (distinctly dry and wet seasons)
5.2.2. Temperate grasslands - found at higher latitudes (more variation in temperature, less rainfall)
5.3. Temperate deciduous forest
5.3.1. Mid latitudes - 4 distinct seasons, summers are warm, winters - mild
5.4. Polar
5.4.1. North and south polar - very cold, icy, dry not much grows
5.5. Hot desert
5.5.1. North and south of equator - very hot during day and cold at night
6. Tropical rainforests
6.1. Same climate all year round
6.2. Soil is not very fertile - heavy rain washes nutrients away.
6.3. Most trees are evergreen
6.4. Contain more animal species than any other ecosystem
6.5. Home to many people who lived there over many generations
6.6. Biodiversity - variety of organisms in a particular area (rainforests have a very high biodiversity)
7. Cold environments
7.1. Types
7.1.1. Polar
7.1.1.1. extremely cold throughout the year, covered in ice
7.1.1.2. Some plants - mosses and lichens are found on fringes of the ice.
7.1.1.3. Few animals can survive - polar bears have adapted to retain heat (thick fur, and an insulating layer of fat)
7.1.2. Tundra
7.1.2.1. Climate - less extreme
7.1.2.2. Some animals live here such as arctic fox - more food options.
7.1.2.3. Permafrost (soils are frozen), soils are infertile, water removes nutrients and soils become water logged - because water is trapped by permafrost.
7.1.2.4. Low growing flowering plants, warmer areas - low bushes and small trees.
7.2. Interdependance
7.2.1. Permafrost - melts for a few months in summer creating an "active layer" with ice underneath. The melting of permafrost allows plants to absorb water through roots to photosynthesise eg.
7.3. Adaptations to physical conditions
7.3.1. Thin and waxy leaves reduce water loss
7.3.2. Hairy stems keep plants warm
7.3.3. Low growing and cushion like to protect and insulate themselves from strong dry winds.
7.3.4. Flowering and seed formations happens in a short time so reproduction can happen in summer
7.4. Why do cold environments need to be protected
7.4.1. Many indigenous people live a traditional life there
7.4.2. Home to many birds, animals and plants
7.4.3. Unpolluted and unspoilt cold environments are important outdoor laboratories for scientific research.
7.4.4. Beauty and potential for nature activities attracts many tourists - Norway eg.
7.4.5. Provide opportunities for forestry & fishing