Living world

Question 1

Define an ecosystem

Answer 1

An ecosystem is a community of plants and animals that interact with the one another and their physical environment.

Question 2

What sizes are ecosystem

Answer 2

Local - a pond or under a dead log
Regional
Global - tropical rainforest. Also called biomes

Question 3

What happens at each level of the food chain the number of individuals ____________.
Why?

Answer 3

Declines
This is because not all individuals in any trophic level are consumed (eaten). This means not all energy is passed up to the next trophic level.

Question 4

Name a small scale ecosystem

Answer 4

A freshwater pond

Question 5

Pond producers:

Answer 5

Turn sunlight into energy
Plants- marsh marigold, water lily

Question 6

Pond consumers:

Answer 6

Water boatmen, Great diving beetle, small fish (stickleback), Frogs, Heron, Dragonfly, Kingfishers

Question 7

What is soil?

Answer 7

Soil is the top layer of the earth that is composed of disintegrated rock particles, humus, water and air.

Question 8

What is litter?

Answer 8

Litter is organic matter in and on the soil, it includes humus and leaf litter.

Question 9

What is biomass?

Answer 9

Biomass is the total mass of living organisms, mainly plant tissue, per unit area. It is a store of energy and is also known as standing crop.

Question 10

What is the nutrient cycle?

Answer 10

A nutrient cycle is the movement and exchange of inorganic and organic matter back into the production of matter.

Question 11

Where does nutrient cycling happen rapidly?
Why?

Answer 11

Tropical rainforests
Hot and wet

Question 12

Impacts of components of an ecosystem
Example

Answer 12

If any component within an ecosystem is changed it will have a knock on effect on the rest of the ecosystem.
Yellowstone National Park in the USA, reintroduced wolves in 1995.
16 packs of grey wolves introduced. Each pack kills one elk a day. More kills by wolves = more food for scavengers Reduction in predation from coyotes leads to increase in mice and voles
Elk population falls from 20,000 to 10,000 in 8 years.
Reduction in grazing pressure.
Aspen and cottonwood regenerate. There is more tree cover. Increase in bank side trees stabilises river banks so there is less erosion. More woody debris in rivers creates pools and trout habitats
Competition from wolves results in decrease in coyote population.
Reduction in grazing pressure. Aspen and cottonwood regenerate. There is more tree cover.

Question 13

Tropical rainforests occur..

Answer 13

..Along the equator
Constant 25-30°C
250mm rain per month

Question 14

Deserts occur..

Answer 14

..15-30°
Over 30°C
Less than 300mm per year

Question 15

Deciduous forests occur..

Answer 15

..30-60°N
500-1500 rain per year

Question 16

Coniferous forests occur..

Answer 16

..60°N
Cone bearing evergreen trees

Question 17

The Tundra occurs..

Answer 17

..Above 60°N ( arctic circle)
Less than 10°C
Less than 500mm rain per year

Question 18

Tropical rainforest characteristics:

Answer 18

Temperatures are high all year (around 28°C). Rainfall is around 250mm per month.

High levels of solar insolation means it is warm (26° C) . Air rises and causes clouds and rain (over 200 mm). These are ideal growing conditions for plants. No seasons so plants grow all year People have fully not disturbed these areas yet.

Question 19

What are the 5 layers of the tropical rainforest?

Answer 19

Question 20

Animal adaptations (TRF)

Answer 20

THREE TOED SLOTH - Powerful hooked claws to hang from trees. Fur green from algae giving it good camouflage in trees. Lives in trees (includes mating and giving birth to avoid predators).
RHINO BEETLE - Long horn at the front to fight and protect against predators. Curved black back to camouflage against forest floor.

Question 21

Plant adaptations (TRF)

Answer 21

Plants on the forest floor are shade tolerant and able to cope in the darker conditions.
Epiphytes grow high up on the branches of trees to gain access to the light.
Lianas wrap themselves around other trees to gain access to light.
Competition for light causes trees to grow fast. straight. BUTTRESS ROOTS support these tall trees.
DRIP TIP LEAVES that shed water quickly so they don’t snap under the weight of water

Question 22

What is biodiversity?

Answer 22

The variety of plant and animal life in the world in a particular habitat, a high level of which is usually considered to be important and desirable Diversity is higher in the tropics (not just tropical rainforests) primarily because there are fewer ecological obstacles to higher biodiversity.
In the tropics, plants and animals have the greate access to consistent energy, water, and carbon, et Until recently they have largely been undisturbed by natural or human processes.

Question 23

What are biodiversity issues in TRFs?

Answer 23

Deforestation
-individual plant species become extinct
-loss of possible cures for diseases
-biodiversity is reduced

Specific data:
137 plant and animal species are lost every single day due to deforestation.
By 2030, the Amazon Rainforest could lose 30-45% of their main species.

Question 24

Causes of deforestation

Answer 24

Malaysia

Commercial Farming Largest exporter of palm oil in the world. 1970s wide scale clearing of land.
Landowners given tax incentives to produce p. oil Logging 1980s Malaysia became world’s largest exporter of tropical hardwood. Selective logging more recent development
Mineral extraction Rainforest cleared on Peninsula Malaysia (tin and smelting). Drilling for oil and gas has started in Borneo.
Subsistence farming Tribal people practise subsistence farming, traditionally small scale and sustainable. Slash and burn is sust. but can grow out of control.

Question 25

Impacts of deforestation in malaysia

Answer 25

Economic gains and losses. Brings in jobs and income. Infrastructure opens up new areas for industrial development Palm oil/rubber provide raw materials for industry Destroys resources in the long term. Pollution of water courses Changes in climate Soil erosion Land left unprotected from heavy rain leads to landslides and flooding. Nutrients are washed away decreasing nutrients in the soil. Rivers silt up. Contribution to climate change Trees cut down change the water cycle and make it drier. Rainforests are the lungs of the earth and Hahon deforested there is more carbon dioxide in the air

Question 26

Sustainable management of TRFs

Answer 26

Sustainable Management of TRFs Selective logging. Only fell fully grown trees. Mark sustainable trees for sale. Conservation & education. WWF (NGO) educate and train conservation workers. Buy threatened areas. Ecotourism. Minimises damage to the environment and benefits locals - uses local material International agreements. International Tropical Trade Agreement restricts trade in hard woods. Debt reduction Donor countries and organisations have reduced debts in return for agreements that rainforest will not be deforested.

Question 27

Why are tropical rainforests important??

Answer 27

-50% of the world’s species -25% of all medicines -200+ plants have anti cancer properties -store carbon dioxide

Question 28

Characteristics of the polar biome:

Answer 28

Characteristics of a cold environment: Polar The Polar biome is the regions of the planet covered by ice most of the year. This includes large portions of the Arctic and Antarctic. Climate Winter temperatures often below -50 °C. Low precipitation levels Soils are permanently covered by ice during and permanently frozen Plants - mosses and lichens found on fringes Animals - Polar bears well adapted. Fur, fat, black nose and footpads

Question 29

Characteristics of the tundra biome:

Answer 29

Tundra Tundra is one of the coldest of all the biomes. treeless plain. It is noted for its barren landscapes, extremely low temperatures, little precipitation, poor nutrients, and short growing seasons. ... Permafrost soils Climate Less extreme - winter temperature may drop to -20C. Summers brief. Precipitation mainly snow Plants - Bearberry - low flowering. Low bushes/small trees

Question 30

Characteristics of the tundra biome:

Answer 30

Tundra Tundra is one of the coldest of all the biomes. treeless plain. It is noted for its barren landscapes, extremely low temperatures, little precipitation, poor nutrients, and short growing seasons. ... Permafrost soils Climate Less extreme - winter temperature may drop to -20C. Summers brief. Precipitation mainly snow Plants - Bearberry - low flowering. Low bushes/small trees

Question 31

Plant and animal adaptations (polar)

Answer 31

Lichens and moss have shallow roots. Lichens can even extract minerals from and grow on rocks. They can tolerate wet and dry conditions Shrubs eg the bear berry are low growing (20 cm) to cope with strong winds. Thick barked stems. Flower and seed formation short time in short summer. Hairy stems - keep plants warm Thin and waxy leaves - reduce water loss Bright red berries eaten and distributed Polar bear have white fur for camouflage, large padded paws to spread the weight on the ice Snowshoe hare will shed it white coat during the summer All animals have large blubber/ fat reserves to allow it to service for long periods without food.

Question 32

What is the albedo effect??

Answer 32

Ice reflects 90% of light back into space which keeps the planet cool

Question 33

Importance of cold environments:

Answer 33

Svalbard seed and feed bank This stores all the seeds and genes from every species in a giant natural fridge in the mountain should an extinction event occur. We have the ability to bring them back. Carbon and Methane store: The permafrost stores large amounts of these gas Habitat and home to many unique species and indigenous communities These places are wilderness areas that have remained undisturbed by humans meaning that unique species have lived and survived and there is wide "gene pool"

Question 34

Svalbard opportunities:

Answer 34

-rich fishing grounds 150 species of fish -mineral extraction (controversial - environmental) -geothermal energy close to Mid-Atlantic ridge, constructive plate margin, hot rocks

Question 35

Svalbard challenges:

Answer 35

Extreme Temperatures Longyearbyen - temperatures in winter -30C. Dangerous - risk of frostbite. Work slow and difficult due to heavy clothing Inaccessibility - Islands in a remote part of Europe. Only reached by road or ship. No roads in outlying communities. Snowmobiles in winter Construction-building houses, shops offices, maintaining roads and mining operations takes place in short summer months. Frozen ground provide solid foundations - although melting of permafrost Services - Water, electricity and sanitation. Kept off the ground to prevent permafrost thaw and easy maintenance

Question 36

Why and how to protect cold environments

Answer 36

Why protect cold environments? Indigenous people (eg. Inuit in Alaska) depend on wildlife for hunting Home to many birds, animals and plants Unpolluted regions are important for scientific research on climate change Beauty attracts tourists Opportunities for forestry and fishing Protect: Using technology - Trans-Alaskan Pipeline. Pipeline raised and insulated to avoid breaking in permafrost. Pipeline can slide in an earthquake therefore stopping leaks. Pipeline raised to allow caribou to migrate. Conservation groups - WWF in Canada. Provides scientific information and resources. Works with local communities Alaska USA - Companies must protect the environment and recognise rights of native people. Western Arctic Reserve - 9 million hectares of protected area.

Question 37

Abiotic-

Answer 37

Relating to non-living things

Question 38

Biotic-

Answer 38

Relating to living things

Question 39

What is a food chain?

Answer 39

A food chain is a linear network of links in a food web,

Question 40

What is a food web?

Answer 40

a complex network of interconnecting and overlapping food chains showing feeding relationships within a community