The Living World - Physical

Question 1

What is an ecosystem?

Answer 1

a natural system made up of plants, animals and the environment. there are often complex interrelationships between the living and non living components of an ecosystem.

Question 2

what is a producer?

Answer 2

convert energy from the environment (sunlight) into (sugars); they’re usually plants.

Question 3

what is a consumer?

Answer 3

they get energy from the sugars produced by the producers

Question 4

what are decomposers?

Answer 4

they break down plant and animals material and return the nutrients to the soil

Question 5

what is a food chain?

Answer 5

shows the direct links between producers and consumers

Question 6

what is a food web?

Answer 6

shows all the connections between producers and consumers in a more complex way

Question 7

what is nutrient cycling?

Answer 7

when plants or animals die, the decomposers help to recycle the nutrients making them available once again for the growth of plants or animals

Question 8

what does a freshwater pond provide?

Answer 8

a variety of habitats for plants and animals

Question 9

what are the components of a freshwater pond?

Answer 9

1 - pond margin = plenty of O2 and light here, shelter for the plants and insects for animals to eat
2 - pond surface = plenty of O2 and light here, animals breathe through their lungs, gills or skin
3 - above the pond surface = birds and animals breathe O2, food is found in or on the water or in the margins
4 - mid water = animals breathe through gills or skin, fish are the main predators and food is found on the surface or in the pool
5 - pond bottom = little )2 or light. plenty of shelter (rotting plants and stones) and food. decomposers and scavengers live here

Question 10

what are some of the pond species and their energy sources?

Answer 10

1. algae - sunlight
2. frog tadpole -microscopic plants, algae and midge larvae
3. sticklebacks - tadpoles, young fish and water flees
4. perch - small fish eg beetles
5. heron - fish, frogs, or larger fish

Question 11

what are the two types of causes that can change an ecosystem?

Answer 11

1) global changes eg climate change

2) local scale changes eg changes to a habitat ie when a hedge is removed

Question 12

what are the natural changes to an ecosystem?

Answer 12

rapid changes can have serious impacts eg extreme weather events can ne devastating to ponds and lakes. they could dry up in places, which changes the edge of pond environments. plants will dry out and die, fish could be starved of oxygen and not survive

Question 13

what type of human activities affect ecosystems?

Answer 13

1) agricultural fertilisers can lead to eutrophication’s where nitrates increase growth of algae, which will deplete oxygen and fish may die
2) ponds may be drained to use for farming. aquatic plants will die, as will dish and other pond life
3) wood cut down, destroying habitats for fish and affecting the nutrient cycle

Question 14

what are the changes in a pond ecosystem?

Answer 14

1) . the perch will eat more of the smaller fish and small animals like frogs
2) . this will reduce the amount of food for creatures further up the food chain eg heroin
3) . with fewer frogs, there will be an increase, of creatures below frogs in the food chain like slugs

Question 15

what are global ecosystems?

Answer 15

they are large ecosystems also known as biomes. they are defined by the dominant type of vegetation that grows in the region eg tropical rainforests or tundra

Question 16

what do global ecosystems form?

Answer 16

broad belts across the world from west to east, this is because the climate and characteristics are determined by global atmospheric circulation.

Question 17

what are the causes of variation in the west to east belts of vegetation?

Answer 17

ocean currents, winds and distribution of land and sea

Question 18

what are tropical rainforest ecosystems like?

Answer 18

• close to the equator
• they have temps and heavy rainfall associated with equatorial low pressure belt creates ideal conditions for plants to grow. they cover 6% of the Earth’s land surface

Question 19

what are deserts ecosystems like?

Answer 19

• roughly 30 degrees North and south of the equator
• they cover a fifths of the worlds land surface. hot deserts associated with the sub-tropical high pressure belts. sinking air stops clouds forming, resulting in high daytime temperatures, low night time temps and low rainfall

Question 20

what are polar ecosystems like?

Answer 20

• artic/Antarctic

- cold air sinks at the North and South poles, resulting in very low temperatures and dry conditions

Question 21

what are deciduous and coniferous ecosystems like?

Answer 21

• roughly 50-60 degrees N of the equator
• deciduous trees shed their leaves in winter to retain moisture. coniferous trees are cone-bearing evergreens, retaining their leaves to maximise PHS during summer months

Question 22

what are temperate grassland ecosystems like?

Answer 22

• roughly 30-40 degrees N and S of the equator

- experience warm, dry summers and cold winters

Question 23

what are Mediterranean ecosystems like?

Answer 23

• roughly 40-45 degrees N of the equator

- enjoy hot, sunny and dry summers with mild winters

Question 24

what are tropical grassland (savannah) ecosystems like?

Answer 24

• between 15-30 degrees N and S of the equator

- dry season can be very hot and wild fires can break out, thunderstorms can occur during the wet season

Question 25

what are tundra ecosystems like?

Answer 25

• arctic circle to 60-70 degrees N

- characterised by low growing plants adapted to retain heat and moisture in the cold, wind and dry conditions

Question 26

what is the climate like in tropical rainforests?

Answer 26

• temperature is high and constant all year round as the sun is overhead most of the time
• rainfall is high due to global atmospheric circulation, it causes and area of low pressure where rising air creates clouds and trigger heavy rainfall
• rainfall varies throughout the year, with the wet season lasting approx 6 months due to periods of heavy rainfall

Question 27

what are soils like in tropical rainforests?

Answer 27

heavy rainfall can quickly dissolve and carry away nutrients in a process called leaching, it leaves behind an infertile red, iron-rich soil called latosol

Question 28

what types of plants and animals are there in the rainforest?

Answer 28

• rainforests have a huge biodiversity
• birds live in the canopy and feed on nectar from flowers
• mammals eg monkeys and sloths are well adapted to living in the trees
• animals like deer and rodents live on the forest floor

Question 29

what are the adaptations of plants in the rainforest?

Answer 29

• the canopy is where there is most light, whereas the forest floor is dark and is were plants, animals, fungi and bacteria enjoy a very close relationship with the soils, temperature and moisture

Question 30

what is deforestation like in Malaysia?

Answer 30

it is a country in south east asia and 67% of Malaysia’s land is covered by rainforest
- the rate of deforestation in Malaysia is increasing faster than in any tropical country in the world

Question 31

how has logging caused deforestation?

Answer 31

recently, clear felling a method where all the trees where chopped down in area and has been replaced by selective logging where only full grown trees are cut down. trees that have important ecological value are left unharmed

Question 32

how has road building caused deforestation?

Answer 32

logging requires road construction to bring in machinery and take away the timber. roads are made to provide access to mining areas, new settlements and energy projects

Question 33

how has energy development caused deforestation?

Answer 33

the controversial Bakun Dam is Asia’s highest dam outside china, it supplies energy for industrial peninsular Malaysia, it has flooded over 700km cubed of forests and farmland

Question 34

how has mineral extraction caused deforestation?

Answer 34

rainforests had been cleared for mining and road construction, drilling for oil and gas has recently started on borneo

Question 35

how has commercial farming caused deforestation?

Answer 35

Malaysia is the largest exporter of palm oil, during the 1970’s, large areas of land were converted to palm oil plantations, which has increased due to plantation owners receive a 10 yr old incentive

Question 36

how has subsistence farming caused deforestation?

Answer 36

tribal people practise this and grow some food crops in cleared pockets of forest. ‘slash and burn’ is a method of clearing land, it involves the use of fire to clear the land, these fires can grow out of control, destroying large areas of forest

Question 37

how is soil an impact of deforestation?

Answer 37

removal of soil by wind and rain is soil erosion, the roots of trees and plants bind the soil together. so deforestation, means that soil can easily become loose and erode away

Question 38

how has deforestation contribute to climate change?

Answer 38

• trees give off moisture by the process of transpiration, deforestation reduces the moisture in the air resulting in a drier climate
• the process of evaporation uses up heat and cools the air, if trees are cut down, the cooling ceases and temperatures rise

Question 39

what are the economic gains of deforestation?

Answer 39

1. development of land mining, farming and energy will lead to jobs both directly (construction, farming) and indirectly (supply and support industries)
2. improved transport infrastructure opens up new areas for industrial development and tourism
3. hydro-electric power will provide cheap and plentiful energy

Question 40

what are the economic losses of deforestation?

Answer 40

1. pollution of water sources and an increasingly dry climate may result in water shortages
2. climate change could have economic costs as people have to adopt to live in a warmer world
3. fires can cause harmful pollution, they can burn out of control, destroying vast areas of valuable forest

Question 41

What are the rates of deforestation?

Answer 41

• every two seconds an area of rainforest the size of a football field is being destroyed
• the fastest rates of deforestation are in brazil and indonesia, but rates are decreasing in brazil and increasing in indonesia

Question 42

Why should tropical rainforests be protected?

Answer 42

1) . Biodiversity- they are home to 1000s of soecies
2) . Climate change - RF absorb and store CO2, helps reduce global warming
3) . Climate - 28% of rhe worlds oxygen comes from rainforests, they prevent the climate from becoming hot and dry
4) . Medicine - 25% of medicine comes from there, 2500 forest plants have anti cancer properties
5) . Resources- provide valubale hardwoods and nuts, fruit and rubber
6) . Water - 20% of fresh water comes from RF
7) . People - indigenous tribes live there and make use to resources without causing any long term harm

Question 43

why do rainforests need to be managed sustainably?

Answer 43

• to ensure that rainforests remain a lasting resource for future generations
• to allow valuable rainforest resources to be used without causing long term damage to the environment

Question 44

how does selective logging, conservation and education help make rainforests managed more sustainably?

Answer 44

1. selective logging - most damaging from of deforestation is clear felling, which destroys the ecosystem , so a more sustainable approach is selective logging
2. conservation & education - - rainforests can be a part of conservation areas eg national parks, they can be used for education, research and tourism. large companies invest in the areas in exchange for carrying out research

Question 45

how does ecotourism help make rainforests managed more sustainably?

Answer 45

it aims to introduce people to the natural world, to benefit local communities and the environment.
- through income generated by ecotourism, local people & governments benefit from retaining and benefitting their rainforest trees

Question 46

how do international agreements and hardwood forestry help make rainforests managed more sustainably?

Answer 46

1. international agreements - they’ve been made to help protect rainforests as they’ve now become a global importance
2. the forest stewardship council (FSC) is an international organisation that promotes sustainable forestry. it tries to educate manufacturers & consumers about the need to buy sustainable hardwood, it reduces the demand for rare ad valuable hardwoods.

Question 47

how do debt reductions help rainforests managed more sustainably?

Answer 47

• some countries have borrowed money to fund developments, to pay them off, some have raised money from deforestation programmes. some donor countries, have reduced debts in return for agreements that rainforests will not be deforested

Question 48

what are hot deserts like?

Answer 48

a desert is an area that receives less than 250mm of rainfall a year. they are mostly found in dry continental interiors, away from coasts, approx at 30 degrees N and S of the equator

Question 49

what is the climate like in hot deserts?

Answer 49

there is a persistant belt of high pressure, which explains the lack of cloud, and rain and the high daytime temperatures. however, with the lack of cloud cover temperatures can go to below freezing at night.

Question 50

how are plants adapted to live in the rainforest?

Answer 50

• small leaves, spines, glossy and waxy leaves which help reduce water loss
• seeds can stay dormant for years, but can germinate quickly when it rains
• some plants have horizontal root systems, just below the surface

Question 51

how are animals adapted to live in the rainforest?

Answer 51

• rodents are nocturnal and survive high temps by living in burrows underground and only venture out during cooler nights
• snakes and lizards retain water by having waterproof skin and making little urine
• camels are adapted to cope without water for many days

Question 52

what are soils like in the desert?

Answer 52

they tend to be sandy and stony, with little organic matter due to lack of leafy vegetation. they’re dry but can soak up water rapidly after rainfall

Question 53

what is the mineral extraction like as an opportunity for development in the Thar?

Answer 53

• the desert region has valuable reserves of minerals which are exported across the world. Gypsum is used in making plaster for the construction industry and Feldspar is used to make ceramics

Question 54

what is tourism like as an opportunity for development in the Thar?

Answer 54

• the Thar desert has many beautiful landscapes, in which desert safaris on camels based at Jaisalmer have become popular with many.
• an annual desert festival is held each winter, local benefit by providing food and accommodation or acting as guides

Question 55

what is energy like as an opportunity for development in the Thar?

Answer 55

1. coal - there are extensive lignite coal deposits in the Thar and a thermal energy supply has been built
2. solar - sunny, cloudless skies offers ideal conditions for solar power generation
3. oil - a large oilfield has been discovered which could transport economy

Question 56

what is farming like as an opportunity for development in the Thar?

Answer 56

• many people are involved in subsistence farming, they survive in hot & dry conditions by grazing animals on the grassy areas
• commercial farming has been made possible by irrigation, and pulses, sesame, maize and mustard are also grown

Question 57

What are the challenges of extreme temperatures?

Answer 57

1) . Working outside in the heat of the day can be very hard, especially for farmers
2) . High rates of evaporation lead to water shortages which affect people as well as plants and animals
3) . Plants and animals have to adapt to survive in the extreme heat, some are nocturnal and hibernate in the cooler ground during the day

Question 58

What are the challenges of watee supply?

Answer 58

• water is a scarce resource as population, industry and farming have developed; demand for water has increased. Also low rainfall, high temps and strong winds lead to high rates of evaporation
  1) . The few rivers ans streams there only flow after rainfall
  2) . Some water is obtained from aquifers, where its salty and not very good quality

Question 59

What are the challenges of accessibility?

Answer 59

• very limited road network across the That Desert, due to high temperatures it can cause tarmac to melt and the strong winds can blow sands over the road
• many places are accessible by camel, and public transport often involves seriously overladen buses

Question 60

what is desertification?

Answer 60

happens when land is gradually turned into a desert. most areas at risk are on the borders of existing deserts, eg Sahara desert in Africa; its a significant problem in the USA, Europe and Australia.

Question 61

how does climate change and fuelwood cause desertification?

Answer 61

• climate change = resulting in drier conditions and unreliable rainfall, it rains less than it did 50 yrs ago on average
• fuelwood = population growth has led to an increasing demand for fuelwood, trees are stripped of their branches and eventually die.

Question 62

how does population growth cause desertification?

Answer 62

• can result in land close to existing deserts being overgrazed. this means that there are too many animals to be supported by the limited vegetation; when the vegetation has been destroyed the land will turn to desert

Question 63

how does over cultivation cause desertification?

Answer 63

• resulted from the need to produce more food which led to the soil becoming exhausted. it will turn to dust and become infertile

Question 64

how does soil erosion cause desertification?

Answer 64

• its often linked to desertification. when vegetation has been destroyed the soil is exposed to the wood & the rain making it vulnerable to erosion

Question 65

what is the Indira Gandhi Canal like?

Answer 65

land is under irrigation- its the main form of irrigation in the desert (Rajasthan). it has.

1. provides drinking water for many people
2. commercial farming, growing crops eg wheat has now flourished in an area that used to be scrub desert
3. Jodhpur and Jaisalmer are two cities that have benefitted most, over 3500km (sq) of land is under irrigation

Question 66

what is water and soil management like in deserts?

Answer 66

• commercial farming in hot deserts often involves irrigation, however too much irrigation can cause problems leading to salinization. high rates of evaporation in hot deserts lead to a build up of salts on the surface, which reduces soil fertility and kills plants.

Question 67

what is water and soil management like in Australia?

Answer 67

• local farmers are encouraged to use the following methods to prevent soil erosion
  1. ponding banks - areas of land enclosed by low walls to store water
  2. contour traps - embankment built along the contours of slopes to prevent soil from being washed down during heavy rainfall.

Question 68

how does tree planting help soil desertification?

Answer 68

• its an important way of reducing erosion, the roots bind the soil together and the leaves and branches provide shade, grazing for animals and fuelwood.
• the Prosopis cineraria is well adapted to the hostile desert conditions, they also provide foliage and seed pods for animals to eat, good quality firewood and roots to stabilise sand dunes

Question 69

how does appropriate technology help soil desertification?

Answer 69

• many people living on the edges of deserts are poor so methods used involve materials that are appropriate to their level of development. they may have access to expensive machinery and sustainable approaches have to be practical and appropriate.

Question 70

what is the example of ‘Magic Stones’ as appropriate technology like?

Answer 70

• in rural parts of Burkina Faso lines of stones have been used to reduce erosion, they use basic tools and trucks to transport the stones and local people have built stone walls.