P1 SB The Living World 🌿 Flashcards
What are ecosystems?
Natural systems made up of plants, animals and the environment. Complex interrelationships between living + non-living components
Biotic = ?
Living factors eg plants / animals
Abiotic = ?
Non-living factors eg climate / soil
Large scale / global ecosystems are defined by what?
The dominating vegetation
KEY EXAMPLE: Avington Park lake. Where is it?
A country estate near Winchester, Hampshire
Avington Park lake is of ______ and _____ importance
Historical
Ecological
What was the issue at Avington Park lake?
Lack of maintenance = accumulation of silt + vegetation growth
What was a positive of what had happened at Avington Park lake?
It created excellent habitats for birds
What was a negative of what had happened at Avington Park lake?
The view of the lake from the house had been lost
When was the restoration carried out at Avington Park lake?
2014
What were the outcomes of the Avington Park lake restoration?
The view was restored, and new habitats were created to attract birds and water fowl
What is a producer?
An organism that converts energy from their environment into sugar
Eg plants
What is a primary consumer?
Something that gets its energy from producers
Eg herbivores
What is a secondary consumer?
Something that gets its energy by eating a primary consumer
Eg a carnivore
What do decomposers do?
Return nutrients to the soil
Eg bacteria / fungi
_____ one component of an ecosystem ____ all other ____
Changing
Impacts
Components
Example of changing a component:
If perch were added to a pond, they would eat more of the…
Smaller fish and animals such as frogs
The Mediterranean biome is found where?
40-45 degrees N of equator
Some other locations with similar climate, eg California, South Africa, western Australia
What are summer and winter like in the Mediterranean climate?
Hot, dry summers and mild winters
What kinds of plants can be found in Mediterranean climate?
Olive + fruit trees
Why is the polar climate so cold?
Cold air sinks at the north and south poles —> low temps and dry conditions
Where is temperate grassland found?
30-40 degrees N + S of equator
Eg prairies in N America, steppes in E Europe
Temperate grasslands are mainly used for what?
Grazing animals
Tropical rainforest is found…
Near the equator
Temperatures and rainfall are both high in what biome?
Tropical rainforest
What proportion of the world’s plant / animal species are found in TRFs?
Over half
What proportion of all medicines come from TRF plants?
One quarter
Desert biomes are found ___ degrees N and S of equator
30
Deserts cover what proportion of the world’s land surface?
One fifth
Hot deserts are associated with __-_____ high pressure belts
Sub-tropical
Tropical grassland (savanna) is found where?
15-30 degrees N and S
What large scale ecosystem is found 50-60 degrees N of equator?
Deciduous + coniferous forests
Why do deciduous trees shed their leaves?
To retain moisture
Why do coniferous trees keep their leaves?
To maximise photosynthesis in the summer months
Tundra is found ___ - ___ degrees north of the equator
60 - 70
In the tundra there are ___ growing plants adapted to retain ___ and ____
Low
Heat
Moisture
What is the climate like in TRFs?
Warm and wet
How much rainfall do TRFs receive each year?
Over 2000mm
What is the average temp in TRFs?
27 degrees C
Why is rainfall high in TRFs?
Due to low pressure over the equator
Rising air = clouds = heavy rain
How long is the wet season in TRFs?
6 months
The soil in TRFs is _____ and most nutrients are found…
Infertile
On the surface
Trees have ___ roots to absorb nutrients
Shallow
____ transfer nutrients directly from air (_____ _____)
Fungi
Nutrient cycling
Heavy ____ washes away nutrients, leaving behind ____, ___-rich soil
Rainfall
Infertile
Iron
Where do the majority of animals live in the TRF, and why?
In the canopy - most light
What adaptation do many leaves have that allows rain to run off?
A drip tip
Why to TRF trees have thin, smooth bark?
To allow water to flow down easily
Why do many leaves have flexible bases?
So they can turn to face the sun
What are epiphytes?
Plants that live on branches high in the canopy and get their nutrients from water and air rather than soil
What are lianas?
Woody creepers rooted to ground and carried into canopy by trees
What do buttress roots do?
Support base of tree, help transport water, may also help oxygen / carbon dioxide exchange by increasing surface area
How have sloths adapted to TRF conditions? Name 4 ways
Coat is camouflaged
Green algae grows on fur
Slow movements = concealed from predators who rely on vision
Sharp claws to grip branches and defend themselves
Turn head 270 degrees
Thick coats = dry during rainy season
Slow metabolism = stay in trees for days
How have strangler figs adapted?
Seed dropped in nook and uses debris as nourishment
Sends aerial roots down trunk
Gradually surrounds host
Branches grow taller to reach sunlight + roots rob host of nutrients
Host eventually dies and decomposes
A desert is…
An area that receives less than 250mm of rainfall / year
What are desert soils like?
Dry soil
Little or no organic matter due to lack of leafy vegetation
Evaporation draws salts to the surface leaving a white powder
Infertile
Hot deserts are found in ___ ____ ___ away from coasts
Dry continental interiors
Hot deserts are found in belts at approximately __ degrees N and S
These generally follow the lines of the Tropic of ___ and ____
30
Cancer
Capricorn
During what months are desert temperatures at their highest?
June to September
In winter there is some rainfall with around __mm per month
5
In winter temps drop by about __ degrees C
30
Around the tropics there is __ pressure due to the warm air ____
High
Sinking
How have cacti adapted to desert conditions?
No leaves so water loss is reduced
Store water in stems
Spikes to defend from being eaten by animals
How have animals adapted to desert conditions?
Fennec foxes have large ears to radiate heat away from their body, which cools them down
Camels store fat in humps instead of in their body so they don’t overheat
CASE STUDY: THAR DESERT
Where is the Thar?
NW India and into Pakistan
200,000 km squared
Most of it is in the Indian state of Rajasthan
The Thar is the most…
Densely populated desert in the world
In the Thar, soil and sand is…
And there is little…
Not fertile
Surface water
How much rainfall does the Thar desert receive each year?
Between 100mm and 240mm
What temperature does the Thar reach in summer?
53 degrees C
Jaisalmer is found on the ___ ___ —> opportunity for ___
Silk Road
Trade
Jaisalmer has grown by over ___ in a ___ and has over _____ inhabitants
1/3
Decade
600,000
Jaisalmer is known as _____ and has a historical fort which attracts ___ visitors each year
The Golden City
500,000
Opportunities for development: Mineral Extraction
Valuable ___ of minerals which are exported ____
Reserves
Around the world
Gypsum is used in making…
Plaster and cement
What mineral is used to make fertiliser?
Phosphorite
Kaolin is used as…
A whitener in paper
Jaisalmer has a valuable reserve of what?
Sanu limestone
Opportunities for development: Tourism
The Thar is a ___ tourist destination
Popular
Desert ____ on camels have become popular with ____ and wealthy ____
Safaris
Foreigners
Indians
___ ___ held each winter - locals benefit by providing __ and ___ and acting as guides
Desert Festival
Food
Accommodation
Opportunities for development: Energy
Rich ___ source
Energy
Extensive ___ __ deposits in parts of the Thar
Lignite coal
What has been constructed at Giral?
Thermal energy plant
Recently in the Thar there’s been a focus on developing ___ power
Wind
Jaisalmer Wind Park was constructed in ___ and is India’s ___ wind farm
2001
Largest
Ideal conditions for __ power generation
Solar
At Bhaleri solar power is used in…
Water treatment
Opportunities for development: Farming
Most desert inhabitants are involved in ___ farming
Subsistence
Commercial farming has been made possible by what?
Irrigation
____ __ Canal was constructed in ___ and has revolutionised farming
Indira Ghandi
1958
The Indira Ghandi canal has meant crops like ___ and ___ now thrive and other crops grown under ___ include pulses, sesame, __, and __
Wheat
Cotton
Irrigation
Maize
Mustard
Challenges of development: Extreme Temperatures
Often the temps exceed ___ degrees C and this presents challenges to both __ and humans
50
Animals
Working ___ in the ____ is virtually impossible
Outside
Heat of the day
High evaporation rates lead to…
Water shortages
Many animals and plants must adapt eg being ___
Nocturnal
Livestock need access to ___ to protect them from the sun
Shade
Challenges to development: Water Availability
Water supply is __ in the Thar and the population has grown, making it a ___ resource
Low
Scarcer
___ and ___ have also developed, increasing the demand for water
Farming
Industry
There are several sources of water:
Ponds, some of which are ___ and others are ____
Natural
Man made
There are few rivers and streams such as the River __
These flow only after ___ and most ___ are found alongside these rivers
Luni
Rainfall
Settlements
Some water can be obtained from underground sources (____) but this water is __ and low quality
Aquifers
Salty
Impacts of the Indira Ghandi Canal:
Commercial farming flourishes
Two areas that benefit are Jodhpur and Jaisalmer where over 3500 km squared of land is under irrigation
Provides drinking water to many people
Challenges to development: Accessibility
Due to the extreme ___ and presence of vast ___ areas there is a very limited road network across the Thar
Weather
Barren
High temps can melt ___ and strong winds often blow __ over the roads
Tarmac
Sand
Many places in the Thar are accessible only by __ and public transport often involves seriously overladen ___
Camel
Buses
Where is Malaysia?
South east Asia
What % of Malaysia is rainforest?
67%
What are the threats to Malaysia’s rainforest?
Logging
Road building
Energy development
Mineral extraction
Population pressure
Commercial farming
Subsistence farming
In the 1980s Malaysia became the world’s largest exporter of what?
Tropical wood
What is clear felling?
When all trees in an area are cut down
What is selective logging?
Only fully grown trees are cut down and trees with important ecological value are left
How does energy development threaten the rainforest?
Hydroelectric power (HEP) means that dams are built, causing flooding which damages forests
In 2011 the controversial Bakun Dam started generating electricity - the reservoir meant that…
Over 700km squared of forest and farmland was flooded
(Destroyed habitats and displaced indigenous people)
In the past, Malaysia’s government encouraged people to…
Move from urban to rural areas (transmigration)
Between ___ and ____, how many hectares of TRF were felled for settlers?
1956
The 1980s
15,000 hectares
How does mineral extraction impact TRF?
Rainforest cleared for mining and oil / gas drilling
Malaysia is the world’s largest exporter of…
Palm oil
During the 1970s large areas of land in Malaysia were converted to…
Palm oil plantations
Plantation owners receive _____ for producing palm oil, which has led to the growth of the palm oil industry
10 year tax incentives
Why is commercial farming negative for TRFs?
It is large scale and unsustainable, requiring large areas of TRF to be cleared for farmland
This impacts biodiversity / natural habitats, as well as the environment eg climate change
What is a positive of subsistence farming?
It is small scale and sustainable
What is a negative of subsistence farming?
“Slash and burn” fires can get out of control and damage large areas of rainforest
Why are roads constructed in Malaysia’s TRF?
To provide access to logging and mining areas, new settlements and energy projects
What are the negative impacts of road building on TRF?
Large stretches of land are deforested to clear space for roads
Animals are killed on roads
Roads can run through areas where indigenous people live, causing tension between indigenous communities and developers
How does deforestation impact biodiversity?
Destruction of habitats
Loss of plant and animal species, including possible medicinal plants
How does deforestation impact the soils?
Soil is now exposed to more rainfall, which washes away the nutrients on the top layer, leaving just the infertile soil below
Roots no longer bind the soil and it becomes loose, leading to soil erosion
How does deforestation impact the climate?
Reduced trees means:
1. Reduced photosynthesis, which takes carbon dioxide from the atmosphere
2. When trees are felled they release the carbon they’ve been storing
3. Transpiration cools the air and reduces moisture, so deforestation can cause TRF climates to become hotter and drier
What are the economic gains of deforestation in Malaysia? (Name four)
Development of mining / farming / energy leads to jobs
Tax revenue used to supply public services
Improved transport infrastructure
Raw materials eg palm oil and rubber
HEP is cheap and plentiful
Valuable minerals
What are the economic losses of deforestation in Malaysia? (Name four)
Pollution of water sources
Increasingly dry climate
Fires cause pollution and destroy forest
Rising temps could affect established farming
Plants that could bring medical benefits and economic profits may be lost
Climate change could have economic costs
Rainforest tourism would decrease
Why should TRFs be protected?
Biodiversity
Medicine
Resources
Water
People
Climate change
Why does biodiversity mean TRFs should be protected?
TRFs contain over half the plant and animal species in the world
Many still to be discovered
Why does medicine mean TRFs should be protected?
25% of all medicines come from rainforest plants
Over 2000 TRF plants have anti-cancer properties
What kinds of resources can TRFs have?
Valuable hardwoods, nuts, fruit and rubber
Why is water a reason to protect TRFs?
Rainforests are important sources of clean water
20% of world’s fresh water is from Amazon Basin
Why do people mean TRFs should be protected?
Indigenous tribes live in TRFs eg the Achuar tribe of the Peruvian Amazon
How do rainforests help the climate?
Absorb and store carbon dioxide
Prevent climate from becoming too hot and dry
Produce 28% of world’s oxygen
Brazil had the fastest rates of deforestation but…
The rate has fallen dramatically
Why are Brazil’s losses now the lowest on record?
Brazil’s govt has cracked down on illegal deforestation
They lead the world in conservation (over half the Amazon is protected)
They’re committed to reducing carbon emissions to tackle climate change
Consumer pressure not to use products from deforested areas has led to decline in cattle ranching
Every __ seconds an area of TRF the size of _____ is lost
2
A football pitch
An area of TRF the size of ____ has been lost
China
Why do rainforests need to be managed sustainably?
To ensure they remain a lasting resource for future generations
To allow valuable resources to be used without causing long term environmental damage to the environment
How can rainforests be managed sustainably?
Selective logging and replanting
Conservation and education
Ecotourism
International agreements
Use of tropical hardwoods
Debt reduction
Selective logging is completely _____ and was applied in Malaysia in ____
It involves planting ____ trees and avoids the destructive impacts of ___ felling
Sustainable
1977
Replacement
Clear
Conservation and education encourages ____ of TRFs through national parks and ____ ____
These can be used for education, ____ research and tourism
Preservation
Nature reserves
Scientific
Ecotourism aims to…
Introduce people to the natural world
Benefit local communities
Protect the environment for the future
Rainforests are now understood to be of ___ ___. International agreements have been made to ___ TRFs
Global importance
Protect
The Forest Stewardship Council (FSC) promotes sustainably managed forestry through…
Education programmes and its FSC-labelled products
Some donor countries and organisations _____ other countries’ debts in return for agreement that….
This is known as…
Reduce
TRFs will not be deforested
“Debt-for-nature swapping”
Define desertification
Where land is gradually turned into desert
Where does desertification usually occur?
On the edges of existing deserts
Desertification is a result of both natural (eg ____) and human (eg _____) causes
Drought
Mismanagement
How is climate change linked to desertification?
Resulting in drier conditions and unreliable rainfall in some regions (eg the Sahel, on the southern margins of the Sahara)
How is soil erosion linked to desertification?
Where vegetation is destroyed it exposes soil which cracks and breaks up, making it vulnerable to erosion by wind and rain
How is salinisation linked to desertification?
Rapid evaporation of poorly practised irrigation leads to surface salts building up, which kill plants
How is overgrazing linked to desertification?
Population pressure results in the limited vegetation supporting too many animals
How is over-cultivation linked to desertification?
More people need more food which exhausts the soil, causing it to become infertile
How is fuelwood linked to desertification?
Population growth increases demand
Trees that are stripped of branches eventually die
Where is Badia?
A dry, rocky desert in northern and eastern Jordan
Badia receives how much rainfall per year?
Less than 150mm
Badia was traditionally grazed by ______ Bedouin herders (the land could ____ before being grazed again)
Nomadic
Recover
What happened to cause desertification in Badia?
1991 - conflict (first gulf war in Iraq)
Overgrazing from sheep herders fleeing Iraq
Almeria, Spain, is Europe’s only…
Truly arid area
(Less than 300mm of rain / year)
In Almeria there used to be large areas of _____ farmland but mass ____ of the countryside meant land was _____
Irrigated
Depopulation
Abandoned
Terraces protecting Almeria’s soil from ____ fell into disrepair and rainstorms washed away soil from _____
Erosion
Hillsides
_____ moved into the Almeria area and _____ of their livestock led to removal of plants and soil _____
Shepherds
Over-grazing
Compaction
Large deposits of ____ rock that formed an underground store of ___ have been quarried for building
Gypsum
Water
Tourist destinations in Almeria, Spain use a lot of water eg ____ which receives __ million visitors a year and provides __% of the country’s GDP
Benidorm
4 million
1%
Commercial farming in hot deserts often involves what?
Irrigation
Too much irrigation can cause…
Salinisation (where too much salt in the soil reduces soil fertility and kills plants)
What are ponding banks?
Areas of land enclosed by low walls to store water
What are contour traps?
Embankments built along the contours of slopes to prevent soil from being washed away during heavy rainfall
How has desertification been managed in Badia, Jordan?
Locals have built stone walls to stop water running down slopes
This water is used to irrigate shrubs that are well adapted to the environment
These hold the soil together and provide grazing for sheep / goats
As soil conditions improve, plants have started to grow attracting animals
In some parts of the world hot deserts have been protected by making them into…
National parks
The Desert National Park in the Thar was created in ___ to protect ____ km2 of desert and reduce desertification
1992
3000km2
The ___ National Park is one of 4 desert national parks in the USA
It was established in ___ to protect a ____ near Las Vegas
Zion
1919
Canyon
Tree roots __ the soil together and branches provide shade, ____ for animals and ____
Bind
Grazing
Fuelwood
Appropriate technology involves…
Using methods and materials that are appropriate to their level of development
In Burkina Faso lines of “____ ____” have been used to reduce soil erosion
Locals build walls between 0.5m and 1.5m high along ___ of slopes
The walls trap water and soil, this has increased crops by __% and reduced desertification
Magic stones
Contours
50%
