Ecosystems - (P1-SEC B) Flashcards
DEFINITION
ECOSYSTEMS
- system in which organisms inetrcat with eachother/with their environment
define
abiotic
- non living things
- e.g air, water, heat
define
Biotic and 2 types ?
living things
e.g animals , plants
FLORA : plant life occuring in a partiuclar region/time
FAUNA: animal life of any particular region/time
3 features of a food chain?
Producers: convert energy from environ into sugars
Consumers: GET ENERGY FROM SUGARS from producers
Decomposers: Breaks down plant/animal material and return nutrients into soil
difference between food chain and food web?
Food chain- SHOW DIRECT LINKS BETWEEN PRODUCERS/CONSUMERS IN A SIMPLE LINE
Food web : SHOW ALL CONNECTIONS BETWEEN PRODUCERS/CONSUMERS IN A COMPLEX WAY
What is nutrient cycling?
decomposers help recycle nutrients making them availabe again for growth of plants/animals
1. producers take up nutrients from soil for growth
2. consumers eat producers using nutrients fro growth
3. decomposers break down organic matter (when consumer dies) and return nutrients to soil
changes of ecosystems due to HUMANS?
- EUTROPHICATION from fertilisers (fish die due to lack of 02)
- ponds are DRAINED for farming (less habitats)
- WOODS cut
- Hedgerows removed to increase field size (less habitats)
cause of variations in vegetation?
- ocean currents
- wind
- distrubution of land/sea
location, characteristics
Desert
Location : 30 N/S equator
characteristics : high temp (day), low temp (night), high pressure, low rainfall
location, characteristics
Polar
location: Arctic/antarctic
characteristics: cold air sinks at Poles
- very low temps / DRY
location, characteristics
Deciduous/confierous forest
location: 50-60 North of equator
characteristics: Deciduous shed leaves in winter to retain moisture
- conferous retain leaves in summer
location, characteristics
Temperate grassland
location: 30-40 N/S equator
characteristics: - warm, dry summer
- cold winter
location, characteristics
Mediteranean
location: 40-45 North Equator
characteristics : hot, dry summer
-mild winter
location, characteristics
Tropical Grassland
location: 15-30 N/S equator
characteristics: Dry season , hot (fires)
- thunderstorms in wet season
location, characteristics
Tundra
location: from arctic cirle to 60-70 north
characteristics : low growing plants retain heat
- cold windy dry
Location, characteristics
Tropical Rainforests
Location: close to equator
Characteristics: tall trees (45m)
- variety of wildlife
- wet - low pressure, so air rises –> clouds
- high temps (27C)
- varying rainfall (2000mm/yr)
soil in tropical rainforests ?
- infertile
- leaves decompose rapidly in hot/humid conditions
- rain carries away/dissolves nutrients –> LEACHING
How ware plants adapted in top canopy ?
- get most light
- leaves have flexible bases to turn to sun
- leaves have ‘drip tip’ to allow rain off leaves
how are plants in lower layer adapted?
- THIN, SMOOTH BARK - water flow down easily
- BUTRESSESS- rdiges support bases of tall tress/transport water
- EPHIPHYTES - live on branches high in canopy to seek sun
issues related to biodiveristy?
- human exploitation –> decrease biodiveristy
- endangered species
- loss of biodiverity—> less ecoystem productivity
CASE STUDY
MALAYSIA
location
-SE asia
- made up of Peninsula and East Malaysia
- 67% covered with rainforest
causes of deforestation to malaysia rainforest?
REMPCLS
LOGGING: only fully grown trees cut down, after CLEAR FELLING WAS POPULAR (cut trees in an area)
- Malaysia world’s largest exporter
ROAD BUILDING: to provide access to mines, settlements, energy projects
ENERGY DEVELOPMENT : more dams planned to boost electricty supply
- Bakun Dam (205m) is Asia’s highest dam outside China
MINERAL EXTRACTION: rainforest is cleared for mining, roads, extracting oil/gas
POPULATION GROWTH: - in past, poor mved to rural areas (TRANSMIGRATION)
- 15000 HECTARES FELLED for settlers
COMMERCIAL FRAMING: - converted to palm oil plantations
- Malaysia is world’s largest exporter of Palm oil
SUBSISTENCE FARMING : - in past, used to grow food in clear pockets of land
- METHOD 1 TO CLEAR LAND = ‘SLASH AND BURN’
- burning created valuable nutirents for growth
impacts of deforestation
SOIL EROSION - removal of soil by wind/water
LOSS OF BODIVERISTY
CLIMATE CHANGE- trees transpire giving off mositure, so deforestation mean less moist air
ECONOMIC DEVELOPMENT
EG of biodiveristy in Malaysia?
Biodiveristy in Main Range of Peninsular Malaysia
- largest area of continuous forest
- 600 species
- highland forests are home to 25% of plant species in Malaysia
gains and losses in economic development due to deforesation?
GAINS : -more farms/mines –> more JOBS
- companies pay taxes to government to improve services
- better transport opens up new areas of industrial development/tourism
LOSSES: - water pollution/dry climate leads to water shortage
- fires cause pollution
- plants may become extinct
value of tropical rainforests?
BIODIVERISTY
CLIMATE CHANGE : - trees absorb CO2
CLIMATE : 28% O2 comes from rainforests
PPL: idigenous tribes live in harmony in rainforests
WATER: 20% water comes from Amazon
RESOURCES: provide hardwood, nuts,rubber
MEDECINE: 25% medecines coem from plants in rainforests (2000+ plants have anti cancer properties)
susitainable management strategies of rainforests ?
SELECTIVE LOGGING /REPLANTING- clear felling is damaging/ logging is more sustainable
CONSERVATIONS/EDUCATION: can be preserved in national parks/ can be used for education/tourism
ECOTOURISM : - intropduce ppl to natural environment/ income from tourism used to retan/protect forest
INTERNATIONAL AGREEMENTS: help protect
eg of international agreements to manage tropical rainforest?
hardwood forestry:
FSC is international organisation promoting sustainble forestry
- FSC edcuates manufacturers/consumers about need to buy sustainable hardwood
debt reduction:
- reduce debts in return for agreements that rainforest will not be deforested
example of small scale ecosystem and the food chain
freshwater ponds
PRODUCERS: algae/microscopic plants convert energy –> sugar
CONSUMERS: Larvae
SECONDARY CONSUMER: fish
DECOMPOSERS: bacteria , worms, maggots
