Selected Habitat - Tropical Rainforest

Question 1

General

Answer 1

Most biodiversity terrestrial ecosystem
Rate at which new specie discovered suggest over 1/2 terrestrial specie live in tropical rainforests
Rainforest only cover around 10% earths land surface

Question 2

Ecological feats

Answer 2

Tropical climate dev. Long time stable — long evolution to abiotic and biotic conditions
Lots of species - some rare, v small range tolerance - vulnerable to extinction from small env change

High light — high photosynthesis— lots food energy rich food web
Constant warm temp, reg rainfall - grow all yr w/out seasonal change - reliable food supplies all yr - no need migrate/hibernate.
Stable abiotic conditions and no season fluctuations- less need species to adapt and evolve further, main survival pressure = biotic factors
High light levels and complete. for light —> tall trunks and energy invested into wood trunk.
Smaller plants denser chlorophyll + pigments absorb wavelengths that pass through canopy.
Epiphytes access light, nutrient, water
No seasons- plants can flower at different time reduce competition of service of pollinators.
Nectar, seeds fruits available all yr - animals that feed on veg don’t have long no food periods

Question 3

Importance

4

Answer 3

High biodiversity
Forest resources
Soil maintenance
Climate maintenance

Question 5

Importance forest resources

Answer 5

ESP as long distance transport easier -imported across world

Timber - house construction 
Fibres - hemp rope
Resins/oils - rubber - tyres, palm oil
Food - cacao, pineapple 
Medicine - cinchona tree produce quinine - prevent malaria

Question 6

Importance

Climate maintenance

Answer 6

Downwind rainfall.
1/2 rain amazon rainforest from transpiration somewhere else in forest.
Carbon sequestration- photosynthesis

Question 7

Importance soil maintenance

Answer 7

Warm moiste - vegetation decay quick and nutrients rapid reabsorbed by trees - v shallow soil.
Veg cover and roots stop soil washed away/ eroded - intercepts and hold soil together.
Forest clearance —> soil erosion

Question 8

Threats
(3)
(6)

Answer 8

1 Fuelwood collection - faster then replant/growth
2 timber harvesting- transported/ origin country
3 clearance for alt. Land use
+ subsistence ag - slash burn move on - need gap b4 farmed again, time to be recolonised
+ commercial - cash crops, cattle ranch- soils eride and infertile - abandoned not recolonised easily
+ mineral extraction- valuable deposits metal minerals —> pollutionturbid drainage h2o, cyanide Mercury h2o pollution.

     \+ reservoir - HEP Tucuri Brazil 2850km2
      \+ CC - affect species - droughts - more reg. intense forest fire - boil tree sap. Cloud forest Costa Rica need humidity esp epiphytes like orchids absorb h2o from bark surface. Rainforest replaced w savanna sometimes 
      \+ tourism - large no. Visitors

Question 9

Conservation efforts

Answer 9

Cameroon Korup National parks 1260km2 tropical forest high biodiversity many endemic
Useful plants for medicine a plant Acistrocladus korpensis alkaloid chem — HIV treatment and anti malarial drug trials

Question 10

Conservation efforts

Debt for nature swap

Answer 10

Debt for nature swap

Eg US cancelled $24m from Guatemala in return for conservation

Question 11

Importance

V high biodiversity

Answer 11

V high biodiversity- increase chance of finding resources.
No cold winters kill off herbivores- protect-selves from eaten - toxic Chems eg alkaloids medicinal use.
Animals also produce medically valuable chems avoid predation - esp. w/out claws / teeth - venom catch prey.
Frogs + reptiles more likely produce useful chems then mammals / birds