content - forests Flashcards
(40 cards)
1
Q
How biotic and abiotic characteristics are interdependent in a tropical rainforest
A
- Climate
- Soil
- Water
- Plants
- Animals
- Humans
2
Q
how plants are adapted in TRF - 4
A
- stratified layers
- buttress roots = stables very tall trees
- drip tips = downward sloping leaves = surface water runs off quickly = otherwise moss + algae would grow on it = blocking the light
- tall trees = called emergents = 50+ metres tall = compete for light
3
Q
how animals are adapted to TRF
A
- camouflage = avoid predators eg. Chameleons can change their skin colour to match surroundings
- better grip + balance = powerful legs adapted to be able to grip branches
4
Q
Why does the tropical rainforests have a very high rate of nutrient cycling w
A
- fast decomposition
- leaching
5
Q
why does the TRF have high levels of biodiversity
A
- conditions for plant growth so good = allowing ecosystem to support thousands of diff species
- TRFs are ancient ecosystems = they have developed over 100 / 1000s of years = many species have adapted + evolved to meet the needs of the rainforests
6
Q
How biotic and abiotic characteristics are interdependent in taiga
A
- -Climate - Soil - Water - Plants - Animals - Human
*
7
Q
how are plants adapted to the taiga
A
- Cone shaped needles leaves // pine needles = small SA = less water loss // dark green = more photosynthesis = more light absorption // very little sap = do not freeze easily + can continue to operate in cold conditions
- grow close together = grain protection from the wind
- conical shape = downward facing branches = so the snow doesn’t accumulate and break the branch = it slides off
8
Q
how are animals adapted to the taiga
A
- Migratory animals = migrate south to warmer conditions 300 vs 30
- thick fur coats for insulation
- smaller ears / short tails = avoid frostbite
- ability to hibernate = bears build up fat reserves in the summer = hibernate in the den through much of the winter = enter a sleep - like state
- winter camouflage = white coat = away from predators
9
Q
Why does the taiga have lower productivity
A
- taiga plant growth limited to the short summer = biomass small = productivity is small
- decomposition of the litter layer is small and even stops during the winter deep freeze = soil as low nutrients level
- only a few specialist plant species can survive the taiga climate - biodiversity is low overall
10
Q
why does the TRF have higher productivity
A
- long growing season
- high temp + rainfall
11
Q
why does the taiga have less active nutrient cycling and much lower levels of biodiversity
A
- short growing season
- only specialised plants can = pine needles = acidic soils
- very cold
- low levels of decomposition
12
Q
causes of deforestation in TRF
A
- commercial hardwood logging
- subsistence and commercial agriculture
- local demand for fuel wood
13
Q
how demand for biofuels, mineral resources and electricity (HEP) contribute to deforestation
A
- clear land
- creation of HEP stations in the Amazon Basin has resulted in large areas of forest being flooded to create the reservoirs and dams. The flooding of the Balbina dam in Brazil resulted in the loss of 920 square miles of tropical rainforest.
14
Q
Why climate change is an indirect threat to the health of tropical rainforests;
A
- ecosystem stress = species not adapted to deal with heatwaves = stress
- drought = cause a northward shift in the atmospheric system that brings wet weather to TRF = do not bring as much rain to the rainforests = hotter + drier = higher risk of forest fires
15
Q
taiga direct threats
A
- logging for softwood
- = removes trees = no trees = mo pine needles = lower soil nutrients =
- logging technique used is clear cutting = trees cut down + transported to sawmills for pulp and paper production
16
Q
taiga indirect threats
A
from the exploitation of;
- minerals
- fossil fuels
- HEP potential.
side effects
- oil spills = Russias oil industry spills 5 million barrels of oil a year = very damaging to taiga because drainage is poor = oil doesn’t get washed away = as decomposition is very slow = oil remains in ecosystem for a very long time
17
Q
how does acid rain contribute to a loss of biodiversity - TAIGA
A
- caused by fossil fuels which are burnt releasing chemicals eg. sulphur dioxide + nitrogen oxides = react with oxygen + water = form acid rain
- plants are damaged by the acid rain = when acid gets into taiga soils / lakes / ponds = kills insects and their eggs = means fewer insects to feed migrating bird population
- acid = kills soil microbes = prevent nutrients from entering soil = weakens plant species = less resistant to extreme winters
18
Q
how does forest fires contribute to a loss of biodiversity - TAIGA
A
- caused by lightning strikes or human activity eg. hunters lighting camouflage fires
- taiga biome is adapted to forest fires = ash left after a fire is nutrient - rich + benefits plants = however only adapted to fires every 800-1000 years = much more frequent in recent years due to climate change = YOUNG SAPLINGS BURNT BEFORE THEY CAN GROW TO REPLACE OLD TREES
19
Q
how does pests and diseases contribute to a loss of biodiversity - TAIGA
A
- caused by fungus + mould species that damage conifers needles / trunks / roots
- eg. silkworm = spread into eastern Siberia in early 2000s = killed plants
20
Q
?Advantages and disadvantages oF GLOBAL ACTIONS
A
- CITES - convention on international trade in endangered species of wild flora + fauna // aims to prevent international trade
- REDD - reducing emissions from deforestation and forest degradation - UN scheme that advises governments how to reduce the rate of deforestations + replant. = it arranges large sums of money to fund these schemes from world bank
- NATIONAL PARKS
21
Q
why deforestation rates are rising in some areas but falling in others - TRF
A
RISING
- DEMAND eg. soya beans
FALLING - AMAZON RAINFOREST BRAZIL
- due to the International price for soya beans crashing in 2005
- TNCs came under pressure from environmental groups
- Brazilian gov increased its commitment to protection = billion dollar REDD fund = new laws
22
Q
What is the challenge of achieving sustainable forest management - TRF
A
- expansion of pasture for beef cattle = deforestation rose again in Brazil in 2015
23
Q
why alternative livelihoods might better protect the remaining tropical rainforest.
A
- sustainable forest management = aims to prevent damage in a way that will benefit the local people
- ecotourism = creates jobs for local people = eg. forest guides = tourists spend money
- sustainable farming training programme = involves teaching people about farming techniques
24
Q
What are the challenges of creating and maintaining protected wilderness areas - taiga
A
- aim to preserve the taiga biodiversity + productivity
- areas of active ecosystem management
- protecting wilderness areas = park rangers will sometimes have to CULL ELK = not enough big predators to keep ELK down
- too many elk = saplings get eaten instead of going into trees
25
What are the challenges of creating and maintaining national parks - taiga
* tourists = damage the ecosystem = litter
* migration = taiga species often migrate across long distances
* money = taiga has oil + gas = gov face pressure to exploit this = can lift countries out of poverty
* pollution = taiga easily damaged by atmospheric pollution = but need to be close to cities for tourists to visit them
* BANFF NATIONAL PARK
26
What are the challenges of creating and maintaining sustainable forestry - taiga
in sustainable forestry = trees that are cut down are replanted with native taiga species // whole forest carefully monitored
* expensive
* requires long-term planning
* only possible for large companies to when international organisations provide funds
27
Reasons for conflicting views on protecting or exploiting forest and natural resources in the taiga
* forestry = using the forest for timber, sustainably in countries such as Canada with strict controls on logging = Russian gov unsustainable
* mining + energy production = both Canada + russia as the two countries with the most taiga have allot of mining + energy production = generates wealth + jobs = 380,000
* indigenous people = wish to maintain traditional uses of resources eg. hunting
* recreation + tourism = in both North America + russia people go to relax + international tourism
* consumers of taiga products = paper
28
location of tropical rainforests
within 20 degrees north and south of the equator
29
nutrient cycle TRF
* biggest store = biomass
* when leaves or braches drop into the litter store - they decompose very quickly + are absorbed by plants
* constant rainfall = leaching = low soil nutrients
30
what is leaching
water washes away minerals and salts
31
how many plants/ animals are there in TRF
in island of Madagascar = 14,000 species of plants + 250,000 animal species
32
5 main layers of TRF
* herb layer
* shrub layer
* under-canopy
* canopy
* emergent layer
33
taiga climate
* subarctic climate
* average temp of -40 degrees in winter
* average temp of 16 in summer
* low rain = less than 500mm
34
nutrient cycle - taiga
* litter is biggest store = slow decomposition
* litter store = mostly made up of pine needles from coniferous trees of the taiga forest = these decompose slowly
* as nutrients take a long time to get in the soil = soil can not support a large biomass
* pine needles = acidic = soil only suitable for certain species
* only coniferous / mosses / lichens can survive
35
nutrient cycle - taiga
* litter is biggest store = slow decomposition
* litter store = mostly made up of pine needles from coniferous trees of the taiga forest = these decompose slowly
* as nutrients take a long time to get in the soil = soil can not support a large biomass
* pine needles = acidic = soil only suitable for certain species
* only coniferous / mosses / lichens can survive
36
what is subsistence and commercial agriculture
commercial agriculture
* crops are grown to make profit = leading cause of deforestation
* Brazilian rainforest clearance to grow sugarcane
* SOUTH EAST ASIA = forest been replaced by palm oil plantations = crops is Hugh demand for BIOFUEL = to replace fossil fuels
subsistence agriculture
* farm to feed themselves + family
* trees are cut down on a small plot + the undergrowth are burned = crops then planted
* nutrients leached out + weed growth takes over
* population growth = in past cleared land left for a time for natural planst to recover = not anymore / reused often
37
what is commercial hard logging
* selling rainforest timer for money
* in past Govs did this to pay off international debt
REASONS
* demand = high demand for tropical hardwood timber = especially ROSEWOOD = very dense / pink coloured + fragrant
* poverty = illegal logging pays well
* corruption = police + gov officials allow logging to happen for money
38
open cast mining - TRF
* rainforest on top of valuable minerals
* roads to access mines
* lots of deforestation
39
advantages + disadvantages of REDD
+ve
* provides international expertise to develop best approaches to tackling deforestation.
* funding that REDD can access is very attractive to governments = backed by UN
-ve
* deforestation levels still High
* REDD is vague about what counts as a forest for replanting = some cases funding has been given to projects that have replanted areas with PALM OIL TREES
40
advantages + dis of CITES
+ve
* large international influence - 181 countries have signed up
* targeting the right problem = most trade in endangered species products in international eg. rosewood timber
* protects over 35,000 species
-ve
* can not monitor all 181 countries = difficult to check that countries are doing all they can do
* illegal trade still increasing = because of high demand
