Topic 8 - Forests Under Threat Flashcards
How is biotic and abiotic characteristics interdependent
1) warm and wet climates mean that plants grow quickly. The dense leaf cover protects the soil of wind and rainfall, while tree roots bind soil together to prevent erosion and nutrient leaching
2) Lack of wind means that plants rely on animals and insect for pollination. As a result speciies have formed symbiotic relationships to survive.
3) Plants can depend on other plant to survive e.g epiphytes which grown on other plants for sunlight. However, they depend on rain for nutrients.
4) Deforestation reduces co2 absorbed from the atmosphere, which adds to the greenhosue effedt and climate change.
How are plants and animals adapted to the climate TRF
Plants:
Emergent trees: tall trunks and only have barnches at the top to get light. They also have big butress roots which are shallow and wide.
Main canopy: only leaves at the top and provide shade dor planst at the bottom.
Undercanopy: can only surive where there are breaks in sunlight (young trees)
Shrub layer: large broad leaves to absorb as much sunlight
Other adaptations may include:
Thick,waxy leaves called deip tips which channel water off the leave to prevent fungi and bacteria growth blocking sunlight
Trees have smooth,thin bark to allow water to run off and protect against cold temperatures.
Plants drop their leaves gradually over the years. As a result grow all year round.
Animals:
Strong limbs e.g monkeys for protection and collect food
Flaps of skin to glide or wings to fly for protection and food
Nocturnal minimises danger and it is cooler during the night
Animals on the forest floor have poor eyesight but a sharp sense of smell
Jaguars can swim and have camouflage
Why does tropical rainforests have a very high rate of nutrient cycling and what does it do
1) trees are evergreen,so dead leaves and other materisl fall all year round
2) The warm and moist conditions mean fungi and bacteria decompose the dead organic mayter quickly. The nutrient released are soluble and absorbed.
3) Dense vegetation and rapid plant growth means nutrients are rapidly taken up by plant roots.
How are taiga plants and animals adapted to the climate
Plants:
Trees are evergreen as a result shed lesves all year and make use of the avilable light
They have needles instead of flat leaves- this reduces water loss from strong,cold wind due ro rhe surface areas
They are cone-shaped this results in heavy winter snowfall that can slide straight off branches without breaking them up
Animals:
Many large animals e.g caribou are migratory and move long distances for food
Many animals well insulated against the winter cold.
Some animals hibernate to conserve energy and survive
Some animals are camouflaged against the winter to hide from predators,
Why does the taiga have lower productivity, with less active nutrient cycling and lower bidoiveristy
Nutrient cycle:
1) trees drop needles all year round (most nutrients added are through runoff and leaching)
2) Despoite the constant leaf fall, low temp means that it takes a long time for the little to be broken down and added to the soil (infertile)
3) As a result plants grow slowly due to lacking nutrients
Why Taiga forests have low biodiversity:
Land was much colder and covered by ice until 15000 years ago. As a result species had little time to adapt (small variety). The Taiga forest is also less productive and nutrients take a long time to be returned and the growing season is relatively short.
Causes of deforestation and its contribution to deforestation in the TRF
Local demand for fuel wood- local people chop up trees for cooking or to burn charcoal
Mineral resources- ores only fond in the TRF. Explosives used to clear the material and create deposits.
Electricity- many TRV have large rivers. Buildings dams flood large areas of forest behind dams.
Commercial farming- forest is cleared to make way for cattle grazing, palm oil,soya plantations
Commercial hard wood logging- trees are felled dor furniture as well as to clear roads to transport trees.
Demand for bio-fuels - trees cut down to farm bio-fuels to limit greenhosue gas emissions
Subsistence farming- trees cutb doen and burnt to create an income.
Deforestation can cause: soil erosion as tree cannot bind the soil and rain/wind will leach the nutrients as trees cannot intercept the soil. Trees release co2 when cut and will not be able to absorb any more co2
Why is climate change an indirect threat to the health of the TRF
Temp increase can lead to droughts which can cause ecosystem stresss as plants and animals begin to die in the dry conditions.
Frequent or long periods of droughts can cause mass extinction of species.
Droughts may also lead to forest fires which destroy a large area of the plant further. However, create ash which is fertile for plant growth.
Direct threats from logging and pulp and paper production Taiga forest
Logging for softwood-tree cut down to be made into furniture,housing and matches which release co2 and destroy habitats
Pulp and paper production- felled trees are mashed into a pulp and used to make paper. Enhanced greenouse effect from transport , massive amount of water used to create paper, emissions released during manufacturing
Indirect threats from exploitation of minerals, fossil fuels and HEP potential Taiga forest
Exploitation of fossil fuels- trees cleared to extract gas and oil
E.g- tar sands can be processed into a fossil fuel found within the Taiga forest. Open pit mining or strip mining is used which digs up the land surface in stripsnro get ghe sand beneath causing large scale deforestation.
HEP- dams generate hydroelectric power from rivers in the taiga forest which flood large areas of land.
Exploitation of minerals- rich in minerals. Lots of trees are chopped down to make way for mines and access to roads
How does acid rain , forest fires , pest and diseases contribute to loss of biodiversity Taigai forest
Acid rain-
sulfur dioxide snd nitrogen oxides from burnt fossil fuels can dissolve into the atmosphere to form acids which are then deposited on plants and soil as acid rain. This can damage plant leaves and make it harder for them to cope with the cold. It can also kill microorganisms within lakes and streams.
Forest fires-
wildfires are natural and allow new growth and regeneration. However, duento climate change drier conditions in the Taiga forest results in more forsest fires. This can reduce numer of trees and destroy habitats, change distribution of animals and make it more difficult for migratory animals to find food.
Pest and diseases-
Taiga forest have a lacking variety of species. As a result invasive insect that are specific to one organism can spread and multipy easily. Additionalky, global warming has made ir easier for pests and disease causing pathogens to survive and are attacking more frequently. This threatens the Taiga population
Advantages and disadvantages of global actions designed to protect the TRF species and areas
Advantages of REDD:
Scheme that rewards forest owners in poor countries for keeping forests instead of cutting them down
Deals with direct cause of deforestation // biodiversity not lost // cheap option and beneficial for everyone
Disadvanatges:
Deforestation may continue in areas // aspect unclear (areas can be cut down but replanted with low biodiveristy although still recieve a reward) // pevents activities which local people require for a living.
Advantages of CITIES:
Agreement to tightly control trade in wild animals and plants
Trade of endangered species controlled globally // encourages sharing information between countries which raises awareness of threats to biodiversity // help different sectors work together
Disadvantages CITIES: Individual species are not protected from poaching, it doens’t protect their habitat
Rule are unclear e.g trade on ivory
Not all countries are members -some promote trade of endangered animals
Challanges of achieving sustainable forest management
Sustainable forest management- forestb is used that prevents long term damage whilst allowing people to benefit from the resources it provides in the present and in the future.
Challenges include:
Economics- benfits only in the long term // sustainable forestet is more expensive so it is difficult to persuade private investors to adopt sustainable methods // many forestry schemes are funded by government departments and NGO’s if the priority of these companies change funding can stop
Social- provides fewer jobs for people then conventionsl forestry, many locals do not benefit. Some turn to illegal logging,poaching and animal trafficking // Sustainable forests unable to provide enough resources to match with the increasing demand
Environmental- trees can be replaced but not restored. Trees that are replanted for logging in the future can grow slowly companies may chop down more trees then which are replanted.
Why are alternative livelihoods good to protect the TRF
Ecotourism: tourism that minimises the damage imposed onto the environment and benefits local people. However, only a small number of visitors are allowed although the damage to environemnt is minimised. This also provides a source of income to local people and raise awareness of conservation issues and bring money to rainforest conversation. However, countries cannot only depend on ecotourism.
Sustainable farming: protects the land so it remains productive. This includes agro-forestry: trees and crops are replanted at the same time. The trees bind the soil and leaves protect plant from rain.
Green manure adds nutrients to the soil as they grow and plants to maintain soil fertility
Crop rotation- crops moved to different fields each year with one left empty so the soil can recover.
Challanges of creating and maintaining protected wilderness areas, national parks and sustainable forestry in the Taiga
Creating wilderness areas:
Strengths- human activity is banned (highly protected) // covers a large area so large scale migrations can take place
Challanges- hard to police // economic pressure on governments from logging, mining and energy companies who want to use the resources // pressure from companies and tourists to build roads
Creating a national park:
Strengths-protect particular species // covers a large area // unsustainabke human activity such as logging ans mining not permited // good access for tourists and recreational users
Challenges- takes the indigenous people into account // tourism may be required to pay for conservation but access road, infratstructure and pollution from tourists harm the ecosystem
Sustainable forestry:
Strengths- limits placed on the number of trees felled or the size of clear cut areas to allow regeneration // selecive logging means some trees remain to become a new forest
Challenges- countries struggle to enforce restrictions e.g Russia has a lot of illegal restrictions // lack of clear management or info about ecosystems // different groups disagree about rule and restrictions.
Reasons for conflicting views on protecting or exploiting forest and natural resources of Taiga
Protections:
Taiga forst store lots of carbon - deforestation releases lots of carbon dioixd which causes global warming.
Species only adapted to the Taiga conditions are threat at exticntion if the Taiga forest is exploited
Many indigenous people depend on the forest for their traditional way of life.
Exploitation:
Demand for resources e.g food,water,minerals are increasing as population increases
Forest industrues e.g logging and mining provide lots of jobs (25 thousand people in Canada have forestry and logging jobs)
Exploitation generates lots of wealth (forest industry in Sweden gains US 15 billion each year)
