Biodiversity A2 GEOGRAPHY EDEXCEL

BIODIVERSITY

Dr Jenifer Hill UWE lecture on tropical rainforests

·         Fortress conservation = building wall around the cleared area like a fort around an area of rainforest

·         New conservation = eco tourism using people as well as protecting RF

Epiphytes = plant that grows on another plant e.g. fern

The rainforest also has canopy layers. These allow different plants to get different amounts of light. They are all adapted to their position.

Rainforest is on the equator so they usually receive a lot of sun. They are in a zone of inter tropical convergence. 50% of rainforest is in central and south America. Malaysia and Australia have 25% and central and west Africa has 20% of RF.

Ø  Plant adaptation e.g. fan palms have extended leaves to catch extra rainfall. The leaves are segmented to drain excess water that might cause the plant to rot. They also have drip tips to let water drain away.

Ø  Strangler figs – start at top of tree then drops a seed, strangles host. Fig branches catch sunlight. The host dies. Tree has a hollow trunk for the strangler fig.

Half of the world’s species are in RF. High species diversity leads to:

·         Consumptive use value (value of nature consumed already e.g. firewood, meat)

·         Productive use value(makes money. Nature commercially harvested and passed through markets e.g. timber, medicine)

·         Non consumptive use value (value derived from ecosystems e.g. watershed production, carbon regulation)

·         Existence value (least listened to. Ethically preserving species right to exist)

Destruction = logging, animal pasture, resettlement schemes, development, commercial agriculture

Destruction makes a gap between seeds and animals that pollinate seeds. Many animals cannot migrate across gap made by destruction. This reduces the genetic fitness of a population and reduces the number of species and makes animals endangered.

RF has been fragmented by agents of destruction. They need to understand the ecology; they also need to understand influence of fragmented area shape and isolation of biodiversity.

·         Irregular shaped fragments of RF cut down means that there is more edge, forest edges have higher number of species

·         There is increased sunlight and temperature along the forest edge

Eco tourism in Peru

Eco tourism creates positive links between habitat conservation and local cultures

EXAMPLE: Rain Forests Expeditions (private company)

·         They aim to educate and research with sustainable conservation

·         In 2016 the lodge and all of their buildings will be passed onto the local community

·         All of the staff are native people from the local communities

·          They conduct low environmental impact tours

·         They also made a contract with the local people to ensure it is fair

·         60% of their profits go to the local people to help their community

·         They prohibit the hunting of wildlife

·         In 2007 the local community gained $148,000 from the RF expeditions company. Three quarters of the money was divided amongst local people and the rest was used for school construction and investment into education

·         10:1 is their guide to tourist ratio

·         They educate the local people in tourism so that they can run tours for tourists.

Alien species = those which are not native to an area, but have been introduced usually by human activity

THREATS TO BIODIVERSITY:

1.       Climate change rising sea levels. Niche species most endangered eg coral bleaching at great barrier reef due to increased water temperatures

2.       Population increase and resource consumption e.g. cod fishing enforced quotas by EU to stop them becoming extinct

3.       Economic systems promoted by governments and businesses that fail to value the environment

4.       Pollution e.g. oil spills

5.       Deforestation e.g. Borneo, Peru, Malaysia, RF

6.       Ignorance e.g. people and governments

7.       Invasive species e.g. bugs through human action e.g. red squirrel

8.       Over exploitation e.g. fishing, RF for medicine and timber wood. Land soil becomes bad

9.       Habitat change e.g. Tropical rainforests

Eutrophication = process by which fertilizer causes rapid algal and plant growth and the depletion of oxygen available for fish and other aquatic species

World Resources Institute asses threats to biodiversity by a scheme called ‘’count it, change it, scale it’’ They gather data, and then use the research to influence business policies and civil society action.  They test projects with communities. They then expand their efforts globally.

CASE STUDY = SOUTH WEST AUSTRALIA

Forest, woodland, shrublands have high numbers of endemic plant and reptile species. The threats facing biodiversity in Australia are agricultural expansion and high levels of fertilizer which can result in habitat loss. Also a threat is the introduction of invasive species e.g. foxes and cats which threaten native fauna.

CASE STUDY = ATLANTIC FOREST

It has over 20,000 plant species and 950 kinds of birds yet less than 10% of original forest remains. Over 24 critically endangered species. The threats to the Atlantic forests biodiversity include habitat loss caused by development and expansion of sugar cane and coffee plantations. Another threat is the urbanisation due to rapid expansion of cities such as Rio de Janeiro and Sao Paulo.

Endemism = where something only occurs in one specific area e.g. dodo bird was endemic to Malicious

 

Exam question: Describe the distribution of threatened hotspots and threats they face.

Extra task – split threats to biodiversity into global and local.

Global distribution of biodiversity

·         TR contain 50% of worlds species in just over 7% of worlds land area

·         TR account for 80% of all insects and 90% of primates

·         Brazil, Indonesia and Madagascar contain over 55% of the worlds mammals

·         Tropical America has about 85,000 species of flowering plants compared with 11,300 in Europe

Global distribution of species richness varies by latitude. Patterns can be explained by variations in land mass.

Biomes = Large global ecosystems usually have many types of vegetation such as TR. Each biome contains communities of plants and animals that can be linked to soil types. TR is the most productive biome.

Biomass = total amount of organic matter in a given area

(NPP) Net primary productivity energy = calculated as energy fixed by photosynthesis minus that lost though respiration – measured in kg per square metre per year.

Biodiversity = total number of species in a given area or genetic variety of an area. Hotspots are areas that have high concentrations of biodiversity e.g.  South East Asia, India, Burma, Philippines.

Biodiversity =

·         Species diversity

·         Variations within species

·         Interdependence within species (ecosystem diversity)

Organic productivity = or primary productivity is a measure of how quickly vegetation grows i.e. at the rate at which organic matter is produced. TR produces the highest amount of organic matter due to their large biomass resulting from constant high temperatures and heavy rainfall = large growing season.

Case study NOT TYPED UP = ANWR (arctic national wildlife refuge)

·         Provisioning services- products obtained from ecosystems e.g. food, wood, fuel, medicine

·         Regulating services- benefits obtained from regulation of ecosystem processes e.g. air quality, water, erosion, natural hazard regulation, water purification, waste treatment

·         Cultural services – non material benefits that people obtain from ecosystems e.g. spiritual and religious values, knowledge systems, cultural heritage, ecotourism

·         Supporting services – those that are necessary for the production of all other ecosystem services their impacts on people are indirect e.g. soil formation, photosynthesis, nutrient cycling, water cycling

Carbon sequestration = trees absorb co2 and let out 02. Co2 is stored in leaves and branches and this regulates pollution in the atmosphere.

Daintree rainforest – Australia ‘wet tropics’ deciduous forest

Tourism in daintree rainforest worth $41.7 million a year , creates 3500 jobs, 70% tourists travel there independently.

Plants take up nutrients from the soil, when they die they replace these and this creates a cycle. If deforestation takes away these trees then there is no nutrients put back into the soil, making the soil not fertile for crop growing.

Threats to biodiversity can be managed through:

1.       Biodiversity protection

2.       Economic incentives

3.       Education

4.       Limiting development

Conflict = economic development vs environmental protection 

Factors influence biodiversity:

·         Climate – controls distribution of biomes.

·         Precipitation – can depend on season, how reliable rainfall is type of rainfall and growing seasons.

·         Temperature- This influences vegetation. Plants begin growth at 6degrees, they photosynthesis at 10 degrees, they suffer light stress at 35 degrees.

·         Light intensity – This affects photosynthesis. Tropical ecosystems receive most incoming radiation and have higher energy inputs.

·         Winds- This increases the rate of evapotanspiration.

·         Endemism – If biodiversity is high, the rates of endemic species is usually high too.

·         Human activity – biodiversity is under attack from human activity. This causes habitat change, invasive species, pollution and climate change.