Ecosystems - The Sundarbans

Some facts about the Sundarbans:

• The Sundarbans mangrove forest is located at the delta of the Ganges, Brahmaputa and Meghna rivers in the Bay of Bengal.
• As well of mangrove forests the area is also covered in jungle.
• One third of the area is covered in water.
• The area has high biodiversity, including 260 bird species, tigers and crocodiles.
• Serves as a protective flood barrier for millions of inhabitant. 

Management

• 3 sanctuaries with a total area of 346,000 acres protect the landscape.
• It is an UNESCO World heritage site.
• To visit the area a permit is needed from the Divisional Forest Office.
• A guide is also necessary to reach the reserves.
• Its a Ramsar site.
• The endangered Royal Bengal tiger sometimes gets into the villages and instead of the villagers shooting them they have been taught how to control the tigers.

Exploitation

• Fertile soils have been subject to intensive agriculture.
• The rapidly expanding shrimp farming industry is a significant threat to the mangrove forests of Bangladesh.
• Illegal cutting, encroachment of forest areas and illegal poaching of wildlife. 
• Forest ecosystem also has become vulnerable to pollution. 
• Threats arise from global climate change, especially sea level rise. 

Ecosystems - Biodiversity

Biodiversity is the variety of life found on the planet.

Value:

• Loss of biodiversity can make ecosystems less stable and vulnerable.
• Plants remove carbon dioxide and provide oxygen.
• Plant communities are essential in the hydrological cycle. Transpiration recycles water back into the atmosphere. Also act as interceptors and aid infiltration.
• Healthy forests are a source of fuelwood.
• Food supply - 90% of the worlds calorie intake comes from 30 plants.
• Used for medicines.
• Can reduce floods.
• Supports traditional, old communities.
• Leisure use.

Threats:

• Habitat destruction
• Global climate change
• Disease
• Invasive species
• Over-exploitation
• Pollution
• Habitat fragmentation 

Ecosystems - Deforestation

Causes:

• Agriculture
• Logging
• Cattle ranching
• Urbanisation
• Infrastructure
• Hydroelectric projects
• Fuelwood
• Mining
• Oil extraction

Consequences:

• Loss of biodiversity
• Land degradation
• Climate change
• Mudslides
• Flooding
• Displacement of indigenous people

Western Australia

Australia has lost nearly 40% of its forests, but much of the remaining, but much of the remaining vegetation is highly fragmented.

Between 1990 and 2010, Australia lost an average of 0.17% per year.

Without clear policies to regenerate degraded forests and protect existing tracts at a massive scale, Australia stand to lose a large proportion of its remaining biodiversity.

Reasons for deforestation:

• Land clearing for agriculture. It increases the land value.
• During 1880s, broad scale vegetation removal was done for the expansion of sheep and wheat industry.

Consequences:

• 7% of the agriculture area of western Australia is suffering from saline water draining for deforested areas which affect downstream water quality. When forests are cut, the salinity of the soil can greatly increase.
• Studies in Australia's wet tropics show that soils have limited capacity to recover from deforestation. Estimates say that land degradation costs about $1bn annually.

The Congo Rainforest

In the Democratic Republic of Congo alone, 40 million people depend on the rainforest.

Satellite pictures reveal that deforestation has fallen by a third since 2000 but still losing 2000 km² a year. Schemes from the UN offer financial incentives to keep the forest in tact.

Reasons for deforestation:

• Transport infrastructure for logging
• Unregulated mining
• Fuelwood

Consequences:

• By 2050 forest clearance in the DRC will release a total of up to 24.4 billion tonnes of CO2.
• There has been a more than 60% drop in the region's forest elephant in less than a decade.

Ecosystems - Rainforest Management

Manu Biosphere Reserve, Peru

• In SE Peru
• Covers 1.9 million hectares
• Around 6500 Quechua and 2000 Amazonian people are living in the reserve
• World heritage site
• As many as 1000 bird species

Management

• Prohibition of firearms
• Removing cattle to reduce grazing
• Provide equipment and training to local people to reduce burning in the area
• A team provide financial and logistical support for the communities
• Research to understand how to sustainably use the land
• Disease within domestic animals in native communities are monitored
• Promoting ecotourism

Jau National Park, Brazil

• World heritage site
• Largest National Park in the Amazon basin

Management

• Research into and protection of biodiversity
• Park only accessible by river
• Journey from nearest city is between 8 and 18 hours
• Few registered tourist agencies
• Visitors need prior authorisation

Why are rain forests hard to manage?

• Rainforests are usually located in less developed areas meaning that the level of the education and overall awareness of the importance of them is lower.
• Lack of funding in conservation projects.
• Corruption means that policy makers can be swayed by business owners who may benefit more from less conservation.
• Increasing global population mean a higher demand on rainforest projects.
• Difficult to police large areas.

Ecosystems - Tropical rainforest plants and animals

Plant adaptions

• Buttress roots - Rainforest have a shallow layer of fertile soil, so trees only need shallow roots to reach the nutrients. However, shallow roots cannot support huge rainforest trees, so many trees have developed huge buttress roots. These stretch from the ground to two metres or more up the trunk and help the anchor the tree to the ground.
• Drip tips - Plants grow thick leaves with drip tips and waxy surfaces to allow water to drain quickly to prevent mould, bacteria and fungus from growing and destroying the leaf.
• Lianas - They are woody vines that start at ground level, and use trees to climb up to the canopy where they spread from tree to tree to get as much light as possible.
• Strangler figs - They start at the top of a tree and work down. The seed is dropped in a nook at the top of a tree and starts to grow, using the debris collected there as nourishment. Gradually the fig sends aerial roots down the trunk of the host, until they reach the ground and take root. As it matures, the fig will gradually surround the host, criss-cross its roots and start to strangle. The figs branches will grow taller to catch the sunlight and invasive roots rob the host of nutrients. Eventually the host will die and decompose leaving the hollow but sturdy trunk of the strangler fig.
• Bark - Thin, often smooth bark, since trees do not have to deal with cold weather. The smooth bark reduces root holds for epiphytes and allows rapid water run-off.
• Epiphytes - They are plants that live on the surface of other plants, especially the trunk and branches. They grow on trees to take advantage of the sunlight in the canopy.

Animal adaptations

• Chimpanzees - To avoid competition from other monkeys, chimpanzees forage on the ground. Their long arms and flexible joints allow them to swing from tree to tree while in the canopy, avoiding predators. Their ability to climb is helped by their tail which is used for balance and their opposable thumbs allow strong grips onto the branches.
• Tasmanian Pademelons - To retain body heat in cold temperatures, they have round bodies.
• Aye Aye - To escape from predators hunting, they are nocturnal. Its large eyes allow more light in at night and it takes advantage of tall trees to build his daytime nest for concealment out of sight of rainforest floor predators.
• Amazon Horned Frog - It is a small predator, its body acts as camouflage allowing them to lie in piles of dry leaves in order to ambush their prey. They have large mouths and sharp teeth to quickly catch their prey.
• Parasol ant - Found on the forest floor, they are adapted to climb trees up to 100ft tall and cut out small pieces of leaves. They can carry fragments 50 times their body weight back to their homes where they bury it underground and a fungus is produced from the mixture of leaves and substances which the ant can eat.

Ecosystems - Tropical Rainforest

The tropical rainforest is found 5° north and south of the equator. It includes the Amazon and Congo basins and the coastal lands of Ecuador, West Africa and South-East Asia.

It is constantly hot and humid with up to 2500mm of rain a year.

The Gersmehl model of the rainforest

Biomass is largest due to high temperatures, high rainfall and long growing seasons. Rapid absorption from soils means that the rate of photosynthesis is high.

Soil store is small because high rainfall encourages leaching and uptake of nutrients is rapid.

Litter is s small store because high temperatures and moisture levels result in fast decomposition.

Structure

Ecosystems - High Elms case study

High Elms Country Park is a mix of woodland, wildflower meadows, nature conservation and gardens. It can be found in Farnborough, 15 miles away from central London. It is on the greenbelt.

It is home to BEECHE (Bromley Environmental Education Centre at High Elms), which is a sustainable education and visitor centre. It puts on talks and activities for school and teaches children how to look after the environment and the woodland.

It is a SSSI and a local Nature Reserve, enjoying the support of local environmental groups as well as the friends of High Elms, Nature England and the Forestry Commission.

There are chalk meadows and woodlands that support a variety of wildlife including species that are rare in London.

Ecosystems - Ecological conservation area

The Norfolk Broads

• 301 km² of marsh, woodland and open water in Norfolk and Suffolk.
• It is the flooded remains of medieval peat diggings.

Ecological importance:

• 28 SSSIs
• High biodiversity
• Protected grazing marsh
• Ramsar conservation designation
• Biodiversity action plan

Human impact:

• Domestic waste disposal 
• Drainage for grazing
• Growing population 
• Increase in boating
• Intensive farming methods

Management:

• Special areas of conservation
• Preventing deterioration of water systems by reducing pollution
• UK biodiversity action plan 1994
• Farmers given special payments to manage and conserve landscape 

Dulwich Upper Wood

• Aims to provide the local area with increased biodiversity and aesthetically pleasing walks.
• Built upon victorian property remains and ancient woodland.
• 250 fungi types and 40 species of bird.
• Habitats has been recreated or preserved in order to return them to their natural state.
• Trails to reduce trampling.

Ecosystems - Effects of urbanisation on ecosystems

How urbanisation creates ecosystems

• In between train lines 

 - No human activity
 - 2.5 million trees are around tracks in the UK

• Industrial sites

 - e.g. Battersea Power station
 - Peregrine falcons, black redstarts, bats and linnets can be found

• Urban gardens

 - 20% of London is gardens
 - Encourages more animals like bees

• Allotments

 - e.g. Southland road, Bromley
 - growing fruit and veg attracts toads, rabbits and hedgehogs

• Urban forests

 - e.g. Petts Wood, London
 - conservation work allows more species to be protected


Urban niches

Within an ecosystem all living organisms occupy a niche. Their niche is the place where they live (their habitat) and how they interact with other species (their role).

Human use means urban ecosystems are subject to more change and at a faster pace than other ecosystems.
Change such as drainage, composition of surface material, introduction of new species.

An example is the Kestrel, which likes to live in cities like London due to high rise buildings.

Colonisation of wasteland

The colonisation of most wastelands is a lithosphere type succession.

1. Lichens and mosses grow in cracks with moisture and nutrients.
2. A thin layer of soil is produced and herbs start to grow.
3. As the soil layer gets thicker taller grasses grow.
4. Next are small trees and shrubs like Buddleia.
5. Over many years this is replaced by scrub woodland.


Routeways

• In London, plane trees are commonly planted by the sides of roads as they are well adapted to urban environments.
• By roads, nitrogen rich exhaust fumes boost the growth of some wild flowers.
• Railways enable species to move around cities and through the country.
• Soil verges by motorways make a good seedbed for seeding due to chemicals from agricultural run off.
• Canals allows aquatic plants like the Yellow flag iris to spread along the canal system.
• The M4 corridor is home to Kestrels as they scavenge for road kill.
• Along train lines, tracks are fenced off so there is little human interference.
• Canals attract water loving insects like dragonflies.

Invasive species

An invasive species is a plant or an animal not native to an area.

e.g. Oxford ragwort

• Brought to Oxford from Sicily for research in a botanic garden.
• Seeds are air bound so can travel in the air for long distances.
• This allowed them to get on trains and travel along the rail network.
• This then allowed it to spread across the country.

Ecosystems - Heather moorlands

A heather moorland is a plagioclimax so human influences prevent the ecosystem from reaching a climatic climax.

Case study: Rannoch Moor, Scotland

The woodland was first cleared out to allow crops to be grown and to provide space for grazing. But once the trees were removed there were no deep roots to bring the nutrients to the surface and renew the soil fertility. Instead the heavy rainfall, which would be intercepted by the trees, was able to leach the nutrients out of the soils. So the upland areas were often colonised by bracken, grasses, shrubs and heather.

Management:

• Heather is burnt every 3-4 years to make young shoots grow so there can be food for Red Grouse, which can be shot for sport.
• Burning also prevents the regrowing of forests so sheep and cattle can continue to graze.
• In small areas people are trying to bring the forest back by fencing it off to reduce grazing and trees are being planted.

Ecosystems - Temperate deciduous woodland

General facts:

- These forests require a climate which has a growth period of 4-6 months and a cool but mild winter when their shed. Rain occurs all year round with between 500-1500mm.

- There are 4 layers of vegetation: canopy, shrub, field and ground

- Some woodlands are dominated by one species e.g. oak or beech

- The types of shrubs found vary with light available like the Indian Pipe flower can survive on the forest floor with little light.

- There are relatively few species of dominance.

- It has high net primary productivity during the growing season.


Management:

Hayley Wood, Cambridgeshire

•  Part of the woods are fenced off by the Wildlife Trust in order to protect it from deer browsing.

•  Living Landscape schemes create spaces for animals to move between places in order wild flower seeds to be able to settle and grow.

•  Cut and Chew project aims to conserve grassland by using traditional grazing.

New Forest, South England

• Low levels of management to maintain traditional feel.
• Removal of exotic species and appropriate placement of native species.
• Fences put up to reduce grazing.
• Small timber usage.

Ecosystems - Wider reading

If you need to do any wider reading for the course, here are some useful articles:

http://www.naturalnews.com/049099_Amazon_river_rainforest_dust.html#

http://www.naturalnews.com/032313_tortoises_ecosystem.html

http://www.enn.com/ecosystems/article/49196

http://discovermagazine.com/2013/september/16-deep-sea-secrets

http://discovermagazine.com/2011/apr/21-mangrove-tree-captures-carbon-filters-saltwater-stops-storms

http://zeenews.india.com/news/eco-news/bad-tree-planting-can-harm-biodiversity_1759130.html

http://www.sciencedaily.com/releases/2016/02/160225153614.htm

http://www.sciencedaily.com/releases/2016/02/160224145556.htm

http://planetearth.nerc.ac.uk/blogs/post.aspx?id=641&pid=193&cookieConsent=A

Ecosystems - Succession and climatic climax in a hydrosere

e.g Sweet Mare, Shropshire

1. Lakes and ponds originate as clear water, which contains few plant nutrients.

2. The earliest colonisers will probably be algae and mosses whose spores have been blown onto the water surface by wind.

3. These grow to form vegetation rafts which provide a habitat for bacteria and insects.

4. Next will be these water loving species or this totally submerged.

5. Bacteria recycles the nutrients from the pioneer community and marsh plants, such as bulrushes, sedges, and reeds, begin to enroach the lake.

6. As these marsh plants grow outwards into the lake further sediment builds upwards at the expense of the water. Small trees will take root forming a marshy thicket.

7. In time, the lake is likely to contract in size to become deoxygenated by the decaying vegetation and eventually disappear and be replaced by the oak climax vegetation.

Ecosystems - Gersmehl's model

Gersmehl's model shows the transfer of nutrients between stores in the nutrient cycle.

The circles are proportionate to the amount of nutrient stored and the arrows width are proportional to the nutrient flow.

In a rainforest ecosystem, the largest store is biomass and it has the highest rate of transfer due to the warm, moist conditions.

In a deciduous forest ecosystem, the largest store is soil.

Ecosystems - All the definitions

Ecosystems - combination of plants and animals living together with the non-living environment.

Photosynthesis - the process in which carbon dioxide and water are made into glucose and oxygen by plants.

Gross primary productivity - the rate of energy conversion into sugars by photosynthesis.

Biomass - energy which is stored as plant material.

Net primary productivity - the rate of photosynthesis minus the rate of respiration.

Net secondary productivity - the rate of biomass production by a herbivore.

Herbivore - plant eaters that get their energy directly or indirectly from plants.

Carnivores - these are meat eaters that gain their energy by eating herbivores.

Food chain - the movement of energy from sunlight to plant to herbivore to carnivore.

Trophic level - each step in a food chain.

Ecological community - a group of interacting species living in the same space and bound together by the influences that the species have on one another.

Abiotic - the non-living things in an ecosystem.

Biotic - the living environment.

Trophic pyramid - a pyramid diagram showing the four main thophic levels.

Autotrophs/producers - first and lowest level in a trophic pyramid.

Detritivore - an animal that feeds on dead material or waste products.

Starting out

I'm gonna try and post all of my geography notes on here as a type of revision. Feel free to add more information in the comments. This follows the AQA syllabus. For them to be in order by topic, click on the tags.