IB ESS case studies
Unit 2: Four contrasting biomes
Tropical rainforests are found closer to the equator where it is warm (eg. Southern Chile or New Zealand) Temperate rainforests are found near the cooler coastal areas further north or south of the equator (eg. North America, eastern Asia, and Europe. Tundra has snow-covered lands and it is an extremely cold ecosystem (Alaska) Desert has sandy lands and it is an extremely dry and hot ecosystem (Sahara) The tropical coral reef (eg. Australia) is one of the most productive ecosystems on Earth, providing important services to mankind including fisheries, coastal protection, medicines, recreation, and tourism. Temperate grasslands (eg. the steppe in Eurasia, the prairies of North America, the downs of Australia) have cold winters and warm summers with some rain. A few trees but not many due to the lack of rainfall. Savanna is a vegetation type that grows under hot, seasonally dry climatic conditions and is characterized by an open tree canopy (i.e., scattered trees) above a continuous tall grass understory (eg. Southern Africa) Taiga is a thick forest. Coniferous trees, such as spruce, pine, and fir, are common. (eg. Alaska, Canada, Scandinavia, and Siberia)
Unit 7: carbon dioxide removal techniques
UN-REDD - Reducing Emissions from Deforestation and forest Degradation", conservation of forest carbon stocks, sustainable management of forests, and enhancement of forest carbon stocks in developing countries. Biomass - a range of processes that use plants and algae to remove carbon dioxide (CO2) from the atmosphere and store that CO2 underground or in long-lived products. CSS - the capture of carbon dioxide (CO2) emissions from industrial processes, such as steel and cement production, or from the burning of fossil fuels in power generation. This carbon is then transported from where it was produced, via ship or in a pipeline, and stored deep underground in geological formations.
Unit 6: detailed study evaluating role of national and international organizations in reducing the emissions of ozone-depleting substances
UNEP (United Nations Environment Programme): - forges international agreements - studies the effectiveness and difficulties of these agreements to implement and enforce them. - Brought together 46 countries in 1987 to sign the initial Montreal Protocol on the Substances that Deplete the Ozone Layer The Montreal Protocol (1987): an international agreement on reduction of emission of ozone-depleting substances. - The signatories agreed to freeze production of many CFCs and to strongly reduce consumption and production of these substances by 2000. - Most countries followed the rules but China and India continued to produce and use huge amounts of CFCs. significance: 1. Best example of international cooperation on an environmental issue by altering human activities. 2. Experts from many different fields coming together to research a problem and find solutions. 3. The first to recognise that different countries could phase-out ODS chemicals at different times depending on their economic status.
Unit 5: two studies of contrasting FPS -terrestrial
comparing inputs, outputs, system characteristics, environmental impacts, and socio-cultural systems such as industrial beef farming vs. traditional Maasai livestock
Unit 1: Understanding of the Millennium Ecosystem Assessment and its Findings
concept of MEA: - Initiated in 2001 an international work program designed to meet the needs of decision makers and the public for scientific information concerning the consequences of ecosystem change for human well-being and options for responding to those changes. - to assess the consequences of ecosystem change for human well-being and the scientific basis for action needed to enhance the conservation and sustainable use of those systems and their contribution to human well-being. general findings: - generally successful - humans have vastly changed the ecosystem in the past 50 years to meet food, water, timber, fiber and fuel demands resulting in irreversible loss. - diminishing benefits that future generations can obtain from the ecosystem. - To conserve or enhance specific ecosystem services in ways that reduce negative trade-offs or that provide positive synergies with other ecosystem services. - Human actions are depleting Earth's natural capital, straining the environment that the ability of the planet's ecosystems to sustain future generations can no longer be taken for granted.
Unit 1: Evaluate a named historical event that lead to the banning of DTT.
in 1970 WHO banned DDT - banned in 1972 in USA - but it is still used in some countries in small quantities. Did banning DDT does more harm than good: malaria kills 2.7 mil ppl yearly (mostly children < 5), said that DDT prevents millions of malaria deaths. DDT is sprayed on furniture - persistent use causes resistance in malaria mosquitos Rachel Carson: Silent Spring - 1962: discusses the effect of DDT on birds of prey, thinning eggshells and reducing population. Shows the impacts of DTT on the environment and human health Leading to the ban of DTT by World Agriculture in 2001 Pros: - reduce/stop biomagnification of DDT - improvement in child's development - reduce cancer, asthma, pregnancy loss - the environmental system can recover Cons: - Malaria risk increases; more death - Fewer effective alternative for DDT - Alternative pesticides are more expensive - Natural selection in resistance - Research doesn't receive enough funding (bias and misinformation)
Unit 1: (1 - dust bowl) People or events who were important to the development of environmental awareness
• 1930s North America midwest (Kansas, Texas, and Oklahoma) • 10-year-long drought • began as people came to ploughing land that wasn't good for farming not knowing the effects. • before the civil war: everything was dry, and no one stayed there, was named "The Great American Desert" • 1880: lots of rain so plains are better for farming, people believed farming and industrializing with electricity would cause more rain to fall. • 1890: short drought but more rain • 1930: drought returned and stayed for 10 years so no crops could survive such as wheat, not keeping the soil in place. • farms into deserts with blowing sand with dust storms • Massive loss of topsoil due to overgrazing and intensive ploughing of prairies • Spurred new agricultural techniques and soil conservation service
Unit 1: (2 - Gaia Hypothesis) People or events who were important to the development of environmental awareness G
• Late 1970s • James Lovelock states that Earth is a synergistic, self-regulating system • Planet functions as an organism having a homeostatic mechanism which regulates conditions on the planet. • Useful when thinking about the Earth as a system and particularly in view of the global changes occurring today.
Unit 8: Anti-natalist population policy case study
CHINA ONE CHILD POLICY - Slowed the birth rate by a lot - This was encouraged rather forcefully by the Chinese government, forcing women to have abortions if they already had a child. - However, there were financial benefits for families who kept to the one-child policy. - This was implemented to control the rapidly growing Chinese population.
Unit 2: compare and contrast r and k strategists
r strategist is the organism living in unstable environments. Therefore, r strategist reproduces fast in order to ensure its survival. dogs, cats, insects, and fish K strategist lives in stable, predictable environments hence much more stable and does not require rapid reproduction rates. Elephants, humans, lions or whales.
Unit 4: detailed study of unsustainable fishing and associated fishery management strategies
- Bluefin tuna populations have declined severely from overfishing and illegal fishing over the past few decades - Demand in sushi markets give around $1 billion AUSD per year - Breeding takes place from September to April in the warm waters off the south of Java, Indonesia. Fully grown fish are spread out along the southern hemisphere and are rarely seen near coasts while younger fish are. - The Southern Bluefin tuna is listed as critically endangered and although the fishery is tightly controlled, the fish is still caught in huge numbers every year and is overfished. - Because of its reproductive cycle, it lives for around 20-40+ years and reaches sexual maturity after around 10 years. - Most fish are caught and sold at around age 4 or 5 as they are easier to catch - This is extremely unsustainable as it means fish are being taken from the stock faster than the stock can replenish itself.
Unit 7: Mitigation and adaptation strategies in Singapore
1. Building up public transport - Start-up losses as the system take some time to gain ridership. - Can be inconvenient for a certain lifestyle - Doesn't take you door to door - Overcrowding during peak hour-> make the riding experience less pleasant +Extensive- has routes around Singapore +Cheap - ranging from $0.67 to $1.72. 2. Heavy taxation on cars - COE - harder for people to get to their jobs - Decreases the demand for cars but wastes resources. - People use cab services instead of public transport. +Increases the prices of cars = less demand for cars -> Fewer cars on the road + More public transportation is used + More people walking or riding bikes rather than using cars 4. Electricity from solid waste - Expensive. - It could release steam. Eg: Tuas Incineration Plant $890 Million - Low electricity generation, Eg: Semakau Landfill until 2035. +The waste remaining is incinerated and used steam to generate electricity. + Reduce 90% of waste volume. Over the long term, this has helped Singapore to reduce its need for future landfills. 5. Signed the Kyoto Protocol in 2006 & Paris Agreement in 2015 - Tough policy to learn and implement - Alternative technology has not advanced far enough - Decrease in GDP and great loss of jobs in developed countries. +Committed to monitor CO2 emissions + Provides the foundation for innovation + Thinking of the welfare of future children + Consequences for companies who pollute
Unit 4: a detailed study of how shared freshwater resources have given rise to international conflict
1. Middle East Water shortage: - Area contains only 0.5% of the world's freshwater supply and 5% of the world's population. - Major drought in 2008 in Israel. Forced to stop pumping from the Sea of Galilee and draw from aquifers instead. - Did not restrict water supply to its neighbour Jordan. - Israel has two desalination plants that supply one-third of used water for households.
Unit 4: 1. Freshwater pollution example 2. marine pollution example 3. process and impacts of eutrophication
1. Middle East Water shortage: - Area contains only 0.5% of the world's freshwater supply and 5% of the world's population. - Major drought in 2008 in Israel. Forced to stop pumping from the Sea of Galilee and draw from aquifers instead. - Did not restrict water supply to its neighbour Jordan. - Israel has two desalination plants that supply one-third of used water for households. 2. Great barrier reef pollution including Marine debris pollution - Plastic pollution - Ocean acidification - Nutrient pollution - Toxicants - Underwater noise 3. lake Erie eutrophication - supplies drinking water to 11 million people, and is home to numerous aquatic species. - During 18th and 19th centuries, people dumped everything into the waterway causing pollution up until 20th century until people were aware of the importance of clean water for health
Unit 8: 1. Renewable source case study 2. Non-renewable source case study
1. Netherlands: In 2022, around 40% of the electricity consumed in the Netherlands came from renewable sources. Renewable electricity production was up 20% compared to the year before. Production from fossil sources fell by 11%. Most of the growth in renewable energy production came from solar. 2. Beijing: most industrious city of its nation and most polluted due to non-renewable sources of energy - coal being the most used resource - Takes years to form - Economic: countries made a lot of money from distributing coal - Provided jobs - Environmental: unsustainable and harmful emissions - Tech can create better sources of energy - Political: agreements to decrease coal use
Unit 8: 4 types of ecosystem services
1. Supporting - essential for life: photosynthesis, water cycle 2. regulating - carbon storage 3. Provisioning - wood, fuel, water, food 4. Cultural - outdoor recreation areas that improve human health examples: Wetlands: water purification, store carbon, fish stocks, habitats for organisms that impact recreation
Unit 8: Pros and cons of types of solid domestic waste disposal options
1. landfills - Pros: Easy to construct, straightforward concept, cheap, good for non-recyclable waste and less GHG emissions compared to burning trash. - Cons: Air, Soil and water pollution, destruction of natural habitats and deforestation 2. incinerators Pros: Reduce trash volume, produces energy, and less space needed Cons: Expensive, produces hazardous waste and Air pollution 3. composting Pros: Improves soil quality. and structure, higher yield, less waste and eco-friendly Cons: Initial investment, the unpleasant smell may attract rodents and insects and needs monitoring
Unit 2: Zonation case study
A lower alpine zone with bush and tall herb communities - Compared with oceanic Scotland the vigorous and widespread mountain willow zone on exposed mountainsides - luxurious tall herb communities in more sheltered areas in Scandinavia is very striking. - This is especially so as attempts to restore the willow communities on Scotland's most species-rich mountain, Ben Lawers (1214 m, 3983 feet), have had very limited success.
Unit 7: Two detailed examples of contrasting viewpoints on climate change
Al Gore - was one of the first politicians to grasp the seriousness of climate change and to call for a reduction in emissions of carbon dioxide and other greenhouse gases The stern report is a landmark study that was released on 30 October 2006 by Her Majesty's Treasury of the UK Government.
Unit 3: Conflict between exploitation, sustainable development and conservation
CAMPFIRE initiative in Zimbabwe In 1975 ownership of wildlife went from the state to the communal property of people leaving the land not being used for agriculture, open for unmanaged wildlife. first community-based wildlife conservation project to approach wildlife as a renewable, profitable resource USAID started to fund the Communal Areas Management Programme for Indigenous Resources to make residence encourage tourism to the region and by providing funds for wildlife ecology research. enabling hunters to pay an extensive fee to be allowed to kill one large game animal, most often an elephant. while some organisms would be killed, the longevity of these species would be secured by the funds received, as the hunted meat and profits would be given to the local communities for the development of schools, clinics, and wildlife research facilities.
Unit 5: Difference between industrial and subsistence farming systems
California, United States commercial rice farming: methods imposed mostly by the Soil and Conservation Act of 1935. - Contour ploughing - Strip cultivation with an alternation of cultivated and fallow (crop-free) land aligned across the direction of the prevailing wind. - Temporary cover crops such as fast-growing millet - Shallow ploughing to eliminate weeds and conserve crop residues on the surface. - Use of heavy machinery; high input of energy and chemicals; lower energy efficiency - High productivity; output includes pollution Borneo, Indonesia Subsistence farming: - Sustainable form of agroforestry - Traditional extensive - Labour-intensive - Polyculture - Maintains soil quality by working with nature - Lower productivity - higher energy efficiency - rice is the only output
Unit 2: one detailed example of how human activities impact energy flows and matter cycling
Deforestation: - long-term stores of nitrogen, carbon and sulphur are released into atmosphere. - causes biodiversity loss, leaching, global warming and acid rain. Amazon Rainforest: - 50-80% of the moisture in the central and western Amazon remains in the ecosystem water cycle. - Moisture is evaporated into the atmosphere, forming rain clouds before being precipitated as rain back onto the forest. - When the forests are cut down, less moisture is evapotranspired into the atmosphere resulting in the formation of fewer rain clouds. - Subsequently there is a decline in rainfall, subjecting the area to drought. - If rains stop falling, within a few years the area can become arid with the strong tropical sun baking down on the scrubland. Other examples: - The declining rainfall in West African countries has in part been attributed to excessive clearing of the coastal rainforests. - Australia suggests that if it were not for human influences the dry outback might be a wetter, more hospitable place than it is today. - Colombia, once second in the world with freshwater reserves, has fallen to 24th due to its extensive deforestation over the past 30 years. - Malaysia, Kuala Lumpur experiencing excessive deforestation combined with the dry conditions created by el Niño, triggered strict water rationing in 1998, and for the first time the city had to import water.
Unit 7: energy security and stategies of sweden
Denmark --> The main goal of the Danish 2050 Energy Strategy is to achieve 100% independence from fossil fuel in the national energy mix by 2050 In a first step to completely phase out fossil fuels the government targets a drop in the consumption of oil, gas and coal by 33% between 2009 and 2020
Unit 2: Detailed description of contrasting biomes
Desert Biome: - 20-30% of the world's surface - Dry, hot and little vegetation - Example: Atacama Desert in Chile it did not rain for 20 years - Soils are nutrient-rich as they can't be washed away - Reptiles are dominant and plants are drought resistant (Ccacti and Succulents) - Small mammals adapt to be nocturnal and many other things Limiting Factors: >250mm of precipitation & evo>precipitation Net productivity: primary & secondary are low because of limited resources Animals: - Arabian camel (middle east, Africa, India and Pakistan) stores fat in humps to last 3-4 days without food or water. - Bilbi (Australia) is an endangered, nocturnal (underground during the day and hunting for food at night) diet containing snails, fice and insects. Temperate grassland - Flat area dominated by grasses and herbaceous plants - centres of continents 40-60 north of the equator - not a climax community - carnivores (wolves, coyotes. no trees) and Burrowing animals (rabbits, gophers), kangaroos, bison, antelopes - Used for cereal crops - Dust bowl in 1930s in America when overcropping and drought led to soil being blown away Net productivity: not very high (600) climate: - Precipitation same at evaporation - Temperature range is high - clear skies low rainfall, threat to drought examples: - North American prairies - Russian steppes - Pampas in Argentina
Unit 3: Conservation case studies of Extinct
Dodo: large flightless birds endemic to the island of Mauritius, extinct by 1681 Ecological role: ground-nesting bird (couldn't fly) and helped to germinate seeds of the Dodo trees. Pressures: - in 1505, Portuguese sailors ate dodos as a source of fresh meat - new species (rats, monkeys) introduced that ate dodo - humans killed the birds for sport - the destruction of habitat by the human population The consequence of disappearance: - Island fauna impoverished - became an icon due to its apparent stupidity ( no fear of humankind)
Fundamental niche vs. realized niche Named species for each of the following: 1. Predation 2. herbivory 3. parasitism 4. mutualism 5. disease 6. interspecific competition 7. intraspecific competition
Fundamental niche: All possible conditions under which an organism can survive and reproduce. Realized niche: Actual conditions used by a given organism, after interactions with other species (predation and especially competition) have been considered. 1. Predation - owls hunting mice 2. herbivory - Koala and eucalyptus leaves 3. parasitism - lice (Pediculus humanus capitis) on a humans head 4. mutualism - Aphids and ants 5. disease - malaria or influenza 6. interspecific competition - cheetahs and lions 7. intraspecific competition - two oak trees
Unit 3: Conservation case studies of Conservation status improved by intervention
Golden lion tamarin: Small rare monkey endemic to Atlantic coastal rainforests in Brazil, 1000 in the wild, 500 in captivity Ecological role: Omnivore and prey to large cats and birds of prey. Live in family groups in the wild tropical rainforest. Pressures: - Only 2% of native habitat is left - Poaching can get $20000 per skin - Predation is great in the wild and the food sources are not dependable Method of restoring populations: - over 150 institutions for captive breeding programmes and exchange individuals for increased genetic diversity - long-term future not known yet as survival in wild is low
Unit 3: Threats to biodiversity from human activity in a given natural area of biological significance or conservation area
Great Barrier Reef Marine park (1975) - Extends south from the tip of north Queensland, in north-eastern Australia, to just north of Bundaberg. - 60 and 250km in width, average 35m in depth on inshore waters - The outer reefs extend to depths of over 2,000m Threats: - Coral Bleaching --> Because of global warming caused by mining and burning fossil fuels, heating the oceans - Farm pollution --> Smothers corals and seagrass beds and denies them sunlight, making coral vulnerable to bleaching. --> Nitrogen run-off from farms can also lead to algal blooms which starfish larvae feed on, promoting population explosions - Governance --> The reef needs a stronger champion to defend it from overfishing and a multitude of other threats. - Industrialisation --> Plans to expand several ports along this coastline leading to dredging of the seafloor, increased shipping traffic, and a range of other impacts on the delicate coastal and marine environment. - Poor management of commercial, recreational and indigenous fishing --> Increasing threats to many of Queensland's threatened species (Dugongs, turtles, and inshore dolphins)
Unit 1: Natural capital: Replenishable
Groundwater and the ozone layer, is nonliving but is also often dependent on the solar "engine" for renewal.
Unit 3: success of protected area
Khabr National park in Iran Ecologically, the vertical and horizontal structures and different functions of plant communities were investigated using different criteria. Socially, acceptance of the protected area was assessed through interviews and questionnaires. The protected area was successful in restoration of ecosystem structure, especially at 0−1 m height class
Unit 7: International efforts to address climate change
Kyoto Protocol: operationalizes the United Nations Framework Convention on Climate Change by committing industrialized countries and economies in transition to limit and reduce greenhouse gas (GHG) emissions in accordance with agreed individual targets. The Paris Agreement: the commitment to reduce greenhouse gas emissions by at least 40% by 2030 compared to 1990, under its wider 2030 climate and energy framework the IPCC: Intergovernmental Panel on Climate Change. The IPCC is the scientific group assembled by the United Nations to monitor and assess all global science related to climate change. Every IPCC report focuses on different aspects of climate change.
Unit 7: Two examples of Impacts of climate change in different countries
Netherlands: - The relatively long coastline, combined with the fact that about a third of the country is situated below sea level, makes the Netherlands vulnerable to sea level rise. - Consist of lowlands in a delta, it is vulnerable to flooding from rivers. - Increased frequency of droughts and heatwaves - gastrointestinal illness like diarrhoea, effects on the body's nervous and respiratory systems, or liver and kidney damage. Dubai UAE: The continuing temperature rise caused by global warming contributes to UAE's water scarcity, drought, rising sea levels, and aridity. The countryside of the UAE, characterized by its great arid land, infrequent precipitation, and high temperatures are already facing long-term aridity.
Unit 1: Brief example of types of natural capital: Non-Renewable
Non-renewable natural capital: fossil fuels, minerals and metals Case study: Mismanagement of Oil Fossil Fuels / Deepwater Horizon Disaster What: Largest oil spill in US history in an ultra-deepwater offshore drilling rig. What happened? - April 2010: explosion ripped through the Deepwater Horizon oil rig in the Gulf of Mexico. - 2 days later, the rig sank with oil pouring out into the sea at a rate of up to 62,000 barrels a day at its peak. Consequences: - Threatened wildlife along the US coasts - threatened livelihoods dependent on tourism and fishing - 160 km of coastline was affected - Severe environmental impact lasting a long time - Cost to BP, who operated the rig, may reach $20b - about 4.9 million barrels of crude oil released into ocean. What was done: Dispersants were used to break up the oil slick but BP was ordered by the US government to limit their use, as they could cause even more damage to marine life in the Gulf of Mexico
Unit 1: Origin, uses and Consequences of DDT for Ecosystems and human systems
Origin: - developed as the first of the modern synthetic insecticides in the 1940s. uses: - combat malaria, typhus, and the other insect-borne human diseases among both military and civilian populations. - insect control in crop and livestock production, institutions, homes, and gardens. (pesticide) Pros: - Relatively cheap - Highly persistent so that it continues for months after application to kill insects such as mosquitoes that carry disease - Used to virtually eliminate malaria dengue fever and filariasis - Estimated to have saved about 50 million human lives and to have prevented more than a thousand million human illnesses Cons: - kills all insects that come in contact with it. - thinning birds' eggshells; reducing their population numbers - it is persistent -> fall into the food chain => bioaccumulate and biomagnified - affect the development of children e.g in Yaqui Valley, Mexico - broad use in the United States and other countries led to the development of resistance by many insect pest species.
Unit 8: examples of ecological footprints in one named HIC and one named LIC and reasoning for why they differ.
PERU - 0.9ha/person - fast growing trees (high NPP), largely vegetarian diet, low car ownership, warm all year round, poor population. CANADA - 5.4ha/person - low productivity from trees as located in high latitudes, large distances to cover by car, wealthy population, heating needed in cold winters and electricity in winter for dark evenin
Unit 1: (3 - Silent spring) People or events who were important to the development of environmental awareness
Rachel Carson: Silent Spring - 1962: discusses the effect of DDT on birds of prey, thinning eggshells and reducing population. •Showed the link between pesticides and ecosystem health •Raised awareness of pesticides of the United States •Resulted in the banning of DDT
Unit 3: Conservation case studies of Critically endangered
Rafflesia: Tropical parasitic plant in jungles of SE Asia (15-19 species) Ecological role: - Single-sexed - Pollination carried out when in bloom. - Both genders in the same area are ready for pollination at the same time. - Seeds dispersed by small squirrels & must reach a 'host' vine Pressures: - Need very specific living conditions to survive - Vulnerable because of deforestation and logging - Damage by humans, less flowers, less reproduction Method of restoring populations: - Sabah, Sumatra and Sarawak there are sanctuaries - Education and monitoring campaigns/programmes
Unit 3: Causes of the 5 major extinctions
Rapid changes in climate, changes in the composition of environments on land or in the ocean (such as ocean acidification or acid rain from intense volcanic activity)
Unit 1: Brief example of types of natural capital: Renewable
Renewable natural capital: water, solar and wind energy Case study: Mismanagement of renewable natural capital = Fresh Water dams on the Mekong River Advantages: Laotian Dam will create a 60-kilometre long reservoir - generate 1260 megawatts of power - earn between $3-4 billion a year - The village of Pak Lan in Laos will have roads and electricity, as well as reservoir teeming with fish. Disadvantages: - dams in China and in the upper Mekong will block about half of the river's sediment --> disastrous for the delta; - Damming the Mekong River could harm millions who rely on migratory fish, such as the fishermen in this floating village in Kandal, Cambodia; - It will shake sustainability of the fish flow; - Water level shifting destroyed dry season crops such as chillies, vegetables and others. -Species will be affected along the river (the Pink River Dolphin). There are at least 139 fish species that would be blocked from swimming past the Xyanburi dam.
Unit 8: HIC and LIC at each stage of demographic transition model
STAGE 1: high death and birth rates, low life expectancies (Amazon, Brazil and rural communities of Bangladesh) STAGE 2: early expanding, birth rates high and death rates rapidly decreasing, so high population increase, slightly higher life expectancy (Afghanistan and Sudan) STAGE 3: late expanding stage, birth decreasing and death rates are slowly decreasing, family planning and education (Mexico, India, Colombia, and South Africa) STAGE 4: birth rates slowing down, death rates stable, population is high but not increasing (UK, USA, HICs) STAGE 5: declining stage, birth rate decreasing, death rate increasing, population decreasing, high life expectancies (Japan and Sweden)
Unit 4: a detailed study of controversial harvesting
Salmon farming in British Columbia, Canada - overfishing in the sea -> not enough salmon to meet the damands - salmon farms increase; causing pollution 1 . chemicals used in the farm to kill lices are toxic; fishes in the surrounding area have high level of tumours lesions and I-parasite 2 . Food web is affected 3. . When drug loss efficiency -> lices may become stronger-> affect wild salmon population 4. Genetically modified farmed-fishes escape into the wild; interbreed with wildfish -> reduce their ability to survive 5. high density of fishes in the farm; organic wastes enter the ocean and pollute the water. Solutions - move the salmon farm to a close-containment system technology - consumers can choose to buy wild salmon instead of the farmed one; putting pressure on the farm to make changes
Unit 2: Case Study of secondary succession
Secondary succession and resource use in Coromandel Coast of South India - Agricultural fallows, village commons and degraded forests, are considered as 'wastelands', having little economic value and poor biodiversity. - four sites aged 2, 4, 10 and 50 years were used to investigate change in species composition and abundance, convergence with a nearby forest and to examine their economic use. - Presence of adults of five primary forest species found in the clumps indicates a fast rate of secondary succession, considering that grazing and resource removal occurred in the sites. - The potential value of the 'wastelands' is evident from the fact that 64 per cent of recorded species have economic use, which underlines the need for their sustainable utilization for better management of bioresources rather than converting them into monocultures.
Unit 4: detailed study of impacts of aquaculture
Shrimp farming in Thailand - aquaculture grew dramatically during the 1980s. - 1985: annual production was estimated to be about 10,000 tonnes and by 2009 had increased to around 539,000 tonnes. - 1990: international pressure for Thailand to reduce environmental degradation and produce shrimps more sustainably. Shrimp farming contributes to food security and the economy, with over a million people employed in the industry. Thailand is a key exporter of shrimp to countries such as the USA and Japan. Environmental impacts: loss of mangrove ecosystems (which was breeding area and habitat for many species, protected from coastal erosion, flooding and storm damage.) Approximately two-thirds of the mangrove forests in Thailand have been destroyed as a result of shrimp farming activity. - High-density farming --> rapid transmission of diseases (early mortality syndrome or Yellowhead disease) - The shrimp ponds can accumulate waste products from uneaten food and faeces. - The subsequent biodegradation of this organic waste can lead to anoxic waters.
Unit 8: pro-natalist population policy case study
Singapore pushed a campaign in 1988 offering 12 weeks maternity leave for mothers of 4+ children, posters and slogans - 'have 3 or more!', and offered larger and larger child benefits for each child a family had. - This was due to a fall in birth rate due to men and women deciding not to have families, and pursue careers instead.
Unit 2: Case Study of primary succession
Succession on sand dunes: Studland Bay (southern coast of England in Dorset) - Sand dunes begin with bare surface of sand - Pioneer plants colonize this sant (low growing-fleshy leaves - able to survive temporarily being submersed) - Then Marram grass becomes predominant on the seaward side (waxy leaves fold for less surface area and to reduce transpiration) - Humus developed sandy soil - More pasture bushes and grasses leading to species such as Hawthorn, Elder, Brambles and sea buckthorn being present - Oldest dunes will start growing first pine and eventually oak - Reaches climatic climax vegetation for the area - Final stage: dynamic equilibrium - In the Uk, this is temperate deciduous forest - As succession develops more Humus, nutritional soil, soil depth and more is developed
Unit 4: detailed example of human influence on the hydrological cycle
The Colorado River and agriculture - Chronic overuse of water resources and a historic drought. - The dry period has lasted more than two decades - Spurred by a warming climate primarily due to humans burning fossil fuels.