Case studies

1.1

Task

Evaluate the implications of 2 contrasting EVSs in the context of given environmental issues

Ecocentrism (Yanomami indigenous people)

• living in the Amazon rainforest, valuing nature intrinsically and striving to live in harmony with their environment

• oppose deforestation and illegal mining

• their perspective aligns with deep ecology which emphasizes the rights of ecosystems and species independent of human benefit

Anthropocentrism (Brazilian government policies under Bolsonaro)

• prioritized economic growth over environmental protection

• policies favored deforestation for cattle ranching, soy production, and mining, arguing that economic benefits and job creation justified environmental degradation

• treats nature as a resource to be managed for human use rather than intrinsic value

Technocentrism (Carbon Capture and Storage (CSS) project in Norway)

• to reduce greenhouse gas emissions while maintaining industrial growth

• aims to capture CO2 emissions from industrial sites, transport them via pipeline, and store them permanently under the North Sea

• collaboration between Norwegian government and private companies like Equinor, Shell, and TotalEnergies

2.4

Biomes task

Students should be encouraged to study at least 4 contrasting pairs of biomes of interest to them, such as temperate forests and tropical seasonal forests; or tundras and deserts; or tropical coral reefs and hydrothermalvents; or temperate bogs and tropical mangrove forests.

temperate forests

• temperate forests are found in the temperate zone, between tropical and polar regions

  • mostly found in the northern hemisphere

• they are the 2nd largest forest biome on earth (around 25% of forests)

Examples of temperate forests

• Rocky Mountain Parks (Canada)

• Yellowstone Park (USA)

Climate

• these forests are found in areas that range from 0℃ to 20℃

• the forests are warm in the summer, cool in fall, and cold in the winter

Ecological impacts/significance

• hotspot for biodiversity

  • temperate forests support a wide range of plants and animal species

  • they provide crucial habitats for various species, including mammals, birds, reptiles, amphibians, and insects

• carbon sinks

  • this forest acts as a carbon sink, due to its ability to store large amounts of atmospheric CO2, which helps mitigate climate change

• water cycle/precipitation

  • they play a role in regulating global temperatures and influencing precipitation patters

  • forests regulate water flow, prevent soil erosion, purify water, contributing to the overall health of the water cycle

Abiotic factors

• water

• temperatures

• soil

  • due to the high levels of nutrients, it helps keep the acidity levels of the soil high

Threats to temperate forests

• deforestation

  • logging and urbanization can lead to deforestation and habitat loss

• climate change

  • changing climate patterns, including increased temperatures and altered precipitation, can negatively impact temperate forests

• invasive species

  • introducing non-native species can disrupt the balance of the forest, as this species may overpower the native species

Species

• pioneer

  • trees

    • aspen

    • birch

    • alder

    • willow

  • non-woody plants

    • grass

    • wildflowers

  • nitrogen-fixing pioneers

    • alders

• intermediate

  • plants

    • canopy layer

      • oaks

      • maples

      • beeches

      • birch

    • sub-canopy

      • shrubs

  • animals

    • mammals

      • raccoons

      • squirrels

      • chipmunks

      • deer

      • bears

    • birds

      • robins

      • jays

      • woodpeckers

    • insects

      • spiders

• climax

  • sugar maple

  • beech

  • yellow birch

tropical seasonal forests

• Seasonal tropical forest, also known as moist deciduous, semi-evergreen seasonal, tropical mixed or monsoon forest, typically contains a range of tree species: only some of which drop some or all of their leaves during the dry season

Examples of tropical seasonal forests

• located in:

  • Madagascar’s lowland forests

  • the Asia-Pacific region

  • North Australia

  • Atlantic forests of Brazil, Central, and Eastern Panama

Climate

• distinct wet (summer) and dry (winter) seasons

• high rainfall (around 1000-2500mm annually)

• temperatures remain warm all year around with little seasonal variation

Ecological impacts/significance

• biodiversity hotspot

  • contains a large variety of different species of plants and animals

  • provides diverse habitats, which supports the needs of the different species

  • seasonal dynamics create unique niches, which promotes adaptation and specialization among species

• climate regulation

  • these forests play a crucial role in regulating the global climate by absorbing and storing large amounts of CO2

  • by storing carbon, these forests help to mitigate climate change and maintain a stable climate

  • they also influence weather pattern, contributing to water cycle

Abiotic factors

• Humidity

• Soil composition

Threats to tropical seasonal forests

• deforestation

  • people tend to clear the land for agriculture, logging and urbanization

• climate change

  • altering rainfall patterns and increasing the frequency and intensity of droughts and floods

• pollution

  • by having an overwhelming majority of water/air pollution, it can strip the forests away from biodiversity, as it may kill species of both plants and animals

Species

• pioneer

  • Trema micrantha (Jamaican nettletree)

  • Croton billbergianus (Billberg Croton)

  • Zanthoxylum ekmanii (prickly-ashes)

• intermediate

  • grasses

  • shrubs

  • small trees

  • lianas

• climax

  • acacia

  • teak

  • mahogany

tundra

• The tundra is a cold, treeless biome found in the Arctic and in high mountains

Examples of tundras

• Arctic tundra

• Antarctic tundra

• Alpine tundra

Climate

• extremely cold with dark winters

• temperatures average around -12℃ ~ -6℃

Ecological impacts/significance

• carbon sequestration

  • tundras act as a large carbon reservoir, trapping large quantities of CO2, making it a vital component of the global carbon cycle

• climate regulation

  • due to its carbon storage capacity, the tundra plays a crucial role in regulating global temperatures

• unique biodiversity

  • despite harsh conditions, the tundra supports specialized plants and animals that are adapted to the cold and short growing seasons

Abiotic factors

• temperature

  • the tundra has cold temperatures, with long winters and short summers

• precipitation

  • the tundra receives less than 25 cm of precipitation annually

• sunlight

• wind

• permafrost

  • a permanently frozen layer of soil that prevents plants from growing deep roots

Threats to the tundra

• climate change

  • rising temperatures are causing permafrost thaw, releasing stored carbon into the atmosphere

• human activities

  • oil and gas extraction, mining and infrastructure development can significantly damage tundra habitats

• invasive species

  • introduced species may disrupt the delicate balance of the tundra ecosystem

Species

• pioneer

  • lichen

  • moss

  • grass

  • sedges

• intermediate

  • dwarf shrubs

  • small trees

  • taller moss

• climax

  • arctic willow

  • lingonberry

  • reindeer moss

deserts

• a desert is a dry, arid region of land that receives little rainfall

• they are the driest biomes on Earth

Examples of deserts

• sahara (Africa)

• atacama (south America)

• Gobi (Asia)

Climate

• extreme aridity

• extreme temperatures

• high evaporation

• day/night temperature fluctuations

Ecological impacts/significance

• carbon sequestration

  • deserts acts as a carbon sink through bacteria in the sand, helping to mitigate climate change

• unique biodiversity

  • deserts support a diverse range of plant and animal life that evolved to survive extreme temperatures and water scarcity

• nutrient cycling

  • desert sands can be a source of essential nutrients for other ecosystems

• landscape shaping

  • desert landscapes can influence weather patterns and water flow in surrounding regions

Abiotic factors

• precipitation

• temperature

• soil

• sand

• sunlight

Threats to the desert

• desertification(human activities)

  • overgrazing, deforestation, and unsustainable irrigation, accelerate the process where fertile land turns into desert

• rising temperatures

  • warmer temperatures can lead to increased evaporation and water scarcity, which is a major challenge for desert ecosystems that are already highly sensitive to water availability

• changing rainfall patterns

  • shifts in rainfall patterns, including increased droughts and intense rainfall events can disrupt the balance of the ecosystem

Species

• pioneer

  • moss

  • lichen

  • grass

  • shrubs

  • acamptopappus shockleyi gray

• intermediate

  • thornscrub

  • shrubs

  • small trees

• climax

  • saguaro cacti

  • ocotillo

3.3

Task

Discuss the case histories of 3 different species: one that has become extinct due to human activity, another that is critically endangered, and a 3rd species whose conservation status has improved by intervention

Extinct

Pinta Island Tortoise (Chelnoidis abiingddonii)

• by mid 20th century, its population had drastically declined

• in 1971, only 1 male tortoise was discovered on Pinta island

• conservation efforts were made to find a mate, but despite attempts to crossbreed him, closely related tortoise species didn’t produce any viable offsprings

• in 2012, the last Pinta Island Tortoise died, marking the extinction of the Pinta Island Tortoise

Ecological role:

• seed dispersal, as it consumed fruits and vegetation

Why did it become extinct?

• habitat loss due to introduction of non-native species (eg goats)

• overexploitation, as a source of fresh meat for sailors and whalers

Critically endangered

California Condor (Gymnogyps californianus)

• it is a large vulture and currently has a highly restricted range in California, Arizona, and Baja

• a current estimation of the population in 2024 is 561

Ecological role:

• scavengers, primary feeding on carrion (dead animals)

Why is it endangered?

• lead poison

  • carcasses often contain lead ammunition fragments left behind by hunters

• low genetic diversity

Improved by intervention

Humphead Wrasse (Cheilinus undulatus)

• found in coral reef ecosystems in the Indo-Pacific region

• Inhabit clear waters near coral reefs

• IUCN first placed it on endangered list in 2004

Ecological role

• regulate population of smaller reef fish and invertebrates as an apex predator

What made them endangered?

• overfishing

  • due to its large size and unique appearance

• habitat degradation

  • coral reef destruction and degradation due to climate change, pollution, and destructive fishing practices

Conservation effort

• implementing fishing regulation

• establish protected areas