Studied by 13 people
What are biomes?
a form of ecosystems that are smaller than the biosphere
What are the 2 major abiotic factors of a biome?
temperature & precipitation
Describe the climate of hot deserts:
High daytime & low nighttime temperature; generally light winds
>250mm of rainfall annually; high evaporation rates
Describe the soil of hot deserts:
Light colored soil that’s dry & sandy; top layer may be absent/very thin due to lack of vegetation
What’s an example of a plant’s adaptation to the hot desert?
Cacti have drought tolerant seeds with waxy cuticles to prevent water from escaping
Examples of human impact in hot deserts:
mining
removal of rare species
use of groundwater + drying out surface water
Describe the climate of tropical rainforests:
Temperatures range from 22-31°C; low diurnal temperature (difference b/t high and low temperature in the same day)
2000mm of rainfall per year w/ high humidity levels; daily convectional rainfall
Describe the soil of tropical rainforests:
Red/yellow soil
high rainfall = nutrients + clays being leached out & replaced with aluminium oxide (high rate of decomposition)
Example of a plant’s adaptation to the tropical rainforest?
Tall + thin trees allow for light
thin bark eliminates the need to conserve water
leaves have a waxy surface with drip tips to allow excess water to runoff + prevent algae
Supports high biodiversity
Examples of human impacts in the tropical rainforest:
Deforestation: causes fragmentation + lost of tropical forests
Plants + animals in the fragmentation ecosystem remain vulnerable (those that do survive cause a rapid decline in biodiversity)
Loss of genetic material + biodiversity
Soils are thin + lack nutrients → due to leaching & heavy rainfall
Nutrients = stored in biomass
Completely deforested areas → soils collapse + high soil erosion
Contributes to climate change → forests store a lot of carbon (e.g. in photosynthesis)
Mining
Farming
Describe the climate of grasslands
Temperatures range from 20-35°C
Up to 750mm of rainfall annually w/ wet summer; unpredictable rainfall
Distinct dry & wet seasons
Describe the soil of grasslands:
Red soil (high iron), highly weathered + porous allows for rapid drainage & thin layer on surface decays rapidly due to high temperatures
Soils aren’t very fertile; limited vegetation
Describe the vegetation in grasslands:
grasses & umbrella shaped trees
Trees are spread apart & root systems are either widespread (to absorb water) or deep (reach groundwater during dry season)
Human impact examples in grasslands:
grazing
urbanization
less biodiversity due to loss of habitat + hunting
Describe the climate of tundras:
Temperatures range from -34-12°C; strong polar winds
Less than 250mm of rain annually & short summers
Describe the soil of tundras:
Dark brown soil, permafrost (permanently frozen) sub layer, organic material at surface
Describe the vegetation in tundras:
small plants that grow close together & are low to the ground
Waxy hair to coat them from cold & wind, shallow root systems due to permafrost
Human impact examples in tundras:
melting of permafrost (methane)
drilling for resources
What is ecological succession?
process of an ecosystem changing & developing
Describe primary succession:
no soil present / uncolonized areas
longer time to reach climax community than secondary succession
examples: new lava flow & newly formed sand dunes
Examples of pioneer species + their impact in primary succession:
Pioneer species (lichens & mosses) will establish themselves on bare rock
Start formation of soils by breaking down the rock → grasses + shrubs can grow
Describe secondary succession:
colonized area that was disturbed or damaged (hasn’t eliminated all life/removed all nutrients)
Pioneer species = small plants
example: where a mudslide occurred
What’s an intermediate community?
a change from the initial community, but the final stage hasn’t been reached
What’s a climax community?
final stage of succession; depends on climate
can take a few days to hundreds of years
Species involved in succession are controlled by abiotic factors like:
geology & climate
What is primary productivity?
the rate in which energy is converted into organic material by autotrophs
What is gross primary productivity?
total amount of biological productivity within ecosystem/biome - all production by producers
Energy production per unit area / units of time
What is net primary productivity?
amount of energy captured minus energy used for respiration
GPP - R
What are abiotic factors that affect productivity?
CO2, water, sunlight
What do ecological/trophic pyramids represent?
Compare communities within/between ecosystems by analyzing their trophic levels
Represents energy, number of individuals/biomass in each trophic level
A pyramid of energy shows:
feeding relationships of an ecosystem
Greatest amount of energy at the bottom → ~10% transfer of energy b/t levels
Energy loss as heat due to respiration & excretion
What is a pyramid of numbers?
# of individual organisms in an ecosystem
Normal pyramid of numbers: largest # of organism at the bottom
Producers at bottom & tertiary consumers at the top
Along with a pyramid of biomass can have an unusual/inverted shape
Number below can support upper trophic levels
What is a native species?
originated & developed in a specific region/ecosystem and adapted to living there
Indigenous: occurring naturally in a specific area; native to an ecosystem
What is an invasive species?
outcompete other species in the area it has invaded → changes balance in the ecosystem it invades
Can be native (outcompete other organisms in the ecosystem) or non-native
Primarily spread through human activity & often spread rapidly
Degrade native ecosystems → harmful to human health + local economies
Potential impact of invasive species include:
grazing
competition
predation
disease transmission
How is food security a benefit of conserving biodiversity?
protects plants, animals, & genetic resources that support soil fertility, disease regulation, & pollination of crops
How is economic growth/poverty reduction a benefit of conserving biodiversity?
many poor populations depend on natural areas for their livelihoods; forests provide timber, food, & water
How is combating climate change a benefit of conserving biodiversity?
forested areas can reduce CO2 levels & coastal ecosystems can lessen the impact of storm surges
How are medical resources a benefit of conserving biodiversity?
medicinal qualities in plants to treat illness
How is high genetic diversity a benefit of conserving biodiversity?
greater stability → species are able to adapt to various conditions (e.g. disease & climate change)
How is cultural + recreational value a benefit of conserving biodiversity?
biodiversity reflects social values + local beliefs
e.g) a culture may use rivers for baptism
How can sustainable harvest conserve biodiversity?
use of a resource that ensures its constant supply without harming future yields/causing irreversible damage to an ecosystem
Optimal harvest (set % of resource is harvested) & systematic random sampling (set % of material harvested from a defined part of an ecosystem) are sustainable
What is CITES?
aims to ensure sustainable trade & protect endangered animals + species
Limitation: hasn’t stopped illegal trade of protected species & voluntary participation
What’s the IUCN Red List?
scientific info + tools to guide int’l actions in conservation
What is EDGE?
aims to protect species on the verge of extinction & have unique evolutionary history
EDGE Score: combined endangered conservation status + distinctiveness of species
What is captive breeding?
breeding endangered species in captivity with the goal of releasing them back into protected wild areas in the future
Aims to develop a self-sustaining population of a species
Can lead to inbreeding w/ weak genetic traits → lower survival rates
How can rewilding contribute to habitat conservation/creation?
restoring an area of land to its natural uncultivated state
Reintroduced species + communities can thrive → biodiversity increases & ecosystem health improves
How can protection of habitats contribute to habitat conservation/creation?
protects the whole habitat + each species benefits
Encourages species protection & biodiversity conservation
How can nature reserves contribute to habitat conservation/creation?
legally protected area that is of importance for organisms or geology
Conservation, protecting natural resources, & scientific research
How can national parks contribute to habitat conservation/creation?
protects landscapes, wildlife, & natural features of large areas that are of conservational, education, or scientific interest
Protected by national laws
How can marine conservation zones contribute to habitat conservation/creation?
nat’l/int’l importance with rare or threatened species + habitats that require protection
Typically don’t have a fishing ban, but have “no-take” zones (prohibits destroy natural resources)
MCZs form a greater network of protected zones
How can deforestation impact a tropical rainforest?
causes fragmentation + lost of tropical forests
Plants + animals in the fragmentation ecosystem remain vulnerable (those that do survive cause a rapid decline in biodiversity)
Loss of genetic material + biodiversity
How can mining impact tropical rainforests?
forests being made into roads + infrastructure
Mining can lead to water, air, soil, noise, & light pollution
How can agriculture impact a tropical rainforest?
depletes the soil of nutrients due to soil erosion
Soils are thin + lack nutrients → due to leaching & heavy rainfall
Nutrients = stored in biomass
Completely deforested areas → soils collapse + high soil erosion
How can climate change impact a tropical rainforest?
forests store a lot of carbon (e.g. in photosynthesis)
How can int’l agreements manage human activity in tropical rainforests?
manage species + forested areas through sustainable harvesting(e.g. CITES)
Need to include: educating those exploiting resources & providing consequences to negative action(s)
How can legislation + protected areas manage human activity in tropical rainforests?
establishment of anti-deforestation public policies + private measures can significantly protect forested areas, biodiversity, + forest’s ability to absorb CO2
Needs to be rolled out across countries w/ large areas of tropical rainforests
How can debt reduction manage human activity in tropical rainforests?
many tropical rainforests are found in LICs that have high levels of debt
Instead of remove rainforests to generate income → some HICs agreed to write off debt
In return, HIC asks for the protection of an area of the rainforest
Why should we preserve tropical rainforests?
maintain biodiversity
protect the production of resources
manage climate change
manage local water quality
Examples of human impact in Antarctica:
Climate change: warming oceans → loss of ice
Ocean acidification (from excess CO2) has caused a loss of biodiversity
Fishing: overfishing leads to the loss of krill, which can lead to the collapse of food chains
Tourism: increases potential of oil + sewage spillage (pollution)
Can disturb colonies of Antarctic animals
No individual gov’t has the power to set regulations
Ozone depletion: CFCs → hole in the ozone layer in the stratosphere above Antarctica
Strong and frequent winds + storms
What are some strategies for managing the impacts of humans of Antarctica?
Legislation & int’l agreement (e.g. The Antarctic Treaty):
Features like: banning the mining of minerals & no nuclear testing/disposal of nuclear waste
Tourism control through agreements like the IAATO
Stricter agreements are being put into place
Educate tourists, reduce noise & light pollution, waste management policies
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