Biomes
What are the characteristics of the tundra biome?
-Cold, frozen climate, small vegetation in patches close to the ground
-Considered dry desserts, get less than 25cm of precipitation per year
-Long, cold winters
-Largely permafrost all year
Arctic tundra: above the arctic circle or in southern Antarctica
Alpine tundra: very high elevation on mountains
What are the characteristics of the grassland biome?
-Largest land biome
-Coniferous trees
-Freezing temperatures for 6-8 months
What is the first level of the food pyramid?
Primary producers + first tropic level
Dominant species
Abundant and have a lot of influence over an ecosystem, may result in a loss of biodiversity if removed
Ex. trees, kelp, caribou, kangaroo
What are the spheres?
Lithosphere (land), hydrosphere (water), atmosphere (air), biosphere (living things)
The biosphere is the only biotic sphere, while the others are abiotic
They interact to cause Earth’s systems and processes
What are the characteristics of the tropical rainforest biome?
-Tall trees
-High amounts of rainfall
-Very diverse and complex
-Between 18-30 degrees, high humidity
-2-6% of the Earth‘s surface
-Largest rainforests are in the Congo River in Africa and Amazon River in South America
-Help regulate climate with trees and soil
-Health damaged by human activites
What are the characteristics of the coral reef biome?
-Very diverse
-Warm, tropical waters
-25% of ocean species rely on this biome
-Severely threatened
What is the second level of the food pyramid?
Primary consumers + second tropic level
Keynote species
Can greatly affect population numbers and the health of an ecosystem, generally not abundant but equally as important as dominant species
Ex. sea otters in BC kelp forests
What is the 10% rule?
Only 10% of biomass from each level of the food pyramid moves on to the next higher level of the pyramid
This is because not all parts of energy are consumed or digested, causing apex predators to be less populated than primary consumers
What are the characteristics of the dessert biome?
-Extremely dry
-Cover 1/5 of land
-Less than 25cm rainfall per year
-Plants and animals adapt to conserve water
-Well-known desserts are the Sahara Dessert in Africa and Mojave Dessert in south USA
What is photosynthesis and the formula for it?
CO2 + water = oxygen + sugar
Chlorophyll (causes green pigment) in plants uses solar energy to convert sugar and water into sugar and oxygen
It is vital to the biosphere, generating oxygen. Not all parts of the biosphere produce oxygen at the same rate.
What is the third level of the food pyramid?
Secondary consumers + third trophic level
Ecosystem engineers
Species that cause such dramatic changes to a landscape it creates a new ecosystem
Ex. Beavers
What are the four main limiting factors and how do they affect carrying capacity?
The amount of space, food, water, and shelter
These affect the number of resources available to species, and the carrying capacity is the amount of a species that can be supported by the resources available
What are the characteristics of the grassland biome?
-Large, open areas and grass
-Grazing animals, low amounts of rainfall, and wildfires maintain grasslands
-Climate is only ideal for grass, not trees
Savannas: warm climate, short rainy season, long dry season, abundant wildlife, mostly in Africa but also in South America and Asia
Temperate: richer soils, in North America
Extinction occurs when the death rate is higher than the birth rate
Background extinction is more gradual
Mass extinction occurs quickly from a sudden change
What is the fourth level of the food pyramid?
Tertiary consumers + fourth tropic level
Producers and consumers
Producers: Called autotrophs. Get nutrients from the sun, water and CO2 Usually use photosynthesis, and are the foundation of every ecosystem
Ex. trees and algae
Consumers: Called heterotrophs. Get nutrients by eating other living things (producers or other consumers)
Ex. wolf, rabbit
What are alien and invasive species?
Alien species: species that arrive to a new location, and can be harmless or beneficial to their new environment. Can also be called non-native or exotic species
Invasive species: a kind of alien species that upsets the equilibrium of an environment and harm native species. An example is the Zebra Mussel native to Asia that came to the Great Lakes in the 1980s under ships. They out-competed other organisms in the habitat
What are the characteristics of the deciduous forest biome?
-Trees that lose years yearly based on the seasons
-Regions with seasonal weather
-Diverse plants
-Variety of wildlife
What is exponential growth?
Unlimited growth that produces a curve when graphed, usually only occurs under certain conditions and short periods of time
What is the fifth level of the food pyramid?
Apex consumers + fifth trophic level
Decomposers
Break apart dead organisms into simpler inorganic materials, making nutrients for producers
All parts of the food chain can go back to decomposers
Ex. worms, bacteria
Definition of equilibrium
The balance between opposing forces