Ecology Pt. 3
A _________ community is a stable community that results from ecological succession
climax
Define ecological succession.
The gradual change or replacement of species in a community over time.
__________ is a biome with a coastal "Mediterranean" climate.
Chaparral
The _________ is permanently frozen soil found in the tundra.
permafrost
____________ is the lowering of the pH of the ocean.
Name two ways that nitrogen is fixed (meaning that it is made into a form that living things can use).
Nitrogen fixing bacteria
Lightning
What is primary succession? Name an example.
Primary succession is ecological succession that occurs in previous uninhabited areas.
Examples:
Land that is uncovered when a glacier retreats
New islands exposed after volcanic eruptions
The two factors most important in determining a biome's climate are:
temperature and precipitation
Name two characteristics of temperate grasslands.
Around 30 degrees north or south of the equator
Covers large areas of the interior of continents
Moderate rainfall
Often caused by rain shadows
Periodic fires
Four seasons with temperature variation throughout the year
How do you determine if a community is more even than another community?
If its relative abundances are generally similar.
Ex. If each species in a community has a relative abundance of about 30%, it is more even than a community that has one species that is about 70% and several other species with much lower relative abundances.
Name three pioneer species.
lichens
bacteria
moss
weeds
Name three benefits of fire to ecosystems.
Removes excess brush and deadwood
Helps return nutrients to the soil
Allows new trees to flourish
Name three threats to tropical rainforests.
Climate change
Habitat loss
Illegal poaching
Forests in cold climates typically have higher amounts of nutrients in their soil than those in warm climates because:
Their cold seasons, when there isn't much growth, allow nutrients to build up in the soil.
Name three characteristics of plants. What is their main role in ecosystems?
Multicellular
Autotrophs
cell walls
etc.
Plants are producers that form the basis of land ecosystems
Name the steps of the short-term carbon cycle.
Photosynthesis: plants take in CO2 in order to make carbohydrates
Consumption: Living things eat plants, transferring carbon from one organism to another
Cellular respiration: Living things produce CO2 and release into the atmosphere when they use carbohydrates for energy.
Which community is likely a climax community and which is like a pioneer community? How did you know?
Community 1 # Relative abundance
Reindeer Lichen 715 71.5%
Fireweed 93 9.3%
Hypnum Moss 185 18.5%
Willow Trees 7 0.7%
Community 2
Sugar Maple 300 30%
White Spruce 100 10%
Eastern Hemlock 275 27.5%
Blue Grama 325 32.5%
Community 1 is the pioneer community (early in ecological succession) as it includes many pioneer species like lichens, moss, and weeds.
Community 2 is likely a climax community because it is mostly made up slow-growing trees and is relatively even (similar relative abundances)
Plants and animals in the savanna are adapted to survive its ___________. Name three adaptations of plants and/or animals to survive in the savanna
Wet and dry seasons
Plant adaptations:
Losing leaves during the dry season
Large, horizontal root systems
Vertical leaves to reduce sun exposure
Thorns to protect against herbivores
Animal adaptations:
Migration to find water
Giving birth during the wet season
Ecological niche differentiation (niche partitioning)
What is the taiga? What are plants and animals in the taiga adapted to survive? Name two adaptations of animals to survive in the taiga.
northern forests with coniferous (evergreen) trees
Plants and animals in the taiga are adapted to survive cold temperatures.
Animal adaptations:
Migrate south
Hibernate
Change coat colors
I am measuring basketball bounce heights based on different air pressures. In this experiment, the different air pressures are the ______ and they would be found on the _-axis on a graph
independent variable
x-axis
Describe the steps in the process of old-field succession, including the plants that occur at each step. Is old-field succession primary or secondary succession?
Secondary succession that occurs when farmland is abandoned
1. Pioneer species, like weeds and grasses, come in
2. Over time, intermediate species like taller plants move in
3. Small trees move in, taking over the community
4. Slow-growing trees then start to take over
What is the phosphorus cycle? Name two ways that phosphorus naturally enters ecosystems. How do humans contribute to the phosphorus cycle?
Phosphorus enters ecosystems through the weathering of rocks and through decomposition and animal waste
Humans contribute to the phosphorus cycle when they apply agricultural fertilizers with phosphorus nutrients to plants
Provide two characteristics of desert biomes. What are three adaptations of plants to survive in the desert? ________ is the process by which animals become dormant to survive extremely dry conditions.
Desert characteristics:
Widely scattered vegetation
Very low precipitation
Wide temperature changes between day and night
located near mountains
Plant adaptations:
Thick, fleshy stems
Spiny leaves
Waxy layer on leaves to prevent water loss
Shallow roots systems
Dropping leaves during dry periods
Estivation = dormancy during dry periods
On the board, draw a climate graph that shows the climate conditions in the tropical rainforest.
Climate graph shows high precipitation that decreases during the summer months. Temperatures stay consistently high throughout the year.
On the board, draw a climate graph that shows the climate conditions in temperature grasslands.
The graph should show increases in temperatures and precipitation during the spring and summer months. Changes follow patterns you would expect based on four seasons.