Plants and the Ecosystem Flashcards
What is the role of plants in the carbon cycle?
Plants turn carbon dioxide into oxygen through photosynthesis, (animals do the opposite in cellular respiration)
This helps maintain balance in the CO2 and O2 levels
What is the role of plants in the nitrogen cycle?
Bacteria in soil convert decaying matter to ammonium
Other bacteria convert ammonium into nitrites and nitrates
Plants can use nitrates to produce molecules needed for plant growth
Dead plants get turned into ammonium
What is the role of plants in the Phosphorus cycle?
Phosphate is absorbed by plants and used to synthesize organic compounds
Plants get eaten by animals who use Phosphorus to make DNA, ATP and bones
When plants and animals die, decomposers return some of the phosphorus to the soil
Role of plants in erosion control
Roots create a carpet-like barrier which slows the carrying away of sediment
Role of plants in cleaning contaminated soils
Some plants, called hyperaccumulators, can extract toxic metals from the soil and concentrate them in their roots
Have been used to clean abandoned mines of toxic substances
Role of Wetlands in sustaining the ecosystem
Wetlands can extract carbon, phosphorus and nitrogen that is buried deep in the ground and plants clean the water by absorbing the elements
Often located near rivers or streams and help keep water clean preventing algal blooms
Slow water as it exits rivers and streams preventing erosion
Explain how Cacti survive extreme conditions
Stems are made of thick hard cell walls allowing for water storage
Can have spongy or hollow interiors
Have ribs which allow for expansion or contraction when cactus is full or empty
Don’t have leaves and don’t undergo transpiration
Explain how coniferous trees survive winter
Needles perform photosynthesis year round and allow for minimal transpiration
Roots are shallow and cover long distances allowing for nutrient consumption in topsoil and better anchorage
Bark is thick allowing for protection from cold and forest fires
Seeds are kept in cones that close in the cold and open in the warmth
Explain the dormancy of deciduous trees in winter
Chlorophyll is broken down in the fall
Leaves fall off and scar forms to maintain water and prevent infection
Acclimation occurs allowing the tee to withstand colder temperatures
The roots and inner bark store sugars for use in winter
Explain how arctic plants survive winter
Contain substances similar to antifreeze allowing them to grow in cold temperatures
Grow close to the ground to hide from wind
Shallow roots, topsoil is the only thing that thaws
Small leaves, less water loss through transpiration
Cone shaped flowers direct heat to middle of flower
Most are perennials
What is the role of natural shoreline vegetation
Provides food and shelter
Provides a spawning bed for fish
Enhances water quality (can filter harmful substances)
Traps runoff and excess nutrients
Shades and cools water
Discourages growth of algae and aquatic plants
List the issues with disrupting a shoreline
Removal of plants speeds up erosion and lowers water quality
Replacing native plants with non-native plants can disrupt the ecosystem
Building lawns and golf courses disrupts the riparian zone
How can you help a shoreline
Plant native species
Try not to disrupt any of the zones
List the disadvantages to fertilizer use
Nutrients can affect soil quality and can dissolve in water being carried to lakes, rivers and streams causing algal blooms
Can harm roots of plants due to concentration of nutrients being too high
Can affect long term soil composition
Can dwindle fossil fuel supply (many fertilizers use fossil fuels in their production
What is a Riparian buffer zone?
Zone between a manicured lawn and the shoreline where native species are allowed to grow ADV - prevention of soil erosion - absorption of harmful chemicals - protection for native wildlife - shade along waterfront - ease of maintenance protection from wind
