Vegetation Exam Review Notes

Ecosystems, Global Biomes, and Prairie Ecosystems

  • Definitions: Understand the following terms:
    • Omnivore: An animal that eats both plants and animals.
    • Detritivore: An organism that feeds on dead organic material (detritus).
    • Autotrophic: An organism capable of synthesizing its own food from inorganic substances, using light or chemical energy.
    • Abiotic: Non-living chemical and physical parts of the environment that affect living organisms and the functioning of ecosystems.
    • Producers: Autotrophic organisms that produce their own food (e.g., plants).
    • Herbivores: Organisms that eat plants.
    • Consumers: Organisms that eat other organisms.
    • Detritus Feeders: Organisms that consume detritus.
    • Mutualism: A symbiotic relationship where both organisms benefit.
    • Population: A group of individuals of the same species living in the same area.
    • Food Web: A network of interconnected food chains.
    • Ecotone: A transition area between two different ecosystems.
    • Ecosystems: A community of living organisms interacting with each other and their physical environment.
  • Predator-Prey Relationships: The ecological interaction where one organism (predator) kills and eats another organism (prey).
  • Examples of Detritus: Dead leaves, animal waste, and other organic matter.
  • Trophic Levels:
    • Producers (autotrophs) form the base.
    • Herbivores (primary consumers) eat producers.
    • Carnivores (secondary and tertiary consumers) eat other animals.
  • Energy Movement in Food Chains: Energy flows from one trophic level to the next; a significant amount of energy is lost as heat at each transfer (typically around 90% loss, so only 10% is transferred).
  • Resource Partitioning: The process where species minimize competition by using resources in different ways, at different times, or in different places.
  • Climate and Biomes:
    • Desert: Low precipitation, high temperatures.
    • Temperate Deciduous Forest: Moderate precipitation, distinct seasons, moderate temperatures.
    • Grasslands: Moderate precipitation, distinct seasons, moderate temperature ranges.
    • Tropical Rainforest: High precipitation, high temperatures year-round.
    • Tundra: Low precipitation, very cold temperatures, short growing season.
  • Landscape/Biome: A large naturally occurring community of flora and fauna occupying a major habitat, e.g., forest or tundra.
  • Habitat vs. Niche:
    • Habitat: The environment where an organism lives.
    • Niche: The role and position a species has in its environment; how it meets its needs for food and shelter, how it survives, and how it reproduces.
  • Types of Prairies:
    • Short Grass Prairie: Found in drier western areas, lower rainfall.
    • Mixed Grass Prairie: Transition zone with moderate rainfall.
    • Tall Grass Prairie: Found in wetter eastern areas, higher rainfall.
  • Climax Community of Illinois Pre-Settlement: Dominated by tallgrass prairie ecosystems.
  • Fire and Prairie Ecosystems: Fire is a natural and essential component; it prevents the encroachment of trees and promotes the growth of prairie grasses and forbs.

Forest Biomes and Public and Private Lands

  • Reasons for Deforestation in Developing Countries: Agriculture, logging, and economic development.
  • Methods of Tree Harvesting:
    • Clear Cutting: Removing all trees from an area; leads to significant habitat loss and erosion.
    • Selective Cutting: Removing only mature trees; less disruptive but can still impact forest structure.
    • Shelter-wood Cutting: Removing mature trees in stages; provides some protection for regenerating trees.
  • Goal of Sustainable Forestry: To manage forests to meet the needs of the present without compromising the ability of future generations to meet their own needs.
  • Economic Values of Forest Products: Timber, fuelwood, and non-timber forest products.
  • Sustainable vs. Unsustainable Use of Forests: Balancing economic gain with environmental protection vs. exploiting forests without regard to long-term consequences.
  • Location of Publicly Owned Land in US: Predominantly in the western states.
  • Goal of US Forest Service’s Multiple Use Policy: To manage national forests for a variety of purposes, including timber harvesting, recreation, and wildlife habitat.
  • Goals of “New Forestry”: Focuses on maintaining ecological integrity and biodiversity, rather than solely timber production.
  • Old Growth Forest Preservation: Protecting forests that have never been logged and have high biodiversity.
  • Private Land Trust: Nonprofit organizations that protect land for conservation purposes; examples include The Nature Conservancy.
  • Indirect Use of Values of Forests: Ecosystem services such as carbon sequestration, water purification, and erosion control.
  • Wilderness Areas: Areas with the highest level of protection from development.
  • Functions of National Wildlife Refuges: To provide habitat for wildlife and manage for their conservation.
  • National Park Systems Goals: To preserve natural and historical resources and provide for public enjoyment.

Ecological Succession, Ecosystem Stability, and Value

  • Primary Succession Example: Moss growth on bare rock, which breaks down the rock and eventually creates soil.
  • Ecological Succession in a Temperate Deciduous Forest:
    • Bare soil invaded by grasses.
    • Shrubs begin to grow.
    • Conifers establish themselves.
    • Deciduous trees eventually dominate.
  • Fire and Succession in Yellowstone N.P. (1988): Fire resistant species, like lodgepole pine, thrive after fires, and the fire promotes biodiversity by creating a mosaic of habitats.
  • Monocultures: Decrease biodiversity and decrease ecosystem stability; they are more susceptible to pests and diseases.
  • Ecosystem Services and Functions: Review table in textbook chapter 5.5.
  • Energy Flow Through an Ecosystem: Directed by the sun; energy flows from producers to consumers.
  • Human Appropriation of Primary Production: Humans have appropriated a significant percentage of land primary production to support their needs, reducing available resources for other species.

Laboratory Component

  • Light Intensity Between Grassland and Shrub Seral Stages: Light intensity is typically higher in grassland seral stages compared to shrub seral stages due to less canopy cover.
  • Examples of Nature Study Area Prairie Plants:
    • Blazing star
    • Goldenrod
    • Indian grass (Gold stem)
    • Big blue stem
    • Cord grass
    • Rattlesnake Master
    • Prairie dock
    • Compass plants