Ecology Chapter on Niche and Competition

Niche

• Fundamental Niche: The ideal conditions a species needs to survive. This includes factors such as food, temperature, and habitat.
• Realized Niche: The actual conditions a species exists under, influenced by interactions with other species, like competition.

Competition

• Competitive Exclusion Principle: Two species cannot occupy the same niche indefinitely. One species will either leave or die out.

Specialists vs. Generalists

• Generalists: Have a wide fundamental niche, able to survive in various habitats and consume diverse food sources. (e.g., raccoons).
• Specialists: Have a narrow fundamental niche due to specific needs, making them more susceptible to environmental change. (e.g., pandas, reliant on bamboo)

Evolution

• Co-evolution: Species evolve adaptations in response to each other, driven by natural selection.

Diversity of Life History Traits

• Life History: The set of traits related to an organism's development, growth, reproduction, and lifespan.
• Interspecific Interactions: Interactions between different species create selection pressures that drive adaptations in life history.
• r vs. K Strategists:
  • r-strategists: Focus on high growth rates (r). They reproduce quickly, have many offspring, and often have short lifespans. They thrive in unstable environments and are often generalists.
  • K-strategists: Focus on reaching carrying capacity (K), the maximum stable number of individuals an environment can support. They reproduce slowly, have fewer offspring, and tend to have longer lifespans. They require stable environments.

Patterns in Ecology

• Biogeography: The study of the geographical distribution of organisms and the factors that influence their location.
• Geographic Range Limits: Are shifting due to climate change, impacting species distribution.
• Ecological Succession: The gradual change in an ecological community over time.
  • Pioneer Species: (r-strategists) First to colonize a new or disturbed area.
  • Climax Community: (K-strategists) The stable community that eventually develops in a particular environment.
  • Primary Succession: Occurs on land not previously occupied by a community, such as bare rock or volcanic ash.
  • Secondary Succession: Occurs after a disturbance to an existing community, such as fire, flooding, or human disturbance.

Invasive Species

• Exotic species introduced to an area outside their native range can disrupt the ecological balance.

Ecological Impact Assessment (EIA)

• Any new type of infrastructure is considered development.
• An EIA is a formalized process assessing the impact of a proposed development.
• An EIA must assess current conditions, likely impacts, and propose mitigation strategies for negative effects.

EIA Goals

• Ensures proposed projects meet legislative requirements.
• Determine environmental acceptability.
• Minimize environmental impacts.

History

• EIAs are conducted in over 140 countries.
• The first EIA was created in the US.
• The US National Environmental Policy Act (NEPA) was inspired by Rachel Carson's "Silent Spring" (1962).
• The Council on Environmental Quality (CEQ) was established by NEPA.
• CEQ coordinates federal environmental efforts, oversees EIA implementations, and acts as a referee between agencies.

EIA Screening

• Large environmental impact projects (mining, large developments) always require an EIA.
• Projects with no potential for significant environmental impact are excluded.
• Projects in the "gray area" are screened for potential risks to determine if an EIA is necessary.
• Screening factors include:
  • Project size.
  • Resource use.
  • Amount and type of waste produced.
  • Land use: Existing site conditions, environmental sensitivity and surrounding land use.
  • Potential impact: Severity, probability, and geographical extent.

EIA Receptors

• EIA receptors are determined through surveys.
• Receptor examples include:
  • Abiotic parameters: Soil, air, water.
  • Landscape/ecology: Visual intrusion and ecology.
  • Emissions: Waste, pollution, greenhouse gasses.
  • Material assets: Heritage and archeology.
  • Population: Economy, infrastructure, employment, and noise pollution.
  • The focus is on the ecology receptor.

Ecological Risk Assessment (EcIA)

• EcIA evaluates the likelihood of adverse ecological effects caused by chemical, physical, or biological stressors.
• EcIA is considered for almost every EIA.

Stages of EcIA

• Baseline stage: Uses secondary data like NEPAssist.
• Primary data collection: Uses field studies like bird point counts and semi-quantitative vegetation surveys.
• Detailed follow-up studies are conducted for specific receptors such as:
  • Habitat receptors: Condition, type, fragmentation, corridors, and connectivity.
  • Flora-based receptors: Presence of plants.
  • Fauna-based receptors: Presence of animals.
  • Process-based receptors: Pollination, seed dispersal, and symbiotic relationships.

Ecological Value Definitions

• Site value:
  • Statutory designation: State/national park or wildlife refuge.
  • Habitat heterogeneity: More diverse habitats = higher value.
  • High species richness: Higher biodiversity = higher value.
  • High population percentage: A location with over 1% of a species' population is valuable.
  • Social value: Public connection to a site often correlates with high biodiversity and habitat heterogeneity.
• Habitat value:
  • Rarity: National or international rarity.
  • Decline: Declining or vulnerable habitat.
  • Specialty: Highly specialized habitat or restricted location.
  • Difficulty of recreation: Ancient forests are hard to recreate.
  • Human Usefulness: Wetlands for flood control.
• Species value:
  • Legal protection: International, federal, or state protection.
  • Rarity: IUCN (International Union for Conservation of Nature) conservation status.
  • Ecosystem engineers: Important species like beavers, even if not rare.
  • Economic importance: Value to human livelihoods.
  • Non-native species: How to manage non-native species during development.
• Ecosystem service value:
  • Combination of site, habitat, and species values that benefit humans.
  • Processes/services: Pollination, water filtration, carbon sequestration.

Assessing Project Impacts

• Prediction and uncertainty: Assessing impacts involves considerable prediction and uncertainty.
• Impacts are assessed for the project's full life cycle:
  • Construction.
  • Operation.
  • Decommissioning.
  • Regeneration: Returning the site to a natural state after decommissioning.

Types of Impact

• Direct: Direct impact from development, such as pumping waste from a power plant.
• Indirect: Indirect impacts from development, such as waste water polluting a river and causing harmful algal blooms (HABs).
• Cumulative effect: Exceeding a threshold, like thermal pollution in a large body of water.
• Ecological benefits: Potential positive impacts from development activities that can benefit the environment.
  • Remediation of brownfields or superfund sites can be considered an ecological benefit.
• Magnitude: The spatial scale of the impact: The area being impacted.
• Importance: The severity of the impact and the ecological importance of the area.

Impact Prediction Methods

• Expert opinion: Using existing ecological knowledge.
• Peer-reviewed literature: Consulting published ecological research.
• Previous projects and monitoring: Using data from previous projects and post-construction surveys.
• Modeling approaches: Using predictive models, which can be inaccurate.
• Leopold matrix: A tool used to assess impacts based on magnitude and importance.

Impact Mitigation

• Mitigation measures: Reducing negative impacts before they happen.
  • Avoidance: Preventing the development or reducing its scale to minimize impacts.
  • Reduction: Implementing measures to lessen the severity of impacts.
  • Containment: Keeping impacts localized.
  • Rescue: Relocating threatened species or habitats.
  • Remediation: Removing and recovering from environmental issues.
  • Spatial approach: Altering site location or movement patterns.
  • Temporal approach: Altering timing to avoid sensitive periods (spawning season).
  • Development alterations: Design and construction changes.
  • Translocations: Moving species or habitats off-site (controversial).
• Compensation: Compensating for losses by creating replacement habitats or providing financial incentives.

Outcomes of EcIA

• Granted: With mitigation conditions and post-development monitoring.
• Withheld: Pending implementation of mitigation measures or alternative sites.
• Denied: Impact too high or insufficient mitigation.

This quiz explores the concepts of fundamental and realized niches, competition among species, and the distinctions between generalists and specialists. Additionally, it covers co-evolution and life history traits, providing a comprehensive understanding of ecological interactions.