ECO4 Flashcards
(18 cards)
What is Ecological Balance?
A state of dynamic equilibrium where biodiversity remains relatively stable despite gradual changes.
What is Dynamic Equilibrium?
Ecosystems are generally stable over time but can be disrupted by species introductions, extinctions, or natural/human-caused events.
What are Limiting Factors?
Environmental factors that prevent a population from reaching its biotic potential.
What are Density-Independent Factors?
Affect population size regardless of density (e.g., floods, fires, temperature extremes).
What are Density-Dependent Factors?
Effects depend on population density (e.g., food supply, disease, competition).
What is Carrying Capacity?
The maximum population size that an ecosystem can support sustainably.
What is Bottom-Up Regulation?
Ecosystem structure controlled by producers and abiotic factors (e.g., sunlight, water, soil nutrients).
What is Top-Down Regulation?
Ecosystem structure controlled by top predators (e.g., wolves controlling deer populations).
What is a Keystone Species?
A species that has a disproportionately large impact on its ecosystem. Removal causes drastic changes.
What is a Trophic Cascade?
An ecological phenomenon triggered by the addition/removal of top predators, resulting in ripple effects through lower trophic levels.
What is Ecosystem Productivity?
The rate at which producers capture and store energy (influenced by sunlight, moisture, nutrients).
What is the Gaia Hypothesis?
The idea that Earth functions like a single living organism, requiring energy input and nutrient cycling to maintain balance.
What is Biological Magnification?
The process by which toxic substances (like DDT or mercury) increase in concentration at higher trophic levels.
What is the DDT Example?
A pesticide that caused eggshell thinning in birds, leading to population declines; linked to health issues in humans. Now banned in many countries.
What are Invasive Species?
Non-native species that spread rapidly, often due to a lack of predators. Can disrupt ecosystems and cause harm to economy, health, and native species.
What are Human Impacts on Ecosystems?
Include habitat destruction, pollution, climate change, overfishing, urbanization, and introduction of GMOs.
What is Wetlands Importance?
Wetlands filter pollutants and support biodiversity, but are often drained for development.
What are Dead Zones?
Areas in aquatic ecosystems with low oxygen due to excess nutrients and algal blooms, often caused by fertilizer runoff.
