Analyze Ecosystem Change and Recovery - Biology

Number of different species present in a defined area. Higher richness generally indicates healthier, more stable ecosystems.

Increasing native species richness and stable nutrient cycling. Indicates restoration of ecological structure and function.

High nitrate/phosphate with low dissolved oxygen and algal blooms. Nutrients fuel algae; decomposition depletes oxygen levels.

Ability to remain relatively unchanged when disturbed. Stable systems show high resistance to environmental changes.

$800$. Add respiration to net primary productivity: $500 + 300$.

Indirect effects across trophic levels triggered by predator changes. Classic example: wolves controlling deer populations affects vegetation.

$400$. Subtract respiration from gross primary productivity: $1200 - 800$.

$NPP = GPP - R$. NPP is energy remaining after plants use some for respiration.

How evenly individuals are distributed among species. High evenness means no single species dominates the community.

Species whose presence or absence reflects specific environmental conditions. Used for monitoring ecosystem health and environmental quality.

Net primary productivity (NPP) rate. Measures energy available to support higher trophic levels.

Correlation shows association; causation requires evidence of mechanism and control. Experimental design and controls help establish causal relationships.

Directional community change over time after disturbance or new habitat. Involves predictable stages from pioneer to climax species.

Succession beginning on bare substrate with no soil present. Requires soil formation before plant establishment can occur.

Succession after disturbance where soil and seed bank remain. Faster than primary succession due to existing soil infrastructure.

Early colonizer that tolerates harsh conditions and initiates soil formation. Examples include lichens on rock and grasses after disturbance.

Lichens and mosses colonizing bare rock with minimal soil. These organisms break down rock to create the first soil.

Rapid regrowth from surviving roots and existing soil nutrients. Shows secondary succession utilizing pre-existing soil resources.

An event that disrupts community structure and resource availability. Can be natural (fire, flood) or human-caused (logging, pollution).

Ability to recover structure and function after disturbance. Measured by speed and completeness of recovery processes.

Low dissolved oxygen levels that stress or kill aquatic organisms. Results from algal decomposition consuming dissolved oxygen rapidly.

Increase in toxin concentration at higher trophic levels. Fat-soluble toxins accumulate through predator-prey relationships.

Top predators show highest concentrations of persistent pollutants. Demonstrates toxin concentration increasing up food chains.

Toxin buildup within an organism over time. Occurs within individual organisms, unlike biomagnification across levels.

Maximum population size an environment can sustainably support. Determined by resource availability and environmental constraints.

Rapid increase followed by sharp decline (crash). Population exceeded $K$ then crashed due to resource depletion.

Resource or condition that restricts population growth or distribution. Could be food, water, space, or any essential resource.

Reduced gene flow and increased local extinctions in isolated patches. Small patches cannot support viable populations long-term.

Non-native species that spreads and causes ecological or economic harm. Lacks natural predators or competitors in new environment.