AP Environmental Unit 2 Flashcards Biodiversity.

What is biodiversity?

The variety of life on Earth — includes species, genetic, and ecosystem diversity.

What is species diversity?

Number of different species in an ecosystem and how evenly individuals are distributed.

What is genetic diversity?

Variety of genes within a species; higher diversity = better survival and adaptation.

What is ecosystem diversity?

Variety of ecosystems in a region (forests, deserts, wetlands, etc.).

Difference between richness and evenness?

• Richness: Number of species.

• Evenness: How evenly individuals are spread among species.

What are ecosystem services?

Benefits humans get from nature (4 types: provisioning, regulating, cultural, supporting).

What are provisioning services?

Products from nature — food, water, wood, medicine.

What are regulating services?

Nature controls conditions — climate regulation, flood control, pollination, water purification.

What are cultural services?

Non-material benefits — recreation, spiritual, aesthetic, tourism.

What are supporting services?

Basic ecosystem processes — nutrient cycling, soil formation, photosynthesis.

What is habitat fragmentation?

Splitting ecosystems into smaller pieces — reduces biodiversity and isolates species.

What does the Island Biogeography Theory say?

Large, nearby islands have more species; small, isolated islands have fewer.

What are edge effects?

Changes at habitat boundaries (more sunlight, wind, predators); often harm interior species.

What is ecological tolerance?

Range of conditions (temp, pH, light) a species can survive in.

Examples of natural disruptions?

Volcanoes, fires, floods, droughts — can change ecosystems and biodiversity.

What is adaptation?

Traits that help a species survive and reproduce in its environment.

What is evolution in environmental science?

Changes in a population’s genetic makeup over time; can increase survival.

What is ecological succession?

Gradual change in ecosystems over time — primary (new land) or secondary (after disturbance).

What is a keystone species?

Species that has a big effect on ecosystem balance (e.g., wolves, bees).

What is an indicator species?

Species that show ecosystem health (e.g., frogs = water quality).

What are invasive species?

Non-native species that spread fast and harm native ecosystems.

What is an endangered species?

Species close to extinction — often due to habitat loss, pollution, or overhunting.

Main human threats to biodiversity?

HIPPCO — Habitat loss, Invasive species, Pollution, Population growth, Climate change, Overexploitation.

2 main laws protecting biodiversity?

• Endangered Species Act (1973) – protects species & habitats in U.S.

• CITES (1975) – global treaty banning trade of endangered species.

What is a biodiversity hotspot?

Area with high species diversity under threat from humans.

How to identify ecosystem services on the exam?

Match the example to the 4 types:

• Food = Provisioning

• Water filtration = Regulating

• Hiking = Cultural

• Nutrient cycling = Supporting

What two factors affect island biodiversity?

Size (bigger = more species) and distance from mainland (closer = more species).

What happens when habitats are fragmented?

Species lose territory → biodiversity drops → more edge effects.

Why are edge effects bad for some species?

Edges have more light, wind, and predators — interior species can’t handle it.

How does tolerance affect survival?

Species survive only within their tolerance range; too much stress = death or migration.

Difference between adaptation and natural selection?

• Adaptation: Helpful trait.

• Natural Selection: Process that chooses which traits help survival.

How to tell primary vs. secondary succession apart?

• Primary: No soil (volcano, glacier).

• Secondary: Soil already there (fire, flood).

What happens if a keystone species disappears?

Whole ecosystem balance collapses; food webs change drastically.

What do CITES and ESA do?

• CITES: Stops international trade of endangered species.

• ESA: Protects species and their habitats in the U.S.