11 Human Impacts and Conservation Free Online FlashCards

What is a population?

A group of individuals of the same species living in the same area.

Which four factors change population size?

Births, deaths, immigration, and emigration.

How can habitat fragmentation threaten populations?

It divides habitat into smaller patches, reducing available space and resources. Isolated populations are more vulnerable to local extinction and may lose genetic diversity.

What makes harvesting of a population unsustainable?

Overharvesting removes organisms faster than their populations can replace them.

How can pollution affect organisms?

Pollution can injure or kill organisms, reduce reproductive success, or change food availability and suitable habitat.

How can climate change affect species’ survival and reproduction?

It can shift the places and seasons where organisms can survive and reproduce; species unable to move or adapt quickly enough may decline.

How can invasive alien species harm native species?

They may prey on native species, compete with them, or spread disease.

What kinds of variation does biodiversity include?

Biodiversity is variation among genes, species, and ecosystems.

What are the main direct human-driven pressures on biodiversity?

Land- and sea-use change, direct exploitation, climate change, pollution, and invasive alien species.

How can fertilizer runoff harm aquatic life?

Excess nutrients can encourage algal growth; when algae decompose, dissolved oxygen can decline and aquatic life can be harmed.

What is an ecosystem?

An ecosystem includes the organisms in an area and the physical environment with which they interact.

Why can losing species with key ecological roles disrupt an ecosystem?

Reducing pollinators, seed dispersers, or decomposers can affect how an ecosystem functions.