All Flashcards
Define biodiversity.
The variety of life in a particular habitat or ecosystem.
What is species diversity?
The total number of different species in an ecosystem.
Define species richness.
The number of different species present in an ecosystem.
What is species evenness?
How evenly distributed the species are in an ecosystem.
Define genetic diversity.
The variety of genes within a species.
What are alleles?
Different versions of a gene.
Define phenotypes.
The physical traits that result from genes.
What are ecosystem services?
The benefits humans get from the natural world.
Define ecological tolerance.
The range of conditions that a species can survive in.
What is ecological succession?
The process of ecosystem recovery after a disturbance.
Define pioneer species.
The first species to colonize a disturbed area.
What is primary succession?
Succession that starts with no soil.
Define secondary succession.
Succession that starts with soil already present.
What are the general steps of ecological succession?
Disturbance, colonization by pioneer species, development of intermediate species, establishment of climax community.
Describe primary succession.
Begins with bare rock, pioneer species (lichens) break down rock, soil formation, small plants, larger plants, eventually a forest.
Describe secondary succession.
Begins with existing soil, seeds germinate, grasses and shrubs grow, fast-growing trees, eventually a forest.
What are the effects of low species evenness?
An ecosystem may be less resilient to environmental changes and more susceptible to disease or invasive species.
What are the consequences of losing ecosystem services?
Reduced access to clean water, food shortages, increased climate instability, and loss of cultural and recreational opportunities.
What are the effects of volcanic eruptions on ecosystems?
Destruction of existing vegetation, alteration of soil composition, and potential for long-term climate change.
How does climate change affect ecological tolerance?
Species may be forced to migrate, adapt, or face extinction if their tolerance limits are exceeded.