unit 1-4 : cumulative review

• Carbon sequestration


  Process of capturing and storing carbon dioxide from the atmosphere
• Carbon sink


  Natural or artificial reservoir that absorbs and stores carbon dioxide
• Carbon source

  Natural or artificial reservoir that releases carbon dioxide into the atmosphere
• Nitrogen cycle

  Process by which nitrogen is converted between its various chemical forms
• Fixation


  Conversion of atmospheric nitrogen into a form usable by plants
• Denitrification


  Conversion of nitrates back into atmospheric nitrogen
• Extinction

  The complete disappearance of a species from the Earth
• Adaptations


  Traits or characteristics that help organisms survive and reproduce in their environment
• Species survival

  Factors other than diversity that contribute to the long-term survival of a species
• Ecosystem services

  Benefits that humans receive from ecosystems, such as clean water, air, and food
• Provisional services: Ecosystem services that involve the production of renewable resources; goods taken from ecosystems or made from natural resources
• Regulating services


  Ecosystem services that control important ecological processes
• Supporting services

  Ecosystem services that are necessary for the production of all other ecosystem services
• Cultural services

  Ecosystem services that provide cultural, aesthetic, or recreational benefits
• Theory of Island Biogeography

  The study of the factors that affect species diversity on islands
• Primary succession


  The process of ecological succession that occurs in an area without soil
• Secondary succession


  The process of ecological succession that occurs in an area with existing soil
• Pioneer species


  The first species to colonize a barren or disturbed area
• Climax community


  The final stage of succession, characterized by a stable and diverse community of organisms
• Biodiversity


  The variety of life in a particular habitat or ecosystem
• Genetic diversity


  The variety of genes within a species
• Species diversity


  The variety of species within a community or ecosystem
• Ecosystem diversity


  The variety of ecosystems within a region
• Anthropogenic impacts


  Human activities that negatively affect biodiversity
• Species richness


  The number of different species in a community
• Species evenness


  The relative abundance of each species in a community
• Populations


  Groups of individuals of the same species that live in the same area
• Birth rate


  The number of births per 1,000 individuals in a population per year
• Death rate


  The number of deaths per 1,000 individuals in a population per year
• Age structure diagrams


  Graphical representations of the distribution of age groups in a population
• Total fertility rate


  The average number of children born to a woman in her lifetime
• Replacement level fertility rate


  The fertility rate at which a population replaces itself from one generation to the next
• Developing countries


  Countries with lower levels of industrialization and income
• Developed countries


  Countries with higher levels of industrialization and income
• Doubling time


  The time it takes for a population to double in size
• Percent change of growth

  The percentage increase or decrease in population size over a specific period of time
• Keystone species


  A species that has a disproportionately large effect on its environment relative to its abundance
• Generalist species


  A species that can survive in a wide range of environmental conditions and can eat a variety of foods
• Specialist species


  A species that has a narrow range of environmental conditions in which it can survive and a limited diet
• R-strategist


  A species that has a high reproductive rate and produces many offspring, but provides little parental care