Chapter 56 Conservation Biology and Global Change Flashcards
Which location has some of the greatest concentrations of species?
Tropical forests
What is conservation biology?
The conserving/saving and preserve biological life
What are the many fields that consists of conservation biology? (5)
- ecology
- physiology
- molecular biology
- genetics
- evolutionary biology
Earth’s biodiversity is being threatened by what?
Human activities
What are the 3 main components of biodiversity?
- genetic diversity
- species diversity
- ecosystem diversity
What is genetic diversity comprised of?
Genetic variation w/in a population and b/w populations
What is an endangered species?
Species in danger of becoming extinct throughout all or a significant portion of its range
What is a threatened species?
Species that are likely to become endangered in the foreseeable future
What is species diveristy?
Variety of species/organisms in an ecosystem or throughout the biosphere
What reduces ecosystem diversity?
Human activities as well
Why are species related to agricultural crops important?
- A lot of our medicine and improved genetically modified crops help populationa
What are ecosystem services?
Services that encompass all the processes thru which natural ecosystems and their species help sustain human life
What are some examples of ecosystem services? (4)
- Purification of air and water
- Detoxification and decomposition of wastes
- Cycling of nutrients
- Moderation of weather extremes
What are the 4 major threats to biodiversity?
- habitat loss
- introduced species
- overharvesting
- global change
What are introduced species?
Species are those that humans move from native locations to new geographic regions.
How are introduced species able to increase rapidly?
B/c of the lack of their native predators, parasites, and pathogens
What is overharvesting?
Human harvesting of wild plants or animals at rates exceeding the ability of populations of those species to rebound
What kind of organisms are vulnerable to overharvesting?
Large organisms with low reproductive rates
Example: elephants
What has decreased wild fish populations?
Overfishing
Example: North Atlantic bluefin tuna sharply decreased by 80% in ten years
What does global change include? (3)
- alterations in climate
- atmospheric chemistry
- broad ecological systems
What does acid precipitation contains? (2)
Contains sulfuric acid and nitric acid from the burning of wood and fossil fuels
What can air pollution from one region result in?
Can result in acid precipitation downwind
Can extinct species be resurrected?
Potentially thru cloning technology if frozen tissue is available
What does population conservation focus on? (3)
- population size
- genetic diversity
- critical habitat
What are the two main approaches biologists follow for conservation and the population/species level?
- small population approach
- declining population approach
What does the small population approach study?
Studies processes that can make small population become extinct
What is the key factor of extinction vortex?
- Loss of genetic variation necessary to enable evolutionary responses to environmental changes
What are small populations prone of?
Inbreeding and genetic drift –> leads to extinction vortex
What is the minimum viable population (MVP)?
Minimum population size at which a species can survive
What is effective population size?
Population size based on the population’s breeding potential
helps to estimate the minimum viable population
What is the effective population size estimated by?
N_e = (4N_fN_m)/(N_f + N_m)
where Nf and Nm are the number of females and the number of males, respectively, that breed successfully
N_e is the effective population size
What is the declining population approach?
An approach that focuses on threatened and endangered population that show a downward trend, regardless of population size
emphasizes the environmental factors that caused the population to decline
What are the steps of the declining-population approach? (5)
- Confirm that the population is in decline
- Study the species’ natural history
- Develop hypotheses for all possible causes of decline
- Test the hypotheses in order of likeliness
- Apply the results of the diagnosis to manage for recovery
What does conserving species often requires? (think of conflict)
Resolving conflicts b/w habitat needs of endangered species and human demands
What are defining features of landscapes?
Boundaries or edge b/w ecosystems
What is a movement corridor?
A narrow strip of habitat connecting otherwise isolated patches
What does the movement corridor promote? (2)
What is a disadvantage of the movement corridor?
Promotes dispersal and help with sustaining populations
- Can facilitate the spread of disease b/w populations
What is a biodiversity hot spot?
A relatively small area with a great concentration of endemic species and many endangered and threatened species
What are nature reserves?
Biodiversity islands in a sea of habitat degraded by human activity
must consider disturbances as a functional component of all ecosystems
What are the 2 approaches for a nature reserve
- One argument for large reserves is that large, far-ranging animals with low-density populations require extensive habitats
- Smaller reserves may be more realistic and may slow the spread of disease throughout a population
What is a zoned reserve?
A reserve model that recognizes that conservation often involves working in landscapes that are largely human dominated
What does a zoned reserve include? (2)
- relatively undisturbed areas
- modified areas that surround them and that serve as buffer zone
What is urban ecology?
Examination of organisms and their environment in urban settings
What are some human caused changed in the environment? (4)
- nutrient enrichment
- accumulation of toxins
- climate change
- ozone depletion
What is critical load?
The amount of added nutrients that can be absorbed by the plants without damaging ecosystem integrity
How does agriculture affects nutrients in the soil?
Agriculture removes/depletes nutrients in the soil
- Fertilizers add nitrogen and other nutrients back into the agricultural system
What happens if nutrients exceed the critical load?
Nutrient will leach into groundwater or run off into aquatic ecosystems
What is biological magnification?
Concentration of toxins at higher trophic levels where biomass is lower
What is the greenhouse effect?
CO2, water vapor, and other GHGs reflect infrared radiation back toward the earth.
What is assisted migration?
Translocation of species to a favorable habitat beyond its native range
What are some ways to reduce greenhouse gases? (4)
- reducing deforestation
- reducing energy needs
- converting to renewable source of energy
- stabilizing CO2 emissions
What is the ozone layer?
A protective layer that covers life on earth against damaging effects of UV radiation
What is destroying the atmospheric ozone?
Chlorofluorocarbons (CFCs) from human activity; decreases amount of ozone in the atmosphere
What is sustainable development?
A development that meets the needs of people today without limiting the ability of future generations to meet their needs
What does sustainable development require? (4)
Connections b/w
- life sciences
- social sciences
- economics
- humanities
