1 / 16

Ch. 52 - Population Ecology

Ch. 52 - Population Ecology Dynamic biological processes influence population density, dispersion and demography Life history traits are products of natural selection The exponential model describes population growth in an idealized, unlimited environment

kelvin
Télécharger la présentation

Ch. 52 - Population Ecology

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Ch. 52 - Population Ecology Dynamic biological processes influence population density, dispersion and demography Life history traits are products of natural selection The exponential model describes population growth in an idealized, unlimited environment The logistic growth model includes the concept of carrying capacity Populations are regulated by a complex interaction of biotic and abiotic influences Human population growth has slowed after centuries of exponential increase

  2. Population - a group of individuals of a single species living in the same general area Boundaries can be natural or arbitrary Density - number of individuals per unit area or volume Birth and immigration Death and emigration Dispersion - pattern of spacing among individuals within the boundaries of the population Clumped - most common Uniform - Random - most common; individuals aggregated in patches unpredictable spacing; position of each individual is independent of other individuals evenly spaced; may result from direct interactions between individuals in the population

  3. Demography - study of vital statistics of populations and how they change over time Life Tables - age specific summaries of the survival pattern of a population Study a cohort from birth to death

  4. Survivorship Curves - a graphic way of representing the data in a life table few offspring, good care constant death rate Lots of offspring, little to no care

  5. Reproductive tables - fertility schedule, age-specific summary of the reproductive rates of the population

  6. Big-bang reproduction Semelparity - semel = once, parito = to beget Repeated reproduction Iteroparity - itero = to repeat One better than the other? Ultimately, better when the environment is best suited for offspring

  7. dN = rmaxN dt r - per capita rate of increase N - population size t - time interval Exponential growth

  8. S shaped J shaped

  9. dN = rmaxN (K-N) Logistic Model dt K r - per capita rate of increase N - population size t - time interval K - carrying capacity - max population size that a particular environment can support Real populations??

  10. Density-Dependent Population Regulation Competition for Resources Territoriality Health Predation Toxic Wastes Intrinsic Factors

  11. Population Dynamics - focuses on complex interactions between biotic and abiotic factors that cause variation in population size Stability and Fluctuation Metapopulations (group of linked populations) and Immigration

  12. Population Cycles

  13. Human Population Growth

  14. Ecological footprint - aggregate land and water area appropriated by each nation to produce all the resources it consumes and to absorb all the waste it generates Ecological capacity - actual resource base of each country Ex: US: footprint of 8.4 ha per person, but only 6.2 ha per person of available ecological capacity

More Related