1 / 38

Community Ecology

Community Ecology. Chapter 54. Interspecific Interactions. Competition --/-- Competitive exclusion Ecological Niches (Habitat-address; niche-profession) Resource partitioning-allows similar species to coexist in a community Fundamental niche-potential

guri
Télécharger la présentation

Community 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. Community Ecology Chapter 54

  2. Interspecific Interactions • Competition --/-- • Competitive exclusion • Ecological Niches (Habitat-address; niche-profession) • Resource partitioning-allows similar species to coexist in a community • Fundamental niche-potential • Realized niche-actual-may be result of interspecific competition

  3. Character Displacement • Tendency for characteristics to diverge more in sympatric pop of 2 species than in allopatric pop

  4. Predation +/-- • Can be animal eating plant tissues • Defensive adaptations • Cryptic coloration

  5. Aposematic coloration-warning

  6. Batesian mimicry-harmless or palative looks bad

  7. Mullerian mimicry • 2 unpalatable species look alike

  8. Herbivory +/-- Plants have chemical toxins, spines, thorns ex strychnine, nicotine, selenium toxins Herbivores-special adaptations • Insect-chemical sensors • Sense of smell • Specialized teeth • Length of digestive systems

  9. Symbiosis • Parasitism +/-- • Mutualism +/+ obligate; facultative • Commensalism +/0

  10. Species Diversity • Species richness • Relative abundance

  11. Shannon diversity (H) • Index based on species richness and relative abundance

  12. Trophic structure • Food Chain

  13. Food Webs (Elton 1920s)

  14. Limits on length of foodchain • Energetic hypothesis-inefficiency of energy transfer -10% rule • Dynamic stability hypothesis-long food chains are less stable than short ones-population fluctuations at lower trophic levels are magnified at higher levels • Also-carnivores tend to be larger at successive trophic levels-can’t get enough food to meet needs

  15. Dominant species • Most abundant-have the highest biomass • Exert a powerful control • Are they are competitively superior in exploiting limited resources? • Are they are most successful at avoiding predation?-would explain effect of invasive species…

  16. Invasive pressure • American Chestnut • Before 1910-40% of US trees-fungal disease- Chestnut blight-killed all the trees-oak, hickory replaced; mammals, birds ok, but 7 species of moths and butterflies became extinct

  17. Keystone species

  18. Foundation species • Ecosystem “engineers” • Affect by causing physical changes in the environment • Ex beavers • Facilitators-may help other species

  19. Models of organization • Bottom up VH • NVHP • Top down VH • NVHP Trophic Cascade • Biomanipulation-prevent algal blooms by adding consumers rather than chemicals

  20. Disturbance • Influences species diversity and composition • Storms, waves, fires, freezing, drought, • Moderate disturbance can foster greater diversity than low or high levels

  21. Ecological succession • Species are replaced by other species • Primary • Secondary • Climax community

  22. Island Equilibrium Model

  23. Detritivores • Return nutrients to the soil • Law of conservation of mass

  24. Aquatic Ecosystem • Light limitation • Nutrient limitation • Eutrophication

  25. Biomass-dry mass

  26. Phytoplankton continually replace their biomass at such a rapid rate, they can support a biomass of zooplankton bigger than their own biomass.

  27. The Green World Hypothesis • Terrestrial herbivores are held in check by a variety of factors.

  28. Transitional Page

  29. Productivity • GPP-gross primary production • NPP-net primary production • NPP=GPP – R(autotrophic respiration) • Primary production • in aquatic is mostly affected by light and nutrients-N and P • Eutrophic-nutrient rich • On land-temp and water • evotranspiration

  30. Biogeochemical cycles

  31. Nitrogen cycle

  32. Additional Terms • Bioremediation-use of organisms to detoxify polluted areas • Bioaugmentation-add desirable species such as nitrogen fixers • Biodiversity (3 Levels)-genetic diversity, species diversity and ecosystem diversity • Threats: habitat loss, introduced species, over-harvesting, global change

  33. Population conservation • Focuses on: • Population size • Genetic diversity • Critical habitat

  34. MVP • Minimum Viable Population • Extinction Vortex

  35. Landscape and regional conservation • Habitat fragmentation • Movement corridors • Biodiversity hot spot-small area with an exceptional concentration of endemic species

  36. Human Actions • Agriculture-nutrient cycling-take it out of soil or too much in water • Acid precipitation • Biological magnification • Greenhouse effect • Global warming • Ozone layer

  37. Elements www.animationfactory.com

More Related