1 / 17

Marine biodiversity

Marine biodiversity. Threats & Conservation. What is biodiversity?. Variety of life Species Genes Habitats . Three domains of life. Bacteria Archaea Eukarya All present in the ocean Bacteria, archaea are poorly known—few thousand or tens of thousand of species known

hana
Télécharger la présentation

Marine biodiversity

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. Marine biodiversity Threats & Conservation

  2. What is biodiversity? • Variety of life • Species • Genes • Habitats

  3. Three domains of life • Bacteria • Archaea • Eukarya • All present in the ocean • Bacteria, archaea are poorly known—few thousand or tens of thousand of species known • 230,000 or so marine plants and animals

  4. Diversity in different ocean zones • Pelagic – open ocean, upper 200 meters • Very low biodiversity • Dominated by floating animals in 4 groups, mainly copepods. • Only some 2000 species • 1-2 mm long • May be largest biomass

  5. Ocean biodiversity • Benthic habitats much more diverse • Includes coral reefs • Remember: benthic means bottom, not necessarily deep

  6. Food Oxygen Drugs Carbon storage Weather moderation Coastal protection (mangroves) The goods and services to the left have monetary value What about: Beauty Stewardship of nonhuman life Other? Value of biodiversityGoods and servicesThis is an IMPORTANT general idea: what goods or services does nature (in this case, the marine environment) provide?

  7. Marine food webs • Primary producers • Bottom of food web • Photosynthesizers • In ocean: tiny cyanobacteria that are responsible for 2/3 of the production (of biomass) • More generally: PHYTOPLANKTON, which means ``floating plants’’

  8. Marine food webs • Phytoplankton • Limited by nutrient availability • Nutrients such as iron • Iron fertilization as a technique to slow global warming

  9. Marine food webs • Next level: ZOOPLANKTON • Floating animals • Grazers • Then, various levels of larger grazing animals, culminating in large predators • Tuna, sharks, groupers, cod, etc

  10. Threats • Fisheries • Target top predators • Compare to terrestrial food webs • Climate change • Increasing temperature of sea water • More carbon dioxideincreased acidity • CO2 + H2O  carbonic acid

  11. threats • Pollution • Most pollutants ultimately enter the oceans • Oil • Nutrients – carried by rivers to the sea • Atmospheric deposition – mercury

  12. Most oil in the sea is from land-based operations • Including dumping oil when changing motor oil

  13. Nutrients: dead zones

  14. Atmospheric deposition: mercury • Burning fossil fuels • Especially coal-burning power plants • Incinerating municipal wastes • Found in common household products, including fluorescent bulbs, thermometers, batteries

  15. Atmospheric deposition: mercury • Mercury enters marine and freshwater systems • Concentration grows up the food chain • BIOACCUMULATION

More Related