Marine EcosystemsEcology

Ecology- studies how organisms relate to each other and their environment Abiotic and Biotic Factors

Biotic- living (quantity and type of organism) Abiotic- non-living (temperature, wind, pH,

currents, minerals, sunlight, etc). Ecosystem- All the living and nonliving (biotic and abiotic) components in a defined area.Community- All the different living organisms in the ecosystem. Population- Group of the same species living and interacting within a communityHabitat- includes the area and conditions in which you find an organism. Microhabitat-exists on a very small scale Niche- organisms role in its habitat

Ecosystems in the Open Sea Neuston ecosystem (plankton that live afloat on the sea surface) Very thin layer (few mm) Receives maximum amount of sunlight Largest floating ecosystem- Sargasso Sea

o Sargassum- brown algae accumulates in the middle of the North Atlantic as floating mats. Continental Shelf Rarely exceeds 656’; s nutrients are kept in the photic zone. Highly productive ecosystem Upwelling Significant to open sea ecosystems because they bring nutrients from deep water to shallow more productive

depths Costal Ecosystems

Estuaries Exists where the tides meet rivers Trap and accumulate runoff sediments, so they are rich with nutrients and biologically productive Provide shallow sheltered water with a steady stream or nutrients Serve as nurseries for 75% of commercial fish species Salt Marshes Exist in estuaries and along the coast Halophytes- plants with adaptations that allow them to survive in salt water.

o Have stomata on leaves that allow it to draw in oxygen into its submerged parts. o Sacrificial leaves that serve as a storage area for excess salt and fall of when the slat load reaches a

certain point o Salt glands on leaves and stem excrete excess salt.

Mangrove Swamps Various adaptations allow them to live in salt water

o Grow above waterline on stilt-like roots, which allows oxygen to reach the roots Provide habitats for juvenile fish and invertebrates because of strong, tangled roots. Protect habitat and coasts from erosion Sea grasses Provide shelter Internal salinity is the same as the sea water Reproduce by releasing pollen into currents

Intertidal zones May be above waterline a times Adaptations help retain moisture Beaches Rich and productive ecosystem Acts a filter that processes compounds

entering the sea Sand protects coastline Reduce sedimentation caused by

coastal erosion Complex organisms live in submerged

beach sand o Meiofauna- Benthic organisms

that live in spaces between sand grains

Kelp and Seaweed Seaweed-red, green, and brown algae Kelp forest- very productive Coral Reefs Most productive ecosystem Threats to coral reefs

o Nutrients o Increased temperature is causing coral bleaching (Global Warming) o Competitive algae o Sedimentation o Coral Disease

Polar Ecosystems The Arctic Species found here have special adaptations

o Anti-freezing compounds in bloodo Low metabolism

Upwellings : Increased productivity because of nutrients being brought to the top Challenges to marine organisms:

o Reduced sunlight o Near freezing water

The Antarctic Largest nutrient-rich area on Earth Supports massive phytoplankton blooms

Deep-sea Ecosystems The Abyssal Zone Average temperature 2C No primary productivity (nutrients come from marine snow) Greatest diversity found in the meiofauna Whale Falls Place where dead whales come to rest on the deep ocean floor Hydrothermal Vents and Cold Seeps Home to chemosyntheitc organisms Hadal Depths- Ocean Trenches Makes up the deepest ocean depths Scientists know little because of limits of technology

o Few submersibles have been built that can descend safely into the zone o 1 manned trip has been made to the deepest known spot in the ocean.