chapter 14 · oceanography marine biology unit sections trophic levels and oceanic food webs...
TRANSCRIPT
Chapter 14
Oceanography Marine Biology Unit Sections
Trophic levels and Oceanic Food Webs
relationships
Oceanic Zones
Based upon light
Upon depth
Plankton
Size and niche
Benthos
Nekton
TROPHIC LEVELS Trophic levels are where an organism is on the food
chain (or food web)
Producers are Autotrophs that produce chemical food from Sunlight - on land these are plants
But tuna eat more than just one food and so do sharks
Sometimes the tables are turned
Food webs show all of the interconnectedness of organisms
Kelp forests are algae but don’t produce as much as Phytoplankton
Phytoplankton – Feed the Oceans and produce ½ of the world’s O2 PRODUCERS
Phytoplankton are eaten by Zooplankton (small animals)
Primary Consumers
Secondary Herbivores – Filter feeders
There’s plenty of food in phytoplankton for even big fish
And even really big mammals
Pyramids - Food, Biomass and /or Energy - every step gets 10% of the step before.
Producers Primary Consumers 1 °
Secondary Consumers 2 °
Tertiary Consumer 3 °
Quaternary Consumer 4 °
5 ° Consumer
What trophic level are we eating in the oceans?
Compare that to how we eat on Land
Producers and Primary Consumers
When was the last time that you ate a mountain lion?
This is Not Sustainable
Ecological relationships Parasitism Commensalism Mutualism
Parasitism – the host loses (sometimes dies) and the guest benefits.
Commensalism – The host gets nothing and the guest benefits
Mutualism – Both the host and Guest benefit (mutually)
Pelagic Zone- water environment
Neritic zone- pelagic zone above the continental shelf
Photic Zone 200m
Aphotic Zone Below 200 m (600 ft)
Oceanic zone- deep water away from the influence of land, further divided
into the photic and aphotic zone (without sunlight)
Benthic Zone- Seafloor environment (subdivided by depth) Intertidal Zone- between high and low tide
Subtidal Zone- below low water
Tropical Coral Reef Biome Abiotic Factors
Temperatures
Rainfall
Soil description
Biotic Factors Dominant Plants
Dominant Wildlife
Geographic Distribution
Mangrove Forest Biome Abiotic Factors
Temperatures
Rainfall
Soil description
Biotic Factors Dominant Plants
Dominant Wildlife
Geographic Distribution
Salt Marsh Biome Abiotic Factors
Temperatures
Rainfall
Soil description
Biotic Factors Dominant Plants
Dominant Wildlife
Geographic Distribution
Levels of Organization Species
Populations
Communities
Ecosystem
Biome – a group of ecosystems that have the same climate and similar dominant communities.
Ecological Methods 1 1. Observing what lives here?
2. Experimenting to test a hypothesis about the ecosystem.
3. Modeling long term phenomena with mathematical formulas to understand how it works.
Energy Flow - Sunlight is the main source of energy Producers- organisms that make their own food, also
known as autotrophs.
Include Plants, algae and some bacteria
Consumers – organisms that rely (eat) other organisms for their energy, also known as heterotrophs.
Include fungi and animals (you).
Food Chain The energy stored by producers can be passed through
an ecosystem along a food chain.
It is a series of steps in which organisms transfer energy by being eaten.
Each step is a TROPHIC LEVEL
Food Web The network of complex
interactions among all of the organisms in an area.
The connections form a web instead of a chain
Ecological Pyramids An ecological pyramid shows the relative amount of:
Numbers of individuals
Biomass of organisms
Amount of energy
In each trophic level
It decreases by 90% each step.
Cycles of Matter Biogeochemical Cycles
Matter (water, carbon, oxygen, etc) is recycled
Carbon Cycle CO2 in the atmosphere is taken up by plants and
turned into sugar.
The sugar is consumed by heterotrophs and turned back into CO2
Some plant matter gets buried and becomes fossil fuels
When this is burned, it goes back into the atmosphere (global warming)
Nitrogen Cycle N2 gas in the air (78 %) is not usable by plants or
animals
It is turned into fertilizer by lightening and nitrogen fixing bacteria
Plants turn it into proteins
Heterotrophs use the proteins and turn them into ammonia NH3
Plankton - Plankton are microscopic organisms that drift on the oceans' currents. They include organisms such as diatoms, dinoflagellates, krill, and copepods.
Phytoplankton Photosynthesize Zooplankton are little animals
Bacterioplankton - Bacterioplankton are the recyclers of the planktonic world. They are free-floating bacteria that break-down and recycle waste
material in the seas.
Microplankton (20-200 µm)
A region including the bottom of the sea
Animals and plants living on or within the substrate of a water body.
Benthic Organisms include: Burrowers Creepers Sessile organisms And some Swimmers
Mantis Shrimp
Creepers – worms, crustaceans
Benthic Swimmers
Benthic Sessile (don’t move)
Nekton – Organisms that can swim against currents. Cephalopods
Fish
Marine mammals
Reptiles