Section 2

Large Marine

Ecosystems of the

world

ObjectivesTo understand relationships between

organisms within ecosystemsTo identify the connection between

environment, biodiversity and ecological niches

ReviewBinomial nomenclature created by Linneaus

in the mid-1700sEach species has a two part name1st – generic name (genus)2nd – specific name (species)

Terms to Know!Term Definition Example

Habitat Place where organisms live

Ecological Niche

The role of an organism within an ecosystem

Species A group of similar organisms that can interbreed and produce fertile offspring

Population

Organisms of the same species, living in the same area

Community

All the different species living in a habitat at the same time

Ecosystem

Living organisms and the chemical and physical factors which influence themWith a partner, take 2-3 minutes and come up with marine

examples of the terms listed above!

The ecosystem is affected by…

Biotic Factors

ECOSYSTEM

Abiotic Factors

Biotic Factors

ECOSYSTEM

AbioticFactors

The ecosystem is affected by…

What identifies an ecosystem:Biotic Abiotic

Living components of an ecosystem

Nonliving components of an ecosystem

Greek meanings:Bio = livingtic = of or pertaining toA = not; without

List 5 examples of each!

Marine Ecosystem Examplehttp://vimeo.com/28417462Rocky Shore – organisms living here, linked

together by flows of energy forming a food web, and their environmentAnimals must be able to adapt to changing

tides

Habitat ExampleHydrothermal vent – provides habitat for

species of tube worms

Population ExampleGhost crabs

(Ocypode saratan) living in the sandy shores

Mollusc community on a rocky shore (all different species of molluscs)

Species ExamplesSkipjack tuna

(Katsuwomus pelamis)

Red mangrove trees (Rhizophora mangle)

Ecological Niche ExamplesEcological niche of great white shark = top

predatorOrganisms which occupy similar niches will

tend to compete with each other forResources

Food Space in their habitat

BiodiversityTakes into account:

# of different species presentRange of habitats and ecosystems

Examples:

CORAL REEFSHigh biodiversity w/

many species present

SANDY SHORELow biodiversity w/ few species present

QuadratA square used in ecology and geography to

isolate a sample, usually about 1m2 or 0.25m2

Used to investigate the diversity of organisms in a suitable habitat (example: rocky shore or sandy shore)

Section 2 of Marine Ecosystems

Relationships between organisms

SymbiosisThe relationship between 2 different

organisms, where BOTH derive some benefit from the relationshipExamples

Corals and zooxanthellae Cleaner fish and grouper Chemosynthetic bacteria and tubeworms

ParasitismRelationship between organisms where 1

organisms benefits at the expense of the other (the host)

Parasites obtain nutrients from hostEctoparasites

Live on OUTSIDE of the host Example: Fish lice

Endoparasites Live INSIDE host (digestive system, attached to gills,

muscle tissue) Example: nematodes (roundworms) living in fish

Trophic Levels“feeding levels” in a food chain

or a food webProducers 1st trophic levelPrimary consumers2nd trophic

levelSecondary consumers 3rd

trophic level

More Terms…Term Definition

Producer Organisms which synthesize organic substances from simple organic compounds using light from the Sun

Consumer An organism that obtains its energy by feeding on other organisms

Primary Consumer

Feed on plant material (AKA Herbivore)

Secondary Consumer

Feed on herbivores ((AKA Carnivore)

Predator An animal that catches, kills, and eats another animal

Predator-Prey RelationshipFactors which affect # of predators in an ecosystem

Availability of food As the # of prey increases the # of predators increases As the # of prey decrease the # of predators decrease

http://vimeo.com/45154593

What would a graph of this relationship look like?With a partner create a graph? Be prepared to

explain your graph!

Predator-Prey Graph

ChemosynthesisSymbiotic bacteria convert H2S into organic

material: H2S + CO2 + O2 + H20 CH2O + H2SO4

Hydrogen sulphide is the primary energy source for hot vents and cold seeps

What is a Shoal?Large numbers of fish of the SAME species

and approximately the SAME size.Referred to as a ‘school’ when the group of fish

is swimming together in a coordinated way.

Benefits of Shoaling1. Hydrodynamic efficiency

Groups of fish save energy when swimming together

Benefits of Shoaling2. Predator avoidance:

a) Confusion effect: It is difficult for predators to pick out individual prey from groupsb) Many eyes effect as size of group increases, the task of scanning for predators can be spread out

Benefits of Shoaling3. Foraging Advantages : Time taken to

find food is decreased

4. Reproductive Advantages: Provides increased access to potential mates

Types of shoalersFish can be obligate or facultative shoalers:

Obligate – spends all their time shoaling or schooling and may become agitated when separated from the group (examples: tuna, herring, anchovy)

Facultative – shoal only some of the time, perhaps only for reproductive purposes(examples: Atlantic cod)

What is Succession?The gradual process of change that occurs in

community structure over a period of timeExample

SuccessionAs plant communities

change the animal communities change.

Succession at Hydrothermal VentsOne of the first animal species to inhabit the area

around a hydrothermal vent is the tube worm Tevnia.

Tevnia is replaced by the larger and faster growing tube worm Riftia.

Riftia tubeworms can grow up to two meters long. This

adult tubeworm that has been removed

from its white tube.

Tevnia are usually white, but this clump of worms is stained brown from iron in the vent fluids. The largest worm in this clump (with more white color) is a different species - a Riftia tubeworm.

Tevnia Riftia

What is a Whale Fall?When a whale dies, the carcass sinks to the

sea floor…this is known as a “whale fall”

The video below shows the gradual change in the community structure over time

Feast in the Deep

Boneworms on Dead Whales in Monterey Bay

Extreme & Unstable Environments

Tend to have LOW biodiversity! Example 1: Sand-easily dries out and

easily eroded by wind and water currents

Example 2: hydrothermal vents-high pressure, high temperature, few organisms adapted to these conditions

Stable & Favorable EnvironmentsTend to have HIGH biodiversity!

Example: Coral Reefs

Specialized Niche Generalized NicheNarrow range of food

requirementsLive in specific habitat

Example: Butterfly fishTerritorialLive closely w/corals and

anenomes

Exploit a wider range of food sources

Live in wider range of habitats

Ex: TunaMigratoryFeed on many different

species of fish

Why do habitats with high biodiversity tend to contain narrow ecological niches?

Each species has its OWN niche within the ecosystemWhat would happen if the niches overlapped?

INTERSPECIFIC COMPETITION and one species will die out!

Narrow niches reduce overlap and therefore reduce competition