Bio 125 Exam 3 Ch 23 Marine Ecology

Marine Ecology

Ecology

The interaction between organisms and their environment.

Population

All individuals of the same species living together.

Community

All populations of organisms of different species living in a defined area.

Habitat

The physical place where an organism lives.

Ecological niche

All the resources (biotic and abiotic) an organism uses for survival, growth, and reproduction.

Limiting resources

Resources that affect the growth of a population.

Examples of limiting resources

food and nutrients, physical factors (light, salinity, substrate), space (habitat), oxygen and carbon dioxide, parasites and other symbionts.

Carrying Capacity

The maximum number of individuals that any habitat can support.

Ways that species interact

competition, predator-prey interactions, symbiosis

competition

occurs when 2 different species use the same limiting resource they both need for survival.

Intraspecific competition

organisms compete with members of their own species.

Interspecific competition

organisms compete with members of other (different) species.

Outcomes of interspecific competition

One species excludes the other (competitive exclusion) or they coexist (resource partitioning) by sharing a resource by becoming specialized (eating a particular food, feeding at different times).

3 types of symbiosis

mutualism, commensalism, parasitism

Mutualism

both species benefit (ex: cleaning associations, zooxanthellae and corals).

Commensalism

One species benefits with no apparent effect on the other (barnacles living on whales).

Parasitism

One species benefits and the other is harmed (tapeworms in the guts of whales).

Facultative symbiosis

If partners can live free without one another.

Obligate symbiosis

If a partner can’t survive without the other partner.

Symbiont and host

The smaller partner is the symbiont and the larger partner is the host.

Predation

One species (predator) kills another (prey) for food.

Herbivory

An organism (herbivore) that eats seaweeds or plants.

trophic structure

energy flows through an ecosystem

primary producers

Autotrophs that make food, base of the trophic pyramid

consumers

heterotrophs that feed on food made by primary producers. (predators at the top of the food pyramid)

pyramid of energy

On average, about 10% is transferred to the next level of the food chain.

benthos

live in or on the bottom, sessile or move about on the bottom.

zones within benthic zone

intertidal zone, subtidal zone, deep sea

intertidal zone

between high and low tide, exposed at least once a day

subtidal zone

below the low tide level to edge of continental shelf (shelf break), always submerged.

deep sea

bathyal, abyssal, and hadal zones beyond shelf break.

Pelagic organisms

live in the water column; plankton (drift with currents) and nekton (swim to oppose currents)

zones within pelagic zone

epipelagic zone, mesopelagic zone, bathypelagic, abyssopelagic, and hadopelagic zones

epipelagic zone

from surface to 100-200 m, plenty of sunlight for primary production.

mesopelagic zone

extends from lower limit of epipelagic to about 1000 m, reduced light

bathypelagic, abyssopelagic, and hadopelagic zones

deep sea zones where light does not penetrate

Carbon cycle

the natural process by which carbon atoms are recycled between the atmosphere, oceans, land, and living organisms. Carbon moves through the cycle via processes like photosynthesis, respiration, and decomposition.