CH8 Ecology

it was literally like pulling teeth trying to make this god send help

ecosystem

totality of the environment, including all the living (biota) and non living (abiotia) parts

biotic parts

living parts

• animals/plants

• bacteria/algae

• photosynthesis + respiration

• predation, scavenging, filtering

• food chains

abiotic parts

nonliving

• temperature

• salinity

• ocean currents, tudes, and waves

• turbulence

• inorganic nutrients

• SUNLIGHT IS THE MOST IMPORTENT

what does sunlight in the ocean restrict?

the range of photosynthesis, phytoplankton, and everything that eats phytoplankton

what are the ocean depths based on sunlight?

photic zone (0→100m)

dysphotic zone (100→500m)

aphotic zone (>500m)

which colors go the shortest and furthest down?

ultraviolet and reds have the least reach while blues have the highest reach but it all depends on how much sediment and small microscopic organisms are present in the water

pelagic provinces

1. epipelagic (0→200m)

2. mesopelagic (200→1000m)

3. bathypelagic (1000→2000)

4. abyssalpelagic (2000→6000m)

5. hadalpelagic (>6000m)

benthic provinces

1. littoral (high tide mark→low tide mark)

2. sublittoral (0→200m)

3. bathyal (200→2000m)

4. abyssal (2000→6000m)

5. hadal (>6000m)

same as pelagic except its the actual ground, not the water. littoral and sublittoral replace epi + meso pelagic

epipelagic zone characteristics

• upper 200m

• rich in oxygen

• turbulent waters

• warm waters

• rich in food supply

• photosynthesis heavy

• depleted in plant nutrients

• brightly lit

basically its bright and wavey and warm with tons of oxygen and photosynthesis

animals include regular fish, seahorses, dolphins, the copepod and planktons

mesopelagic zone characteristics

• 200→1000m down

• dimply lit (disphotic zone)

• colder water

• less food rich

• calmer waters

• less oxygen

• the oceans compost/nutrient regeneration layer

basically it is sadder than the epipelagic zone, its colder and has less food and oxygen but it is calmer, probably because everyone is too hungry to move idk

animals are the crested bigscale (ugly), barreleye (small w massive eyes), and viper/dragon fish (massive mouth)

bathy, abyssal, and hadalpelagic zone characteristics

• 1000m→sea floor

• contains 75% of living space in the ocean

• no sun at all

• oxygen rich

• bioluminescent stuff

• no food

• high water pressure

• super cold water

• crazy fish

a combo deal of the first two, has tons of oxygen but is super dark and really cold

animals are the angler fish, blobfish (my goat), basically all the really freaky ones with massive mouths and tiny eyes

bioluminescence

originates from luciferin molecule and oxygen to create oxy-lucoferin, mostly blue-green color but can be yellow, not found in mammals

an ecosystem is most accurately defined as containing what components?

abiotic and biotic

the oceans photic zone is how deep, on average?

100m (maybe)

the oceans photic zones depth is defined by what?

depth to which photosynthesis can occur

if you are a scuba diver very deep in the ocean, what is the dominant color of sunlight you are most likely to see?

blue

what are the pelagic biozones from the surface to the deep?

epi, meso, bathy, abyssal, hadal

what is the concentration of plant nutrients in the vertical direction?

depleted in the epipelagic, high concentration in the mesopelagic

why are plant nutrient concentrations high in the mesopelagic?

they are produced here by bacteria, by the decomposition of organic matter

why are plant nutrient concentrations low in the epipelagic?

they are consumed here by photosynthesis

large eyes found in many mid-water fish of the mesopelagic are an adaptation to what aspect of their environment?

low light

weak musculature in many mid and deep water fish of the mesopelagic and below are an adaptation to what aspect of their environment?

low turbulence and weak currents

littoral zone characteristics

• high tide→low tide

• daily dessication

sublittoral zone characteristics

• always under water

• starts at the low tide mark to the edge of the continental shelf (about 200m)

bathyal zone characteristics

• 200→2000m

• the continental slope

abyssal zone characteristics

• 2000→6000m

• >80% of the benthic environment

hadal zone characteristics

• >6000m down

• within oceanic trenches

• isolated environment with freaky creatures

neritic sediments

fine + coarse sands, hard rocks, heterogenous clamshells, pebbles, etc.

deep sea sediments

fine grained muds + silts

shallow benthos vs deep sea benthos

the shallow benthos is abundant in food, sunlight, and has fast currents while the deep sea benthos is the exact opposite of all of that

how is a lot of deep sea fauna fed?

by the organic matter falling due to gravity

what is the linnaean system of classification?

classification according to genetics

how are organisms sometimes classified?

by their role in the ecosystem (what do they eat, life cycle, where do they live, how do they move)

three domains of life

1. bacteria

2. eukaryotes

3. archaea (extremophiles)

five kingdoms

1. monera- bacteria and cyanobacteria

2. protista- single celled organisms with a true nucleus

3. chromista- plants

4. fungi- fungus

5. metazoa- animals

what are the classifications for how an organism moves?

plankton- floaters

nekton- swimmers

benthos- bottom dwellers

plankton classifications based on lifecycle

holoplankton = they are plankton for their whole life (diatom, copepod, jellyfish)

meroplankton = they are plankton for only part of their life (crabs)

autotrophic

produces its own food by photosynthesis (phytoplankton)

heterotrophic

consumes food produced by others (zooplankton)

diatomic acid

produced by some diatoms, like shellfish poisoning in humans

dinoflagellates

these little creatures that are free living, some have bioluminescence, most are mobile by the means of two flagella, usually about 50 micrometers

many produce toxins and accumulate in shellfish

coccolithophores

microscopic things that are photosynthetic with a CaCO3 wall, make up the white cliffs of dover, usually about 5 micrometers

bacterioplankton

bacteria in the epipelagic + photic zones, around 0.2-2 micrometers, most abundant “plant” on earth, dominant in calm subtropical gyres

zooplankton

live in the epipelagic to the seafloor, can range from microns to meters, heterotrophic, can be grazers or predators (range from microscopic things to jellyfish)

chaetognaths/arrow worms

voracious predators about 4cm in length with hooks in their mouth, found everywhere in the ocean

copepods

about 1-2 millimeters in length, grazers of diatoms

what is the Linnaean classification system based on?

genetic relatedness

plankton are organisms that float. why is a copepod, which can swim and propel itself through the water, classified as plankton?

because of its small size, it cannot swim very fast or far, so its location is determined by currents

which of the following types of plankton produce domoic acid, the toxin that causes amnesiac shellfish poisoning?

diaotms

which of the following types of plankton cause harmful algal blooms that can kill or poison other animals in the ocean or even humans?

dinoflagellates

a fish larvae is an example of what type of plankton?

meroplankton

siliceous sediment is found on seabeds overlying ocean waters that are rich in what type of plankton?

diatoms

calcium carbonate-rich sediment is found on seabeds overlying ocean waters that are rich in what type of plankton?

coccolithophorids THE COCC!!!

why are sessile, plank like macroalgae (seaweed) only found in littoral and sublittoral environments?

they require light to reach the ocean bottom, which only occurs in these two zones

why are abyssalpelagic fish lacking color in their skin?

the lack of sunlight in the deep sea makes skin color unnecessary because it cannot be seen

the seafloor is the ____ province while the water column is the ____ province?

benthic, pelagic

the ocean overlying the continental shelf is termed the ___ habitat and the ocean overlying the open ocean is the ___ habitat?

neritic, pelagic

if a fish is displaying countershading, why can it not be seen by a predator swimming underneath it?

the light underside of the prey fish causes it to blend into the light backgorund

why are abyssopelagic fish lacking sharp eyesight?

the lack pf sunlight in the deep sea makes acute vision unnecessary

how do abiotic factors like temp, salinity, sun, etc. control ecosystems?

by controlling the ranges of organisms and the rates of metabolisms (many marine organisms are cold blooded so their temp is determined by the environment around them)

eurythermal species

capable of withstanding rapid and extreme temp changes (organisms in tide pools)

stenothermal species

incapable of withstanding wide temp swings (deep sea creatures)

euryhaline

capable of withstanding rapid and extreme salinity changes

stenohaline

incapable of withstanding wide salinity swings

diffusion

random molecular motion results in the movement of substances from points of high concentration to low concentration

osmosis

diffusion but its only water and goes through a semipermeable membraned

osmoregulation

fish counteract the diffusion of water in/out of them by not drinking/drinking water