Quiz 4 Flashcards
The part of the sea floor that lies between high tide and low tide is called the ______ _____
intertidal zone
Describe intertidal zones
- Extreme environment; floods and dries out frequently
- The best understood
Describe rocky intertidal zones
- Found in areas with steep coastlines
- Occur in areas that have recently uplifted coastlines
- Limestone is common
- Epifaunal communities are present that attach to the surface of the rocks and cause bioturbation
What are the challenges for organisms living in rocky intertidal zones?
1) Water loss, which is overcome by:
- Mobility
- Having protective covering
2) Temperature changes, which is overcome by:
- Mobility
- Shell color adaptations
3) Wave shock, which is overcome by:
- Attaching strongly to the surface; holdfasts
Describe byssal threads in domingo mussles
Byssal glands secretes a fluid, the fluid hardens to form byssal threads, and the mussel is now attached to a rock. The mussel can detach from the rock by secreting enzymes
What are some adaptations for rocky intertidal zones?
1) Byssal threads
2) Suction cups (clingfishes and gobies)
Describe the general characteristics of the organisms that live in the intertidal zone
- Low profile
- Flexible body
- Grow in dense groups
What is the primary limiting factor of the intertidal zone?
Competition for space; the fastest moving or growing organisms win
Describe the vertical tide zones
- High tide zone: spends most of the time above water
- Mid tide zone: spends about half the time underwater and half the time above water
- Low tide zone: spends most of the time under water
Describe the low tide zone
-Fish, sea anemones, sea urchins, seaweeds, and sponges
Describe the mid tide zone
- Exposed half of the time and flooded half of the time
- Barnacles, chitons, and mussels
- Too harsh of an environment for species like anemones
Describe the high tide zone
- Exposed most of the time
- Lichens and snails
Describe feeding in the sandy intertidal
- Detritus is the main food source
- Organisms are either:
1) Deposit feeders: eat detritus in sediment
2) Suspension feeders: feed on particles suspended in the water
Describe lug worms
They have special hemoglobins that can transport minutes of oxygen
Describe mangrove forests
- Generally only occur in subtropics and tropics
- In protected coasts
- Trees and shrubs are facultative halophytes, which means they can tolerate salty environments and anaerobic soil conditions.
- Typically live in or near water
List and describe the 4 species of mangrove tree from closest to the ocean to furthest
- Red mangroves: most common, in the daily low tide zone, vivipary, prop roots, salt excluder
- Black mangroves: in daily high tide zone, has roots that grow upwards called pneumataphors, salt excreter.
- White mangroves: not flooded as often, salt excreter
- Buttonwood: not flooded as often
Define vivipary
When a plant’s embryo remains attached until it’s dropped
Food webs in mangrove environments are primarily ______
Detrital
Describe salinity adaptations of mangroves
Salt excluders= roots filter out 99% of the salt (red mangrove)
Salt excreters: release salt from the leaves (black and white mangroves)
List the 4 primary functions of mangroves
1) Rotting leaves provide organic matter
2) Roots control erosion
3) Prop roots provide habitats for juveniles and substrate for critters
4) Form rich, densely packed sediment
True or false: Mangroves are nurseries for fishes like barracuda
True
In the 200-plus years since the industrial revolution began, the concentration of carbon dioxide (CO2) in the atmosphere has increased due to human actions. During this time, the pH of surface ocean waters has fallen by ___ pH units, which is a _____% increase in acidity.
0.1; 30%
The ocean absorbs about _____ of the carbon dioxide (CO2) that is released in the atmosphere.
30%
The ocean’s average pH is now around ____, which is basic (or alkaline), but as the ocean continues to absorb more CO2, the pH decreases and the ocean becomes more acidic.
8.1
What organisms are especially impacted by ocean acidification?
Organisms like oysters and corals that make hard shells and skeletons by combining calcium and carbonate from seawater
The pteropod’s shells will eventually ______ if we continue to let the ocean waters get more acidic
dissolve
Researchers have already discovered severe levels of pteropod shell dissolution in the _____ Ocean
Southern Ocean
The ability of some fish, like _____, to detect predators is decreased in more acidic waters.
clownfish
While some species will be harmed by ocean acidification, ____ and _________ may benefit from higher CO2 conditions in the ocean
algae and seagrasses
Estimates of future carbon dioxide levels, based on business-as-usual emission scenarios, indicate that by the end of this century the surface waters of the ocean could have a pH around 7.8. The last time the ocean pH was this low was during the middle _______, 14-17 million years ago
Miocene
Increasing ocean heat content is contributing to what 3 main things?
1) Sea level rise
2) Ocean heat waves and coral bleaching
3) Melting of ocean-terminating glaciers and ice sheets around Greenland and Antarctica.
True or false: Heat already stored in the ocean will eventually be released
True
Averaged over the full depth of the ocean, the 1993–2020 heat-gain rates are ___-___ watts per square meter.
0.58-0.78
The main source of ocean heat is _______
sunlight
More than ___ percent of the warming that has happened on Earth over the past 50 years has occurred in the ocean
90
_______ ions are the building blocks for many species to build their shells
carbonate
