Marine Biology: Deep-Sea Ecosystems Quiz
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Questions and Answers

What primary source of nourishment do many bottom-dwelling animals rely on?

  • Gathering falling food particles (correct)
  • Hunting larger prey
  • Active predation on schools of fish
  • Seeking shelter to avoid predators

What is a major feature of the marine environment that supports a diverse range of habitats for organisms?

  • Shallow coastal waters
  • Deep-sea trenches
  • Open water columns
  • The seabed (correct)

How do sediment deposits benefit certain marine creatures?

  • They give concealment and protection for burrowing creatures. (correct)
  • They promote rapid growth of coral reefs.
  • They enhance photosynthesis in algae.
  • They provide a food source for filter feeders.

What has been the impact of modern exploration techniques on our understanding of deep-sea biodiversity?

<p>They have rapidly increased knowledge of deep-sea benthos. (A)</p> Signup and view all the answers

Which of the following statements is true about biomass in relation to ocean depth?

<p>Biomass generally decreases with depth. (C)</p> Signup and view all the answers

What role do hydrothermal vent communities play in deep-sea ecosystems?

<p>They exhibit unique ecosystems due to extreme conditions. (D)</p> Signup and view all the answers

What determines the depth range at which benthic communities receive primary production?

<p>Water clarity (C)</p> Signup and view all the answers

What is one of the main reasons for the greater diversity of the benthic population compared to the pelagic population?

<p>Availability of hard surfaces and shelter (A)</p> Signup and view all the answers

Which organism is identified as an obligate commensal living alongside the hermit crab?

<p>Neanthes fucata (D)</p> Signup and view all the answers

What role does the barnacle Peltogaster paguri play in the hermit crab's ecosystem?

<p>It acts as a parasite on the hermit crab. (B)</p> Signup and view all the answers

Which animal uses the shell of the hermit crab as a substitute habitat rather than for protection?

<p>Porcellana platycheles (B)</p> Signup and view all the answers

What impact do environmental changes have on species within the community?

<p>They impact recruitment and mortality rates differently among species. (B)</p> Signup and view all the answers

Which organism is capable of boring into the shell of the hermit crab?

<p>Polydora ciliata (B)</p> Signup and view all the answers

What type of relationship does the hermit crab have with the polychaete worm N. fucata?

<p>Commensal (B)</p> Signup and view all the answers

What helps maintain the dynamic equilibrium within a community?

<p>Increased predation and competition among species. (C)</p> Signup and view all the answers

Which of these organisms typically uses the shell of a whelk for habitat?

<p>Pseudione spp. (A)</p> Signup and view all the answers

What is the primary method by which deep-living species obtain nutrients in the water column?

<p>Saprophytic feeding on dead materials (B)</p> Signup and view all the answers

Which of the following is associated with the production of marine snow?

<p>Aggregation of organic and inorganic particles (A)</p> Signup and view all the answers

What role do polysaccharides play in the formation of marine snow?

<p>They enhance the cohesion of particles. (D)</p> Signup and view all the answers

Which of the following is considered a primary producer in deep-sea ecosystems?

<p>Chemosynthetic bacteria (D)</p> Signup and view all the answers

How fast can aggregated marine snow particles sink through the water column?

<p>Up to 200 m per day (D)</p> Signup and view all the answers

What provides the basis for carbon fixation by chemosynthetic bacteria in abyssal sediments?

<p>Reduced inorganic metal compounds (D)</p> Signup and view all the answers

What is the significance of marine snow for deeper marine ecosystems?

<p>It serves as a food source for a variety of organisms. (C)</p> Signup and view all the answers

Which of the following organisms are known to benefit from the presence of marine snow?

<p>Microorganisms in the water column (A)</p> Signup and view all the answers

What is marine snow primarily linked to?

<p>Surface phytoplankton blooms (B)</p> Signup and view all the answers

What is a significant implication of marine snow for climate change?

<p>It facilitates the transfer of CO2 to deeper ocean levels. (D)</p> Signup and view all the answers

What term is used for a whale carcass that has reached the deep-sea floor?

<p>Whale fall (C)</p> Signup and view all the answers

Which organisms are primarily responsible for breaking down whale bones?

<p>Osedax worms (D)</p> Signup and view all the answers

How do scavengers benefit from whale falls?

<p>They obtain a concentrated food source. (A)</p> Signup and view all the answers

What type of bacteria utilizes sulfides released from decaying whale bones?

<p>Chemosynthetic bacteria (D)</p> Signup and view all the answers

Which of the following animals is NOT mentioned as a scavenger of whale falls?

<p>Eels (A)</p> Signup and view all the answers

How long can a large whale fall sustain a community of organisms?

<p>Many years (A)</p> Signup and view all the answers

What is the primary function of the tangled root-like lower body of the worms?

<p>To penetrate bone and dissolve it through acid secretion (D)</p> Signup and view all the answers

What role do symbiotic bacteria play in the nutrition of the worms?

<p>They transfer nutrients directly to the worms (C)</p> Signup and view all the answers

Which deep-sea invertebrates have been reported to utilize dissolved organic matter (DOM) directly?

<p>Deep-sea starfish and polychaetes (B), Suspension-feeding sponges and cnidarians (D)</p> Signup and view all the answers

How much of the energy required by the deep water starfish Plutonaster and the polychaete Tharyx is estimated to come from dissolved organic carbon?

<p>30% (B)</p> Signup and view all the answers

Which of the following factors increases the capacity of invertebrates to absorb DOM?

<p>A soft body and high surface area to volume ratio (B)</p> Signup and view all the answers

What is an important source of food for deep-sea benthic animals?

<p>Dissolved organic matter (DOM) (A)</p> Signup and view all the answers

Where is considerable DOM held in deep-sea sediments?

<p>In interstitial water (C)</p> Signup and view all the answers

Which marine invertebrate is specifically mentioned as utilizing symbiotic chemosynthetic bacteria?

<p>Giant tubeworms such as Riftia (B)</p> Signup and view all the answers

What is the primary function of sediment traps in marine research?

<p>To collect data on biogenic particle rain (C)</p> Signup and view all the answers

Which component of deep water sediment traps allows for the automatic collection of samples?

<p>Rotary collector with sampling bottles (B)</p> Signup and view all the answers

What characteristic makes kelp forests particularly significant as ecosystems?

<p>They provide a biologically generated habitat. (A)</p> Signup and view all the answers

What is the approximate height that Giant Kelp can reach?

<p>30 - 40 meters (C)</p> Signup and view all the answers

When were modern sediment traps first tested in deep water?

<p>1978 (C)</p> Signup and view all the answers

What is one method used alongside sediment traps in marine studies?

<p>Using time-lapse photography (B)</p> Signup and view all the answers

In which era were kelp forests recognized for their high productivity and biodiversity?

<p>Modern environmental research (B)</p> Signup and view all the answers

What design feature is used to prevent large objects from contaminating sediment traps?

<p>A baffle to keep large objects out (B)</p> Signup and view all the answers

In which zone do animal growths predominate while foliose algae are restricted to scattered patches due to low light levels?

<p>Upper circalittoral (D)</p> Signup and view all the answers

What ecological role does the bottom current play in benthic communities?

<p>It aids in the settlement of pelagic larvae on the seabed. (D)</p> Signup and view all the answers

Which factor is considered most crucial for community differences at abyssal depths?

<p>Hydrostatic pressure (C)</p> Signup and view all the answers

What is a potential effect of strong wave action on benthic communities?

<p>It can damage or displace animal growths. (C)</p> Signup and view all the answers

Which feature is essential for the richest benthic communities in the sublittoral zone?

<p>Moderate tidal water flow (B)</p> Signup and view all the answers

What significant challenge do bivalve molluscs face in sediment communities?

<p>Filtering out food from silt-laden water (D)</p> Signup and view all the answers

Which type of algae is often found at depths with little shading from kelp?

<p>Foliose algae (D)</p> Signup and view all the answers

What describes the composition of the community at greater depths beyond 20 meters?

<p>A mix of calcareous encrusting algae and animal growths (C)</p> Signup and view all the answers

What factor primarily influences the settlement behavior of Ophelia bicornis larvae?

<p>Type of sediment and organic coating (A)</p> Signup and view all the answers

What happens to the larvae of Ophelia bicornis when they encounter repellent sand?

<p>They swim away and search for new substrates (C)</p> Signup and view all the answers

What effect does washing sand samples with hot concentrated sulfuric acid have on Ophelia bicornis larvae behavior?

<p>Makes the sand neutral, losing attractive qualities (C)</p> Signup and view all the answers

Which sensory cue is NOT mentioned as a settling cue for larval organisms?

<p>Ability to detect sound (A)</p> Signup and view all the answers

What is a common characteristic of species that settle on substrates with high organic matter content?

<p>Increased chemical sensitivity to diffusing substances (C)</p> Signup and view all the answers

How long after being produced do Ophelia bicornis larvae begin to enter the deposit for metamorphosis?

<p>5 days (D)</p> Signup and view all the answers

What behavior do Ophelia bicornis larvae exhibit when exploring deposits?

<p>They engage in repeated exploration until finding suitable sand (C)</p> Signup and view all the answers

What type of larvae are attracted to organic substrates like wood?

<p>Pelagic larvae (B)</p> Signup and view all the answers

What are sediment traps primarily used for in marine research?

<p>Measuring biogenic particles falling throughout the year (D)</p> Signup and view all the answers

What is the main feature of modern sediment traps that allows for sample collection?

<p>A rotating carousel with automatic sealing mechanism (A)</p> Signup and view all the answers

Which group of organisms is primarily responsible for creating the physical framework of kelp forests?

<p>Kelp, specifically large brown seaweeds (A)</p> Signup and view all the answers

How deep can Giant Kelp grow, reaching heights similar to certain tropical trees?

<p>30-40 m (D)</p> Signup and view all the answers

What was a significant study that made use of sediment traps in the 1990s?

<p>The Joint Global Ocean Flux Study (C)</p> Signup and view all the answers

What design feature is included in deep-water sediment traps to prevent contamination by large objects?

<p>A baffle system (D)</p> Signup and view all the answers

In which year were modern sediment traps first tested in deep water?

<p>1978 (B)</p> Signup and view all the answers

What type of ecosystems do kelp forests exemplify in terms of productivity and biodiversity?

<p>Highly productive and biodiverse systems (B)</p> Signup and view all the answers

What aspect of the marine habitat classification for Britain and Ireland is emphasized in its compatibility?

<p>It is integrated with the EUNIS system. (C)</p> Signup and view all the answers

Which of the following communities did Petersen distinguish in his studies of marine benthic communities?

<p>Venus communities (B)</p> Signup and view all the answers

What was a significant limitation of the methods used by Thorson in classifying marine communities?

<p>Certain prominent organisms could appear in different ecological contexts. (B)</p> Signup and view all the answers

What are some of the key environmental factors that affect species distribution in marine communities, according to Thorson's observations?

<p>Temperature and salinity (D)</p> Signup and view all the answers

What type of sampling method did Petersen utilize in his investigations of marine benthic communities?

<p>Grab sampling (C)</p> Signup and view all the answers

In the context of marine benthic communities, what is a characteristic feature of the Venus community as identified by Petersen?

<p>It predominates in shallow sandy bottoms. (C)</p> Signup and view all the answers

What does the classification approach used by Thorson primarily emphasize in relation to community composition?

<p>The most prominent genera rather than species (D)</p> Signup and view all the answers

What factor complicates the classification of marine communities based on prominent species, as noted in the content?

<p>Certain species can exist in multiple habitats. (C)</p> Signup and view all the answers

What defines the size of meiofauna within marine ecosystems?

<p>Typically smaller than 0.5 mm (C)</p> Signup and view all the answers

Which organisms are considered prominent members of meiobenthos?

<p>Nematodes and harpacticoid copepods (B)</p> Signup and view all the answers

What role does meiofauna play in marine food webs?

<p>They serve as a vital early trophic link. (C)</p> Signup and view all the answers

What defines the microbenthos community in shallow waters?

<p>Small organisms living in algae and sediment. (A)</p> Signup and view all the answers

Which statement accurately represents the size range of meiofauna?

<p>From 0.063 mm to approximately 0.5 mm (D)</p> Signup and view all the answers

Where are permanent residents of the meiofauna typically found?

<p>In sediment from intertidal zones to deep ocean (D)</p> Signup and view all the answers

How do some meiofaunal species contribute to the overall ecosystem?

<p>By providing a link between bacteria and larger organisms (D)</p> Signup and view all the answers

What is the significance of sediment particle sizes for benthic communities in the deep sea?

<p>They influence the composition and biomass of animal communities. (B)</p> Signup and view all the answers

What is a key factor that influences the classification of benthic communities?

<p>Physical and chemical parameters (A)</p> Signup and view all the answers

Which parameter did Jones use to define shelf communities in the northeast Atlantic?

<p>Multiple factors including depth and salinity (D)</p> Signup and view all the answers

What aspect limits the effectiveness of classification systems for benthic communities?

<p>Species have fluctuating distributions and overlapping zones (B)</p> Signup and view all the answers

What modern advancement has contributed to the classification of benthic habitats?

<p>Computer technology enabling comprehensive data integration (A)</p> Signup and view all the answers

In benthic community classifications, what is typically abstracted from studies of overlapping distributions?

<p>Community composition (C)</p> Signup and view all the answers

How does the distribution of benthic species usually behave in relation to habitat changes?

<p>There are corresponding adjustments in species assemblage (D)</p> Signup and view all the answers

What aspect of deep-sea benthic communities is often characterized by transitional zones?

<p>Continuous changes in habitat characteristics (B)</p> Signup and view all the answers

What does the modern classification system for benthic habitats combine?

<p>Physical habitat and species approaches (C)</p> Signup and view all the answers

Flashcards

Benthic communities

Communities of marine organisms that live on or in the seabed.

Food supply (shallow water)

Abundant food in shallow waters due to primary producers like algae and phytoplankton.

Benthic food gathering

Organisms collect food particles and organic matter from sediment or currents.

Pelagic vs. Benthic

Open water marine creatures are less diverse than bottom-dwelling ones.

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Seabed habitats

The seabed offers various structures (hard surfaces, sediment) providing shelter and attachment points for marine life.

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Deep-sea Benthos

Deep-sea organisms; biodiversity not initially thought to be low (especially when including microbes).

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Biomass decrease with depth

The amount of living matter (biomass) typically decreases as water depth increases, away from land.

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Hydrothermal vent communities

Exceptions to the general trend of biomass decrease with depth, certain communities thrive near hydrothermal vents.

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Hermit crab habitat

Hermit crabs often use whelk shells as shelter, a substitute for natural rock crevices or under-boulder habitats.

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Whelk shell occupants

Various organisms utilize whelk shells, such as oysters, tubeworms, barnacles, sponges, worms, and anemones.

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Commensal relationship

One organism benefits from the presence of another without harming it, as seen in the worm feeding on crab scraps.

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Community adaptation

Communities adapt to minor environmental changes by adjusting the presence/absence of species, based on individual species' tolerances.

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Dynamic equilibrium

A natural balance in a community, where one species' growth is countered by rising competition or predation.

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Environmental parameters

Factors like temperature and weather events influence community structure and species interactions.

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Species recruitment

The process of new individuals joining a species' population.

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Species mortality

The rate at which individuals die in a species' population.

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Photosynthesis in Shallow Water

Shallow-water species utilize sunlight for energy production via photosynthesis.

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Deep-water Species' Energy Source

Deep-sea species obtain energy from consuming dead organic matter.

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Chemosynthesis

Producing energy from chemical reactions instead of sunlight, typically by bacteria.

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Chemosynthetic Bacteria

Bacteria that use chemical reactions to produce their own food.

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Abyssal Sediments

The sediments found in the deepest parts of the ocean.

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Marine Snow

Clumps of organic material sinking from surface waters to the deep sea.

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Zooplankton Exoskeletons

The hard outer shells of tiny animals in the surface ocean that contribute to marine snow.

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Marine Snow's Importance

Marine Snow is a vital transport system efficiently delivering organic matter to deep-sea organisms.

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Whale fall

The carcass of a whale that reaches the deep seabed, creating a localized food oasis for diverse scavengers.

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Scavengers

Animals that feed on dead organisms. In whale falls, they consume the carcass, spreading its nutrients.

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Osedax

A genus of bone-eating worms that consume the bones of whales, playing a vital role in the breakdown of these large structures.

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Time-lapse photography

A method used to study the decomposition of whale falls, capturing the changes over long periods in a compressed timeframe.

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Sediment traps

Devices used to collect marine snow, allowing scientists to study the seasonal variation in its deposition.

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Atmospheric CO2 transfer

Marine snow plays a key role in moving carbon dioxide from the atmosphere to the deep ocean, affecting climate change.

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Deep-water sediment trap

A type of sediment trap designed for use in deep ocean environments, typically employing a large funnel and a rotating collector.

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Joint Global Ocean Flux Study (JGOFS)

A major scientific research project conducted in the 1990s to study the flow of organic matter through the ocean.

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Kelp forest

A highly productive marine ecosystem dominated by large brown algae called kelp, providing a framework for a diverse community.

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Giant kelp

The largest type of kelp, growing to heights comparable to tropical rainforest trees.

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Biologically generated habitat

A habitat where the physical structure is created by living organisms, like a kelp forest.

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Laminariales

The order of brown algae that includes all types of kelp.

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Macroalgae

Large, multicellular algae, like kelp, visible to the naked eye.

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Worm's Food Source

These worms lack a mouth and gut, relying on symbiotic bacteria living within them to process nutrients from dissolved bone.

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Bone-Eating Worms

These creatures possess a root-like body that penetrates and dissolves bone using acid, releasing fats and proteins for their symbiotic bacteria.

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DOM Uptake

Deep-sea benthic animals can directly absorb dissolved organic matter (DOM) from the water, bypassing the need for bacteria.

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Giant Tubeworms & DOM

These organisms lack an internal digestive system and obtain energy from DOM along with energy from symbiotic chemosynthetic bacteria.

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Marine Invertebrates & DOM

Many marine invertebrates, besides ingesting solid food, absorb nutrients like amino acids and fatty acids directly from seawater.

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DOM Efficiency

Soft-bodied invertebrates with a large surface area are most efficient at absorbing DOM, like sponges and cnidarians.

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Interstitial DOM Source

Dissolved organic matter is abundant in sediment interstitial water, readily available to microorganisms and potentially benthic invertebrates.

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DOM and Energy

Dissolved organic carbon is estimated to contribute significantly to the energy requirements of deep-sea animals like starfish and polychaetes.

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Larval Settlement Cues

Signals used by settling larvae to identify suitable locations for metamorphosis, including light, touch, and chemical cues.

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Organic Substrata Attraction

Larvae, especially those settling on organic materials, often use chemical senses to detect and be attracted to their preferred substrate.

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Ophelia bicornis & Sediment Choice

This small polychaete worm has larvae that actively select specific types of sand for metamorphosis, showing preference for clean, loose sand and avoiding others.

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Sand 'Attractiveness' & Repellence

Larvae of Ophelia bicornis can distinguish between sands from different locations, exhibiting attraction to certain sands and avoidance of others.

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Biofilm's Role in Settlement

The coating of organic materials and bacteria (biofilm) on the surface of sand grains plays a significant role in attracting or repelling larvae.

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Upper circalittoral zone

The upper part of the circalittoral zone, characterized by low light levels and animal growth dominating over foliose algae.

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Obligate Associations & Cues

Animals that depend on another animal for survival utilize cues emanating from their host to locate and settle.

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Spirorbis spirorbis & Seaweed

The larvae of the spiral tube worm Spirorbis spirorbis use cues released by the seaweed Fucus serratus to find their preferred habitat.

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Lower circalittoral zone

The lower part of the circalittoral zone, where sunlight is very limited, and animal growths are the dominant life form. Calcareous encrusting algae may be present here as well.

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Benthic organisms and currents

The speed of the bottom current influences benthic organisms by affecting food availability, sediment composition, oxygenation, and the dispersal of larvae.

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Gastropod Preference

The gastropod Tritia obsoleta larvae are attracted to mud, demonstrating that different species have different preferences for settlement cues.

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Moderate wave action

Moderate wave action can be beneficial to benthic communities by providing food, oxygen, and dispersal of larvae, resulting in richer communities.

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Strong wave action

Strong waves can be extremely destructive to benthic communities, damaging animal growths and displacing organisms.

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Hydrostatic pressure and deep-sea communities

Hydrostatic pressure is a major factor shaping differences between communities found within ocean trenches and other deep-sea areas, especially when temperature and salinity are uniform.

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Filter-feeding

A feeding strategy common among benthic organisms in areas with strong currents, where they draw in water and filter out food particles.

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Adaptations for filtering

Benthic filter-feeders require special adaptations to separate food particles from large quantities of silt and sediment, ensuring efficient feeding.

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Marine Habitat Classification

A system used to categorize different types of marine habitats based on their characteristics.

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Petersen's Communities

Early classification system based on identifying the most prominent species within a benthic community, named after those species (e.g., Venus communities).

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Thorson's Communities

Classification system that focused on prevalent genera rather than species, acknowledging that the same genus could have different species across different regions.

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Wide Range Species

Some marine species are found over vast areas, leading to challenges in classification because they can exist in different communities.

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Classifying Benthic Communities

Benthic communities can be classified based on physical and chemical parameters like depth, substratum, temperature, and salinity. This method acknowledges that species distribution is tightly linked to these factors.

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Jones's Shelf Communities

Jones (1950) classified the northeast Atlantic shelf communities based on depth, substratum, temperature, and salinity, encompassing both sediment and rocky bottom communities.

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Glemarec's Contribution

Glemarec (1973) discussed the principles behind classifying benthic communities, drawing attention to the European North Atlantic benthos, influencing modern classification systems.

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Modern Classification System

The current benthic classification system draws upon early studies, extensive survey data, and computer technology. It integrates physical habitat and species approaches, resulting in well-defined biotopes.

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Limitations of Classifications

All classification systems have limitations because the seafloor is continuously changing, species have overlapping distributions, and boundaries between communities are often gradual.

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Climax Community

A stable community where species coexist in a natural balance, reflecting the specific local environment.

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Environmental Gradients

Changes in the environment create gradients, leading to overlapping distributions of species, shaping the overall community structure.

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Species Interactions

Species interactions, like competition and predation, influence the composition and stability of a community.

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Meiobenthos

Tiny marine animals, usually smaller than 0.5 mm, that live between sediment grains. They play a vital role in the food web, connecting bacteria to larger organisms.

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Microbenthos

Even smaller organisms than meiobenthos, including bacteria, flagellates, and ciliates, found in the same habitats. They are crucial in decomposing organic matter and nutrient cycling.

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What's a permanent deposit?

In the context of marine ecosystems, 'permanent deposit' refers to organic matter that sinks from the surface waters and accumulates on the seabed, providing a food source for benthic organisms.

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How do deep-sea communities get food?

Deep-sea communities rely primarily on the organic matter that sinks from the surface waters, called marine snow and other forms of permanent deposit, to obtain energy and nutrients.

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Interstices

The small spaces between sand grains where meiobenthos typically reside.

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Trophic Link

The connection between different organisms in a food web, showing who eats whom. Meiobenthos act as a vital link between bacteria and larger organisms.

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What types of food do benthic organisms eat?

Benthic organisms eat a variety of food, including dead organic matter (marine snow), bacteria, meiobenthos, algae, and sometimes even live animals depending on their diet and feeding strategy.

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Study Notes

Benthic Organisms

  • Benthic organisms live on or in the seabed, from the seashore to abyssal depths, covering a vast range of habitats.
  • Sublittoral communities are found on continental shelves, up to 200m deep.
  • Bathybenthic communities extend down the continental slope to about 4000 m.
  • Abyssobenthic communities are in the deepest parts of the ocean.

Substratum

  • The seabed substratum's type heavily influences benthic distributions.
  • Hard, rocky seabeds support epifauna (surface-dwelling) and epiflora.
  • Sediment-covered areas have infauna dwelling within the sediments.
  • Diverse habitats in rocky areas lead to more species diversity compared to sediment areas where conditions are usually more uniform, as local conditions are more consistent.

Physical Factors

  • Light penetration is limited at depth, decreasing to less than 1% at 200 meters.
  • Light is essentially absent below around 1000 m.
  • Wave action impacts seabed habitats, affecting depths up to about 150-300 meters depending on wavelength.
  • Water currents influence sediment particle size, nutrient content, and dispersal of pelagic larvae, transporting food particles and affecting oxygen content.
  • Temperature and salinity variations are less significant below 500m.

Benthic Communities

  • Different parts of the seafloor are inhabited by different communities, with distinctive organisms in specific geographic and environmental areas.
  • Differences result from water and substratum characteristics, including various sediment types, currents, and light penetration.

Physical Factors Affecting Benthic Communities

  • Temperature
  • Water composition
  • Water movement
  • Pressure
  • Light
  • These factors affect species distribution and community makeup, particularly in terms of stability and resilience.

Selective Settlement of Larvae

  • Larval settlement is not random, influenced by selection of habitats.
  • Biotic and abiotic factors influence larval choice, including roughness, slope, texture, chemical nature, and often color of the substratum.
  • Biofilms on surfaces, either attracting or deterring settling larvae, are an important factor.

Competition and Predation

  • Species compete for space and resources, leading to dominance relationships.
  • Predators impact community composition and abundance. This can lead to shifts in distribution and abundance of species.

Coral Reefs

  • Coral reefs are highly productive and biodiverse, creating complex food webs and shelter.
  • Dominated by one dominant species (kelp), forming a structural habitat framework.
  • Kelp forests have an understory of algae.
  • Kelp Forests are found in temperate, cold areas, with temperature and water clarity affecting growth.
  • Reefs have various zonation patterns, each with specific species associations, depending on depth, water exposure, and other factors.
  • Reefs vary in complexity, stability, and resilience depending on physical factors, such as wave action, currents, and temperature.

Hydrothermal Vents and Cold Seeps

  • These communities are not dependent on sunlight.
  • Chemosynthetic bacteria form the base of the food web.
  • Vent communities are often rich with large, unique animals.
  • High diversity of specialized species is found. These communities are located at unique geological features, such as mid-ocean ridges and in areas with significant hydrothermal activity.

Sampling and Collecting Benthos

  • Various methods are employed for sampling in different niches.
  • Trawls and dredges are large nets dragged along the seabed.
  • Corers also take sediment samples.
  • Specialized instruments, like ROVs and submersibles are used for sampling deep-sea communities.
  • Various methods are crucial for understanding benthic ecosystems, including accurate measurements of sample locations.

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Benthic Living: Sublittoral and Deep Seabed PDF

Description

Test your knowledge about deep-sea ecosystems and the unique adaptations of bottom-dwelling animals. This quiz covers various aspects including food sources, habitat diversity, and the roles of different marine species. Dive into the complexities of ocean biodiversity and the impact of human exploration techniques.

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