Aquatic Biomes, Ocean Zones, and Marine Conservation Strategies

Freshwater biomes

Streams, rivers, ponds, and lakes; major sources of drinking water.

Marine biomes

Intertidal zones, coral reefs, open ocean, marshes, swamps, and estuaries.

Coral reefs and estuaries

Highest productivity and biodiversity; especially productive and species-rich.

Marine algae/phytoplankton

Supply large amounts of oxygen and absorb carbon.

Wetland categories

Marshes are non-woody, swamps are woody, and bogs are acidic with peat/sphagnum moss.

Coastal nutrients

Near-coast waters are often higher due to runoff flowing to rivers and estuaries.

Key Abiotic Conditions

Depth, light, temperature, velocity (currents), salinity, oxygen, nitrates, and phosphates.

Intertidal zone stressors

Daily shifts in sunlight, temperature, and water exposure require tolerance to desiccation and wave impact.

Littoral zone

Shallow nearshore zone; most photosynthesis occurs here.

Limnetic zone

Open water as deep as sunlight penetrates; phytoplankton only.

Profundal zone

Deep water; no sunlight; bacteria decompose; low oxygen.

Benthic zone

Muddy bottom of lake/pond/ocean beneath limnetic and profundal zones.

Oligotrophic

Low phytoplankton; very clear water.

Eutrophic

High fertility; dense algae; turbid water.

Mesotrophic

Moderate fertility.

Estuaries and salt marshes

Nutrient-rich nursery/spawning habitat for about 75% of marine fish.

Mangrove swamps

Salt-tolerant coastal forests that reduce storm damage and erosion.

Coral reefs

Extremely diverse; coral-algae mutualism with zooxanthellae.

Open ocean photic zone

Light penetrates to about 200 meters; phytoplankton form food-web base.

Aphotic zone

No photosynthesis; chemosynthetic bacteria using methane or sulfur can support deep-sea food webs.

Wetlands definition

Areas where soil is covered by or near water for all/most of the year.

Oligotrophic condition

Very low nutrients, stable algae, and high dissolved oxygen.

Flood control function

Wetlands store water and release it slowly, reducing flooding.

Mangrove carbon uptake

Mangroves can absorb about 4 times more carbon than trees in some comparisons.

Development threats

Habitat destruction, altered flow, and increased sedimentation from commercial building.

Fishing techniques

Methods include dredging, long-lining, purse seine, and drift nets.

Bycatch concept

Unintended catch that can kill non-target species.

Fishery collapse definition

Population decline of about 90% or more.

Consumer leverage

Seafood guides categorize choices to reduce pressure on vulnerable stocks.

Aquaculture definition

Farming fish/shellfish/mollusks/crustaceans/aquatic plants for sale.

Production advantages of Aquaculture

Reliable protein and income; typically uses less land, water, and fossil fuels than terrestrial agriculture.

Pollution disadvantages of Aquaculture

Nitrogenous waste and uneaten feed can drive eutrophication and degrade water quality.

Escape and disease risks in Aquaculture

Escaped organisms can compete or interbreed with wild populations; pathogens/parasites can spread.

Medication impacts in Aquaculture

Antibiotics/chemicals can contaminate waterways.

Eutrophication process

Excess nutrients drive algal/plant blooms; commonly linked to runoff and detergents.

Aquaculture scope

Cultivation of aquatic organisms for food; described as rapidly increasing.

Common farmed species

Salmon, shrimp, and oysters.

Advantages of Aquaculture

Reduces fishing pressure on wild stock; increases jobs.

Disadvantages of Aquaculture

Disease in close-proximity conditions; high setup cost.

Growth significance of Aquaculture

Aquaculture is described as the fastest-growing food production method.

Aquaculture system types

Open-net pens, submerged-net pens, pond farms, and recirculating above-ground tanks.

Food-security benefit of Aquaculture

Can increase protein availability and reduce pressure on wild fisheries.

Wastewater pathway in Aquaculture

Feces, uneaten food, and antibiotics can be released back to waterways.

Pathogen spillover from Aquaculture

Sea lice and diseases can spread from farms to wild fish.

Escape impacts of Aquaculture

Farmed fish can compete with, interbreed with, and transmit disease to wild populations.

Containment innovation in Aquaculture

Above-ground recirculating systems can reuse waste as plant fertilizer; algae can be cycled back as feed.

Range of tolerance concept

Species survive, grow, and reproduce within an optimal abiotic range; outside it causes stress, reproductive failure, or death.

Thermal stress on coral

Increasing ocean temperatures can push coral outside its tolerance range.

Sediment runoff effect

Turbidity reduces light penetration and harms photosynthetic partners/primary production.

Hydrocarbon toxicity

Oil exposure can kill marine organisms and devastate detritivore communities.

Coating mechanism of oil spills

Oil reduces insulation/waterproofing in feathers and fur, raising mortality risk.

Economic consequences of oil spills

Spills can reduce tourism and harm fishing industry income.

Dead zone mechanism

Fertilizer runoff increases algal blooms; decomposition depletes dissolved oxygen, collapsing local fisheries.

Oxygen sag curve use

Dissolved oxygen is lowest in the decomposition/septic zone downstream of a pollution source.

Mercury bioaccumulation

Elemental mercury can be transformed to methylmercury by bacteria and biomagnify up food chains, harming wildlife and humans.

Plastic/litter hazards

Ingestion and entanglement cause choking/blockage and can introduce toxins into food webs.

Sediment pollution

Turbidity lowers light, harms primary producers and visual predators, and disrupts habitat structure.

Mid-ocean ridge formation

Divergent boundaries create underwater mountain chains via seafloor spreading.

Mountain building

Continental-continental convergence forms large mountain ranges.

Island arc creation

Subduction-related volcanism forms curved island chains.

Trench formation

Subduction bends the denser plate downward, creating deep seafloor trenches.

Core

Innermost; iron/nickel; liquid outer plus solid inner.

Mantle

Above core; contains magma and asthenosphere (semi-molten).

Lithosphere

Solid upper mantle plus crust; about 100 km thick.

Crust

Chemically distinct outermost layer.

Troposphere

Crust and soil provide most chemical elements for life.

Plate tectonics frame

Lithosphere is divided into plates in constant motion.

Richter scale property

Logarithmic; each unit corresponds to a tenfold increase in earthquake magnitude.

Hot spot concept

Mantle plumes can create volcanic island chains (e.g., Hawaii) as plates move.

Seafloor spreading

New crust forms at mid-ocean ridges and moves outward.

Subduction

One tectonic plate sinks below another; oceanic plates subduct beneath continental plates.

Continental drift evidence

Matching rocks and fossils across the Atlantic supported Wegener's Pangaea hypothesis.

Ring of Fire pattern

Many Pacific-margin volcanoes and earthquakes align with plate boundaries.

Volcano distribution

Most volcanoes occur along boundaries, with additional hot spot volcanism.

Earthquake impacts

Moderate to large earthquakes can collapse structures, contaminate water, and cause fatalities.

Tsunami triggers

Undersea earthquakes or volcanoes can generate tsunamis that amplify near shore.

Volcanic ash hazard

Fine particles can disrupt aviation and damage engines (example discussed: Iceland 2010).

Asthenosphere

Soft, flexible upper mantle layer that allows plate motion.

Convection current

Circular motion in heated fluids where warm rises and cool sinks.

Angle of incidence

Angle between incoming sunlight and a line perpendicular to the surface.

Coriolis effect

Earth's rotation deflects winds and currents, helping predict global patterns.

Albedo contrast

Dark forests have low albedo while snow/ice have very high albedo; Earth's average is about 0.3.

Equinox

Around March 20/21 and September 22/23, all regions receive about 12 hours of daylight.

Gyre

Large rotating surface-current loops driven by prevailing winds and the Coriolis effect.

Gulf Stream role

Warm current that moderates climates along eastern North America and western Europe.

Thermohaline circulation

Deep-ocean circulation driven by temperature and salinity; global cycle can take centuries.

Adiabatic rain shadow mechanism

Windward uplift cools and rains; leeward descent warms and dries.

El Niño

Winds stall/reverse to westerlies; warmer/wetter winter in Canada and N. U.S.

La Niña

Same as normal but more intense; cooler/drier S. America; colder winter in Canada and N. U.S.

ENSO Cycle

Occurs about every 2-7 years and can last from weeks to years.

Greenhouse effect

Greenhouse gases trap outgoing heat and warm Earth's surface.

Global warming

Increased greenhouse gases raise average surface temperatures.

Mitigation

Actions that decrease greenhouse gas concentrations or emissions.

Carbon footprint

Total direct and indirect greenhouse gas emissions from a person or organization.

Ozone

In the upper atmosphere protects from UV; near the ground it is a pollutant.

Renewable resource

Replenished as fast as used (unlike fossil fuels).

Resistance

Degree to which a disruption alters energy/matter flows.

Resilience

Speed of return to original ecosystem state after disruption.

Intermediate disturbance hypothesis

Intermediate disturbance can maximize diversity; too rare favors dominance, too frequent favors fast reproducers.

Fragmentation

One continuous habitat is split into separate patches.