Lec 5- aquatic biomes Flashcards
biomes
- way of categorizing ecosystems
- distinguished by dominant plants and climates (terrestrial) or movement and physical properties of water (aquatic)
kinds of marine biomes (5)
ocean/salty
- open ocean
- deep ocean and thermal vents
- kelp forests and coral gardens
- intertidal
- salt marshes and mangroves
open ocean
pelagic
deep ocean
benthic
intertidal
littoral
kinds of aquatic biomes
freshwater
- lakes
- rives and streams
- wetlands
lakes
lentic
rivers and streams
lotic
aquatic sys in Canada (8)
ocean
- open ocean, kelp forests, intertidal zone, estuaries (salt marshes and mangroves)
- lakes
- ponds
- rivers
- streams
- wetlands
- bogs
- fens
Oceans
70% of world
zones:
- littoral (intertidal) zone
- neritic zone
- oceanic (pelagic) zone
- zonation of habitat: benthic and pelagic
littoral zone
shallow shoreline, under influence of tides
neritic zone
coast to margin of continental shelf
oceanic zone
beyond continental shelf
- epipelagic 0-200
- mesopelagic 200-1000
- bathypelagic 1000-4000
- abyssal 4000-6000
- hadal 6000+
benthic
habitat at bottom of ocean
pelagic
habitat off the bottom, in open water
open ocean
pelagic
physical: light and temp dependent on depth, gyres, light decreases w depth
chemical: salty, o2 concentration correlated with depth
biological: photic zone, low densities
deep ocean and thermal vents
physical/chemical: chemosynthesis-based ecosystems, no light
biological: highly adapted organisms, little known, hard to study b/c adapted to high pressure
kelp forests and coral reefs
higher latitudes, ocean currents
biomes analogous to terrestrial forest
between Tropics
kelp across rocky shores and eat coast
kelp: 30 degrees latitude or high cooler temp
coral reef/garden: 30 degrees latitude or lower warm temp
- highly vulnerable
- high productive organisms
Ekman spiral
starts at surface then moves down in specific movements
- Coriolis effect and wind move large water masses in vertical fashion
- with increasing depth, forces diminishes and changes direction due to friction in water
- wind directed water movement resembles vertical spiral
- net transport direction will be 90 degrees than surface wind direction
- key to transport of energy
Coastal upwelling
- wind driven off-shore movement of water
- deeper waters replace displaced water nearshore
- deeper waters nutrient-enriched
- kelp forest
intertidal
littoral
- ocean meets land
- rise and fall of tides
physical/chemical: tides, high light, temp closer to air temp, oxygenated
biological: amphibious. part marine and part terrestrial, starfish, mussels, algae
salt marshes and mangroves
- saltwater and freshwater mix
- river into ocean
physical/chemical: highly variable and dynamic like intertidal, salinity fluxes
biological: marshes = grass, mangroves = trees, low diversity but high productivity
lotic ecosystems
rivers and streams- natural channels of moving water, differ in sizes
rivers, streams, creeks/brooks
canals are human-made channels of flowing water integrated into an ecosystem
size depends on substrate, energy, photosynthesis
smaller have higher turbidity and less photosynthetic organisms
rivers
physical/chemical: water moves, turbid, lots of suspended sediment, temp similar to air
biological: fish-variety, macroinvertebrates-benthic invertebrates
lentic ecosystems
lakes = relatively deep large bodies
> 3m depth and >1 ha surface area
ponds = smaller, often fishless
wetlands = shallow, dominated by water-logged soils and aquatic vegetation
lakes
lentic
- physical/chemical: more dynamic, “mini-oceans”
- biological: organisms vary by layer, light level, planktonic: free floating, nektonic = free swimming
wetlands, bogs and fens
physical/chemical: decomp rate lower than production, still water, low O2
biology: structurally slowly decomposing organic material
Peatlands
bogs and fens
- wetlands come in form of either forming peat or not
peat: partially decomposed plant material that builds up in certain poorly drained wetlands
bogs: in depressions in landscape
fens: receive water from ground or surface
what are the key drivers of freshwater and marine ecosystems?
solar radiance
nutrients
how are freshwater ecosystems contrasted?
based on flowing vs standing water
what drives freshwater ecosystems?
landscape factors
what regulates marine ecosystems?
oceanic currents
what is a niche?
set of environmental conditions in which an organism can survive and reproduce
- abstract, not physical conditions
fundamental niche
physical conditions which species night live in ABSENCE of interaction with other species
- no competition
realized niche
environmental conditions which species might live when restricted by interactions with other species
- smaller than fundamental
ecological niche- people (3)
Grinnell (1917, 1924)- abiotic factors
Elton (1927) - abiotic but more on biotic interactions
Hutchinson (1957)- realized niche, an n-dimensional hypervolume
- n = # of environmental factors important to survival and repro, generalize it
- humidity vs them to get pH
MacArthur’s warblers
fundamental
5 species in spruce in NA
observed using binoculars and stopwatch
realized
- coexist in same tree by restricting feeding to certain areas- niche partitioning
Competitive exclusion principle
no 2 species will occupy same realized niche, eventually one will out-compete the other
Niche partitioning
when species in community use limiting factors in diff ways they will occupy different realized niches
