Marine Ecology Flashcards
1
Q
ecology
A
interaction of organisms with the environmnet
2
Q
what are important factors determining oceanography at the surface
A
light, temp, OM (others: crustal geomorphology, marine comm patterns, comm composition)
3
Q
continental shelves
A
richly populated, inconsistent conditions
4
Q
deep oceans
A
dark + cold, sparse, consistent conditions
5
Q
littoral zone
A
high diversity in interactions
6
Q
issues with finding marine ecology
A
-marien life unknown, sampling costly, logistical challenges (eg. depth)
7
Q
remote ways to test marine ecology
A
tagging, satellites
8
Q
why are oceans diverse
A
gradients + less isolation increases connectivity decreasing rich availability and specation
9
Q
what factors form gradients
A
latitude, depth, coastal to pelagic (nutrient availability)
10
Q
crustal geomorphology
A
important in distributing nutrients + water (eg. Mid Atlantic ridge)
11
Q
general driving factors for comm composition
A
comp, disturbance, pred, environmnetal pertubation
12
Q
why is understanding factors driving comm composition important
A
water used to reproduce, orgs evolve to feed on plankton, space is soft-bottomed + easily disturbed, less resource + space comp in oceans
13
Q
function of MEOW maps
A
define ecoreions in world, conservation planning, wider issues: assess biodiversity + evolution
14
Q
what is sediment type determined by
A
seafloor type, OM %
15
Q
what is OM production driven by
A
photosynthesis, light
16
Q
what is light driven by
A
penetrating wavelengths, light amount (angle of incidence)
17
Q
what are light response curves
A
showing light over photosynthetic rate, compensation point (where PP and basal MR is 0), changing light intensity changes PP amount
18
Q
Depth response to NPP response
A
depth correlated with/ light intensity,
19
Q
compensation depth
A
when light intensity is too low for photosynthesis>respiration (orgs can’t survive)
20
Q
factors controlling PP
A
turbidity, transport systems, CO2, light, OM
21
Q
factors increasing turbidity
A
wind, semidiurnal + spring neap tides
22
Q
why is fetch important for transport systems
A
regulates balance of SS + phytoplankton, creates spatial variability
23
Q
Effect of greater fetch
A
more planktonic growth (in neap) + decay (in spring), stronger distribution gradients
24
Q
effects of CO2 in the ocean
A
increase acidity + ocean acidification (impacts coccolithophores =calcification)
25
how is PP measured for corals
use model sp. (anemones)
26
key nutrients
nitrogen, ammonia, phosphorus, iron
27
GPP
gross PP
28
NPP
net PP
29
why is understanding balance between respiration + photosynthesis important
for understanding energy budgets across scales + finds biomass
30
respirometry
measure MR from O2 flux changes
31
explain photosynthetic algae in corals
symbiosis convert inC from atmosphere into OM, fluorescent proteins absorb light
32
why do we measure sea anemones
lots of diff habitats + morphologies, keystone sp., some have diff morphs (eg. green + brown, have diff photosynthetic efficiency)
33
what are nutrients found as in oceans
detritus, constitutens
34
types of detritus in ocean
POM, marine snow
35
what is POM
bacteria, diatom skeletons
36
what is marine snow
faecal matter, gelatinous photosynthesis sheaths, larvacean houses, bio exudates of phytoplankton
37
function if marine snow
sites of photosynthesis, respiration, nutrient regeneration
38
what is marine snow distribution governed by
OM production, water movement (currents, eddies, upwellings)
39
stoichiometry
ratio of C:N:P = 10:1-7:1 (marine snow doesn't follow Redfield ratio)
40
why are higher C:N ratios of marine snow are nearer surface
C recycled in upper ocean via transport systems (biological C pumps)
41
scavenging
absorption of metal complexes onto particulate surfaces
42
how is marine snow formed
facilitated by bac on surface, attach onto marine snow via ionic attraction, elements captured + fall down
43
carbon pump
combo of biological, physical, chemical processes controlling C transfer (dominates C sequestration)
44
process of C pumps
turns CO2 into organic C + O2, sinks + resaturates (N+P limits metabolism)
45
why is whale carbon pump important
large size, extensive distribution, functional processes, minimises value for C capture
46
how do whale c pumps transfer C
feeding on krill at surface, diving (deep dives, return and expel faeces), dying (nutrients + iron reach floor)
47
why is the C whale pump important
seabed nutrient poor (few processes for nutrient transfer), stimulates horizontal + vertical C fixation, important C sink
48
issues of whale C pump
industrial whaling removed 81% (change top-down car), important biomass stores (reduction- lower C biomass)
49
how do we get organic nitrogen
N biologically produces (not available for atmosphere), denitrification bacteria convert N intro bio-available, balance of notification + denitrification always fluctuates
50
distribution of N
low are surface in upper ocean, iron is low sub-suface by N is abundant (as not as used + deep-sea currents)
51
nitrification
fixed by autotrophic bad Nitrosomonas sp + cyanobacteria: trichodesmium
52
denitifcations
facilitated by heterotrophic back (N gas + CO2 produce ammonia + nitrate)
53
importance of N
limits productivity in low lats (so limiting factor), controls abundance of marine sp driving processes
54
ways terrestrial convert N
seabirds transport N from oceans to isolated islands, N leaches from rainfall + coastal asdvection
55
importance of iron
limits productivy
56
distribution of Phosophorus
passive distribution, only available when heavily recylced, high in coal, low in n.atlantc, high in upwelling arreas
57
why is nitrogen + phosphorus strongly correlated
due to P availability
58
importance of silicate
diatom construction, important particularly in S.ocean
59
distribution of silicate
matches N, mainly at 60 lat
60
silicate cycle
bloom over thermocline, thermocline falls, rapid deposition of frustules, silicate + OM pushed to seafloor
61
why do warmer seas have less nutrients
downwellings in polar push more currents, high nutrients found in polar regions
62
causes of plankton blooms
river inflow, vertical + horizontal stratification, turbulent mixing, benthic + pelagic grazing, nutrient + light availability (also: predation deterrence traits, light acclimation, adaptation, nutrient affinity + growth rates)
63
structure types of marine habitats
no structure (pelagic), 2D (sediment-based), 3D (trophic + environmental factors eg. reef)
64
what biotic factors affect comm structure
facilitation, dispersal, recruitment, interferene/comp, predation
65
what abiotic factors affect com structures
light
66
facilitaion
interaction between >2 sp that benefits one and harmful to none
67
why is facilitation important
for stressful environments (tidal cycles to desiccation + stress gradient)
68
stress gradient hypothesis
facilitation important in stressful environments
69
example of facilitation
seaweed reduce thermal + dessication
70
foundational sp.
oyster reef, coral reefs, kelp, seagrass
71
function of foundational sp. as facilitators
reduce abiotic stress, provide substrate for growth, increases food supply
72
kernel
unit of larval dispersal
73
what is dispersal of kernels determined by
survival rate, water movement
74
why is distribution important
comms connected over large distances, create isolated comms
75
what is recruitment rates controlled by
diff preferences for sediment types + them + environmental cues for settlement
76
process of settlement
teach for suitable substrate, permanent residence/attachment, metamorphosis from larval
77
cues for recruitment
sp. existence on same type of(light lvls, body orientation), physical environmnet lvls
78
why is seasonality lvls important in recruitment
ocean in current cycles + mixing lvls, in artic experience sig disturbance
79
key biotic mechs for competition
inter-specific comp, predation, adult interactions
80
why predation has little effect on comm structure
larvae removed grazers, limits carrying capacity (some basins more driven than others)
81
importance of interactions on each substrate type
soft: not much )density below carrying capacity) rocky: important
82
what do you need to understand to understand comm patterns
abundance, sizes, weight, sp. richness
83
where is hotspots of niodiversity
coral triangle, eqautaro, coastal
84
why doesn't hotspots of marine biodiversity not always match PP
LDG
85
how do marine habitats differ to terrestrial
continuous, productive seas small proportionally
86
LDG
declinigin sp. richness moving away from equator, more ewimprotant regionally, stronger than freshwater
87
issues of LDG
not fully accurate, regional hotspots skewing data
88
3 key benthic sp.
epifauna, infauna, mobile sp.
89
epifauna
form complex comms, add 3D structure, high in intertidal poor in polar
90
infauna
highly successful (<50%), numerate, cover seafloor, eat plankton + detritus + bac
91
meiofauna
live in gaps of sediment grains, rely on O2
92
macrofauna
more diverse, move in sediment (bioturbated + nutrient cycling), filter feeders
93
megafauna
large influence areas, lots of space resources
94
why is sediment type improtant
determines structure + benthic function, detmerine comm assemblages
95
factors of soft sediments
flat, lacks veg, animals only associated with other fauna
96
how is sediment formed
glacial cycles, deposition of riverine mat, OM sinks down water column, sediment weaving
97
basic food web conepts
food webs show feeding relationships among sp. within community, feeding groups are trophic lvls, indirect + direct interactions, described bottom-up + top-down ctrl
98
importance of trophic interaction
control biomass fluxes
99
interactions between benthic + pelagic
birds, macrophyte innitrient uptake, suspension feeding, resuspension, allochthonous organic input, fish press, diffusion of larvae, bioti=urbation, sedimentation
100
importance of microbial loop
understand trophic systems
101
functional response theory
more food=more consumption, consumption rates not equal
102
parameters of functional reposnse
space clearance rates, handling time, density dependant space clearance rate
103
what drives functional responses
succès rate, digestion times, handling time
104
functional response theory
that animal will feed when prey available iw rarely me (due to beaHVIOURAL DIFFS) - handling is to do with/ physiology + capture about encounters in space
105
why are seagrass important
globally distributed, highly productive, high phenolic to structural C ratio (structural defence), rapid growths, supports abundant comms,
106
how seagrass enters food chain
directly consumed by herbivores (<50%), OM forms detritus
107
habita structure os seagrass is unique as
high SA, macroalgal growth
108
pros of epiphytic growth on seagrass
grazing increases stimulating rot growth, production + areal productiivty
109
cons of epiphytic growth on seagrasses
inhibit grazing
110
mutualistic grazer model
how segarass + epiphytes change distributions influencing physiology
111
