BIOL 311 PARTII Flashcards Preview

2016/2017 > BIOL 311 PARTII > Flashcards

Flashcards in BIOL 311 PARTII Deck (294)
Loading flashcards...
1
Q

wavelength to measure silicic acid

A

410nm by visible spectrophotometry

2
Q

silicic acid

A

Si(OH)4

3
Q

most common way to determine amount of phytoplankton in seawater

A

Chlorophyll (mostly Chl a)

4
Q

[Chl]

A

index of phytoplankton biomass

intensity of fluorescence is proportional to amount of Chl and thus biomass

5
Q

most common way to measure Chl

A

use acetone to extract Chl from filtered sample, measure fluorescent using fluoromoeter

6
Q

fluorescence

A

photosynthetic pigments absorb light at one wavelength and emit light at another

7
Q

breakdown products of chl produced by zooplankton digestion

A

phaeopigments

8
Q

nitrate

A

NO3 -

9
Q

Secondary production

A

amount of new zooplankton tissue elaborated per unit time

10
Q

zooplankton are

A

secondary producers

key link between PP and higher trophic levels

11
Q

key zooplankton species

A

copepods

12
Q

PP regulated by

A

availability of light and nutrients

13
Q

principle photosynthetic pigment in all phytoplankton

A

Chlorophyll (mostly Chl a)

14
Q

Secondary production regulated by

A

food availability
temperature
predation

15
Q

food chain in upwelling systems

A

pretty simple chain

phyto.–zoo–higher trophic levels

16
Q

NO2-

A

nitrite

17
Q

food chain in open ocean

A

more complex web

‘secondary production’ somewhat ambiguous

18
Q

estimating SP

A

TTE

Measuring (3 methods)

19
Q

TTE

A

Trophic Transfer Efficiency
TTE (Et) = Pt / Pt-1
TTE = amount of E; annual production at t / annual E in lower trophic level

20
Q

TTE assumptions

A

TTE of 10% is always a good estimate

We can account for biomass of all un-fished species in food web

21
Q

IS TTE reliable

A

TTE often 15-20% at lower levels, using 10% not always adequate, would lead to underestimates, better to measure SP directly

22
Q

Why is it easy to measure PP

A

can measure various ways: O2 production, CO2 uptake, nutrient uptake, colour w/ satellites
Rapid generation time: can estimate PP w/i few hours

23
Q

why is it not easy to measure SP

A

Much slower growth (weeks-months)

Have to focus on one species at a time

24
Q

Methods for measuring SP

A

physiologic method
cohort analysis
chitobiase method

25
Q

The physiologic method

A

only certain amount of phyto. E is transferred to zoop.; calculate all inputs and outputs; requires a lot of information

26
Q

Inputs/outputs in SP

A

Input: phytoplankton
Outputs: respiration, excretion, defecation, death, melting, consumption by predators

27
Q

Cohort analysis

A

follow zoopl. cohort through t; must know length of life stage and weight, very difficult at sea

28
Q

Copepod life cycle

A

12 stages: adult, nauplii (6?), C1-C5 copepodites
seasonal vertical migration
rise to surface as nauplii early spring

29
Q

SP cohort analysis, abundance vs time

A

Abundance (m^-2) vs Time (days)

abundance increase and decrease for each life stage, curves progress with time for successive life stages

30
Q

Cohort analysis, 2ºP =

A

Σ G_i B_i

weight-specific growth rate of stage i * biomass of stage i

31
Q

Biomass =

A
B = X* w
X = # individuals
w = weight of individual
32
Q

Production =

A
P_t = [(X1-X2) * (w1+w2)/2] + (B2-B1)
x = # individuals
w = average weight
B = biomass
33
Q

Cohort analysis assumptions

A

populations are synchronous
sampling animals each day
not very accurate, makes difficult to use correctly

34
Q

Landry, 1978

A

one of few proper cohort analyses
found production rate for single copepod species, single season, in a single lagoon
not comparable to high resolution of PP studies

35
Q

synchronous populations

A

developing through life stages at the same time

36
Q

Mesocosm

A

encircle large V of water + plankton
typically 2-5m wide, 3-10m deep
popularized in oceanography by Tim Parsons

37
Q

Artificial cohort method

A

popular field method

incubate specific stages/size classes for short periods

38
Q

problems with artificial cohort method

A

repeated handling (damaging)
container effects (food, T)
assumes asynchrony
time consuming, laborious (have to sieve samples and separate stages)

39
Q

Chitobiase method

A

Biochemical method for rapid estimation
measure chitobiase in water sample
fast and relatively simple

40
Q

what is chitobiase

A

crustacean moulting enzyme that recycles chitin during moulting of an individual
amount of chitobiase is proportional to body size

41
Q

Chitobiase method assumptions

A

decay rate proportional to production

42
Q

what does chitobioase method tell

A

estimate of average development rate of crustacean zooplankton community

43
Q

what is needed for chitobiase method

A

rate of decay of chitobiase from seawater sample

44
Q

Chitobiase method benefits

A

Fast, relatively simple, versatile, high resolution over short time

45
Q

Zooplankton food

A

phytoplankton
protozoans
other zooplankton

46
Q

zooplankton food use

A

growth
reproduction
routine metabolism and respiration

47
Q

how much food do zooplankton need

A

smaller zoop have higher weight-specific food requirements

smaller, higher T = higher metabolic rates

48
Q

food required (zooplankton)

A

inversely proportional to size

49
Q

How much phytoplankton do zoop consume

A

ca. 10-40%

occasionally nearly 100% of daily PP

50
Q

Zoop. food limitations

A

in lab higher nutrition levels required than are found in ocean, at low [food] there were lower body weights
Zoop in ocean not starving, reproduction not limited, food availability doesn’t seem limiting

51
Q

Field measurement of zoop reproductive output

A

usually show little-no relationship w/ food concentration

52
Q

What does Zoop growth rate depend on

A

*Temperature
body size/metabolism
resources

53
Q

max zoop growth

A

only occurs above threshold food concentration

highest for youngest stages

54
Q

zoop growth open ocean vs coastal

A

food-limited growth at [food] found in oceanic areas regardless of T

55
Q

habitat T vs food concentration

A

Cm, Cc increase w/ decreasing T
oceanic organisms fall mostly below Cc, some above at very low T
Coastal zoop almost entirely above Cc

56
Q

Cm

A

matintenance food concentration
assimilation balances respiration
below equals starvation (not enough food to meet metabolic needs)

57
Q

Cc

A

critical concentration

above which growth rate is max

58
Q

Habitat T vs Food concentration, Juvenile, Adult

A

Cm, Cc increase more at low T for adults, i.e. adults have more challenges reaching max growth at low T

59
Q

Food limitation conclusions

A

food limited growth most likely in oceanic conditions and large zoop

60
Q

why do only lab studies find food availability matters for zoop growth

A

either erroneous results or underestimate real food availability

61
Q

Huntley-Lopez Model (1992)

A

re-analyze published data, find T alone explains >90% of growth rate variation
suggest that SP can be estimated as fn of T

62
Q

Huntley-Lopez model, SP =

A

B * 0.445 *e^0.111T
T = temperature
B = biomass
SP in g C m^-3 day^-1

63
Q

criticism of Huntley-Lopez model

A

relies mostly on lab data collected under unrealistic condition
doesn’t align with what is seen in field

64
Q

food quality and zoop

A

bioindicators (e.g. fatty acids) have been shown to affect reproductive success and growth rate

65
Q

Annual changes in temperate oceans

A
angle of sun
insolation
stratification
nutrients 
compensation depth
66
Q

summer in temperature oceans

A

sun shines straight -highest concentration of energy- high heating of water- stratification- high PP - nutrient decline- deep compensation depth

67
Q

PP, SP patterns in temperature oceans

A

PP, SP high (peak) in spring, decrease in summer due to low nutrients, secondary bloom in fall due to upwelling (wind mixing, tides, etc), may be mini blooms throughout

68
Q

why does PP decrease after bloom

A

decreased nutrients

increase in SP - grazing

69
Q

overall temperature ocean productive pattern

A

strong seasonality

large export flux

70
Q

polar ocean productivity patterns

A

only 1 bloom, in summer, phyto/zoo/ nutr curves all pretty tightly coupled, strong seasonality

71
Q

tropical ocean productivity patterns

A

strong, permanent thermocline, barrier to mixing, low nut, low productivity year round, no blooms, very low increases/decreases (small blooms from small scale mixing), no seasonality, very little export flux

72
Q

tropical ocean productivity relies on

A

remineralization - regenerated system

73
Q

regenerated nutrients

A

ammonium, urea

74
Q

exceptions to low productivity tropics

A

coral reefs

equatorial and coastal upwelling zones

75
Q

temperate ocean productivity limitations

A

winter - light

spring/summer - nutrients

76
Q

polar region limits to productivity

A

summer - nutrients

all other times - light

77
Q

tropical region limit to productivity

A

all seasons - nutrients

78
Q

main grazers of ‘large’ phytoplankton cells

A

copepods

79
Q

why are phytoplankton blooms possible if they are grazed

A

zoo grow slower

80
Q

average productivity of upwelling zone

A

500 gC/m2/yr

81
Q

what areas of the ocean are most productive?

A

depends - per m2 = coastal, but coastal zones are small… overall = open ocean (pay attention to units)

82
Q

front

A

relatively narrow region characterized by large horizontal gradient in variables (e.g. T, S, D); sharp changes

83
Q

example of a frontal system in the ocean

A

edge of the continental shelf – increased productivity parallel to shore
between islands - different depths, flow lines changed

84
Q

Island effects

A

vertices formed downstream of a current moving past an island, disrupt nutrient patterns

85
Q

tidal effects

A

moving through narrow pass (e.g. estuary) causes eddies to form - disrupt water/nutreint patterns

86
Q

average productivity of open ocean

A

125 gC/m2/yr

87
Q

Large-Scab patchiness caused by

A

coast, river-plumes, fronts, island effects, divergence/convergence, gyres

88
Q

In NH net water movement is

A

to the right

89
Q

Continental divergence

A

water moving away from shore, deep water rises to replace = upwelling; always on W side of continent because waters are moving away (NH and SH)

90
Q

Planetary fronts

A

span entire ocean basins

91
Q

average productivity of continental shelf

A

360gC/m2/yr

92
Q

example of planetary front

A

Antarctica circumpolar current

Between subtropic and subpolar gyres

93
Q

anticyclonic gyre

A

clockwise circulation in NH (counter clockwise in SH)
water moves ‘in’ (to the right)
downwelling
warm water

94
Q

average productivity of coral reef

A

2000gC/m2/yr

95
Q

continental divergence =

A

high productivity

96
Q

continental convergence

A

waters ‘pile up’, downwelling, poor productivity, generally E side of continents

97
Q

gyre right hand rule

A

clockwise gyre - wrap fingers clockwise - thumb points away - water moves down

98
Q

effects of anticyclonic gyre

A

downwelling - warm water– low productivity

99
Q

warm core ring

A

anticyclonic gyre

100
Q

where reefs are generally found

A

continental convergent areas

101
Q

cyclonic gyre

A

anticlockwise circulation in NH (clockwise in SH)
water moves up/out (to the right)
upwelling, divergent, cold (NH and SH)

102
Q

cold core ring

A

cyclonic gyre

103
Q

Small-scale patchiness

A

Langmuir circulation

Deep scattering layer

104
Q

Langmuir circulation

A

‘streaks’ formed between langmuir cells; from moderate, persistent wind producing convection cells in topmost layer of water w/ long axes

105
Q

Deep scattering layer

A

result of diel vertical migration

106
Q

CO2 over the last 20,000 yrs

A

slow, steady increase up to 1800s then major increase

107
Q

effects of cyclonic gyre

A

upwelling - cold water - high productivity

108
Q

CO2 in 1750

A

277ppm

109
Q

CO2 in 2016

A

405ppm

46% increase since 1750

110
Q

first daily measurements of CO2 over 400

A

May 2013

111
Q

where are CO2 measurements made

A

Mauna Loa

112
Q

Fossil emissions graph

A

CO2 emissions per year = steady incline from 1990-now

113
Q

current CO2 emissions

A

9.9Gt C/yr

114
Q

contributors to CO2 emissions

A

Highest to lowest: Coal, oil, gas, cement

all have increased

115
Q

year-to-date globally averaged land surface T

A

1.48ºC above 20th century average

116
Q

year-to-date globally averaged sea surface T

A

0.77ºC above 20th century average

117
Q

RCP

A

Representative concentration pathways

118
Q

IPCC 5th assessment RCPs

A

RCP8.5 =3.2-5.4ºC
RCP6 = 2-3.7ºC
RCP4.5 = 1.7-3.2ºC
RCP2.6 = 0.9-2.3ºC

119
Q

Ice cores can tell how far back

A

800,000yrs

120
Q

RCP path we are on

A

likely not possible to meet RCP2.6 or RCP4.5 would have to remove CO2

121
Q

Dominant physical changed expected in the oceans as a result of climate change

A

surface layer warming
surface layer freshening
shallowing of upper mixed layer
increased stratification at base of mixed layer
changes in wind patterns and storm tracks

122
Q

physical changes to the ocean from climate change greatest

A

at high latitudes

123
Q

results of increased ocean stratification

A

less ‘diffusion’ of O2 down = anoxia

less mixing of nutrients up = lower productivity

124
Q

freshening is the result of

A

increased precipitation and glacial melt

125
Q

organisms in a changing climate, MAAD

A

Move
Acclimate
Adapt
Die

126
Q

organisms in a changing climate, move

A

shift range poleward (or to higher elevations) following rising isotherms

127
Q

organisms in a changing climate, acclimate

A

survive outside of normal range organisms previously existed
dependent on plasticity

128
Q

organisms in a changing climate, adapt

A

over multiple generations

  • evolve w/i existing phenotype
  • evolve through genetic mutation
129
Q

organisms in a changing climate, die

A

locally, regionally, or globally extinct

130
Q

terrestrial organisms are shifting how much

A

2-3X faster than previously reported
17km/decade poleward
11m/decade vertically

131
Q

marine organism range shifts

A

190+/- 38 km/decade SE

132
Q

changes in fish assemblage at fixed locations

A

smaller, faster growing fishes increasing (sculpin, hagfish, cod)
larger fish decreasing (pout, pollock, haddock, ray)

133
Q

changes in plankton with climate change

A

biomass peaks occurring earlier

mismatch with timing of predators (migrating, reproducing)

134
Q

what happens to the ocean with an increase in CO2

A

increased acidity

CO2 + H20 - HCO3- + H+ – CO3^2- + 2H+

135
Q

Bjerrum plot

A

concentration vs. pH

CO2 peak – HCO3 peak – CO3 2-

136
Q

current seawater pH

A

ca. 8

137
Q

pH =

A
  • log [H+]

add CO2, increase H, decrease pH

138
Q

problems with low pH

A

hard on shell-builders (coccolithophores, pteropods, corals, shellfish) that are important to marine food web and economically

139
Q

onshore vs offshore pH

A

Onshore regions lower pH than offshore due to upwelling of lower pH waters

140
Q

USA shellfish economic value

A

$270M
3200 jobs
threatened by ocean acidification

141
Q

Canada shellfish economic value

A

> 12,000t oysters annually

>$18M / yr

142
Q

oxygen changes in the ocean

A

w/ increasing T and CO2 = decreasing O2

143
Q

in low O2 environment

A

have to work harder to obtain O2 and to expel CO2 (lower pO2, high pCO2)
Optimum aerobic performance can not be maintained – fitness window becomes narrower, and peak performance decreases

144
Q

most likely increase in T by 2100

A

3ºC

145
Q

Increase in sea level since pre-industrial

A

ca. 0.25m

146
Q

expected sea level rise by 2100

A
RCP2.6 = 0.65m
RCP8.5 = 1m
147
Q

Ωarg

A

degree to which seawater is saturated with aragonite

148
Q

changes in Ωarg

A

∆[carbonate ion] results in ∝change in Ωarg; ocean acidification = decline in Ωarg = harder for marine calcifies to precipitate skeletons/shells

149
Q

Energy flow in marine ecosystem

A

sun - PP - SP - carnivores

all stages transfer E to decomposers

150
Q

mineral cycling in marine ecosystems

A

(PP - SP - Carnivores) - Decomposers - Nutrients - PP

151
Q

What is a trophic pyramid

A

size of each layer represents relative biomass of organisms at that trophic level

152
Q

trophic level

A

group of organisms occupying same position in a food web

153
Q

Amount of E available to higher trophic levels depends on

A

Amount of PP
TTE
# of trophic levels

154
Q

e.g. of trophic levels being dependent on PP

A

Highly productive waters (NW Atl) have higher fish/squid populations
low productivity waters (Baltic) have low carnivore #s

155
Q

Types or marine food chains

A

oceanic type
coastal type
upwelling type

156
Q

upwelling type food chain

A

microphytolankton - pelagic :(macrozoop. - zooplanktiverous fish - piscivorous fish)
benthic (benthic herbivores - benthic carnivores - piscivorous fish)

157
Q

upwelling type food chain

A

macrophytoplankton - (planktiverous fish)

megazooplankton - planktiverous whale

158
Q

nanaoplankton

A

flagellates

159
Q

oceanic piscivorous fish

A

tuna, squid

160
Q

benthic herbivores

A

clams, mussels

161
Q

planktiverous fish

A

anchovy

162
Q

megazooplankton

A

krill

163
Q

macrozooplankton

A

copepods

164
Q

megazooplankton

A

chaetognaths

165
Q

zooplanktiverous fish

A

herring

166
Q

oceanic type food chan

A

nanoplankton - microzooplankton - macrozooplankton - megazooplankton –zoplanktivorous fish - piscivorous fish

167
Q

benthic carnivores

A

cod

168
Q

coastal piscivorous fish

A

salmon, shark

169
Q

microphytoplankton

A

diatoms, dinoflagellates

170
Q

Mean PP: Oceanic, coastal, upwelling

A

O: 75 gC/m2/yr
C: 300
U: 500

171
Q

number of E transfers between trophic levels: Oceanic, coastal, upwelling

A

O: 5
C: 3
U: 1.5

172
Q

Average TTE: oceanic, coastal, upwelling

A

O: 10%
C: 15%
U: 20%

173
Q

mean fish production: o, c, u

A

O: 0.75 mgC/m2/yr
C: 1000
U: 44, 700

174
Q

Microbes in the ocean

A
phytoplankton/algae
fungi (rare, poorly known)
protozoa (flagellates, ciliates)
archaea (poorly known)
bacteria (mainly heterotrophs)
Viruses (phages, animal viruses)
175
Q

Virus size

A

0.01-0.2µm

176
Q

Marine prokaryotes

A

Eubacteria, Archaea
single celled, no nucleus, very small
most of genetic diversity on Earth

177
Q

where are Eubacteria found

A

water column

sediments

178
Q

where are Archaea found

A

in extreme environments

179
Q

Bacterial cell densities in marine environment

A

Estuary: >5x10^6 cells/mL
Coastal: 1-5x106
Open ocean: 0.5-1x10^6
deep sea: less than 0.01x10^6

180
Q

typical bacteria density in ocean

A

10^5-10^6/mL

181
Q

overall concentration of bacteria in ocean

A

1.6x10^29

182
Q

prokaryote sizes

A

0.2-1µM

Bacteria, Archae

183
Q

amount of bacteria that are heterotrophic

A

90-95%

184
Q

amount of organic C in ocean that is heterotrophic bacterial

A

70%

185
Q

amount of organic C in ocean that is bacterial

A

90-95%

186
Q

eukaryote microbe sizes

A

1-200µM

Algae, protozoa

187
Q

when were marine bacteria recognized as important

A

1970s

188
Q

why was it hard to recognize bacteria in the ocean

A

small - need microscopy

culturing - not useful for marine

189
Q

scientific advancements that allowed the recognition of marine bacteria

A

fluorescent dyes that bind to nucleic acids

190
Q

now we count/ID bacteria using

A

epifluorescence microscopy

flow cytometry

191
Q

what happens to bacteria in the ocean

A

consumed by other plankton

lysed by viruses

192
Q

lysis

A

the disintegration of a cell by rupture of the cell wall or membrane

193
Q

what do heterotrophic bacteria eat

A

primarily DOM

from: phytoplankton fluid, excretory products, viral lysed cells, sloppy feeding left overs

194
Q

DOM

A

dissolved organic matter

passes through 0.45µm filter

195
Q

DOC

A

dissolved organic carbon

primary component of DOM

196
Q

Microbial loop

A

fish - zooplankton - ciliates - micro flagellates - bacteria - remineralization - nutrients

197
Q

Marine viruses

A

no metabolism, inject genetic material into host and force replication, most abundant life in ocean, ubiquitous

198
Q

marine viruses known since

A

1990s

199
Q

typical marine virus concentrations

A

10^7 - 10^11/mL

order of magnitude more than bacteria

200
Q

rate of marine viral infections

A

ca. 10^23 infections /second

201
Q

Marine virus habitat

A

greatest abundance in surface (upper 200m), nearshore

202
Q

why are the majority of viruses in the surface

A

because thats where the majority of hosts are

203
Q

main marine viral infections

A

heterotrophic bacteria = bacteriophages

204
Q

ecological role of marine virus

A
bacterial mortality (including HAB)
major biomass turnover
205
Q

ecological role of marine heterotrophic bacteria

A

nutrient cycles - remineralization
microbial loop
pollution remediation

206
Q

When did the Atlantic cod population collapse

A

1980

catastrophic in 1992

207
Q

Cod

A

demersal, longlived (20+yrs), early maturity (2-4yrs), omnivorous, broadcast spawn, highly fecund, soniferous, easy to dry and salt

208
Q

demersal

A

living close to the floor of the sea

209
Q

East coast high productivity

A

front where Gulfstream meets Labrador current

210
Q

Georges bank prey

A

phytoplankton
flagellates
ciliates
copepod nauplii

211
Q

Georges bank target species

A

Copepods
haddock larva
cod larva

212
Q

Georges bank predators

A
euphausiids
hydroids
amphipods
chaetognaths
ctenophore
siphonophore
medusa
herring
mackerel
213
Q

early cod fish harvesting methods

A

handline
longline
gillnet

214
Q

Cod fisheries, 1700

A

shipped to europe
linked to slavery, sugar cane, rum
helped start American revolution ($)

215
Q

effects of bottom trawling

A

total destruction of deep sea habitats

216
Q

fishing technology

A

steam powered trawl vessels catch 6X faster

diesel powered even more efficient

217
Q

amounts of fish harvested

A

1920s - 1250,000t
1960- 200,000t
1965- 760,000t
populations declining 1966-1970

218
Q

why didn’t fishing stop with declining populations

A

weak regulations, poorly enforced, insufficient

219
Q

solution to the overfishing

A

extend fishing grounds from 12-200nautifcal miles (EEZ)

220
Q

Fish stocks 1980

A

haddock, yellowtail flounder stocks collapse
rely entirely on cod
landings drop from 1.6bill-220mil to 1991

221
Q

changes to allowable fishing after 1991

A
1994 new rules
license moratorium
reduced allowable days at sea (DAS)
closed portions of Georges Banks
new fish, mesh size restrictions
designed to reduce fishing efforts 50% over 5-7yrs
222
Q

total cod harvested from NWFL

A

100milliont
1/2 1500-1900
1/2 1900-2000

223
Q

expected recovery after 1993 reduction in fishing effort

A

not yet occurred

224
Q

why aren’t cod recovering

A

shrimp, crab catch has gone up significantly

225
Q

took over new niche space opened up by cod

A

groundfish - pelagics - crustaceans

226
Q

coastal zone

A

narrow strip of ocean from edge of continental shelf to the estuaries
waters less than 200m

227
Q

coastal zones are how much of ocean surface

A

7%

228
Q

coastal zones are how much of ocean volume

A

much less than 0.5%

229
Q

importance of coastal waters

A

most biologically productive parts of worlds ocean
nutrient-rich, high PP
major role in biogeochemical cycling
most of worlds greatest fisheries

230
Q

anti-cyclonic retention cycle

A

meeting of currents = anticyclonic gyre; productivity due to frontal zone, larvae retained in gyre, make way down to rocky bottom; Nutrients not upwelled but larvae returned

231
Q

coastal processes complicated by

A

shallowness
freshwater input
tidal currents
upwelling events

232
Q

organic carbon in coastal ocean compared to open oceans

A

8-30X more Corg

233
Q

coastal ocean Corg burial

A

80% of Corg buried in coastal zone

large % of CaCO3 and SiO2 also deposited

234
Q

coastal zone production

A

14% of total global
80-90% of new production
50% of denitrification

235
Q

productivity of river/estuarine plume

A

high PP due to increased nutrs. and light levels; where fresh water meets the seawater mixing causes entrainment of particles from deeper water in to the surface = small-scale upwelling

236
Q

increased bio activity from plumes due to river input

A

increased turbidity and nutrient enrichment from river (particles, sediment, nutrients)

237
Q

increased bio activity at plumes from seawater input

A

nutrient entrainment and upwelling

238
Q

increased bio activity from plumes due to stability

A

enhanced stability due to freshwater/dense water layering

239
Q

importance of estuaries

A
Among most productive enviro.s on E
high PP
nursery grounds
economically relevant
important associated environments
240
Q

important environments associated with estuaries

A

salt-marshes

mangrove swamps

241
Q

where are mangrove swamps

A

coastal zones near equator, around N half of Australia

242
Q

where are salt marshes

A

N coast of Europe, Asia
E/W coasts of US
SE coast SA

243
Q

North Atlantic conditions

A
Warm (8.5ºC at depth in winter)
Very low N in summer
No Fe limitation
Large # diatoms, photosynthetic dinofl., benthic fish
HCLN
poor phyto/zoo coupling
high phyto. export
244
Q

North Pacific conditions

A
Cold (3.8ºC at depth in winter)
High nutrients yr round
Iron limited
Large # small photosyn. flagellates, large # pelagic fish
HNLC
close phyto/zoo coupling
low phyto. export
245
Q

dominant N Atl copepod

A

Calanus finmarchicus

246
Q

dominant N Pac copepod

A

Neocalanus plumchrus

247
Q

C finmarchicus cycle

A

surface before fully developed (low fitness), no significant impact on phyto., feed - grow - lag in bloom; up and down through summer, lower pressure on phyto.

248
Q

N. plumchrus

A

cover water = reserves = greater fitness, surface as adults, keep phyto in-check through summer, much greater impact

249
Q

how life stage affects ability to graze bloom

A

C finmarchicus

need to grow and gain energy before able to graze to full potential

250
Q

concentration vs distance from shore

A

estuary/inner shelf = high nut., phyto bloom, decrease in euphotic zone depth
outer shelf/open ocean = low phyto., low nutrients, low euphotic zone depth

251
Q

HOTS

A

Hawaiian Ocean Time-series Study (NPCG)

252
Q

BATS

A

Bermuda Atlantic Time-series Study (Sargasso Sea)

253
Q

HOTS/BATS

A
very low productivity
no upwelling 
very stable systems
permanent thermoclines
low, but very deep productivity
254
Q

subtropical gyres

A

anti-cyclonic flow

convergent - water piles in center, stabilizes, warm, oligotrophic

255
Q

subtropical gyre temperatures

A

surface layer: ca. 18ºC (winter) - 25ºC (summer)

256
Q

subtropic gyre thermocline

A

seasonal: 50-70m
permanent: ca. 125m

257
Q

subtropic gyre productivity

A

Net photosynthesis positive, nitrate depleted, phosphorus nearly depleted to ca. 125m

258
Q

oligotrophic

A

low nutrients
low productivity
high oxygen

259
Q

subtropic gyre chl max

A

deeper than other systems (like temperate, subarctic, coastal)

260
Q

why is chl max deep in subtropic system

A

low vertical mixing leaves high nutrients at depth

60% of deep phytoplankton is cyanobacteria

261
Q

why was there found to be a high % of cyanobacteria in tropical systems

A

N2 fixers

262
Q

nitrogen fixing cyanobacteria

A

Trichodesmium

263
Q

Why is N2 fixation high in Sargasso Sea

A

N Africa aeolian dust (Fe)

264
Q

Affect of N2 fixation on redfield ratio

A

larger supply of N so P becomes limiting factor

e.g. N:P Sargasso = 17:1 (BATS)

265
Q

key feature of subtropical gyre

A

water column stability

266
Q

Tropic mesozooplnkton

A
continuously active
no seasonal rest phase
diverse
low biomass
keep production nearly in balance
267
Q

Normal conditions in the equatorial Western Pacific

A

low pressure
rising air
cloudy/rainy
trade winds come from the East

268
Q

normal conditions in equatorial eastern pacific

A

high pressure
sinking air
clear, dry weather
trade winds blow to the West

269
Q

Equatorial Pacific trade winds

A

southeast, move from E–>W, cause Peruvian upwelling, creates a warm ‘pool’ of water along W Pac

270
Q

main places N2 fixation occurs

A

**Sargasso Sea

NPCG (NP Central Gyre)

271
Q

what happens during ENSO

A

winds change direction - upwelling shuts down

272
Q

Effects of ENSO

A

change in productivity, fishery yield, mammals/birds, weather patterns, global climate, alter jet stream, harmful and beneficial results

273
Q

frequency of ENSO

A

2-10 yrs

274
Q

ENSO index

A

weighted average of atmospheric and oceanic factors, shows alternating patterns of El Niño - La Niña conditions

275
Q

factors involved in ENSO index

A

atmospheric pressure, winds, SST, etc

276
Q

TAO project

A

Tropical Atmosphere Ocean project

monitors equatorial Pacific with ca. 70 moored buoys for detection, understanding, and prediction of El Niño

277
Q

southern oscillation

A

atmospheric component of El Niño; oscillation in surface air pressure between E/W Pac

278
Q

what was the strongest ENSO in recorded history?

A

1997/98 and 2015/16 both had ONI = 2.3

279
Q

Anoxic/hypoxic water examples

A

Saanich Inlet
Norther Gulf of Mexico
The Oregon Coast
St. Lawrence Estuary

280
Q

Saanich Inlet

A

hypoxia develops periodically (naturally)

has been occurring for ca. 10,000yrs

281
Q

hypoxia

A

reduced oxygen content of air or water detrimental to aerobic organisms

282
Q

development of hypoxia

A

high OM production in surface - high vertical transport of OM to deep - high remineralization of OM by heterotrophic bacteria (consumes O2)

283
Q

high productivity in SI

A

coastal upwelling brings dense nutrient rich water into Strait of Georgia

284
Q

hypoxia in SI develops because

A

sill blocks oxygenated water from entering

285
Q

SI renewal

A

eventually dense O2 water builds up, spills over sill, and re-supplies oxygen

286
Q

Hypoxia in Gulf of Mexico caused by

A

excess N delivered by Mississippi (drains majority of country) + stratification of Gulf waters

287
Q

Is Gulf of Mexico anoxia anthropogenic

A

yes - widespread fertilizer use = high nutrient = high PP = high OM flux..

288
Q

Oregon coastal water

A

hypoxic events occurring since 2002

upwelling zone, strengthening from intensified winds, bringing deeper water with lower O2 to surface

289
Q

St. Lawrence estuary

A

waters are a mixture of N/S waters, the mixture is changing to more of the warm water/low O2 source

290
Q

St. Lawrence water sources

A

LCW - Labrador coastal water (cold and oxygenated)

NACW - North Atlantic Coastal Water (warm, low O2)

291
Q

St. Lawrence water source ratio

A

1930: 72% LCW, 28% NACW
1985: 53% LCW, 47% NACW

292
Q

Why is St. Lawrence changing

A

change in circulation patterns

low O2 is exacerbated by human use of fertilizer

293
Q

example of naturally occurring hypoxia/anoxia

A

SI

294
Q

Is Oregon coast hypoxia natural

A

no, considered anthropogenic because wind pattern changes are a result of climate change