Water in the OceanWater in the Ocean

Water propertiesWater propertiesOrganisms and waterOrganisms and water

PressurePressureTemperatureTemperatureLightLightChemistryChemistry

O2O2CO2CO2CaCO3CaCO3SalinitySalinity

Life in the waterLife in the water

WaterWaterWater molecule: electric dipoleWater molecule: electric dipole

Salinity: dissolved solidsSalinity: dissolved solids35ppk: marine water35ppk: marine waterResidence times of elementsResidence times of elements

Amt (g) Resid tNa 147 X 1020 2.6 X 108

K 5.3 X 1020 1.1 X 107

Ca 5.6 X 1020 8.0 X 106

Si 5.2 X 1018 1.0 X 104

Mn 1.4 X 1015 7.0 X 103

Fe 1.4 X 1016 1.4 X 102

Al 1.4 X 1016 1.0 X 102

Not cumulativeNot cumulativeRemoval:Removal:

SedimentsSedimentsOrganismsOrganismsMineral precipitationMineral precipitationSea spraySea spray

WaterWaterLiquid is fluid. Liquid is fluid.

Fluid will change shape as force is appliedFluid will change shape as force is appliedGas is also fluid, but fills space; liquid has surfaceGas is also fluid, but fills space; liquid has surface

Density Density

How tightly packed are moleculesHow tightly packed are moleculesPure H2O: 1.0 g/cm^3 Pure H2O: 1.0 g/cm^3 Seawater: 1.02-1.03 g/cm^3Seawater: 1.02-1.03 g/cm^3T, salinity affectsT, salinity affectsWater is unusual in Water is unusual in changes changes

ViscosityViscosityResistance to change in shapeResistance to change in shapeImportant to microorganismsImportant to microorganisms

Organism Sizes and Organism Sizes and WaterWater

Large size: control movement, food contactLarge size: control movement, food contactSelf-propelled: Buoyancy, swimmingSelf-propelled: Buoyancy, swimmingHunting, scavenging, grazingHunting, scavenging, grazing

Small size: water has huge effectSmall size: water has huge effectViscosityViscosityLtd propulsion: Migration, currents, settlingLtd propulsion: Migration, currents, settlingBoundary layer: microorganisms, filter feedersBoundary layer: microorganisms, filter feeders

PressurePressureVertical variability: 1 atm per 10 mVertical variability: 1 atm per 10 mStatic variability: can change with tidesStatic variability: can change with tidesStenobaric, eurybaricStenobaric, eurybaric

May or may not effect benthos, May or may not effect benthos, but have to deal with it!but have to deal with it!

Some fish limited by pressureSome fish limited by pressureexamples: coelocanth, deep sea fish examples: coelocanth, deep sea fish

TemperatureTemperatureTropics: Constant: 30CTropics: Constant: 30CDeep water: Constant: 4CDeep water: Constant: 4CEverywhere else, variable.Everywhere else, variable.

Fluctuations depend on: Fluctuations depend on: mixingmixingdaily T fluxdaily T flux tidestides

ThermoclineThermoclineEffects:Effects:

OxygenOxygenCaCO3CaCO3Nutrient uptakeNutrient uptakeActivityActivity

Eurythermal, stenothermalEurythermal, stenothermal

0 5 10 15 20 25 300

4km

Equator

Tropics

Polar

LightLightVery important to Very important to primary producers, primary producers, visual sensesvisual senses

Red end of spectrum Red end of spectrum absorbed in upper 10mabsorbed in upper 10mBlue scatteredBlue scattered

Photic zone: depends on Photic zone: depends on turbidity (suspended turbidity (suspended particles, cloudiness)particles, cloudiness)

Shoreline: <1mShoreline: <1mOpen ocean: ~60mOpen ocean: ~60mTropical reefs: ~80Tropical reefs: ~80

Absolute depth, clear Absolute depth, clear water: 1000kmwater: 1000km

OxygenOxygenTerms: Anoxic/anaerobic – no O2Terms: Anoxic/anaerobic – no O2

dysoxic/dysaerobic – low O2dysoxic/dysaerobic – low O2oxic/aerobic -- oxygenatedoxic/aerobic -- oxygenated

Oxygen saturation changes with T, t, DOxygen saturation changes with T, t, D

3ppm: limiting3ppm: limiting5ppm: “safe” 5ppm: “safe”

Oxygen continuedOxygen continuedSources:Sources:

AtmosphereAtmospherePlantsPlants

Sinks:Sinks:DecompositionDecompositionRespiration (animals and plants)Respiration (animals and plants)Chemical reactionsChemical reactions

Mechanisms of O2 movement:Mechanisms of O2 movement:DiffusionDiffusionConvectionConvection

Diurnal surface O2 variation: TDiurnal surface O2 variation: TMorning: 85%; afternoon: 115%Morning: 85%; afternoon: 115%

Seasonal variationSeasonal variationShallow: April: 150% saturationShallow: April: 150% saturation

high photosynthesis + low decomp.high photosynthesis + low decomp.August: 42% saturationAugust: 42% saturation

Deep: T control, detrital rainDeep: T control, detrital rainJune: 24% saturationJune: 24% saturationOct: 133% saturationOct: 133% saturation

Chesapeake BayChesapeake Bay

CO2 and CaCO3CO2 and CaCO3(Carbon Dioxide and Calcium (Carbon Dioxide and Calcium

Carbonate)Carbonate)

H2O + CO2 H2CO3 Carbonic Acid

H2CO3 H+ + HCO3- Bicarbonte ion

H+ + HCO3 2 H+ + CO32- Carbonate ion

Calcite (Calcium Carbonate) and CO2

CO2 + H2O + CaCO3 Ca2+ + 2 HCO-

carbon dioxide + water + calcium carbonate calcium + carbonic acid

CaCO3CaCO3

Cambrian

Ordovician

Silurian

Devonian

Mississippian

Pennsylvanian

Permian

Triassic

Jurassic

Cretaceous

Tertiary

Quaternary

540

248

65

504

438

408

360

320

286

202

144

5

GlacialPeriods

SeaLevel RCO2

High frequencysea-leveloscillation

High frequencysea-leveloscillation

CaCO3

Millions ofyears ago

age ofproposedstudy

Av global T

2 phases: 2 phases: calcite (stable) calcite (stable) aragonite (unstable)aragonite (unstable)

Acroporamodern

SyringoporaCarboniferous

SalinitySalinityDissolved solidsDissolved solidsOcean water: 35 ppkOcean water: 35 ppk

0-1ppk at fresh water input (hyposaline)0-1ppk at fresh water input (hyposaline)to 150 ppk in evaporative systems to 150 ppk in evaporative systems

(hypersaline)(hypersaline)Sediments bufferedSediments bufferedVariability from:Variability from:

TidesTidesSeasonality: precipitationSeasonality: precipitationUnpredictable stormsUnpredictable storms

Salinity changes densitySalinity changes densityAnimals:Animals:

Stenohaline vs. euryhalineStenohaline vs. euryhalineDirect effects: osmosisDirect effects: osmosisIndirect effects: buoyancy Indirect effects: buoyancy

How does living on land differ fromHow does living on land differ fromliving in the water?living in the water?

Living in the WaterLiving in the WaterOn land:On land:

Need structure for gravityNeed structure for gravityAir less denseAir less denseRespiration, movement, heat loss/gain on Respiration, movement, heat loss/gain on

landlandNeed water for respiration, reproductionNeed water for respiration, reproductionVision, hearingVision, hearing

In water:In water:Buoyancy, supportBuoyancy, supportDense waterDense waterMore O2; drag forces; heat loss/gain in More O2; drag forces; heat loss/gain in

waterwaterVision, hearingVision, hearing

Anableps dovii, Anableps dovii, the four-eyed fishthe four-eyed fish

Fish Morphology Fish Morphology and Depthand Depth