Chapter 3- The Aquatic Environment
The turnover time for atmospheric water is
.024 year
oxygen in water reaches a maximum solubility of ____ in freshwater at a temperature of 0C
1%
___ oxygen in water
1% oxygen
pressure increases 1 atm for each ____m in depth in water
10m
H+:OH-
1:1 ratio for water
ph range of natural waters is between
2-12
ocean salinity
35%
maximum density of water occurs at
4 degrees C
most organisms cannot reproduce below pH
4.5
most organisms cannot survive and reproduce at a pH below
4.5
the entire water content of the atmosphere is replaced on average every
9 days
At a high pH, more CO2 is present as
CO3 2-
surface runoff
During heavy rains when the soil is saturated, excess water flows across the surface of the ground
At neutrality (pH 7), most of the CO2 is present as
HCO3 -
light attenuation
The change in the wavelength with the depth
When do whitecaps form?
When the waves reach a point where energy from wind equals energy lost by breaking waves
estuary
Where freshwater meets saltwater
high specific heat is important because it acts as
a buffer for heat change, both internally and externally
the system acts as a buffer by
absorbing hydrogen ions in the water when they are in excess (producing carbonic acid and bicarbonates) and producing them when they are in short supply (producing carbonate and bicarbonate ions)
pH of less than 7
acidic
The greater the number of H+ ions, the more
acidic the solution is
seawater is slightly _____
alkaline 7.5-8.4
sodium, potassium, and calcium are
alkaline ions
Aquatic organisms are unable to tolerate low pH conditions largely because acidic waters contain high concentrations of
aluminum
acidic waters contain high concentrations of
aluminum
Bicarbonate may further dissociate into
another hydrogen ion and a carbonate ion
oxygen is not distributed ___ ____ in oceans
as evenly because of the movement in the ocean
oxygen diffuses from _____ to ______
atmosphere (high) to surface waters (low)
____ light travels the deepest
blue
the carbon dioxide-carbonic acid-bicarbonate system functions as a
buffer to keep the pH of water within a narrow range
as co2 in ocean rises,
calcium carbonate decreases
Colder water increases oxygen solubility. Formation of ice, however
can greatly reduce diffusion from atmosphere into surface waters
Upon diffusing into the surface, carbon dioxide reacts with water to produce
carbonic acid (H2CO3)
why do we have tides
centrifugal force from the moons gravitational pull, creates a bulge
surface tension is caused by
cohesive forces within a liquid
hypolimnion
coldwater o2 poor
The availability of oxygen in aquatic environments characterized by flowing water is different.
constant churning of stream water over riffles and falls gives greater contact with the atmosphere; the oxygen content of the water is high,
temp affects stream community structure
cool water vs warm water organisms
in the winter time, surface water is _____ than the bottom water
cooler because below 4C water becomes less dense and rises to the surface
how is estuary water mixed
currents and winds
solubility _______ as salinity increases
decreases
the solubility of a gas in water ______ as the temperature rises
decreases
turnover
deeper water is recharged with oxygen
decline in oxygen reflects the
demand and uptake by decomposer organisms inhabiting the bottom zone
formation of ice can greatly reduce
diffusion from atmosphere into surface waters
As a result, the amount of light reflected from the water surface will vary both
diurnally and seasonally between the equator and the poles
latent heat
energy released or absorbed in transforming water from one state to another
over oceans, ______ exceeds ____
evaporation exceeds precipitation
transpiration
evaporation of water from internal surfaces of leaves, stems, and other living parts
vertical water temp is the least variant in the
fall
the stream's character changes from
fast water to slow
estuary temps _______ daily and seasonally
fluctuate
at low pH, more CO2 occurs in the
free condition
carbon dioxide-carbonic acid-bicarbonate system result in the production of
free hydrogen ions
saturation value of oxygen is _____ for cold water than warm water
greater
ph indirectly influences through
heavy metal concentration
water has a _______ viscosity relative to air
high
watersheds dominated by limestone caco3
higher ph and well buffered
evaporation is governed by
how much water vapor is in the air relative to the saturation vapor pressure
Carbonic acid further dissociates into a
hydrogen ion and a bicarbonate ion:
high tides occur when the moon is
in line with the sun, either side of earth
At high tide, the incoming seawater ______ the salinity toward the river mouth.
increases
solubility _______ as atmospheric pressure increases
increases
aluminum is _____ in neutral or alkaline waters
insoluble
the figure shows that in an estuary, near the mouth of a river, salinity
is lower at low tide and higher at high tide
Water's high viscosity relative to that of air is largely the result of
its greater density
sperm whale body shape purpose
its shape meets the least water resistance
Oxygen declines sharply in the thermocline and is nonexistent on the bottom because of
its uptake by decomposer organisms in the sediments
As a result, salinity is higher on the
left side
ocean acidification effects
less calcium carbonate mean organisms cant create their shells (when they die it breaks down the structure of the entire food web) animal chemical signaling is impacted
water is ____ dense and ___ stable as a solid
less dense and more stable
Salinity increases with depth because
lighter freshwater flows over denser saltwater
deep sea creature characteristics
longer life span large eyes
watersheds dominated by sandstone or granite
lower ph, less buffered
When frozen, water molecules occupy ____ space than they do in liquid form
more
high tide shoreline brings in ____ salinity to the river mouth
more
longer wavelength of red light bumps into _____ particles than blue light
more
saltwater is _____ dense than freshwater
more
how do waterfalls on mountains stay supplied
more precipitation than river flow and transpiration evaporation
because of infiltration, certain amounts of water
never get filtrated but instead evaporate
Even under ideal conditions, gases are ____ soluble in water.
not very
Along the western edges of the continents, the Coriolis effect causes the surface waters to move
offshore
water temp rises as water in a stream runs through
open meadows
colder water can hold more
oxygen
less metabolic activity in organisms in deeper organisms because
oxygen is a limiting factor for their metabolism
during spring and fall turnover, water recirculates, causing
oxygen to be replenished in deep water
carbon dioxide-carbonic acid-bicarbonate system directly affect the
pH of aquatic ecosystems
low tides occur when the moon is
perpendicular with the sun
Addition or removal of CO2 affects ___ , and a change in pH affects ___
ph co2
ph directly influences
physiological processes
which of these is the largest reservoir of freshwater on earth
polar ice caps and glaciers
interception
precipitation intercepted by vegetation, dead organic matter, or urban structures
infiltration
precipitation that reaches the soil and moves into the ground
thermocline
rapid temp change light attenuation drop off 02 decreases
water absorbs some wavelengths more than others
red wavelengths
concentration of oxygen in aquatic environments often limits
respiration and metabolic activity
In all estuaries of the Northern Hemisphere, outward-flowing freshwater and inward-flowing seawater are deflected to the
right
the waters with the lowest salinity are at the
river mouth
____ underlying a watershed affect its ph
rocks
ph of watersheds is largely dependent on the
rocks it flows over
Determination of the most abundant element, chlorine, is used as an index of
salinity
when the winds are still, the river water flows ______ on a shallow surface over an _____ movement of seawater
seaward upstream
tidal overmixing
seawater on the surface tends to sink as lighter freshwater rises, and mixing takes place from the surface to the bottom
Is it the shorter or longer wavelengths of visible light that penetrate the deepest into the water column?
shorter
turnover formula
size of reservoir / rate of evaporation
driving force behind the water cycle
solar radiation
The rate of diffusion is controlled by the
solubility of oxygen in water and the steepness of the diffusion gradient
acidity tend to ____ in aquatic environments
stabalize
thermocline is mainly only present in the
summer
in the summer, oxygen is greatest at the
surface
evapotranspiration
surface evaporation plus transpiration
Once oxygen enters the surface water, the process of diffusion continues, and oxygen diffuses from the
surface to the waters below (because of their lower concentration)
The amount of light entering the water surface is further reduced by two additional processes.
suspended particles intercept light by absorbing/scattering water absorbs light
triple point of water
temperature and pressure at which water will coexist as a solid, liquid, gas.
thermal stratification
temperature changes sharply with depth
Oxygen is lost from the water as
temperatures rise and through the uptake of oxygen by aquatic life.
small stream temps
tend to follow, but lag behind, air temps
transmittance
the ability of light to pass through a medium
amount of light reflected from the surface of the water depends on
the angle at which the light strikes the surface
capillary action
the combined force of attraction among water molecules and with the molecules of surrounding materials to go up a thin tube
oxygen increase below the oxygen minimum zone of ocean may be the result of
the influx of cold, oxygen-rich waters that sank in the polar waters.
the waters with the highest salinity are at
the sea
Movement of the surface waters offshore results in an upwelling of deeper, colder waters to
the surface next to the western edge
water molecules on the surface are pulled downward because
they have a stronger attraction to the water molecules below them than the atmosphere above
neap tides
tides with minimum daily tidal range that occur during the first and third quarters of the moon
Evaporation from the oceans exceeds precipitation into the oceans. Which of these processes or parts of the water cycle does not contribute water to the oceans?
transpiration by marine algae
three estuary types in nc
tributary trunk back barrier sound
rate of infiltration depends on
type of soil, slope, vegetation, and precipitation intensity
carbon dioxide carbonic acid bicarbonate system
used as a buffer in aquatic environments
the temp of a flowing body of water is
variable
estuary salinity varies ______ and ____
vertically and horizontally
epilimniom
warm water 20-30 ft o2 rich
large stream temps
warmer parts are exposed to sunlight, cooler parts are shaded by trees
How is the loss of water in the ocean balanced
water evaporated from the ocean is precipitated on land where it returns to the ocean in rivers
what types of water are evaporated
water on the surface of the ground in the upper layers of soil on the surface of vegetation surface layers of streams, lakes, and oceans
fish need less structural support and can be large because
water reduces the effect of gravity
wind generates
waves
coriolis effect is at work with
waves (upwelling)
we can grow a lot of plants similar to japanese plants because
we have the same soil/structure metamorphis granitic rock
solar tides are ______ than lunar tides
weaker
Because the Sun has a weaker gravitational pull than the Moon does, solar tides are partially masked by lunar tides—except for two times during the month:
when the Moon is full and when it is new