Transcript Inland Waters - Diablo Valley College

This week:
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Inland seas
Homework 2
Wednesday – UC Botanical Garden
Next Monday: Exam 2 includes:
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History of Conservation
Animal groups
Geology
Central Valley, Riparian
Inland Seas, Lakes, Rivers
Inland Waters
Fresh Water a precious
resource
Freshwater Systems
Ecological Services
Economic Services
• Climate moderation
• Food
• Nutrient cycling
• Drinking water
• Waste treatment
and dilution
• Irrigation water
• Flood control
• Groundwater
recharge
• Habitats for aquatic
and terrestrial
species
Importance of
Fresh Water
areas
• Hydroelectricity
• Transportation
corridors
• Recreation
• Employment
• Genetic resources
and biodiversity
• Scientific
information
Fig. 24.5, p. 633
Slide 5
Fresh Waters
• Surface waters run off, down hill
• All area that collects water forms a
water shed for a river, delta, bay
• Source zone
– High oxygen levels, clear water
– fast moving head waters, waterfalls
• Transition zone
• Floodplain zone
– Muddy water
– Low oxygen levels
River Zones
Rain and snow
Lake
Glacier
Rapids
Waterfall
Tributary
Flood plain
Oxbow lake
Salt marsh
Delta
Ocean
Deposited
sediment
Source Zone
Transition Zone
Water
Flood-Plain Zone
Sediment
Our Watershed
• Drains to
Carquinez Straits
Lakes - water collects in a
catch depression
Lake type determine by how it formed:
• Glacial
• Tectonic
• Landslide
• Volcanic
• Fluviatile
• Shoreline
• Terminal or Closed basin
Glacial Lakes
• Glacial action- Common in Sierras
• Tarns (lakes) formed by glacier action
leaving low spots in bed rock– Pater Noster- series of cirques (tarns with high
vertical back wall) down a mountain
• Moraine lakes- impeded by moraine.
– May have a blue color due to suspended rock
particles
– Common on east side of Sierras
• Kettles form as holes in the moraine field
Tarn
Cirque
Pater Noster
Kettle
Tectonic process –
uplifting, and depressions in
dip-slip Faults
• Graben (grave) lakes
– Lake Tahoe (1). Original lake formed
between two blocks of stone as fault
slipped down.
– Livermore Valley - gravels
Lake Tahoe
Volcanic Lakes
• Lava flows blocks water flow
• Common along faults, often form in
conjunction with tectonic (as in Tahoe)
• Clear lake - Dammed by lava.
– Two arms fill in grabens.
• Current form of Lake Tahoe (2)
– Was deepened by lava flow at Truckee end.
• Caldera Lake forms when a volcano blows
off its summit and leaves the sunken
caldera which fills with water.
– Crater lake in Oregon, deepest in US.
• Small surface area restrict evaporation – stays full
with winter rains/snow
Crater Lake
Landslide lakes• Rock, Mud flow traps flow, raises
water level
• Mirror lake in Yosemite. Several on
Kern River.
• Often short lived as water digs in
new channel.
• Often form in narrow river canyons.
• Caused by mudslides or
earthquakes.
Fluviatile - From in depression
formed by flowing water
• Ox Bow lakes - cut off from main
channel.
• River Dam lakes - Sediment flowing
down a tributary blocks main
channel.
– Kings River sediment blocked flow
North up San Joaquin valley.
– Tulare river flows south, formed lake
Tulare.
Shoreline • impounded by barriers of sand by
wind and waves at River mouths.
• maybe seasonal
• Can break quickly– a tourist drowned in San Lorenzo River at Santa Cruz, washed out to sea.
– We’ll see a small lake at Salmon Creek
beach
Terminal or Closed basin
• Watershed with no outlet
– Dependent on inflow vs. evaporation rates
• Mono Lake-Oldest lake in California
– Hypersaline, accumulating solutes for
thousands of years
– Tufa towers form under water in bubbles in
brine solution
– One of most productive ecosystems
– Water Diversion in Owens River
• Level dropped 46 feet since 1946.
– 1994 decision mandated rising lake 20 feet.
Mono Lake
Currently at
6382.3 ft.
Goal: 6391 ft.
in 2014
20th Century Low, January 1982
6,372 ft above sea level
Beginning of Diversions, 1941
6,417 ft above sea level
20th Century High, 1919
6,428 ft above sea level
Overflow Level, 100,000 years ago
7,200 ft above sea level
Aral Sea - disappearing
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Rivers being diverted for agriculture
From 4th to 8th largest lake
(1960) 68,000 km2; (1998) 28,000
Salinity increasing, salt blows onto
fields
Large losses
of water through
evaporation
Downstream
cropland and
estuaries are
deprived of
nutrient-rich silt
Flooded land
destroys forests
or cropland and
displaces people
Created Lakes:
Downstream
flooding is
reduced
Reservoirs
Provides water
for year-round
irrigation of
cropland
Reservoir is
useful for
recreation
and fishing
Can produce
cheap electricity
(hydropower)
Migration and
spawning of
some fish are
disrupted
Fig. 13.9, p. 301
• All have an estimated life span
until sediments fills them in.
• Block fish migrations, silt flow to
flood plain
• Control floods
• Clean Power source
Slide 10
Fig. 24.18, p. 653
Slide 25
Limnology: Study of lakes
• Littoral Zones:
– near shore, sunlight
– marsh, floating plants (macrophytes)
– Lots of decomposers – marsh food chain
• Limnetic Zone
– Open sunlight waters,
– main photosynthetic (producers) zone
• Profundal Zone
– Deep open water, too dark for photosynthesis
• Benthic Zone
– Bottom of lake inhabited by decomposers, and
other animals adapted to cold, oxygen poor
water: snails, worms, crayfish, catfish
Lake Ecosystem
Sunlight
Green
frog
Painted
turtle
Blue-winged
teal
Muskrat
Pond
snail
Littoral zone
Limnetic zone
Diving
beetle
Plankton
Profundal zone
Benthic zone
Yellow
perch
Bloodworms
Northern
pike
Fig. 7.14, p. 165
Dissolved Oxygen (DO)
• Oxygen needed for cell activity
• Low oxygen levels limit activity of
animals.
– Can cause massive die offs
• BOD- is biological oxygen demand
– caused by organic wastes in water
(pollution).
– Decomposers use up oxygen in the
rapid growth.
• DO Sensitive to temperature, pH
levels in water.
Types of
organisms
Clean Zone
Decomposition
Zone
Septic Zone
Normal clean water organisms
(Trout, perch, bass,
mayfly, stonefly)
Trash fish
(carp, gar,
Leeches)
Fish absent, fungi,
Sludge worms,
bacteria
(anaerobic)
Recovery Zone
Trash fish
(carp, gar,
Leeches)
8 ppm
Clean Zone
Normal clean water organisms
(Trout, perch, bass,
mayfly, stonefly)
8 ppm
Concentration
Dissolved oxygen
Oxygen sag
Biological oxygen
demand
2 ppm
Direction of flow
Point of waste or
heat discharge
Time of distance downstream
Fig. 19.3, p. 479
Slide 3
Seasonal changes in Alpine lakes
• Water mixes in Fall and Spring, oxygen,
nutrient levels uniform
• Summer warming stratifies lakes
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Water floats over cooler, forming a thermocline
Lower water is nutrient rich
Lack oxygen
Upper warmer water may run out of nutrient for
photosynthesis
• Winter may have insulating ice layer,
forming a stratification
Lake Succession
• Lakes fill-in over time. Nearly all the
nutrients come from outside the lake.
– e.g. Lake Yosemite filled valley after ice melted
• Oligotrophic few nutrients.
– Clear, bluish water little algae
– high dissolved oxygen
– Few fish, e.g.. Trout (small gills, easy to get
oxygen)
• Meso- intermediate
• Eutrophic- more and higher nutrient levels
– Low oxygen levels. Green color
• Senescent- filled in, becoming meadow
– Crane Flat in Yosemite
Age
Nutrients
Clarity
Color
Depth
Temperature
D Oxygen
D solids
Sediment
Locality
Fish
Oligotrophic
Young
Poor
Clear
Blue
Deep
Cold
High trough out
Low
Sparse, coarse
Mountains
Trout
Eutrophic
Old
Rich
Cloudy
Green to brown
Shallow
Warmer
Low, at surface
High
Deep, muddy
Valleys
Catfish
Eutrophic
Cultural
Eutrophication:
human influences
cause lakes to
become eutrophic due
to pollution, erosion.
Sunlight
Much shore
vegetation
High concentration
of nutrition and plankton
Limnetic zone
Wide
littoral
zone
Dense fish population
Gently sloping
shorelines
Salt, sand,
clay bottom
Eutrophic Lake
Fig. 7.15b, p. 166
Sunlight
Little shore
vegetation
Slide 18
Low concentration of
nutrition and plankton
Narrow
littoral
zone
Limnetic zone
Profundal zone
Sparce fish
population
Sand, gravel,
rock bottom
Oligotrophic Lake
Steeply
sloping
shorelines
Oligotrophic
Stream / River types:
(Indicated on topo maps)
• Permanent- year round
• Intermittent - seasonal, winter /
spring flow, dry summer fall.
• Interrupted- parts flow above ground,
other parts below (common in
Southern California)
• Slough - slower moving side channel
of larger creek, stream, river
Bends in the Rivers, Streams
• Coriolis affect causes water to flow in an
arch on a flat plain,
– to the right in the Northern hemisphere,
– causes streams to meander, as water curves
until it reaches an uphill.
– Can be seen in rivers in Central Valley
• As stream erodes the channel on its
outside bend, it deposits new sediments
on the inside. New soil is formed.
– Heavy rocks only moved in great floods, rivers
carry mostly gravel, sand, silt, and clay. Clay
moves the farthest.
• Meanders have a distinctive structure. On
the bend of a river, the water rushes to the
outside of a bend. This photograph shows
the inside, known as a slip-off slope. This
is a small area of deposition and creates a
gentle slope.
Rivers transport erosion debris
• Deforestation adds
to erosion, and
sediment loads in
rivers
• Add to near shore
pollution, nutrient
loads in oceans
Fig. 7.7, p. 157
Slide 8
Everglades
Kissimmee
River
Channelized
(
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Unchannelized
FLORIDA
(
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Lake
Okeechobee
West
Palm
Beach
Fort Myers
GULF OF
MEXICO
Naples
Fort
Lauderdale
Agricultural area
Treatment marsh
Water
conservation area
Canal
Miami
Everglades
National
Park
ATLANTIC
OCEAN
FLORIDA
Key Largo
Florida Bay
Area of
detail
20
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20
40
40
60 miles
60 kilometers
• Fifty miles (80 km) wide in
places, one to three feet (0.3 to
0.9 meters) deep in the
slough's center but only 6
inches (15 cm) deep
elsewhere, it flowed south 100
feet (30 meters) per day
• Water diversion started killing
off this vast marsh lands
• Largest restoration project
ever attempted started in 1996.
• National Parks are not islandsthey still can be influenced by
development outside their
boundaries.
Fig. 24.16, p. 651
Slide 23
Water Diversion
in California
• “Water wars”
– North- most of water
– South most of the
population
• Agriculture uses the
most
• Cities cut back the most
in droughts
• Population continues to
grow
• Recycling water can
save millions of gallons
• Wildlife loose out down
stream