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Inland Seas, Lakes, Rivers. Inland Waters. Fresh Water a precious resource ... animals adapted to cold, oxygen poor water: snails, worms, crayfish, catfish ... – PowerPoint PPT presentation

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Title: This week:


1
This week
  • Inland seas
  • Homework 2
  • Wednesday UC Botanical Garden
  • Next Monday Exam 2 includes
  • History of Conservation
  • Animal groups
  • Geology
  • Central Valley, Riparian
  • Inland Seas, Lakes, Rivers

2
Inland Waters
3
Fresh Water a precious resource
4
Importance of Fresh Water areas
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

6
River Zones
7
Our Watershed
  • Drains to Carquinez Straits

8
Lakes - water collects in a catch depression
  • Lake type determine by how it formed
  • Glacial
  • Tectonic
  • Landslide
  • Volcanic
  • Fluviatile
  • Shoreline
  • Terminal or Closed basin

9
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

10
Tarn
11
Cirque
12
Pater Noster
13
Kettle
14
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

15
Lake Tahoe
16
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

17
Crater Lake
18
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.

19
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.

20
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21
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.
  • Well see a small lake at Salmon Creek beach

22
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.

23
Mono Lake Currently at 6382.3 ft.Goal 6391 ft.
in 2014
24
Aral Sea - disappearing
  • Rivers being diverted for agriculture
  • From 4th to 8th largest lake
  • (1960) 68,000 km2 (1998) 28,000
  • Salinity increasing, salt blows onto fields



25
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26
Created Lakes Reservoirs
  • All have an estimated life span until sediments
    fills them in.
  • Block fish migrations, silt flow to flood plain
  • Control floods
  • Clean Power source

27
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

28
Lake Ecosystem
29
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.

30
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31
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32
Seasonal changes in Alpine lakes
  • Water mixes in Fall and Spring, oxygen, nutrient
    levels uniform
  • Summer warming stratifies lakes
  • 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

33
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34
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

35
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36
Eutrophic
Cultural Eutrophication human influences cause
lakes to become eutrophic due to pollution,
erosion.
Oligotrophic
37
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

38
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.

39
  • 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.

40
Rivers transport erosion debris
  • Deforestation adds to erosion, and sediment loads
    in rivers
  • Add to near shore pollution, nutrient loads in
    oceans

41
Everglades
  • 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 islands- they still can be
    influenced by development outside their
    boundaries.

42
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
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