Title: This week:
1This 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
2Inland Waters
3Fresh Water a precious resource
4Importance of Fresh Water areas
5Fresh 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
6River Zones
7Our Watershed
- Drains to Carquinez Straits
8Lakes - water collects in a catch depression
- Lake type determine by how it formed
- Glacial
- Tectonic
- Landslide
- Volcanic
- Fluviatile
- Shoreline
- Terminal or Closed basin
9Glacial 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
10Tarn
11Cirque
12Pater Noster
13Kettle
14Tectonic 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
15Lake Tahoe
16Volcanic 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
17Crater Lake
18Landslide 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.
19Fluviatile - 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.
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21Shoreline -
- 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
22Terminal 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.
23Mono Lake Currently at 6382.3 ft.Goal 6391 ft.
in 2014
24Aral 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
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26Created 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
27Limnology 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
28Lake Ecosystem
29Dissolved 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.
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32Seasonal 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
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34Lake 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
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36Eutrophic
Cultural Eutrophication human influences cause
lakes to become eutrophic due to pollution,
erosion.
Oligotrophic
37Stream / 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
38Bends 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.
40Rivers transport erosion debris
- Deforestation adds to erosion, and sediment loads
in rivers - Add to near shore pollution, nutrient loads in
oceans
41Everglades
- 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.
42Water 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