1	Physical Assessment Chapter 8
2	Physical Assessment Physical conditions of a stream influence what lives in the stream. Done at your own monitoring plans frequency. Helpful if done with Chemical Assessment. Parameters measured at the transect.
3	Weather Long term weather conditions greatly affect our streams. Cloudy weather can lower dissolved oxygen by lowering plant productivity. Rain may lower some pollution levels because of dilution. Rain may raise some pollution effects because of increased surface run-off. Wind may increase the dissolved oxygen level.
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6	Water Color May provide an immediate clue to a stream’s health. Clear water does not always equal clean water. Some colors you may see: Brown- usually due to sediment Green- indicates high algae levels Oily Sheen- can indicate a petroleum or chemical spill Reddish- or orange color, usually means iron oxides are present Blackish- usually caused by natural leaf decay in fall Chalky- can be caused by salts and detergents in water
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9	"Dark water color due to..." Dark water color due to leaf decay
10	Water Odor May provide and immediate clue to a stream’s health. Manure or Sewage- indicates an urban or animal waste pollution Rotten egg- caused by hydrogen sulfide gas released during anaerobic decomposition (organics breaking down without oxygen. Petroleum- chemical smells indicate a direct pollution source For Lakes additional category of Fishy
11	Stream Width and Depth Stream Width The distance from waters edge to waters edge. Measured in meters in the same location each time. Stream Depth Important to fish for over- wintering and feeding areas. Measured in meters along transect in one meter intervals.
12	"These two measurements create a..." These two measurements create a cross-sectional area which is used to calculate flow. [(D+D+D)n]xW=A D= depth n= number of depth measurements W= width A= Cross sectional area [(0.75+1.5+0.75)/3]x1.5=1.5m²
13	Stream Velocity and Flow Velocity - how fast the stream is flowing Flow - how much water is moving through the stream Also called discharge. Calculated by multiplying velocity by the cross-sectional area V x A= D Is important when looking at the effects of other parameters.
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15	Water Temperature Many characteristics of the stream are affected by water temperature Some species require certain temperature ranges Water temperature can fluctuate widely Thermal pollution - where humans change the natural water temperature adversely affecting stream life Releasing heated cooling water from industry or heated run- off Removing the riparian zone
16	Transparency Measure of water clarity Affected by the suspended materials in the water. Soil, algae, plankton, microbes Affects other water quality parameters. Increased suspended materials leads to increase water temperature. Chemicals can attach themselves to suspended materials. When materials settle out they can clog gills, destroy habitat, reduce food, and smother eggs.
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20	132 Lake Sites, 2000-2001, Secchi Depth