Envirothon - Aquatics

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22 Φεβ 2014 (πριν από 3 χρόνια και 7 μήνες)

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January 2011

Outline


Overview of the water cycle


Chemical/Physical Properties


Water Sampling


Macro invertebrates


Watershed


Conservation/Pollution


Stream buffers


Wetlands & Aquifers


WATER CYCLE


Water covers 70% of the earth’s surface.








Water is a renewable substance


it is continuously
being recycled.


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WATER CYCLE

4

Hydrologic cycle:
Continual movement of water from
the atmosphere to Earth's surface through precipitation
and back to the atmosphere through evaporation and
transpiration.

CHEMICAL PROPERTIES OF WATER


Two hydrogen atoms attached to one oxygen atom


The chemical structure of water provides it with some
very unique properties.




H
2
O



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CHEMICAL PROPERTIES OF WATER


Water is a very stable compound


it is difficult to
break it apart into its component.


100˚C


boils and evaporates


0˚C


freezes and expands


4˚C


waters density is at its highest


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PHYSICAL PROPERTIES OF WATER

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Specific heat


pH


Conductivity


Universal Solvent


it can dissolve a large number of
different chemicals (
salinity, nitrates, phosphates
, etc.
We test freshwater streams to determine levels of
these solutes. They help us determine whether or not
a stream has good water quality.



PHYSICAL PROPERTIES OF WATER

NITRATES

8

PHYSICAL PROPERTIES OF WATER

PHOSPHATES



9

PHYSICAL PROPERTIES OF WATER

SALINITY



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PHYSICAL PROPERTIES OF WATER

TEMPERATURE


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PHYSICAL PROPERTIES OF WATER

Dissolved Oxygen (mg/L)

0
-
2 mg/L:

not enough oxygen to support life

2
-
4 mg/L:

only a few kinds of fish and insects can
survive

4
-
7 mg/L:

acceptable for warm water fish

7
-
11 mg/L:

very good for most stream fish including cold
water fish

Percent Saturation (%)

Below 60%:

poor; water too warm or bacteria using up
DO

60
-
79%:

acceptable for most aquatic organisms

80
-
100%:

excellent for most aquatic organisms

112% or more:

too high, may be dangerous to fish

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Water Sampling

SEDIMENTATION


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Humphreys Brook, Summer 2009

Breached Sediment Fence

Water Sampling

E. COLI


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MACRO
-
INVERTEBRATES


Indicator of aquatic life (biodiversity)


They are a link in the food chain


They are sensitive to pollution


Macro
-
invertebrates can be used as indicators of water
quality.





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MACRO
-
INVERTEBRATES

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Watershed Boundary

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Tidal Bore

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The
Petitcodiac

River was once known for its tidal
bore being the highest in North America, over two
meters



Water Conservation Methods


Three areas to conserve water: Household,
Commercial, and Agricultural


For household: Low
-
flush toilets, high
-
efficiency clothes
washers.


For Commercial: Reclamation systems (
ie
. Car washes),
waterless urinals, steam sterilizers.


For Agricultural: Overhead irrigation, or, a more
expensive but successful measure, drip irrigation.

Point & Non
-
Point Pollution


Point
Polution
: where wastewater/contaminants enter
a waterway through discrete means,
ie
. Ditch or pipe.


Sewage treatment plants, factories, storm drains, etc.



Non
-
Point
Polution
: where wastewater/contaminants
enter a waterway through a larger in
-
discrete means,
ie
. Agricultural field, urban runoff.


Parking lots/roads/highways, agriculture, etc.

STREAM BUFFERS

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Prevents erosion of banks


Provides shade to the stream (temperature control)


Filters pollution from entering the stream


Supplies shelter and food to aquatic animals


Easy way to improve water quality

STREAM BUFFERS

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WETLANDS

23


Natural buffers


Acts as a sponge during large storms


Naturally filters water


Sustains more life than any other ecosystems


Canada has 14% of wetlands of the world


65% of coastal wetland in Atlantic Canada have been
damaged through agriculture and urban
development.

Types of Aquifers


Unconfined and Confined


Freshwater Distribution


Canada: We have 7% of the worlds’ freshwater.

Water: A Finite Resource


Rate of water consumption overcomes the rate of
renewal


Statistics Canada has determined freshwater in
Canada has been in decline for the last 30 years


90% of this lost freshwater has gone towards economic
activity, only 9% has gone towards residential us



Hydraulic Fracturing




fracking
” process that results
in the creation of fractures in rocks.

Impact on Aquatic Ecosystems


The
Petitcodiac

Causeway


10 million cubic meters of silt


Restricted movement of fish


Reduced the region’s salmon catches by 100%


Biomass Harvesting


Reduced soil pH can result in acidifying water source(s)
nearby (
Pollett

River)


Difficulties with erosion control


Reduced shade/buffer zones for nearby
watersources