Aquatics Teacher Packet

AQUATICS BENCHMARK ASSESSMENTTeacher Answer Packet

1. Use the diagram of the water cycle below to answer the following questions.

a. How is freshwater replenished on earth?

precipitation

b. What is the term for the underground

supply of freshwater?

aquifer

2. Refer to the pie chart below on water consumption. Identify 5 ways you can reduce your personal water consumption.

a. _Use low-flow showerheads

b. _Use low-flush toilets

c. _Take shorter showers

d. _Only run dishwasher and washing machine when loads are full

e. _Turn off the faucet while brushing teeth

3. Complete the table below on the salinity of water bodies.

Salinity / Type of Water

Description Example of Aquatic Environment

Fresh Contains no salt or very little saltSalinity ranges from 0 – 1 ppt

River, Lake, Stream, etc.

Brackish A mixture of salt and freshwaterSalinity ranges from 2 – 17 ppt

Estuary

SaltWater has a salt concentration over 17 pptAverage salinity of ocean is 35 ppt

Ocean

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Aquatics Teacher Packet4. Complete the chart for acceptable water quality levels.

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INDICATOR ACCEPTABLE LEVELpH 6.5 – 8.5DO 5 – 8.5 ppmCO2 < 25 ppm

Nitrates <0.3 ppmPhosphates <0.015 ppmHardness 0-60 ppm (soft), 120-180 ppm

(hard)Mayflies presentStoneflies present

Caddisflies presentColiform absent

Aquatics Teacher Packet5. Biological and chemical water quality data were collected from 4 sites in the

Bear Creek watershed. The majority of the land in the rural Bear Creek watershed is inhabited, but there is also a fish farm (farm where fish are raised), a mining company, and a dairy farm. Analyze the water quality data.

WATER QUALITY DATAWater temp (°C)

# of Mayflies

# of Stoneflie

s

# of Caddisflies pH Hardness

(ppm)Nitrates(ppm)

Phosphates(ppm)

DO (ppm)

Coliform

Site A 24 6 2 5 6.1 55.0 7.0 3.2 1.9 PresentSite B 24 293 156 248 7.2 102.0 1.7 0.5 2.9 AbsentSite C 15 1571 24 1391 7.2 98.5 0.25 0.0 7.3 AbsentSite D 15 1558 613 1354 7.2 114.0 0.25 0.01 7.4 Absent

a. Which site has the worst water quality? Explain.Site A has the worst water quality. The populations of macroinvertebrates are very low. The pH is below the acceptable range, and is too acidic. Water hardness is low, indicating a lack of limestone as a geologic substrate. Both nitrates and phosphates are elevated. Dissolved oxygen is too low for organisms to survive. The presence of coliform indicates the body of water is contaminated with animal waste.

b. Which site has best water quality? Explain.Site C has the best water quality. It has the most macroinvertebrates. In addition, all chemical tests are in the acceptable range. The absence of coliform indicates no pollution from animal waste.

c. Rank all four sites in order from best to worst water quality.

Site C Site D Site B Site A

d. Describe the relationship between water temperature and the amount of dissolved oxygen. As water temperature decreases, the amount of dissolved oxygen increases.

e. Which site is most affected by eutrophication? Explain.Site A is most affected by eutrophication. Site A has the highest levels of nitrates and phosphates. In addition, the low dissolved oxygen level is indicative of eutrophication.

f. Which site is most affected by acid rain? Explain.Site A is most affected by acid rain. It has the most acidic pH and the lowest water hardness. This indicates little limestone in the soil to buffer against the effects of acid rain.

g. Which site is contaminated with animal waste? Explain.Site A is contaminated with animal waste. The presence of coliform bacteria indicates pollution by animal waste.

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Aquatics Teacher Packet6. Identify the name of the macroinvertebrate under each image.

__mayfly__ __damselfly__ __stonefly__

__hellgrammite___ __aquatic worm__ __caddisfly__

7. Several different types of stoneflies, mayflies, and caddisflies indicate healthy water quality.

a. Rank these three indicator organisms from most tolerant of pollution to least tolerant of pollution.

Most tolerant of pollution: __caddisflies

__mayflies

Least tolerant of pollution: __stoneflies

b. Which of these three indicator organism would disappear first in a polluted aquatic ecosystem?

__stoneflies

c. What water conditions would be best for the survival of macroinvertebrates?fast-moving stream because it oxygenates the water

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Watershed:

The total land area from which water drains into a particular water body

A

B

C

D

Aquatics Teacher Packet8. Define a watershed.

9. Refer to the map of the Chesapeake Bay and its major tributaries. On the map, add a: Label A—River that adds the majority of the freshwater to the Bay Label B—Area with the highest salinity Label C—Area with the lowest salinity Label D—Area with greatest tidal changes

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Aquatics Teacher Packet

10.Label the diagram of fish with the parts of its anatomy.

11.Identify the fish below and fill in the important information about each fish.

Common Name

_______Channel Catfish____________

Body Shape: ___Torpedo________ Mouth Position: __Wide, upturned____

Caudal Fin: ____Forked_________ Dorsal Fins: _____Two (with rays)____

Pectoral Fins: __Present________ Pelvic Fins: ______Present__________

Other fins: ____Anal fin_________ Lateral line: ______Visible________

12.Answer the following questions about aquatic vegetation.

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Spiny dorsal finSoft dorsal fin

Operculum (gill cover)

Caudal (tail) fin

Pectoral fin

Mouth

Aquatics Teacher Packet

a. What do these terms stand for?

o SAV – Submerged Aquatic Vegetation

c. What two water factors affect the growth of SAV in the Chesapeake Bay?

Salinity and Turbidity

d. Explain how the presence of SAV would help the fish in the cartoon and other aquatic animals in the bay

The presence of SAV is very important to the bay. Among its many benefits, SAV providehabitat, shelter, food, and oxygen to the bay. In addition, SAV help maintain water quality and protect shorelines from erosion.

e. Explain two causes that have lead to the decline of SAV in the Chesapeake Bay

SAV has declined in the bay due to eutrophication and sedimentation. Both of these causes reduce the amount of sunlight available to SAV. Over-enrichment of nutrients causes algae blooms which prevent sunlight from reaching SAV. Too much sediment increases the total dissolved solids in the bay. This also reduces the light available for the SAV.

13.Using the graphic below, explain what occurs during primary, secondary, and tertiary treatment.

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Primary Secondary TertiaryWASTE WATER TREATMENT DIAGRAM

Aquatics Teacher Packet

Step in Wastewater Treatment

Explanation

Primary

Wastewater goes through screens to remove coarse debris and grit chambers. Wastewater is then funneled into large sedimentation tanks and left undisturbed to allow heavy particles to settle out. This sludge moves onto sludge treatment while the remaining wastewater moves onto secondary treatment.

Secondary

In an aeration tank, oxygen is added to encourage the growth of microorganisms that consume the organic matter. Water then flows into another sedimentation tank, where sludge settles out and moves onto sludge treatment. The remaining wastewater goes through disinfection or chlorination before moving onto tertiary treatment.

Tertiary/ AdvancedMany salts, pesticides, phosphates, and other pollutants remain after secondary treatment. Tertiary treatment removes these materials and releases a treated effluent that is theoretically “potable.”

14.Circle the best answer. Correct answers are bolded, underlined, and italicized

Which law regulates what is discharged from a wastewater treatment plant?(Clean Water Act, Safe Drinking Water Act)

Which law makes water potable?(Clean Water Act, Safe Drinking Water Act)

What classification of pollution comes from a wastewater treatment plant? (nonpoint pollution, point pollution)

What type(s) of pollution results from the process of wastewater treatment?(acid rain, eutrophication, thermal pollution)

15.Use the graphic to complete both charts.

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Aquatics Teacher Packet

Pollution source Point or Nonpoint

Farm Nonpoint

Houses Point

Boat Point or Nonpoint depending upon the situation

Factory Point

Factory’s parking lot Nonpoint

Type of pollution produced Pollution source

Acid rain Factory releases SO2 and NOBoat releases NO

Eutrophication Runoff from the farm and fertilizer on lawns

Thermal pollution Factory pulls in water as a coolant and releases warmer water

16.Fill in the blanks.

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Aquatics Teacher Packet ___Nitrates__ and __phosphates__ are the two nutrients that cause eutrophication. Because of the

excess nutrients ___algae___ grows rapidly. Decomposers then move in and break down all

organic matter. This results in low levels of oxygen which can create __dead__ ___zones___.

Thermal pollution increases the ___temperature___ of the water. This change results in lower

levels of __dissolved oxygen_ in the water.

Acid rain ___lowers____ the pH of a body of water. It is primarily caused by sulfur dioxide and

nitrogen dioxide created by the burning of fossil fuels.

17.Below is an energy pyramid illustrating biomagnification.

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Aquatics Teacher Packet

Why are there more dots in the higher trophic levels?

The concentration of pollutants increases as it moves up the food chain.

Why are heavy metals such as mercury harmful?

They have high mobility, are fat soluble, and are biologically active.

In what part of an organism does the pollutant accumulate?

Fats

The organism at the highest trophic level is not killed by this pollutant; instead it can have damaging effects on its offspring. Explain.

Biomagnification of the pollutant interferes with the reproductive system of the organism. For example, biomagnification of DDT resulted in bald eagles laying eggs with shells that were too thin.

18.Check all that apply to each aquatic environment.

Aquatic environment

Salt water

Fresh water

Tidal Nesting ground

Light penetrates almost to bottom

Estuary √ √ √ √

Wetland √ √ √ √

Streams √ √

Ocean √ √

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