Water Quality and Human Impact

Water Quality

Water Quality Factors

• Dissolved Oxygen

• Nitrates and Phosphates

• Turbidity

• pH

• Temperature

• ​Bio-indicators

Dissolved Oxygen

• amount of oxygen dissolved in the water.

• colder water usually has more oxygen.

• when fertilizers and nutrients get in the water, this increases plant grow. This will decrease the amount of oxygen in the water.

• all living things need oxygen to live.

Multiple Choice

What is dissolved oxygen?

• the amount of oxygen on land

• the amount of oxygen dissolved in water

Multiple Select

What can decrease the amount of oxygen in the water?

• Hotter water

• Increased plant growth

• Colder water

Nitrates

• Nitrogen is found in soil and is essential for plants to grow.

• Nitrogen can come from over-fertilized croplands, animal waste, and sewage.

• Too much nitrogen can cause an increase in algae growth.

• We know that this leads to less oxygen.

Multiple Choice

Is too much nitrogen good or bad?

• Good

• Bad

Multiple Select

What can cause too many nitrates getting in the water?

• fertilizers

• sewage

• plants

Turbidity

• Turbidity is the amount of dirt "hanging" in the water.

• If the water is too dirty, there may not be enough light to support plant growth.

• Plant roots help to hold on to the soil and prevent erosion.

• If trees are cut down, there is a greater chance of erosion.

Multiple Choice

What is turbidity?

• the amount of dirt in the water.

• the salt in the water

• the nitrogen in the water

Multiple Choice

Higher turbidity has more or less dirt in the water.

• more

• less

pH

• pH is a measure of the acidity of a solution.

• pH scale ranges from 0-14.

• 0-6 is acidic; 8-14 is basic.

• 7 is neutral and most organisms can only tolerate a pH close to 7.

• Acid rain entering the water can decrease the pH of a stream.

• If the stream becomes too acidic, fish will not be able to survive.

Multiple Choice

pH is the measure of...

• the acidity of a solution

• amount of salt in the water

• amount of dirt of water

Multiple Choice

A pH between 0-6 is considered...

• basic

• acidic

Salinity

• the amount of salt in the water

• more rainwater --> more freshwater

• in a bay (Chesapeake Bay), the salinity is lower near where the rivers enter the bay.

• the salinity is higher near where the ocean water enters.

Multiple Choice

Salinity is...

• the amount of salt in the water

• the amount of dirt in the water

Multiple Choice

The amount of salt in a bay increases the closer you get to...

• the rivers

• the ocean