Water Chemistry Flashcards
1
Q
What are six things that influence water chemistry?
A
- Human influence; 2. Rain; 3. Parent material; 4. Biological interactions; 5. Chemical processes; 6. Evaporation
2
Q
Does freshwater chemistry vary greatly?
A
Yes
3
Q
These control primary production of aquatic ecosystems
A
Nutrients
4
Q
What are four things that water chemistry controls?
A
- Physiology; 2. Biogeochemistry; 3. Pollutant behavior; 4. Aquatic organism health
5
Q
The highest abundance of organisms is found in this range of the environmental gradient
A
Optimal range
6
Q
Organisms are rare in this zone of the environmental gradient
A
Zone of stress
7
Q
Organisms are absent in this zone of the environmental gradient
A
Zone of intolerance
8
Q
What are six types of materials transported in freshwater?
A
- Gases; 2. Dissolved nutrients; 3. Dissolved inorganic matter; 4. Suspended/dissolved organic matter; 5. Suspended/dissolved trace metals; 6. Suspended inorganic matter
9
Q
What are three gases that can be transported by freshwater?
A
N2, CO2, O2
10
Q
What are three dissolved nutrients that can be transported by freshwater?
A
Nitrogen, phosphorus, silicon
11
Q
What are seven types of dissolved organic matter that can be transported by freshwater?
A
Ca2+, Na+, Mg2+, K+, HCO3- (bicarbonate), SO4-2 (sulfate), Cl-
12
Q
What are four types of suspended/dissolved organic matter that can be transported by freshwater?
A
Leaves, soil, plants, organisms
13
Q
What are five examples of suspended inorganic matter that can be transported by freshwater?
A
Aluminum, iron, silicon, calcium, potassium
14
Q
These are tiny solid particles of dissolved substances found inside liquid water
A
Particulates
15
Q
Particulates can usually be removed from water using this
A
Mesh filter of a certain size
16
Q
What are three categories of particulates?
A
Dissolved, colloidal, gravitoidal
17
Q
This category of particulates never settles and causes turbidity
A
Colloidal
18
Q
Colloidal particulates bind with these
A
Dissolved substances
19
Q
This category of particulates eventually settles
A
Gravitoidal
20
Q
What are the three components of water quality?
A
Physical, chemical and biological
21
Q
This is a measure of natural hot/cold fluctuations
A
Temperature
22
Q
This is also known as the “abiotic master factor”
A
Temperature
23
Q
What are four sources of temperature changes?
A
- Sun; 2. Water inputs; 3. Heat exchanges; 4. Thermal pollution
24
Q
What are five factors that can change the temperature of water?
A
Color, depth, shade, location, time of year
25
How does increasing the temperature affect chemical reactions?
Increases rate of reactions
26
How does increasing the temperature affect chemical toxicity?
Increases toxicity
27
How does increasing the temperature affect dissolved oxygen?
Decreases dissolved oxygen
28
What are six ways temperature affects aquatic organisms?
1. Specific ranges; 2. Primary production; 3. Metabolic rates; 4. Spawning; 5. Temperature shock; 6. Immunoresponse
29
This is a measure of particulate matter and dissolved color
Turbidity
30
What are six sources of turbidity?
1. Erosion; 2. Increased nutrients; 3. Phytoplankton/algae; 4. Resuspended sediments from the bottom; 5. Waste discharge; 6. Urban runoff
31
What units are used to measure turbidity?
Nephelometric turbidity units (NTUs)
32
What are three devices used to measure turbidity?
Colorimter, Secchi disk, Secchi tube
33
What is the most accurate device used to measure turbidity?
Colorimeter
34
What device is used to measure turbidity in lakes or deep water?
Secchi disk
35
What device is used to measure turbidity in streams or shallow water?
Secchi tube
36
What is the acceptable turbidity level for cool water in Oklahoma?
10 NTUs
37
What is the acceptable turbidity level for lakes in Oklahoma?
25 NTUs
38
What is the acceptable turbidity level for surface water other than lakes in Oklahoma?
50 NTUs
39
What is the acceptable turbidity level for drinking water?
< 1 NTUs
40
Turbidity is important to these three aspects of freshwater
Aesthetic quality, water chemistry, aquatic life
41
What are two negative effects of turbidity on the aesthetic quality of water?
Reduced recreation and cost of treatment
42
What are two negative effects of turbidity on water chemistry?
Increased temperature and decreased oxygen
43
What are five fish habits/characteristics that are negatively affected by increased turbidity?
Spawning, gills, mate selection, migration, prey capture
44
What plant process is negatively affected by increased turbidity?
Photosynthesis
45
Is turbidity more of a concern in a lake or a stream?
Lake
46
What are five things that are negatively affected lack of light penetration caused by turbidity in lakes?
1. Photosynthetic organisms; 2. Dissolved oxygen; 3. Visual predators; 4. Angler success; 5. Aesthetics
47
In streams, this is the volume of water discharged or moving through a stream at any given time
Flow
48
What is the formula for stream discharge?
Area x velocity = discharge
49
What are two examples of units used to describe stream discharge by total volume?
Acre-ft and millions of gallons
50
What is an example of a unit used to describe the rate of stream discharge?
Cubic feet per second
51
What are four things that cause variation in stream discharge?
1. Precipitation amount; 2. Temporal changes; 3. Water withdrawals; 4. Watershed changes
52
What are three watershed changes that can impact stream flow?
Land management, physical changes (i.e. erosion), and dams
53
What is the first step in measuring stream flow?
Stretch a measuring tape across the "start" line
54
At what intervals should the depth of the water be measured to determine stream flow?
One-foot intervals
55
If a stream is wider than 20 feet, at what intervals should it be measured to determine stream flow?
Two-foot intervals
56
At what three points should the velocity and water depth at each interval be measured when determining stream flow?
"Start" line, midpoint, and "finish" line
57
An alternative way to measure stream flow is to measure the width of the stream and divide the cross section into these equal-width shapes
Rectangles
58
Another way to measure stream discharge is by measuring the elevation of the stream surface, also known as this
Stage
59
What are three objects that can be used as 'visual floats' to measure stream discharge?
Orange, rubber duck, half-filled water bottle
60
This is a measure of how well water can hold an electrical current
Specific conductance
61
Where do ions in the water come from?
Surrounding geology/groundwater
62
What are four reasons why conductivity is important in freshwater systems?
1. Indicates high/low nutrients; 2. Indicates salt-water pollution; 3. Brackish water is not suitable for many species; 4. Sampling gear (i.e. electrofishing) may be influenced
63
What are three sources of salt pollution?
Agriculture, desalination, road salt
64
These are inorganic salts and small organic matter in water
Total dissolved solids (TDS)
65
What are three sources of TDS?
Sedimentary rock weathering; freezing/thawing; mechanical weathering
66
What are three reasons why TDS are important in freshwater?
1. TDS are related to runoff; 2. TDS determine whether water is hard or soft; 3. Mollusks and crustaceans need calcium
67
What two minerals primarily determine whether water is hard or soft?
Calcium and magnesium
68
What are three reasons why water hardness is important?
1. Hardness indicates the ability of water to precipitate soap; 2. Hardness influences domestic water supply; 3. Deionized water is used in laboratories
69
What are four effects of hard water on domestic water supplies?
1. Scaling/soap interference; 2. Decreases water heater efficiency; 3. Vegetables lose flavor; 4. People buy water softeners to improve water taste
70
This type of water is used in laboratories and has no ions
Deionized water
71
When multiple water molecules exist, water can transfer these in the form of hydrogens
Protons
72
If a water molecule gains a proton (H+), it becomes this
Hydronium ion (H3O+)
73
If a water molecule loses a proton (H+), it becomes this
Hydroxide ion (OH-)
74
In pure water, the concentrations of these two ions are equal
Hydronium (H3O+) and hydroxide (OH-)
75
Which ion in water is acidic, hydronium or hydroxide?
Hydronium
76
Which ion in water is basic, hydronium or hydroxide?
Hydroxide
77
By how much hydrogen ion concentration does each step in the pH scale increase?
10x
78
What is the pH scale calculated as?
-log10[H+]
79
What is a typical pH range for surface freshwater?
6 - 9
80
Swamps can have a pH as low as this
4.3
81
What is a typical pH range for saltwater?
7.7 - 8.1
82
What pH range do most organisms prefer?
5.5 - 9.5
83
What are five things that can change pH in water?
1. Rocks/minerals; 2. Chemical interactions; 3. Rain; 4. Carbon dioxide; 5. Photosynthesis
84
Does an increase in carbon dioxide raise or lower pH in the water?
Lower
85
Does an increase in photosynthesis raise or lower pH in the water?
Raise
86
What are four reasons why pH is important in water?
1. Acids release heavy metals; 2. The toxicity of some heavy metals increases; 3. Extreme pH increases solubility of some chemicals; 4. Wildlife have specific pH ranges
87
At what time of day is water pH lowest?
In the morning (~7 am)
88
At what time of day is water pH the highest?
Late afternoon/early evening (~5 pm)
89
What are three ways to measure pH?
pH meter, Sonde, testing kits
90
What are two common types of pH testing kits?
Litmus paper and titration
91
This lake in Tanzania is an example of an environment with extreme pH (as high as 10.5)
Lake Natron
92
This is the capacity of water to react with strong acids or bases
Alkalinity
93
Alkalinity is the measure of water's ability to do this
Neutralize acids
94
What are two ions that lower the pH of water?
Carbon dioxide (CO2) and c9arbonic acid (H2CO3)
95
What are three ions that raise the pH of water?
Hydroxide ions (OH-), carbonates (CO3-), and bicarbonates (HCO3-)
96
This is a solution that contains both an acid and a base and is able to mitigate changes in pH
Buffer
97
What kind of acid do buffers contain?
Weak acid (HA)
98
Whether you add acid or base to a buffer, you end up with either of these two compounds
HA or BA
99
What are two substances commonly found in acid rain?
Sulfur dioxide (SO2) or nitrogen oxide (NO)
100
What are two sources of chemicals that cause acid rain?
Industrial processes and fossil fuels
101
Sulfur dioxide and nitrogen oxide combine with water to form these two acids that make up acid rain
Sulfuric acid and nitric acid
102
During mining, this compound can be exposed to oxygen
Pyrite (FeS2)
103
Oxygen + pyrite + water = ?
Sulfuric acid
104
Sulfuric acid from mines dissolves away rocks and leaches metals, leading to this process
Acid mine drainage
105
When acidic water drains out of mines and into streams, the metals in it react with this to turn the water a bright color
Oxygen
106
This is considered to be the second most important abiotic factor in aquatics
Dissolved oxygen
107
What are three sources of dissolved oxygen?
Photosynthesis, diffusion from air, aeration/wind
108
Dissolved oxygen impacts this process, usually at the bottom of a body of water
Decomposition
109
Can dissolved oxygen exceed 100% saturation?
Yes
110
These form when there is a lack of oxygen in a particular area of the water
Hypoxic zones
111
What are three characteristics of hypoxic zones?
Warm temperatures, excess nutrients, and low oxygen
112
What are three ways that fish can be affected by lack of dissolved oxygen
Metabolism, behavior, body size
113
What are two ways to measure dissolved oxygen?
Sonde and titration
114
This is the amount of oxygen needed to break down organic matter
Biological oxygen demand (BOD)
115
Over what time period does BOD measure oxygen consumed?
5 years
116
What does BOD stand for?
Biological oxygen demand
117
At what time of day is dissolved oxygen in the water highest?
Dusk
118
What are the three main processes involved in photosynthesis?
Splitting water, capturing light, fixing carbon
119
Are only oxygen and carbon dioxide required for photosynthesis?
No
120
What are the two most limiting elements for photosynthesis in aquatics?
Nitrogen and phosphorous
121
This element is one of the largest requirements for aquatic photosynthesis and is found in DNA
Nitrogen
122
This element is the second largest requirement for aquatic photosynthesis and is found in ATP
Phosphorous
123
What are the six forms of nitrogen important to aquatics?
1. Nitrogen gas (N2); 2. Ammonia (NH3); 3. Ammonium (NH4+); 4. Nitrite (NO2-); 5. Nitrate (NO3-); 6. Organic nitrogen
124
What is the preferred form of nitrogen for plants?
Nitrate (NO3-)
125
What are three important processes in the nitrogen cycle?
Nitrogen fixation, nitrification, denitrification
126
What are four sources of nitrogen in aquatics?
Soil, organism waste, decaying organic matter, fertilizers
127
What are the two forms of phosphorous found in aquatics?
Inorganic and organic phosphorous
128
This form of phosphorous can be dissolved or particulate and usually makes up less than 5% of the total phosphorous in a lake
Inorganic phosphorous (PO4 3-)
129
What is a normal range of total phosphorous?
< 10 ug/L - > 200 ug/L
130
What is the main source of aquatic phosphorous?
Rocks/minerals
131
After being weathered by water from rocks/minerals, phosphorous binds to these in the water
Organic compounds
132
This is when molecules adhere to the surface of a material
Adsorption
133
This is when molecules are drawn into a material
Absorption
134
Limnologists are often interested in this aspect of a body of water
Primary productivity
135
This is the rate at which primary producers create organic material
Primary productivity
136
Primary productivity relies on these
Nutrients
137
Whichever nutrient prevents growth is known as this
Limiting nutrient
138
What is the Redfield Ratio for stream algae to do photosynthesis?
160:16:1 for C:N:P
139
A system's photosynthesis is considered nitrogen-limited if its nitrogen is at what number in the ratio?
<15
140
A system's photosynthesis is considered phosphorous-limited if its phosphorous is at what number in the ratio?
>30
141
An excess of nutrients leads immediately to this
Increase in primary producer population (algae bloom)
142
If there are not enough consumers to limit primary productivity in a system with excess nutrients, this process will occur
Eutrophication
143
This type of system has low levels of organic matter
Oligotrophic
144
This type of system has moderate levels of organic matter
Mesotrophic
145
This type of system has high levels of organic matter
Eutrophic
146
What is the limiting nutrient in oligotrophic systems?
Phosphorous
147
Are oligotrophic systems usually deep and clear or shallow and murky?
Deep and clear
148
Which nutrient classification can fill in and become shallower?
Eutrophic
149
Which nutrient classification can have an abundance of plants?
Eutrophic
150
Which nutrient classification has excessive nutrient ratios?
Eutrophic
151
What does HAB stand for?
Harmful algae bloom
152
Are HABs more common in lakes or streams?
Lakes
153
Why are HABs less common in streams?
Moving water does not allow nutrients to build up as much as in lakes
154
What are four ways nutrients can be measured in aquatics?
Sonde/probe, testing kit, colorimeter, nutrient analyzers
155
What are six common pharmaceuticals found in water?
Pain medications, antibiotics, antidepressants, hormones, caffeine, recreational drugs
156
How many drugs can be removed from wastewater treatment?
9 out of 118
157
What are three suspected sources of hormones that have caused male fish to have impaired sperm and produce egg cells?
Birth control pills, Bisphenol A, Atrazine
158
This substance has been found in freshwater eels, making them hyperactive and increasing cortisol
Cocaine
