Test #2 Flashcards
1
Q
5 inputs of CO2 to water
A
- rain (picked up from air)
- water trickling through organic soil
- subterranean water
- respiration of organisms
- decomposition at the bottom of the lake
2
Q
Which isotope of Carbon is common?
A
12C
3
Q
What percent of carbon content is 12C?
A
98.9%
4
Q
Which isotope of Carbon is rare?
A
13C
5
Q
Which isotope of Carbon is rare and radioactive?
A
14C
6
Q
Which isotope of Carbon do photosynthesizers preferentially pick up?
A
12C
7
Q
Which isotope of carbon do anaerobic metabolizers preferentially pick up?
A
13C
8
Q
Where and how is C14 formed?
A
high altitudes by cosmic radiation
9
Q
What is pH an abbreviation for?
A
power of hydrogen
10
Q
What is the equation for the small fraction of water dissociating?
A
H20 <> H+ + OH -
11
Q
When does H+ = OH-
A
in pure water
12
Q
What is the pH and temperature of neutral water?
A
7, 24 degrees C
13
Q
negative of the base 10 logarithm of the H+ ion
A
pH
14
Q
pH equation
A
-log [H+]
15
Q
What is H+ called?
A
hydrogen ions or protons
16
Q
What is the range of pH?
A
0-14
17
Q
What is a neutral pH?
A
7
18
Q
pH <7
A
acid (acidic)
19
Q
pH >7
A
base (alkaline)
20
Q
What is the pH of most waterways?
A
6-9
21
Q
What multiplier does acidity go by from neutral (7)
A
x10
22
Q
2 indicators of changing pH
A
- color change
- electrodes
23
Q
What does CO2 dissolve in natural waters as?
A
carbonic acid (H2CO3)
24
Q
Equation for carbonic acid dissociating bicarbonate and hydrogen ions
A
H2CO3 > HCO3- + H+
25
pH of rain water
5.6
26
what does the pH of water come from?
CO2 picked up in the atmosphere
27
what extra thing can rain pick up extra hydrogen ions from
pollution
28
What phenomenon happens when rain water picks up extra hydrogen ions?
acid rain
29
What does acid rain cause?
fish mortality
30
What causes pollution from industry burning fossil fuels?
human activity
31
Equation for sulfurous acid
SO2 + H2O > H2SO4
32
Equation for nitrous acid
NO2 + OH- > HNO3
33
What produces sulfur dioxide?
volcanoes
34
Equation for carbonic acid producing H+
H2CO3 <> HCO3- + H+
35
Equation for sulfuring acid producing H+
HSO3 + H+
36
What does edaphic mean?
from the soil
37
What is strip mining?
surface mining of coal
38
What does strip mining contain large amounts of?
pyrite
39
Chemical formula of pyrite
FeS2
40
What happens to pyrite in an edaphic environment?
oxidized to H2SO4
41
What is H2SO4
sulfuric acid
42
What does sulfuric acid do to rivers and streams?
causes them to acidify
43
What is true of edaphic volcanic lakes?
very low pH due to sulfur
44
How extreme can the pH of volcanic lakes be?
2
45
What is the 2nd thing that can happen to volcanic lakes?
high pH due to sodium carbonate (=soda lakes)
46
How extreme can the high pH of volcanic lakes be?
9-12
47
Sodium carbonate dissociation equation?
Na2CO3 > Na+ + NaCO3-
48
What can sodium carbonate soak up?
H+
49
What is sodium carbonate used in?
glass manufacturing
50
What do edaphic anaerobic sediments at the bottom of lakes have?
bacteria producing H2S
51
What does H2S smell like?
rotten eggs
52
What does H2S lead to?
H2SO4 <> HSO3+ + H+
53
What do edaphic soil particles blown in the wind have?
dust containing calcareous particles
54
What does calcareous mean?
calcium based
55
What do calcareous particles do?
neutralize acid rain
56
What do prairies naturally have more of?
dust
57
What does it mean that prairies have more dust?
their waterways have less problems with acid rain
58
How does acidity affect oligotrophic or dystrophic lakes?
decomposition is inhibited
59
What is the relationship between CO2 and acid salts?
half-bound to form
60
What are the acid salts in water?
bicarbonates (X(HCO3)2)
61
What is the relationship between CO2 and neutral salts?
bound to form
62
What are the neutral salts in water?
carbonates (XCO3)
63
What is the free dissolved gas in water?
CO2
64
What does photosynthesis do in water?
removes the free CO2
65
What does photosynthesis removing the free CO2 do to the water?
raises pH
66
What does respiration do?
adds free CO2
67
What does free CO2 do to the water?
lowers pH
68
What are buffers?
solutions that resist change in hydrogen ion concentration when an acid or base is added
69
What is alkalinity?
buffering system of water
70
What do carbonic acid and its resulting salts do in water?
act as a buffer
71
What do well buffered lakes do?
resist change in pH
72
What are vernal pools?
temporary wetland filled with snowmelt or rain
73
Are vernal pools well buffered?
no
74
What does it mean that vernal pools are not well buffered?
acid rain can cause big fluctuations in pH and make them unsuitable for amphibians
75
Where are diel changes in alkalinity negligible?
dilute waters
76
Where have small pools been seen to have huge diel swings in pH?
the desert
77
What specific location has been seen to have huge diel swings in pH?
Sandusky Bay where there are huge algal blooms
78
What causes the algal blooms in Sandusky Bay?
huge input of CO2 during the day from photosynthesis
79
What happens in Sandusky Bay at night?
respiration only
80
What are the major anions in inland waters?
CO3 2-, SO4 2-, Cl-
81
What are the major cations in inland waters?
Ca 2+, Mg 2+, Na+, K+
82
What is total solids number in inland waters made up of?
total suspended solids and total dissolved solids
83
How are total suspended solids (TSS) determined?
2 micrometer filter
84
How are total dissolved solids (TDS) determined?
passes through
85
What is the average TDS in rivers?
120 ppm
86
What is the TDS in oligotrophic Waldo Lake, OR?
1-5.5 ppm
87
What is the TDS in eutrophic Lake Itasca, MN?
185 ppm
88
What is the TDS in seas?
35000 ppm
89
What is the TDS in the Great Salt Lake, UT?
220,000 ppm
90
What is the TDS in Great Slave Lake, Canada?
160 ppm
91
What is the Great Slave Lake fed by?
the Slave River
92
What does the Slave River contribute to Great Slave Lake?
54000 metric tons of dissolved matter per summer day and 36000 tons of suspended silt per summer day
93
What activity occurs in Great Slave Lake?
some commercial fishing
94
What is the TDS of Great Bear Lake?
98 ppm
95
What is the Great Bear Lake ppm so low?
no comparable input of drainage area to Great Slave Lake, more oligotrophic, no commercial fishing
96
What is the shortcut to measuring TDS?
measure conductance (conducting)
97
What does conductance measure?
flow of electrons through water
98
Is distilled water a good conductor?
no
99
What salinity should not be used to measure conductance?
above 5%
100
What is the ion concentration in soft water lakes?
low
101
What is the ion concentration in hard water lakes?
high
102
What ions are present in lakes with high ion concentration?
Ca and Mg
103
What is the most common anion in dilute freshwater (humid)
Carbonate (CO3 2-)
104
What does DIC stand for?
dissolved organic carbon
105
What is the most common form of carbonate?
bicarbonate ion with calcium (Ca(CO3)2)
106
What other cations can carbonate combine with?
Magnesite (MgCO3), Dolomite (CaMg(CO3)2)), BaCO3, SrCO3, K2CO3, Na2CO3- magnesium, N/A, barium, strontium, potassium, sodium
107
What is the chemical formula for carbonate?
CO3 2-
108
What is the chemical formula for sulfate?
SO4 2-
109
How common is sulfate?
2nd most common anion
110
What are the atmospheric sources of sulfate?
volcanoes, industry, sea spray
111
What types of industry contribute to sulfate abundance?
coal combustion, copper smelting, and paper manufacturing
112
What are lakes near oceans and industry higher in?
sulfur
113
What do edaphic (soil) sources include?
old marine deposits
114
What are thioplasts?
organisms adapted in anaerobic, low pH habitats with lots of sulfur
115
What are the sulfur reducers?
CaSO4 + organic carbon > CaS+ 2CO2 + ATP
116
What are the sulfur oxidizers?
some can make their sugars (similar to photosynthesis), CO2 + 2H2S + light > CH2O + H2O +2S
117
What is the chemical formula of chloride?
Cl-
118
How common is chloride?
3rd most comon anion
119
Where is chloride most abundant?
seas and desert pools
120
What compounds does chloride form?
NaCl, MgCl2
121
What are the edaphic sources of chloride?
beds of salt formed from evaporation of former bodies of water
122
What are the beds of salt chloride is formed from called?
igneous rock
123
What are the atmospheric sources of chloride?
windblown from seacoasts and volcanic gases
124
What the water pollution sources of chloride?
pollution from sewage and highway salt (NaCl and CaCl2)
125
Where are there excess chloride ions?
Birch Lake MN
126
What is the chemical formula for calcium ions?
Ca 2+
127
What is CaCO3 the main constituent of?
chalk, limestone, marble
128
How does CaCO3 from chalk, limestone, and marble enter rivers and lakes?
chemical weathering
129
What calcerous deposit is deposited in littoral regions of lakes?
marl
130
What calcerous deposit is deposited around mineral springs?
sinter
131
What calcerous deposit evaporated in land salt lakes?
gypsum
132
Example of gypsum deposits
White Sands National Monument
133
What two ways can plants and animals react to calcium?
calciphiles and calciphobes
134
What is the chemical formula of Magnesium?
Mg 2+
135
How common is magnesium?
2nd most abundant cation
136
Where does magnesium come from?
erosion from rocks- silicates (rocks made of Mg and Si)
137
Chemical formula of sodium
Na+
138
What is NaCl?
a halite
139
How much NaCl does 1 liter of sea water have?
30g
140
What chemicals do salterns have?
NaCl and Na2SO4
141
What chemicals do soda lakes have?
NaHCO3 and Na2CO3
142
Chemical formula of potassium ions
K+
143
Where does potassium come from?
weathering of fledspar rocks
144
Which lakes are high in potassium?
Potash lakes
145
Where does no water runoff reach the ocean?
the desert
146
What exceeds what in the desert?
evaporation exceeds precipitation
147
What kind of basins are found in the desert?
closed
148
What is the Great Salt Lake?
saltern
149
What is the Dead Sea?
bittern
150
What happens in bitterns?
extreme evaporation
151
What variable is inversely correlated with salinity?
biodiversity
152
What type of lake is the Dead Sea?
rift lake
153
What 2 countries border the Dead Sea?
Israel and Jordan
154
What is the Dead Sea a part of?
the Great Rift Valley
155
What phenomenon occurs in lakes with high salt content?
buoyancy
156
What salinity is required for buoyancy?
>34%
157
What are two important reactions that occur in lakes?
oxidation and reduction
158
What is involved in oxidation and reduction reactions?
transfer of electrons (does not have to involve oxygen)
159
What type of reactions involve the coupling of electrons together?
redox reactions
160
Example of a redox reaction
iron oxidation
Fe 2+ (ferric) > Fe3+ (ferric) + e-
161
What is the molecule that loses an electron called?
reducing agent (ferrous ion in ex)
162
What is the molecule that gains an electron called?
oxidizing agent
163
What enzymes are iron necessary for?
peroxidase, catalase, cytochrome oxidase, nitrogenase
164
Why is iron necessary in photosynthesis?
part of cytochrome molecules
165
What is the oxidized state of iron?
ferrous
166
Solubility of ferrous iron
mostly soluble
167
What is the reduced state of iron?
ferric iron
168
Solubility of ferric iron
mostly insoluble
169
What is the redox of iron mediated by?
microorganisms
170
What does the elevation of oxygen levels promote?
oxidation of iron and thus precipitation since ferric is insoluble
171
Above what pH does iron automatically precipitate?
7.5-7.7
172
What does iron automatically precipitate into?
Fe(OH)3
173
Soluble/ferrous iron will only be present in which environments?
low oxygen environments (hypolimnion of a stratified lake) with a low to neutral pH
174
What are chelating agents?
class of compounds that can hold metal atoms or ions
175
What ion do chlorophylls hold?
magnesium
176
What can chelating agents do to ferric ions?
solubilize
177
What can release chelators?
microorganisms
178
What elements behaves similarly to iron?
manganese (Mn)
179
Why is manganese necessary in organisms?
as a co-factor for many enzymes
180
What oxidations states does manganese exist in?
Mn 2+, Mn 3+, Mn 4+
181
Does manganese become more or less soluble as it is oxidized?
less (just like iron)
182
What environment is soluble manganese present in and what will it do?
low-oxygen hypolimnion and will precipitate out during turnover
183
What are high levels of manganese toxic to?
fish and invertebrates
184
What is the most common form of phosphorus found in lakes and what form is it?
orthophosphate (PO4 3-), oxidized form (most common)
185
What gas can orthophosphate be reduced to?
PH3 (phosphine)
186
What does phosphine produced?
eerie lights that flicker over marshes (Will-o-the-wisps)
187
Why is the will-o-the-wisp flame fleeting?
it rapidly re-oxidizes
188
What is there very little of in the atmosphere?
P
189
What is the original source of phosphorus?
weathering of igneous rock
190
Where does phosphorus accumulate?
in skeletons of vertebrates and in bird guano
191
What pollution does phosphorus come from?
laundry detergents and sewage
192
What was phosphorus in the Rin lakes originally a limiting factor for?
primary production
193
What is phosphorus cycled rapidly into?
phytoplankton, littoral plants, and bacteria
194
Why do we worry about too much phosphorus now?
pollution
195
How was the study of phosphorus made easier in the 1950s?
using radioactive P32
196
What is it called when P32 is used to study phosphorus?
tracer study
197
What was there a huge effort to eliminate to prevent eutrophication due to pollution?
use of high-phosphate detergents
198
What is used to precipitate out phosphates in sewage?
FeCl2 or aluminum salts
199
What did Lake Erie being declared "dead" in the late 1960s lead to?
ban on phosphate detergents, invasive mussels helped reduce P, fish came back, P came back in recent years due to agricultural runoff
200
What is lake eutrophication caused by?
excessive P and N
201
What variable do scientists attempt to calculate in lake eutrophication?
critical load (Lc)
202
What is critical load?
the point where lakes go from oligotrophic to eutrophic
203
What was the first concentration of critical load calculations?
P
204
Why are big lakes less susceptible to pollution?
dilution
205
What else helps lakes be less susceptible to pollution?
high flushing rates
206
What is N2?
nitrogen gas in the atmosphere which is free and inert
207
What percentage of air does nitrogen gas make up?
78-79%
208
How is nitrogen gas harnessed?
must break the covalent triple bond, requires lots of ATP
209
Free nitrogen gas is unavailable to what?
plants and animals
210
How do plants and animals get nitrogen?
must be converted by prokaryotes
211
What lives symbiotically on roots of plants in the bean family?
Rhizobium
212
Cyanobacterium such as what are used in rice patties to increase nitrogen?
Anabaena
213
Nitrogen fixation reaction
N2 (nitrogen gas) > NH4+ (ammonium)
214
What enzyme is nitrogen fixation catalyzed by?
nitrogenase
215
What heavy isotope is used by tracer studies to measure nitrogen fixation?
15N
216
What element does nitrogenase break down in?
oxygen
217
Nitrogen fixation happens only in what conditions?
anaerobic
218
Wha special cells can nitrogen fixation also occur in?
heterocysts
219
Where are heterocysts present?
in some types of cyanobacteria (blue-green algae)
220
What is the process of nitrification?
NH4+ (ammonium) > NO2- (nitrite) > NO3- (nitrate)
221
What element is needed for nitrification?
oxygen
222
What organisms can perform nitrification?
only certain aerobic bacteria and archaea types
223
Where does NH4+ accumulate because nitrogen fixation is rare?
hypolimnion
224
What can accumulation of ammonium lead to?
hypoxia
225
What organism can assimilate ammonium, nitrates, and nitrites to make organic compounds
phytoplankton
226
By what process do dead organisms have their organic nitrogen (proteins) converted back to NH4+ by bacteria
ammonification
227
Why are lakes stratified longer in the summer?
global warming
228
What problem does global warming exacerbate?
loss of oxygen due to nitrification and leading to hypoxia
229
What can further exasperate oxygen loss due to nitrification?
oxygen loss due to hetertrophic respiration
230
What conditions does denitrification happen in?
anaerobic
231
Denitrification process
NO3- (nitrite) > N2 (nitrogen gas) and/or N2O (nitrogen oxide)
232
Where does denitrification occur?
swamps and marshlands
233
What is a consequence of denitrification?
nitrogen becomes unavailable to plants and animals
234
What is DNRA?
opposite of nitrification, nitrates/nitrites converted back to ammonia
235
What is anammox?
ammonia/nitrate converted directly to N2, same effect as denitrification
236
When was anammox discovered?
1999
237
What element is the limiting factor in coastal regions?
nitrogen
238
When does nitrogen become a limiting factor?
when P pollution is high
239
What type of bacteria is favored in eutrophic lakes?
nitrogen-fixing
240
What can be measured that is relevant to eutrophic lakes?
N/P ratio
241
Where does silica come from?
weathering of feldspar rocks
242
What is silica needed for?
silicean sponges, radiolarians (shells), and diatoms (cell walls)
243
Does solubility of silica increase or decrease with higher temps?
increase
244
Where is solubility of silica high?
geysers and hot springs
245
Why are diatoms important?
they are a major portion of the phytoplankton (photosynthesizers)
246
When can silica concentrations plummet?
at the end of summer
247
Where does silica go when diatoms die?
some is released to the water but some is lost to the sediment
248
Where does increased diatom growth cause eutrophication?
Great Lakes
249
What does the depletion of silica lead to?
cyanobacteria begin to outcompete diatoms
250
What quantity of inorganic micronutrients do plants require?
only trace quantities
251
What micronutrients are required by all algae?
chloride, iron, manganese, copper, molybdenum, zinc
252
What micronutrients are required by some algae?
cobalt, iodine, silicon, sodium, vanadium
253
What macronutrients are required by all algae?
Da, Mg, K, S, N, P
254
What are the poisonous heavy metals?
mercury, cadmium, and lead
255
What other poisons are popping up in lakes?
pharmaceuticals, pesticides, flame retardants, plastics, and microplastics
256
What are the 5 sources of dissolved organic substances?
decay of aquatic organisms (humus), excretions from phytoplankton, excretions from littoral plants, excretions from animals, allochthonous origins/washed in from outside sources
257
How does dissolved organic material impede light penetration?
absorbs solar radiation
258
Are lakes with high dissolved organic substances or nearby transparent lakes warmer?
lakes with high dissolved organic substances
259
What vitamins are essential to some algae and common in lakes?
biotin, thiamine, and B12
260
The study of vitamins in lakes is mostly limited to?
anthropogenic ones
261
What is the Redfield ratio?
C:N:P
262
Redfield ratio in oceans
106:16:1
263
The Redfield ratio is variable in?
lakes
264
What does LTER stand for?
Long Term Ecological Research Network
265
How many sites does the LTER have?
28
266
When was the LTER established?
1981 by NSF
267
Examples of LTERs?
North temperate lakes (Lake Mendota and Trout Lake, WI), Hubbard Brook Experimental Forest, NH, and Florida Coastal Everglades
268
LTER is both?
a physical place and a group of researchers
269
Where is the birthplace of limnology in the US?
University of Wisconsin @ Madison
270
What scientists are responsible for the birth of limnology?
E.A. Birge and Juday
271
When was limnology created?
Early 1900s
272
Where is Lake Mendota?
Madison, WI
273
What is Lake Mendota separated by?
isthmus
274
What is Lake Mendota joined by?
Yahara River
275
What Lake is called the most studied lake in the US?
Lake Mendota
276
Where is the University of Wisconsin at Madison located?
on the banks of Lake Mendota
277
University of Wisconsin at Madison has?
center for Limnology
278
What is the max depth of UW @ M's remote sensor buoy?
24.9
279
What is the pH of Lake Mendota?
8.3-8.4
280
How large is UW@M?
9781 acres
281
What was the focus of the Hubbard Brook Experimental Forest study?
the relationship between forest cover and water quality (specifically watersheds)
282
What does ELA stand for?
experimental lakes area
283
Where is the ELA?
Ontario, Canada
284
When were the ELAs experimented on?
late 1960s
285
What kind of experiments were the ELAs?
whole ecosystem experiments
286
What was the usual for ELAs?
controlled experiments from the labor field station (tanks), small scale studies in the lakes using bottles, and observational studies where variables were not manipulated
287
Characteristics of the ELAs
glacial lakes, pristine (not near any cities or towns), small, many of them, very little pollution from humans
288
Experiment done on the ELAs
divided, added C, N, PvsC, PvsN, showed that P was necessary for eutrophication, whole lake treated with mercury (simulated air pollution from coal burning power plants), accumulated in fish, spurred legislation for mercury scrubbers
289
What ethics were learned from the ELAs?
important studies, minimize # of times they are done, small isolated lakes, only experiments that the lake will quickly bounce back from, still seeing death of organisms, baseline data through time, any manipulation will have to be approved by the field station and the funding agencies
290
Where is Lake Victoria located?
East Africa
291
What is Lake Victoria called?
freshwater sea (almost the size of WV)
292
How many fish species are in Lake victoria?
300+
293
What is the current situation with Lake Victoria's fish?
today, all are threatened, endangered, or extinct
294
What type of lake is Lake Victoria?
African Rift Lake
295
Lake Vitoria is the 2nd largest freshwater lake by?
surface area (1st is superior)
296
How deep is Lake Victoria?
considered shallow, max depth 80m, average depth 40m
297
What countries surround Lake Victoria?
Kenya, Uganda, and Tanzania
298
Who is Lake Victoria named after?
Queen Victoria
299
80% of Lake Victoria's water is from?
rainfall
300
What is Lake Victoria drained by?
the Nile River
