Supporting Information, Figure S1. Principal components analyses (PCA) of biweekly samples
collected May – August for all Qu’Appelle lakes except Pasqua during 2008 (a) and 2009 (b).
Symbols and abbreviations as in Fig. 5.
1.0
DOC
SRP TDP
EDA
(a)
TDN
DIC
DON
Urea
Lept
Diatom All(chla)
Siliceous
NH4
Green
ResTime NO3
pH
Cyano
Cop
Vol:Area
All(Bcar)
Vol
Crypto
O2
Temp
Zmx
Cyano(c)
Daph
Zmn
Area
Secchi
Axis 2 (19.92%)
Cond
Long
-1.0
-1.0
1.0
Axis 1 (27.3%)
1.0
Temp Cyano
Cop
Cond
All(Bcar)
Cyano(c)
DON
PH DOC EDA
WRT
All(chla)
TDP
SRP
Area
TDN
NH4
DIC
Vol
Diatom
Urea
Secchi
Green
Lept
Crypto
Zmx
Vol:Area
Siliceous
Long
Zmn
NO3
O2
Axis 2 (16.2%)
(b)
Daph
-1.0
-1.0
1.0
Axis1 (32.1%)
Bogard et al. Supporting Information, Fig. S1
Supporting Information, Table T1. Urea concentrations, uptake or decomposition (sum of uptake and
breakdown) and release rates from different freshwater locations. Data are presented as means (+ S.D.)
or as a range. Data were obtained both from published tables and independent interpretation of display
items, depending on source. Data was constrained to daytime samples from freshwater sources
obtained during spring or summer months, except for groundwater means which represent an annual
range, benthic sediment data which are derived from marine sources, and wetland data collected in
October. ‘Status’ refers to the trophic status of ecosystem, and includes O = oligotrophic, M =
mesotrophic, E = eutrophic, and H = hypereutrophic sites.
Urea
Location
Groundwater
Total Plankton (pelagic)
Concentration
Uptake or
Decomposition
Regeneration
Water Body
Status
Sample
Period
(g N L-1)
(g N L-1 h-1)
(g N L-1 h-1)
43.1 (+ 28.9 )
Well & Spring
E-H
Annual
28.8 (+ 2.9)
Well
O-M
Jul.
52.5
4.2
Lake Nakaumi
O-H
Nov.
11.5 - 33.6
1.2
Lake Balaton
M-E
May-Jun.
24.2 (+ 16.1)
2.9 (+ 0.3)
Lake Balaton Eutrophic Basin
E
Jul.-Sept.
0.9 (+ 0.4)
Lake Balaton Mesotrophic Basin
M
MayAug.
17 Lakes
M-H
Jun.
Pond
H
Jun.
Lake Biwa
M-H
Jun.
Lake Okeechobee
H
Jun.
29.9 (+ 13.6)
0.288 - 21.6
173.0
1.1
0.7 - 3.7
Phytoplankton (pelagic)
39.8
0.03
2.7
14.4 - 72.0
49.3
Smith Lake
H
May-Jun.
Zooplankton (pelagic)
~0.7 - 3.7
0.02
Lake Biwa
M-E
Jun.
Bacteria (pelagic)
0.7 - 3.7
0.01
Lake Biwa
M-E
Jun.
Pond
H
Jun.
Estuary
H
MayAug.
173.0
Sediment*
0.7
0.006
12734.4
7207.2 - 13213.4
Macrophyte biofilm
Flowing water
Oct.
67.2 - 128.8
Lake - benthic
E
Summer
95.2 - 162.4
Lake - littoral
E
Summer
132.5
60.0 - 120.1
Wetland
36.3 - 256.3
7.8 - 219.4
2 rivers
O
Mar.
2 streams
O
May
23.2
Oct.
9.1
0.1
Han River
M
83.4
0.0
Han River
H
*. Sedimentary rates are µg N m-2 h-1.
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