Embed Size (px)
Citation preview
N, P, and isotopes from the nearshore/offshore Lake Erie nutrient study (NOLENS).
C.M. Pennuto1,2, A. Pérez-Fuentetaja1,2, A. Karatayev1,2, L. Burlakova1,2, G. Matisoff3, D. Bade4, J. Conroy5, E.A. Marschall5, and J. Kramer6.
1Biology Department, Buffalo State College, Buffalo, NY 2Great Lakes Center, Buffalo State College, Buffalo, NY
3Dept of Geological Sciences, Case Western Reserve University, Cleveland, OH 4Biology Department, Kent State University, Kent, OH
5Biology Department, The Ohio State University, Columbus, OH6National Center for Water Quality Research, Heidelberg University, Tiffin, OH
Sampling approach
• NS-to-OS transects bracketing major tribs to C & E basins…also allowed
coordination with other trib/watershed groups
• NS: R/V J.J. Freidhoff/whalers; OS: R/V Lake Guardian
• fixed stations (2, 5, 10, 20 m), June and late Aug/early Sept sampling
• quantify water column and benthic P pools…bacterial, phytoplankton, 3
zooplankton sizes, Dreissena mussels, dominant infaunal/epifaunal,
Cladophora, sediments (both mussel bed and non-mussel bed)
• estimate fluxes…bacterial and phytoplankton productivity, sedimentation
• link pools and fluxes via stable isotope analyses and hydrodynamic model of
particle transport
[P] in solid fractions[P] in benthic solid fractions
0
20
40
60
80
100
West-central (Sandusky)
Central (Grand) East (Cattaragaus)
Me
an [
P]
(m
g/g
)
Location
Sediment
Dreissena
Benthos
Cladophora
0
25
50
75
100
125
150
175
200
West-central (Sandusky)
Central (Grand) East (Cattaragaus)
Me
an d
ry m
ass
(g
/m2 )
Location
Sediment (*100-1)
Benthos
Dreissena
Cladophora
Benthic matrix quantities
Benthic matrix P amounts
0
25
50
75
100
West-central (Sandusky)
Central (Grand) East (Cattaragaus)
Me
an P
(g
/m2 )
Location
Sediment
Benthos
Dreissena
Cladophora
0
4
8
12
16
East (Catt Creek) Central (Grand) West-central (Sandusky)
[P]
(mg
/g)
20-m depth June
20-m depth September
0
5
10
15
20
West-central (Sandusky) Central (Grand) East (Cattaragaus)
Me
an m
uss
el
P (
mg
/m2 )
Location
2
5
10
20
Dreissena P amountsDepth
0
0.005
0.01
0.015
0.02
0.025
0.03
0.035
0.04
0.045
2 5 10 20 (14)
[TP
] (m
g/L)
Depth (m)
Water column [TP]Sandusky (west-central)Grand (central)Cattaraugus (east)June = black; Sept = white
0
2
4
6
8
10
12
14
2 5 10 20 (14)
Ch
l a(m
g/L)
Depth (m)
Sandusky (west-central)Grand (central)Cattaraugus (east)June = black; Sept = white
Water column [chl a]
0
200
400
600
800
1000
1200
1400
1600
2 5 10 20 (14)
Alg
al P
tu
rno
ver
(min
)
Depth (m)
Sandusky (west-central)Grand (central)Cattaraugus (east)June = black; Sept = white
Water column algal P-limitation
0
2
4
6
8
10
12
West (Sandusky) Central (Grand) East (Cattaragaus)
δN
1520-63 μm
63-210 μm
-30 -25 -20 -15 -10 -5 0
δN
15
δC13
Amphipod
Plankton
Oligochaete
Chironomid
Detritus
Benthos
Dreissena
Sediment
2
4
6
8
10
Results summary
• Distinct NS-to-OS reductions in water column [TP] at all 3 locations, WC & E basinincrease [TP] with season, but C decreased with season
• Algal abundance (chl a) matched [TP] in both seasons and across basins, decliningNS to OS and increasing or decreasing with [TP]; generally declining west to east
• Algal and bacterial communities were P-limited in the C, but not the WC or Ebasins in fall
• WC basin plankton exhibits a slightly higher δN, suggesting either longer chainsor a different basal resource
• The majority of organic particulate P resides in Dreissena tissues, but mussel abundance is very different in the basins and at different depths
• Sediments harbor the largest pool of P in the lake. Although C basin sediments have the highest [P] averaged across all depths, and the highest P pool, WC basin sediments have the highest OS [P]
Acknowledgments
GLNPO grant to CMP et al.
NSF-URM grant to CMP for summer students
Collaborators: G. MatisoffD. Bade
J. KramerS. Karatyev
A Perez-FuentatajaJ. Conroy
L. Burlakova
Students: M. HadjukC. Janik
C. VarascoC. Todd
K. James
