Electronic supplementary material for: Mathers, K.L. Millett, J. Robertson, A.L.
Stubbington, R. and Wood, P.J. Amphipod response to benthic and hyporheic
sedimentation varies with direction of vertical hydrological exchange. Freshwater
Biology.
Table S1. Fisher’s LSD post-hoc comparisons for G.pulex abundance. P-values are presented for
pairwise comparisons between the pattern of hydrological exchange for the same section / depth
(i.e. vertical position) and sediment treatment. Significant (P<0.05) results are emboldened.
Open gravel framework, Section A (0-50mm)
Hydrological
Downwelling
Upwelling
exchange
No exchange
0.004
<0.001
Downwelling
<0.001
Open gravel framework, Section B (50-100mm)
Hydrological
Downwelling
Upwelling
exchange
No exchange
0.725
0.161
Downwelling
0.080
Open gravel framework, Section C (100-150mm)
Hydrological
Downwelling
Upwelling
exchange
No exchange
0.815
0.349
Downwelling
0.242
Open gravel framework, Section D (150-200mm)
Hydrological
Downwelling
Upwelling
exchange
No exchange
0.907
0.558
Downwelling
0.640
Open gravel framework, Section E (200-250mm)
Hydrological
Downwelling
Upwelling
exchange
No exchange
0.129
<0.001
Downwelling
<0.001
3kg m-2 surface sedimentation, Section A (0-50mm)
Hydrological
Downwelling
Upwelling
exchange
No exchange
<0.001
0.725
Downwelling
<0.001
3kg m-2 surface sedimentation, Section B (50-100mm)
Hydrological
Downwelling
Upwelling
exchange
No exchange
0.413
0.002
Downwelling
0.020
3kg m-2 surface sedimentation, Section C (100-150mm)
Hydrological
Downwelling
Upwelling
exchange
No exchange
0.413
0.242
Downwelling
0.725
3kg m-2 surface sedimentation, Section D (150-200mm)
Hydrological
Downwelling
Upwelling
exchange
No exchange
0.292
0.907
Downwelling
0.242
3kg m-2 surface sedimentation, Section E (200-250mm)
Hydrological
Downwelling
Upwelling
exchange
No exchange
<0.001
<0.001
Downwelling
<0.001
5kg m-2 benthic sedimentation, Section A (0-50mm)
Hydrological
Downwelling
Upwelling
exchange
No exchange
<0.001
0.725
Downwelling
0.036
5kg m-2 benthic sedimentation, Section B (50-100mm)
Hydrological
Downwelling
Upwelling
exchange
No exchange
Downwelling
5kg m-2 benthic sedimentation, Section C (100-150mm)
Hydrological
Downwelling
Upwelling
exchange
No exchange
0.036
0.129
Downwelling
0.062
5kg m-2 benthic sedimentation, Section D (150-200mm)
Hydrological
Downwelling
Upwelling
exchange
No exchange
0.349
0.558
Downwelling
0.725
5kg m-2 benthic sedimentation, Section E (200-250mm)
Hydrological
Downwelling
Upwelling
exchange
No exchange
0.010
<0.001
Downwelling
<0.001
3kg m-2 subsurface sedimentation of one section, Section A (0-50mm)
Hydrological
Downwelling
Upwelling
exchange
No exchange
0.036
0.242
Downwelling
0.001
3kg m-2 subsurface sedimentation of one section, Section B (50-100mm)
Hydrological
Downwelling
Upwelling
exchange
No exchange
<0.001
<0.001
Downwelling
0.010
3kg m-2 subsurface sedimentation of one section, Section C (100-150mm)
Hydrological
Downwelling
Upwelling
exchange
No exchange
0.014
0.161
Downwelling
<0.001
3kg m-2 subsurface sedimentation of one section, Section D (150-200mm)
Hydrological
Downwelling
Upwelling
exchange
No exchange
0.102
0.198
Downwelling
0.725
3kg m-2 subsurface sedimentation of one section, Section E (200-250mm)
Hydrological
Downwelling
Upwelling
exchange
No exchange
0.815
<0.001
Downwelling
<0.001
3kg m-2 subsurface sedimentation of three sections, Section A (0-50mm)
Hydrological
Downwelling
Upwelling
exchange
No exchange
0.349
<0.001
Downwelling
<0.001
3kg m-2 subsurface sedimentation of three sections, Section B (50-100mm)
Hydrological
Downwelling
Upwelling
exchange
No exchange
0.198
0.161
Downwelling
0.907
3kg m-2 subsurface sedimentation of three sections, Section C (100-150mm)
Hydrological
Downwelling
Upwelling
exchange
No exchange
0.815
0.047
Downwelling
0.027
3kg m-2 subsurface sedimentation of three sections, Section D (150-200mm)
Hydrological
Downwelling
Upwelling
exchange
No exchange
0.349
0.047
Downwelling
0.292
3kg m-2 subsurface sedimentation of three sections, Section E (200-250mm)
Hydrological
Downwelling
Upwelling
exchange
No exchange
0.815
0.047
Downwelling
0.027
3kg m-2 surface and subsurface sedimentation (all sections), Section A (0-50mm)
Hydrological
Downwelling
Upwelling
exchange
No exchange
<0.001
0.161
Downwelling
0.027
3kg m-2 surface and subsurface sedimentation (all sections), Section B (50-100mm)
Hydrological
Downwelling
Upwelling
exchange
No exchange
0.047
0.292
Downwelling
0.002
3kg m-2 surface and subsurface sedimentation (all sections), Section C (100-150mm)
Hydrological
Downwelling
Upwelling
exchange
No exchange
0.198
0.558
Downwelling
0.483
3kg m-2 surface and subsurface sedimentation (all sections), Section D (150-200mm)
Hydrological
Downwelling
Upwelling
exchange
No exchange
0.815
1.000
Downwelling
0.815
3kg m-2 surface and subsurface sedimentation (all sections), Section E (200-250mm)
Hydrological
Downwelling
Upwelling
exchange
No exchange
0.907
0.413
Downwelling
0.483
Table S2. Fisher’s LSD post-hoc comparisons for G.pulex abundance under no exchange conditions.
P-values are presented for pairwise comparisons between sediment treatments for the same
section /depth (i.e. vertical position). Significant (P<0.05) results are emboldened. Sediment
treatments; 1=open gravel framework; 2 = 3kg m-2 surface sedimentation; 3 = 5kg m-2 surface
sedimentation; 4 = 3kg m-2 subsurface sedimentation of one section; 5 = 3kg m-2 subsurface
sedimentation of three sections and; 6= 3kg m-2 surface and subsurface sedimentation (all sections).
Section A: 0-50mm
Sediment
2
3
treatment
1
<0.001 0.047
2
0.129
3
4
5
Section B: 50-100mm
Sediment
2
treatment
1
0.161
2
3
4
5
Section C: 100-150mm
Sediment
2
treatment
1
0.3907
2
3
4
5
Section D: 150-200mm
Sediment
2
treatment
1
0.640
2
3
4
5
Section E: 200-250mm
Sediment
2
treatment
1
0.014
2
3
4
5
4
5
6
0.198
0.027
0.483
<0.001
<0.001
<0.001
<0.001
<0.001
<0.001
<0.001
<0.001
0.10
3
4
5
6
0.002
0.080
<0.001
<0.001
0.020
0.027
0.413
0.349
0.001
0.242
0.815
0.047
<0.001
0.292
3
4
5
6
0.558
0.640
0.815
0.725
0.413
0.640
0.725
0.907
0.483
0.292
0.242
0.102
0.413
0.129
3
4
5
6
0.815
0.815
0.349
0.161
0.242
0.413
0.198
0.292
0.907
0.242
0.102
0.161
0.815
0.725
3
4
5
6
0.640
0.004
0.198
<0.001
0.143
0.004
<0.001
0.014
0.102
0.001
<0.001
0.005
0.047
0.725
Table S3. Fisher’s LSD post-hoc comparisons for G.pulex abundance under downwelling flow
conditions. P-values are presented for pairwise comparisons between sediment treatments for the
same section / depth (i.e. vertical position). Significant (P<0.05) results are emboldened. Sediment
treatments; 1=open gravel framework; 2 = 3kg m-2 surface sedimentation; 3 = 5kg m-2 surface
sedimentation; 4 = 3kg m-2 subsurface sedimentation of one section; 5 = 3kg m-2 subsurface
sedimentation of three sections and; 6= 3kg m-2 surface and subsurface sedimentation (all sections).
Section A: 0-50mm
Sediment
2
treatment
1
0.001
2
3
4
5
Section B: 50-100mm
Sediment
2
treatment
1
0.815
2
3
4
5
Section C: 100-150mm
Sediment
2
treatment
1
0.349
2
3
4
5
Section D: 150-200mm
Sediment
2
treatment
1
0.483
2
3
4
5
Section E200-250mm
Sediment
2
treatment
1
0.292
2
3
4
5
3
4
5
6
0.007
0.483
0.036
<0.001
<0.001
0.815
<0.001
0.004
0.062
0.725
<0.001
0.002
0.080
0.907
3
4
5
6
0.483
0.640
0.349
0.483
0.815
0.558
0.725
0.907
0.725
0.005
0.010
0.036
0.062
0.027
3
4
5
6
1.000
0.349
0.047
0.004
0.047
0.242
0.036
0.242
0.413
1.000
0.349
1.000
0.047
0.242
3
4
5
6
0.413
0.907
0.558
0.198
0.161
1.000
0.483
0.413
0.558
0.292
0.725
0.815
0.102
0.292
3
4
5
6
0.29
0.640
1.000
0.292
0.129
0.102
0.558
0.907
0.102
0.102
0.558
0.907
0.102
1.000
Table S4. Fisher’s LSD post-hoc comparisons for abundance under upwelling flow conditions. Pvalues are presented for pairwise comparisons between sediment treatments for the same section /
depths (i.e. vertical position). Significant (P<0.05) results are emboldened. Sediment treatments;
1=open gravel framework; 2 = 3kg m-2 surface sedimentation; 3 = = 5kg m-2 surface sedimentation;
4 = 3kg m-2 subsurface sedimentation of one section; 5 = 3kg m-2 subsurface sedimentation of three
sections and; 6= 3kg m-2 surface and subsurface sedimentation (all sections).
Section A: 0-50mm
Sediment
2
treatment
1
0.907
2
3
4
5
Section B: 50-100mm
Sediment
2
treatment
1
0.725
2
3
4
5
Section C: 100-150mm
Sediment
2
treatment
1
0.907
2
3
4
5
Section D: 150-200mm
Sediment
2
treatment
1
1.000
2
3
4
5
Section E: 200-250mm
Sediment
2
treatment
1
0.640
2
3
4
5
3
4
5
6
0.161
0.129
0.198
0.161
0.907
0.010
0.007
0.242
0.198
<0.001
<0.001
<0.001
<0.001
<0.001
3
4
5
6
0.349
0.198
0.907
0.640
0.413
0.027
0.010
0.198
0.036
0.129
0.062
0.558
0.161
0.483
3
4
5
6
0.725
0.815
0.483
0.558
0.725
0.014
0.010
0.005
0.002
0.640
0.558
0.413
0.242
0.047
3
4
5
6
0.349
0.349
0.815
0.815
0.483
0.558
0.558
0.129
0.413
0.080
0.080
0.413
0.129
0.020
3
4
5
6
0.198
0.080
0.102
0.036
0.725
<0.001
<0.001
<0.001
<0.001
<0.001
<0.001
<0.001
<0.001
0.129