phytoplankton community structure in the river-influenced

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The following supplement accompanies the article

Phytoplankton community structure in the river-influenced continental margin of the northern Gulf of Mexico

Sumit Chakraborty, Steven E. Lohrenz*

*Corresponding author: [email protected]

Marine Ecology Progress Series 521: 31-47 (2015)

Supplement. This supplement includes dendrograms from the cluster analysis of water mass hydrographic properties (Fig. S1) and mean seasonal profiles of temperature, salinity, sigma-t and chlorophyll fluorescence (Fig. S2). Additional information includes CHEMTAX output of chl a to pigment ratios for different phytoplankton groups and water mass types (Table S1), pigment to total accessory pigment ratios for different seasons and water mass regimes (Table S2), CHEMTAX-derived contributions to chl a by taxonomic groups of phytoplankton (Table S3), and eigenvectors for the PCA analysis for the different water mass types (Table S4).

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Fig. S1. Cluster analysis (dendrograms) for the different hydrographic regimes (water mass types). Distance is a relative measure of separation (standardized unit variance)

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Fig. S2. Seasonal variations in temperature, salinity, sigma-t and chlorophyll fluorescence for the inner shelf regime. The lines represent the means and the gray shaded areas represent the standard errors

Fluorescence (mg m-3)

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Fig. S2 (continued). Seasonal variations in temperature, salinity, sigma-t and chlorophyll fluorescence for midshelf regime. The lines represent the means and the gray shaded areas represent the standard errors

5

Fig. S2 (continued). Seasonal variations in temperature, salinity, sigma-t and chlorophyll fluorescence for slope (offshore) regime. The lines represent the means and the gray shaded areas represent the standard errors

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Table S1. Output from CHEMTAX of pigment to chl a ratios for the different phytoplankton groups and water mass types Chlc3 Chlc2 Peri 19But Fuco Neo Pras Viola 19Hex Ddx Allo Zea Lut chlb

Dinoflagellates Estuarine-Inner shelf-Midshelf - 0.172 0.889 - - - - - - 0.167 - - - - Slope - 0.212 0.916 - - - - - - 0.079 - - - -Deep - 0.092 0.67 - - - - - - 0.039 - - - - Diatoms Estuarine-Inner shelf-Midshelf - 0.1522 - - 0.5356 - - - - 0.102 - - - -Slope - 0.103 - - 0.413 - - - - 0.0665 - - - -Deep - 0.301 - - 0.801 - - - - 0.1715 - - - -Chlorophytes Estuarine-Inner shelf-Midshelf - - - - - 0.054 - 0.028 - - - 0.0586 0.1859 0.1783Cryptophytes Estuarine-Inner shelf-Midshelf - 0.0385 - - - - - - - - 0.273 - - -Slope - 0.1105 - - - - - - - - 0.1912 - - -Deep - 0.1105 - - - - - - - - 0.1915 - - -Prasinophyte-I Estuarine-Inner shelf-Midshelf - - - - - 0.055 0.285 0.034 - - - 0.0329 0.0059 0.6738Slope - - - - - 0.0417 0.1308 0.083 - - - 0.04 - 0.8057Deep - - - - - 0.055 0.1869 0.052 - - - 0.02 - 1.014PrasinophyteII Estuarine-Inner shelf - - - - - 0.037 - 0.071 - - - 0.0262 0.079 0.7664Haptophyte-6 Estuarine-Inner shelf-Midshelf 0.1755 0.1876 - 0.007 0.0193 - - - 0.78 0.018 - - - -Slope 0.1854 0.1826 - 0.0068 0.117 - - - 0.806 0.109 - - - -Deep 0.2704 0.244 - 0.007 0.283 - - - 1.126 0.099 - - - -Haptophyte-8 Estuarine-Inner shelf-Midshelf 0.2702 0.121 0.204 0.1087 - - - 0.261 0.073 - - - -Slope 0.193 0.988 0.189 0.885 - - - 0.383 0.094 - - - -Deep 0.204 0.114 0.1776 0.098 - - - - 0.086 - - - -Pelagophyte Midshelf -Slope 0.195 0.0934 - 0.8651 0.6743 - - - - 0.279 - - - -Deep 0.66 0.2837 - 1.049 0.1 - - - - 0.093 - - - -

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Table S1 (continued)

Chlc3 Chlc2 Peri 19But Fuco Neo Pras Viola 19Hex Ddx Allo Zea DVChlb Chlb DVChla Cyanobacteria Estuarine-Inner shelf-Midshelf - - - - - - - - - - - 0.5053 - - - Slope - - - - - - - - - - - 0.6074 - - - Deep - - - - - - - - - - - 0.454 - - - Prochlorophyte Slope - - - - - - - - - - - 0.4793 0.5597 - 1 Deep - - - - - - - - - - - 0.242 1.02 - 1

Choice of initial ratios

The taxonomic groups considered for the analysis were based on prior knowledge of phytoplankton in the region (Dortch & Whitledge 1992, Redalje et al. 1994, Bode & Dortch 1996, Lohrenz et al. 1999, Chen et al. 2000, Jochem 2003, Qian et al. 2003, Wawrik et al. 2003, Dagg et al. 2004, Wawrik & Paul 2004, Wysocki et al. 2006) and limited microscopic analyses during the cruises. Initial ratios selected for the relevant taxonomic groups were from values provided in previous studies (Gieskes & Kraay 1986, Jeffrey et al. 1997, Mackey et al. 1998, Schlüter et al. 2000, Schlüter & Møhlenberg 2003, Latasa et al. 2004, Veldhuis & Kraay 2004, Zapata et al. 2004, Rodríguez et al. 2005, Laza-Martinez et al. 2007, Seoane et al. 2009). Pigment ratios were also determined for selected phytoplankton taxa (Thalassiosira spp., Skeletonema spp., Nitzschia spp., Phaeodactylum spp., Dunaliella sp., and Isochrysis spp.) maintained in batch culture (FCRG medium, described in Eppley et al. 1967, 20oC, 12:12 light:dark cycle).

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Table S2. Pigment:TAccp ratios for different seasons and water mass regimes, mean ± standard deviations. Bold numbers represent significant differences between slope (surface) and slope-CFM (Mann-Whitney U test)

chlc3:TAccp

chlc2c1:TAccp

peri:TAccp

19'-but:TAccp

fuco:TAccp

pras:TAccp

19'-hex:TAccp

ddx:TAccp

allo:TAccp

diato:TAccp

zea:TAccp DVchlb:TAccp

chlb:TAccp

DVchla:TAccp

caro:TAccp

Winter

Inner shelf 0.019 ± 0.020

0.137 ± 0.055

0.029 ± 0.093

0.002 ± 0.005

0.523 ± 0.151

0.000 ± 0.001

0.017 ± 0.020

0.074 ± 0.027

0.028 ± 0.031

0.012 ± 0.013

0.030 ± 0.036

nd 0.067 ± 0.068

nd 0.044 ± 0.023

Midshelf 0.069 ± 0.021

0.127 ± 0.032

0.006 ± 0.011

0.018 ± 0.017

0.362 ± 0.097

0.005 ± 0.016

0.073 ± 0.043

0.053 ± 0.011

0.013 ± 0.008

0.016 ± 0.027

0.054 ± 0.039

nd 0.155 ± 0.064

0.005 ± 0.016

0.035 ± 0.008

slope

surface 0.093 ± 0.018

0.102 ± 0.024

0.001 ± 0.003

0.070 ± 0.029

0.125 ± 0.100

nd 0.166 ± 0.052

0.035 ± 0.012

0.014 ± 0.010

0.011 ± 0.023

0.133 ± 0.079

0.018 ± 0.019

0.174 ± 0.046

0.136 ± 0.124

0.045 ± 0.030

CFM 0.122 ± 0.025

0.115 ± 0.025

0.002 ± 0.004

0.091 ± 0.036

0.197 ± 0.126

0.001 ± 0.004

0.169 ± 0.066

0.035 ± 0.009

0.016 ± 0.009

0.005 ± 0.008

0.078 ± 0.037

nd 0.157 ± 0.048

0.065 ± 0.064

0.040 ± 0.011

p-value 0.02

Deep (≥100 m)

0.128 ± 0.020

0.082 ± 0.020

0.001 ± 0.002

0.137 ± 0.026

0.121 ± 0.040

0.001 ± 0.006

0.196 ± 0.033

0.014 ± 0.013

0.004 ± 0.007

0.000 ± 0.000

0.036 ± 0.031

0.147 ± 0.162

0.118 ± 0.082

0.060 ± 0.026

0.013 ± 0.018

Spring 2009


0.158 ± 0.074

0.024 ± 0.060

0.000 ± 0.000

0.498 ± 0.079

0.002 ± 0.003

0.006 ± 0.010

0.092 ± 0.031

0.029 ± 0.025

0.011 ± 0.006

0.025 ± 0.023

nd 0.078 ± 0.052

0.000 ± 0.000

0.046 ± 0.018

Midshelf 0.039 ± 0.049

0.188 ± 0.294

0.011 ± 0.024

0.004 ± 0.004

0.451 ± 0.687

0.002 ± 0.005

0.032 ± 0.018

0.090 ± 0.116

0.018 ± 0.035

0.012 ± 0.016

0.056 ± 0.025

nd 0.066 ± 0.120

0.007 ± 0.011

0.038 ± 0.049

slope

surface 0.042 ± 0.040

0.064 ± 0.029

0.008 ± 0.011

0.057 ± 0.029

0.089 ± 0.056

nd 0.150 ± 0.029

0.056 ± 0.025

0.000 ± 0.002

0.006 ± 0.011

0.407 ± 0.136

0.007 ± 0.012

0.060 ± 0.082

0.248 ± 0.093

0.051 ± 0.035

CFM 0.104 ± 0.037

0.041 ± 0.024

0.007 ± 0.019

0.092 ± 0.043

0.070 ± 0.047

0.006 ± 0.008

0.182 ± 0.035

0.009 ± 0.005

0.003 ± 0.002

0.000 ± 0.000

0.033 ± 0.011

0.065 ± 0.057

0.081 ± 0.053

0.097 ± 0.033

0.002 ± 0.003

p-value 0.002 0.003 0.009

Deep (≥100 m)

0.022 ± 0.021

0.017 ± 0.019

0.000 ± 0.000

0.024 ± 0.024

0.027 ± 0.032

0.009 ± 0.005

0.026 ± 0.030

0.004 ± 0.004

0.001 ± 0.002

0.000 ± 0.000

0.009 ± 0.017

0.024 ± 0.032

0.020 ± 0.035

0.024 ± 0.016

0.005 ± 0.007

Summer


0.089 ± 0.046

0.045 ± 0.098

0.004 ± 0.008

0.288 ± 0.138

nd 0.042 ± 0.053

0.070 ± 0.034

0.021 ± 0.022

0.011 ± 0.009

0.226 ± 0.128

nd 0.087 ± 0.038

0.009 ± 0.040

0.080 ± 0.034

Midshelf 0.044 ± 0.023

0.090 ± 0.032

0.026 ± 0.019

0.011 ± 0.011

0.163 ± 0.124

nd 0.128 ± 0.046

0.076 ± 0.022

0.002 ± 0.004

0.009 ± 0.007

0.315 ± 0.152

0.002 ± 0.005

0.069 ± 0.038

0.063 ± 0.112

0.062 ± 0.021

slope

surface 0.039 ± 0.025

0.088 ± 0.046

0.017 ± 0.017

0.003 ± 0.004

0.149 ± 0.152

nd 0.143 ± 0.067

0.060 ± 0.025

0.002 ± 0.006

0.008 ± 0.008

0.328 ± 0.183

0.002 ± 0.006

0.061 ± 0.040

0.149 ± 0.156

0.067 ± 0.038

CFM 0.131 ± 0.053

0.092 ± 0.023

0.002 ± 0.007

0.082 ± 0.031

0.138 ± 0.119

0.016 ± 0.008

0.153 ± 0.048

0.022 ± 0.007

0.004 ± 0.005

0.001 ± 0.004

0.051 ± 0.026

0.161 ± 0.121

0.149 ± 0.142

0.208 ± 0.187

0.010 ± 0.011

p-value 0.001 0.002 0.001 0.007 0.003

Deep (≥100 m)

0.089 ± 0.028

0.066 ± 0.016

0.000 ± 0.000

0.097 ± 0.023

0.117 ± 0.084

0.011 ± 0.003

0.139 ± 0.022

0.016 ± 0.009

0.000 ± 0.000

0.000 ± 0.000

0.042 ± 0.025

0.279 ± 0.227

0.154 ± 0.192

0.175 ± 0.111

0.001 ± 0.002

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Table S2 (continued)

chlc3:TAccp

chlc2c1:TAccp

peri:TAccp

19'-but:TAccp

fuco:TAccp

pras:TAccp

19'-hex:TAccp

ddx:TAccp

allo:TAccp

diato:TAccp

zea:TAccp DVchlb:TAccp

chlb:TAccp

DVchla:TAccp

caro:TAccp

Fall


0.118 ± 0.055

0.033 ± 0.035

0.002 ± 0.004

0.397 ± 0.104

0.004 ± 0.008

0.015 ± 0.020

0.063 ± 0.021

0.059 ± 0.031

0.011 ± 0.013

0.068 ± 0.050

nd 0.137 ± 0.057

nd 0.056 ± 0.026

Midshelf 0.062 ± 0.055

0.125 ± 0.105

0.021 ± 0.035

0.022 ± 0.020

0.251 ± 0.185

0.003 ± 0.009

0.077 ± 0.056

0.056 ± 0.044

0.023 ± 0.025

0.031 ± 0.096

0.140 ± 0.160

0.013 ± 0.024

0.115 ± 0.057

0.118 ± 0.198

0.042 ± 0.017

slope(surface) surface 0.057 ±

0.021 0.072 ± 0.029

0.006 ± 0.007

0.005 ± 0.001

0.098 ± 0.074

0.003 ± 0.009

0.152 ± 0.026

0.032 ± 0.014

0.005 ± 0.010

0.001 ± 0.003

0.350 ± 0.170

0.039 ± 0.031

0.097 ± 0.093

0.362 ± 0.235

0.029 ± 0.018

CFM 0.084 ± 0.014

0.014 ± 0.000

0.000 ± 0.000

0.025 ± 0.000

0.014 ± 0.000

0.009 ± 0.004

0.158 ± 0.043

0.005 ± 0.000

0.003 ± 0.000

0.000 ± 0.000

0.087 ± 0.052

0.319 ± 0.112

0.106 ± 0.052

0.315 ± 0.113

0.001 ± 0.000

p-value 0.002 0.001 0.001 0.001

Deep (≥100 m)

0.087 ± 0.021

0.036 ± 0.023

0.000 ± 0.000

0.088 ± 0.027

0.053 ± 0.039

0.004 ± 0.002

0.133 ± 0.015

0.017 ± 0.016

0.002 ± 0.005

0.001 ± 0.002

0.098 ± 0.173

0.451 ± 0.237

0.027 ± 0.023

0.213 ± 0.051

0.008 ± 0.018

Spring 2010


0.140 ± 0.060

0.139 ± 0.125

0.002 ± 0.005

0.380 ± 0.152

0.001 ± 0.003

0.004 ± 0.009

0.152 ± 0.066

0.035 ± 0.019

0.009 ± 0.009

0.004 ± 0.005

nd 0.059 ± 0.036

nd 0.042 ± 0.014

Midshelf 0.025 ± 0.028

0.141 ± 0.024

0.082 ± 0.076

0.008 ± 0.011

0.420 ± 0.127

0.001 ± 0.002

0.021 ± 0.031

0.135 ± 0.041

0.031 ± 0.019

0.016 ± 0.007

0.005 ± 0.004

nd 0.070 ± 0.046

nd 0.035 ± 0.004

slope(surface) surface 0.090 ±

0.039 0.132 ± 0.027

0.000 ± 0.000

0.038 ± 0.023

0.278 ± 0.152

0.012 ± 0.017

0.140 ± 0.080

0.060 ± 0.026

0.021 ± 0.012

0.011 ± 0.010

0.034 ± 0.032

nd 0.142 ± 0.115

nd 0.028 ± 0.011

CFM 0.134 ± 0.067

0.124 ± 0.025

0.022 ± 0.058

0.068 ± 0.030

0.292 ± 0.130

0.015 ± 0.015

0.137 ± 0.061

0.038 ± 0.010

0.021 ± 0.018

0.001 ± 0.003

0.019 ± 0.024

nd 0.198 ± 0.071

0.001 ± 0.001

0.021 ± 0.013

p-value 0.03 0.01 0.01

Deep (≥100 m)

0.045 ± 0.052

0.155 ± 0.110

0.000 ± 0.000

0.033 ± 0.043

0.436 ± 0.262

nd 0.054 ± 0.076

0.017 ± 0.022

0.118 ± 0.121

0.000 ± 0.000

0.007 ± 0.008

nd 0.115 ± 0.184

0.001 ± 0.002

0.013 ± 0.015

nd = not detected

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Table S3. Average percent (mean ± SD) contributions to chl a by taxonomic groups of phytoplankton as derived from CHEMTAX Dinoflagellates Diatoms Chlorophytes Cryptophytes Prasinophytes-I Prasinophytes-II Haptophytes-6 Haptophytes-8 Pelagophytes Cyanobacteria Prochlorophytes

Winter

Estuarine_Inner shelf 2.473 ± 7.551 65.616 ± 20.515 6.065 ± 9.357 15.317 ± 9.089 1.099 ± 2.720 3.279 ± 4.581 0.323 ± 0.557 2.754 ± 2.603 - 3.073 ± 4.142 -

Midshelf 0.352 ± 0.423 47.255 ± 13.794 3.447 ± 2.128 6.711 ± 4.027 14.933 ± 7.185 - 2.811 ± 2.873 16.445 ± 6.628 0.617 ± 2.047 7.127 ± 5.166 0.301 ± 0.942

Slope 3.309 ± 1.604 11.938 ± 10.121 1.75 ± 0.08 0.00 ± 0.00 3.12 ± 1.104 - 12.852 ± 7.778 19.815 ± 2.904 4.742 3.494 25.44 ± 9.824 17.034 ± 9.907

CFM 1.87 ± 0.972 7.022 ± 6.125 1.12 ± 1.672 3.065 ± 0.696 4.3 ± 3.986 - 9.006 ± 12.516 27.944 ± 24.845 16.307 ± 7.431 10.594 ± 7.625 18.772 ± 21.47

Deep 2.435 ± 5.361 9.774 ± 6.771 0.00 ± 0.00 0.512 ± 0.022 1.11 ± 0.06 - 14.118 ± 12.493 18.007 ± 21.116 15.12 ± 9.146 5.613 ± 8.95 33.311 ± 16.315

Spring 2009


Midshelf 2.135 ± 6.567 33.433 ± 28.920 2.360 ± 4.170 4.082 ± 4.208 4.564 ± 4.415 - 8.793 ± 6.732 6.901 ± 12.391 3.181 ± 2.415 28.151 ± 21.736 6.398 ± 8.162

Slope 0.561 ± 1.011 5.784 ± 8.689 1.01 ± 0.2 1.51 ± 0.876 0.464 ± 0.512 - 17.561 ± 6.005 1.898 ± 1.690 2.625 ± 5.609 50.846 ± 14.182 17.74 ± 5.026

CFM 4.21 ± 8.23 4.39 ± 6.752 4.78 ± 2.818 5.018 ± 2.941 2.36 ± 3.573 - 19.713 ± 7.367 6.52 ± 7.14 8.869 ± 5.061 15.744 ± 17.355 28.396 ± 16.475

Deep 1.035 ± 3.449 6.96 ± 8.745 0.00 ± 0.00 0.06 ± 0.12 1.5 ± 1.12 - 11.326 ± 9.83 7.464 ± 9 19.712 ± 9.781 3.335 ± 5.22 48.068 ± 16.219

Summer

Estuarine_Inner shelf 5.046 ± 11.525 38.904 ± 12.977 4.346 ± 7.724 11.851 ± 11.133 0.568 ± 0588 5.368 ± 3.527 2.149 ± 3.050 2.883 ± 3.080 - 28.885 ± 20.786 -

Midshelf 1.822 ± 1.894 13.100 ± 16.271 1.696 ± 2.762 2.420 ± 2.929 8.216 ± 6.069 - 14.936 ± 4.968 3.315 ± 4.769 3.114 ± 4.337 44.893 ± 16.570 6.489 ± 7.129

Slope 1.337 ± 1.61 26.098 ± 30.779 0.00 ± 0.00 2.06 ± 2.54 1.43 ± 0.745 - 14.408 ± 8.755 1.0671 ± 1.952 1.677 ± 1.428 41.178 ± 19.764 10.744 ± 10.036

CFM 0.241± 0.682 10.468 ± 16.944 1.78 ± 0.392 1.849 ± 2.447 3.005 ± 2.932 - 15.261 ± 4.465 9.757 ± 15.26 9.181 ± 3.611 5.284 ± 2.141 43.174 ± 25.627

Deep 0.654 ± 0.924 8.059 ± 10.479 0.00 ± 0.00 2.001 ± 2.458 0.00 ± 0.00 - 11.712 ± 5.347 10.036 ± 13.153 13.224 ± 4.158 3.66 ± 5.985 50.654 ± 23.792

Fall


Midshelf 0.936 ± 0.555 19.230 ± 17.400 1.491 ± 2.089 6.099 ± 5.621 9.525 ± 6.182 - 8.434 ± 6.523 13.335 ± 13.281 2.739 ± 4.577 22.018 ± 18.773 16.193 ± 18.929

Slope 0.69 ± 0.14 2.254 ± 4.858 0.00 ± 0.00 0.00 ± 0.00 0.373 ± 1.001 - 16.58 ± 2.716 2.267 ± 1.657 2.542 ± 1.027 43.09 ± 15.126 32.196 ± 15.612

CFM 1.248 ± 0.452 2.526 ± 5.074 1.324 ± 1.563 1.298 ± 0.618 3.06 ± 3.863 - 12.325 ± 4.465 3.136 ± 7.818 9.957 ± 3.447 3.471 ± 1.69 58.423 ± 17.641

Deep 0.603 ± 0.254 1.775 ± 2.823 0.00 ± 0.00 0.00 ± 0.00 0.5 ± 0.653 - 12.908 ± 3.132 0.776 ± 1.92 10.775 ± 4.753 11.012 ± 21.103 61.651 ± 17.718

Spring 2010


Midshelf 4.677 ± 5.735 63.74 ± 11.509 3.934 ± 2.124 9.997 ± 4.433 7.644 ± 5.105 - 2.053 ± 2.188 5.867 ± 4.473 0.900 ± 0.964 1.189 ± 1.352 0.00 ± 0.00

Slope 5.925 ± 2.006 28.48 ± 19.601 4.943 ± 3.217 6.943 ± 1.325 4.107 ± 2.76 - 13.86 ± 8.175 24.78 ± 10.817 3.943 ± 2.733 6.096 ± 6.734 0.00 ± 0.00

CFM 4.479 ± 5.806 30.836 ± 27.341 4.469 ± 3.937 4.644 ± 6.739 5.75 ± 4.749 - 9.906 ± 6.377 19.021 ± 13.23 15.508 ± 3.063 5.387 ± 3.177 0.00 ± 0.00

Deep 2.109 ± 3.818 22.521 ± 33.588 0.00 ± 0.00 2.28 ± 1.653 0.00 ± 0.00 - 13.12 ± 14.281 21.032 ± 21.533 11.653 ± 16.79 11.197 ± 6.605 16.088 ± 6.144

11

Table S4. Eigenvectors (i.e. vectors of variable loadings) for the first two principal components for each water mass type.

Estuarine & Inner shelf Midshelf Slope

PC1 PC2 PC1 PC2 PC1 PC2 Cholorophyll a 0.1373 0.0372 0.3984 0.0239 0.3426 -0.1131 Diatom 0.0427 -0.2612 0.2789 -0.1377 0.4000 0.0887 Cryptophyte 0.2719 -0.1737 0.3078 -0.0681 0.0267 0.0135 Haptophyte -0.2331 -0.0142 -0.2523 -0.1752 -0.2026 -0.2525 Cyanobacteria -0.1519 0.3806 -0.2756 0.2617 -0.3257 0.2674 Prochlorophyte - - -0.1808 -0.0521 -0.3556 -0.0439 Salinity (S) -0.3717 -0.0536 -0.3116 -0.3208 -0.2504 -0.3306 Temperature (T) -0.1930 0.4019 -0.2826 0.2711 -0.1437 0.3788 NO3+NO2 0.3687 0.1544 0.2848 0.0980 0.3107 -0.0066 SiO3 0.4105 0.1589 0.3414 0.0491 -0.0492 0.1091 PO4 0.3108 0.1499 -0.1156 -0.1313 -0.1168 0.0424 NH4 0.2934 0.1723 0.0744 0.3147 0.2190 0.2746 Zm -0.0723 -0.2562 -0.0335 -0.3250 -0.2031 -0.3704 W-u 0.0832 -0.0668 -0.0573 0.3885 0.3362 -0.2105 W-v -0.1170 0.3485 0.2406 0.1981 0.0647 0.3815 Nf 0.3175 0.1035 0.1224 0.3594 -0.2024 0.3446 C-u -0.1073 0.4601 -0.1578 0.3869 -0.0755 0.1970 C-v 0.1225 -0.3204 0.0285 -0.1552 0.0092 -0.1252

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phytoplankton community structure in the river-influenced

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