Average Niche Breadths of Species in Lake Macrophyte Communities Respond to Ecological

Average niche breadths of species in lake macrophyte communities respond to ecological gradients variably in four regions on two continents

Janne Alahuhta1*,2, Antti Virtala1, Jan Hjort1, Frauke Ecke3,4, Lucinda B. Johnson5, Laura Sass6, Jani Heino7

Online Resource

Oecologia

1 University of Oulu, Department of Geography, P.O. Box 3000, FI-90014 Oulu, Finland

2 Finnish Environment Institute, Freshwater Centre, P.O. Box 413, FI-90014 Oulu, Finland

3 Department of Aquatic Sciences and Assessment, Swedish University of Agricultural Sciences (SLU), P.O. Box 7050, SE-750 07 Uppsala, Sweden

4 Department of Wildlife, Fish and Environmental Studies, Swedish University of Agricultural Sciences (SLU), SE-901 83 Umeå, Sweden

5 University of Minnesota Duluth, Natural Resources Research Institute, 5013 Miller Trunk Highway, Duluth, MN 55811, USA

6 Illinois Natural History Survey, Prairie Research Institute, University of Illinois, 1816 South Oak Street, Champaign, IL 61820, USA

7 Finnish Environment Institute, Natural Environment Centre, Biodiversity, Paavo Havaksen Tie 3, FI-90570, Oulu, Finland

*Correspondence: Janne Alahuhta, University of Oulu, Department of Geography, P.O. Box 3000, FI-90014, University of Oulu, Finland.

Online Resource 1. Variation in the climate and water quality used to construct average niche breadths and explanatory variables within each study area. Descriptive statistics of latitude and longitude were not given.

Finland / Sweden / Minnesota / Wisconsin
Climate variables / Mean / Min. / Max. / SD / Mean / Min. / Max. / SD / Mean / Min. / Max. / SD / Mean / Min. / Max. / SD
Annual temperature (°C) / 2.77 / -0.24 / 4.83 / 1.15 / 3.83 / -1.44 / 7.88 / 2.84 / 5.64 / 2.50 / 7.27 / 1.28 / 5.91 / 3.85 / 8.23 / 1.71
Min. temperature (°C) / -13.24 / -17.92 / -9.40 / 1.97 / 3.83 / -10.22 / -19.63 / -2.49 / -18.57 / -23.20 / -15.72 / 1.86 / -15.99 / -20.18 / -11.95 / 2.79
Max. temperature (°C) / 20.83 / 19.24 / 21.53 / 0.50 / 19.75 / 14.51 / 21.89 / 1.66 / 27.88 / 22.37 / 29.10 / 1.29 / 26.93 / 25.30 / 28.70 / 1.15
Water quality variables
Alkalinity (mmol l-1) / 0.23 / 0.02 / 0.89 / 0.19 / 0.47 / 0.01 / 2.83 / 0.71 / 1.33 / 0.15 / 2.36 / 0.49 / 0.85 / 0.03 / 2.02 / 0.62
Color (mg Pt l-1) / 92.70 / 10.00 / 255.00 / 58.19 / 56.64 / 2.50 / 151.50 / 42.33 / 21.60 / 3.50 / 93.75 / 16.99 / 10.63 / 5.00 / 30.00 / 6.51
Total phosphorus (mg l -1) / 28.33 / 4.00 / 120.00 / 28.38 / 15.14 / 1.04 / 68.00 / 16.46 / 101.94 / 8.14 / 429.78 / 95.24 / 20.00 / 10.00 / 140.00 / 20.00
Explanatory variables
Altitude (m.a.s.l.) / 105.32 / 31.9 / 228.9 / 44.87 / 204.34 / 3.00 / 746.00 / 178.31 / 343.42 / 251.83 / 529.27 / 62.81 / 365.59 / 239.00 / 503.00 / 109.24
Lake Area (km2) / 6.16 / 0.43 / 38.82 / 8.56 / 3.16 / 0.04 / 51.7 / 7.49 / 2.73 / 0.21 / 11.52 / 2.86 / 0.5547 / 0.2027 / 1.3642 / 0.2949
Species richness / 28.26 / 12.00 / 42.00 / 7.94 / 12.16 / 4 / 23 / 4.73 / 12.4 / 2 / 27 / 6.39 / 18.67 / 6.00 / 40.00 / 6.79
Human impact (%) / 17.40 / 0.00 / 60.47 / 15.92 / 9.59 / 0 / 78.17 / 16.73 / 25.20 / 0 / 58.70 / 16.96 / 10.86 / 0.00 / 54.43 / 13.67

Online Resource 2. Bivariate correlations among the explanatory variables in each study region.

Finland / X / Y / Altitude / Area / Richness / Human
X / 1 / 0.4315 / 0.4872 / -0.3946 / -0.3768 / -0.4833
Y / 0.4315 / 1 / 0.6302 / -0.2021 / -0.1809 / -0.1412
Altitude / 0.4872 / 0.6302 / 1 / -0.377 / -0.5324 / -0.6061
Area / -0.3946 / -0.2021 / -0.377 / 1 / 0.3594 / 0.216
Richness / -0.3768 / -0.1809 / -0.5324 / 0.3594 / 1 / 0.5571
Human / -0.4833 / -0.1412 / -0.6061 / 0.216 / 0.5571 / 1
Sweden / X / Y / Altitude / Area / Richness / Human
X / 1 / 0.6448 / -0.0817 / 0.2068 / -0.0057 / -0.0851
Y / 0.6448 / 1 / 0.512 / 0.2331 / -0.1786 / -0.371
Altitude / -0.0817 / 0.512 / 1 / 0.1651 / -0.3822 / -0.5163
Area / 0.2068 / 0.2331 / 0.1651 / 1 / 0.0669 / 0.0873
Richness / -0.0057 / -0.1786 / -0.3822 / 0.0669 / 1 / 0.3913
Human / -0.0851 / -0.371 / -0.5163 / 0.0873 / 0.3913 / 1
Minnesota / X / Y / Altitude / Area / Richness / Human
X / 1 / 0.1689 / -0.4847 / -0.2404 / 0.2153 / -0.2306
Y / 0.1689 / 1 / 0.3614 / 0.1562 / 0.5902 / -0.6752
Altitude / -0.4847 / 0.3614 / 1 / 0.4597 / 0.0494 / -0.3635
Area / -0.2404 / 0.1562 / 0.4597 / 1 / 0.2114 / -0.5251
Richness / 0.2153 / 0.5902 / 0.0494 / 0.2114 / 1 / -0.5327
Human / -0.2306 / -0.6752 / -0.3635 / -0.5251 / -0.5327 / 1
Wisconsin / X / Y / Altitude / Area / Richness / Human
X / 1 / -0.7292 / -0.517 / -0.3967 / -0.337 / 0.7484
Y / -0.7292 / 1 / 0.7795 / 0.2589 / 0.3463 / -0.691
Altitude / -0.517 / 0.7795 / 1 / 0.1025 / 0.5125 / -0.6603
Area / -0.3967 / 0.2589 / 0.1025 / 1 / 0.1001 / -0.2419
Richness / -0.337 / 0.3463 / 0.5125 / 0.1001 / 1 / -0.358
Human / 0.7484 / -0.691 / -0.6603 / -0.2419 / -0.358 / 1

Online Resource 3. Linear regression model coefficients for the best average niche breadth models based on AICc for each study region.

Finland: Average climate niche breadths

Human+Y
Estimate / Std. Error / t value / Pr(>|t|)
(Intercept) / -2.559e+00 / 1.229e+00 / -2.083 / 0.042868 *
Human / -4.355e-03 / 1.520e-03 / -2.864 / 0.006278 **
Y / 6.519e-07 / 1.766e-07 / 3.692 / 0.000589 ***

Finland: Average water quality niche breadths

Altitude+Area+Human+Richness
Estimate / Std. Error / t value / Pr(>|t|)
(Intercept) / 0.9030952 / 0.1089732 / 8.287 / 1.32e-10 ***
Altitude / -0.0010572 / 0.0004962 / -2.131 / 0.03862 *
Area / 0.0066497 / 0.0021262 / 3.128 / 0.00309 **
Human / 0.0068996 / 0.0012341 / 5.591 / 1.26e-06 ***
Richness / 0.0070321 / 0.0024993 / 2.814 / 0.00724 **
Area+Human+Richness+Y
(Intercept) / 2.245e+00 / 8.085e-01 / 2.777 / 0.007971 **
Area / 7.922e-03 / 1.959e-03 / 4.043 / 0.000204 ***
Human / 7.794e-03 / 1.152e-03 / 6.764 / 2.29e-08 ***
Richness / 8.292e-03 / 2.382e-03 / 3.482 / 0.001120 **
Y / -2.176e-07 / 1.142e-07 / -1.906 / 0.063054

Finland: Average climate-water quality niche breadths

X+Y
Estimate / Std. Error / t value / Pr(>|t|)
(Intercept) / 1.251e-02 / 1.060e+00 / 0.012 / 0.990633
X / -7.033e-07 / 2.364e-07 / -2.975 / 0.004615 **
Y / 6.022e-07 / 1.638e-07 / 3.676 / 0.000608 ***
Human+X+Y
(Intercept) / -3.457e-01 / 1.083e+00 / -0.319 / 0.751014
Human / 1.926e-03 / 1.413e-03 / 1.363 / 0.179568
X / -5.976e-07 / 2.468e-07 / -2.422 / 0.019451 *
Y / 5.961e-07 / 1.624e-07 / 3.670 / 0.000629 ***
Altitude+X+Y
(Intercept) / -1.303e+00 / 1.611e+00 / -0.809 / 0.422716
Altitude / -8.178e-04 / 7.551e-04 / -1.083 / 0.284466
X / -5.735e-07 / 2.647e-07 / -2.167 / 0.035456 *
Y / 7.390e-07 / 2.066e-07 / 3.576 / 0.000833 ***

Sweden: Average climate niche breadths

Altitude+Area+Human+Y
Estimate / Std. Error / t value / Pr(>|t|)
(Intercept) / -4.806e-01 / 6.073e-01 / -0.791 / 0.43293
Altitude / 1.016e-03 / 2.248e-04 / 4.520 / 4.45e-05 ***
Area / 1.049e-02 / 4.350e-03 / 2.411 / 0.02005 *
Human / -5.621e-03 / 2.020e-03 / -2.783 / 0.00785 **
Y / 2.404e-07 / 9.339e-08 / 2.574 / 0.01342 *

Sweden: Average water quality niche breadths

Altitude+Area+Human+Y
Estimate / Std. Error / t value / Pr(>|t|)
(Intercept) / 2.341e+00 / 6.575e-01 / 3.561 / 0.000887 ***
Altitude / -4.780e-04 / 2.434e-04 / -1.964 / 0.055724
Area / -8.090e-03 / 4.710e-03 / -1.718 / 0.092737
Human / 8.764e-03 / 2.187e-03 / 4.008 / 0.000228 ***
Y / -2.056e-07 / 1.011e-07 / -2.033 / 0.047963 *
Altitude+Human+Y
(Intercept) / 2.549e+00 / 6.598e-01 / 3.863 / 0.000349 ***
Altitude / -4.748e-04 / 2.485e-04 / -1.911 / 0.062282
Human / 8.984e-03 / 2.229e-03 / 4.031 / 0.000207 ***
Y / -2.404e-07 / 1.011e-07 / -2.377 / 0.021676 *
Area+Human+Y
(Intercept) / 2.950e+00 / 5.975e-01 / 4.937 / 1.08e-05 ***
Area / -8.018e-03 / 4.854e-03 / -1.652 / 0.105341
Human / 1.019e-02 / 2.125e-03 / 4.797 / 1.73e-05 ***
Y / -3.118e-07 / 8.803e-08 / -3.541 / 0.000924 ***
Area+Human+X+Y
(Intercept) / 2.957e+00 / 5.901e-01 / 5.012 / 8.85e-06 ***
Area / -7.908e-03 / 4.794e-03 / -1.650 / 0.105960
Human / 9.553e-03 / 2.143e-03 / 4.457 / 5.47e-05 ***
X / 4.754e-07 / 3.228e-07 / 1.473 / 0.147807
Y / -4.189e-07 / 1.134e-07 / -3.695 / 0.000593 ***
Altitude+Area+Human
(Intercept) / 1.0107448 / 0.0657901 / 15.363 / < 2e-16 ***
Altitude / -0.0007427 / 0.0002125 / -3.495 / 0.001062 **
Area / -0.0100092 / 0.0047687 / -2.099 / 0.041339 *
Human / 0.0083613 / 0.0022508 / 3.715 / 0.000549 ***
Altitude+Area+Human+X
(Intercept) / 1.588e+00 / 3.864e-01 / 4.111 / 0.000165 ***
Altitude / -7.732e-04 / 2.105e-04 / -3.672 / 0.000636 ***
Area / -8.924e-03 / 4.757e-03 / -1.876 / 0.067161
Human / 8.536e-03 / 2.223e-03 / 3.840 / 0.000382 ***
X / -3.776e-07 / 2.491e-07 / -1.516 / 0.136447
Human+Y
(Intercept) / 3.152e+00 / 5.955e-01 / 5.293 / 3.11e-06 ***
Human / 1.040e-02 / 2.160e-03 / 4.815 / 1.57e-05 ***
Y / -3.456e-07 / 8.719e-08 / -3.964 / 0.00025 ***

Sweden: Average climate-water quality niche breadths

Altitude+Human
Estimate / Std. Error / t value / Pr(>|t|)
(Intercept) / 1.0739514 / 0.0506840 / 21.189 / < 2e-16 ***
Altitude / 0.0004558 / 0.0001648 / 2.766 / 0.00808 **
Human / 0.0034287 / 0.0017561 / 1.952 / 0.05686
Altitude+Area+Human
(Intercept) / 1.0625905 / 0.0509093 / 20.872 / <2e-16 ***
Altitude / 0.0004288 / 0.0001645 / 2.607 / 0.0123 *
Area / 0.0050376 / 0.0036901 / 1.365 / 0.1788
Human / 0.0035269 / 0.0017417 / 2.025 / 0.0487 *
Altitude
(Intercept) / 1.1295558 / 0.0431363 / 26.186 / <2e-16 ***
Altitude / 0.0003445 / 0.0001591 / 2.166 / 0.0353 *

Minnesota: Average climate niche breadths

Human+Y
Estimate / Std. Error / t value / Pr(>|t|)
(Intercept) / -3.159231 / 2.699165 / -1.170 / 0.2477
Human / -0.009860 / 0.003713 / -2.655 / 0.0108 *
Y / 0.113192 / 0.057850 / 1.957 / 0.0563
Human
(Intercept) / 2.11949 / 0.08655 / 24.490 / < 2e-16 ***
Human / -0.01470 / 0.00285 / -5.158 / 4.7e-06 ***

Minnesota: Average water quality niche breadths

X
Estimate / Std. Error / t value / Pr(>|t|)
(Intercept) / 8.26207 / 2.16898 / 3.809 / 0.000396 ***
X / 0.07874 / 0.02306 / 3.414 / 0.001308 **
Richness+X
(Intercept) / 8.828601 / 2.192636 / 4.026 / 0.000205 ***
Richness / -0.005397 / 0.004034 / -1.338 / 0.187406
X / 0.084048 / 0.023214 / 3.621 / 0.000718 ***
Altitude+X
(Intercept) / 8.9452714 / 2.2622872 / 3.954 / 0.000257 ***
Altitude / 0.0004560 / 0.0004344 / 1.050 / 0.299153
X / 0.0876649 / 0.0245549 / 3.570 / 0.000835 ***
Altitude+Richness+X
(Intercept) / 9.6314515 / 2.2874276 / 4.211 / 0.000117 ***
Altitude / 0.0005080 / 0.0004311 / 1.178 / 0.244667
Richness / -0.0057952 / 0.0040318 / -1.437 / 0.157377
X / 0.0943862 / 0.0247273 / 3.817 / 0.000402 ***

Minnesota: Average climate-water quality niche breadths

Altitude+Human+X
Estimate / Std. Error / t value / Pr(>|t|)
(Intercept) / 7.8198370 / 3.4096592 / 2.293 / 0.02644 *
Altitude / 0.0015007 / 0.0006808 / 2.204 / 0.03255 *
Human / -0.0082914 / 0.0024496 / -3.385 / 0.00147 **
X / 0.0696406 / 0.0376242 / 1.851 / 0.07060
Human
(Intercept) / 1.861378 / 0.066027 / 28.191 / < 2e-16 ***
Human / -0.011314 / 0.002174 / -5.203 / 4.02e-06 ***
Altitude+Area+Human
(Intercept) / 1.4721542 / 0.2377848 / 6.191 / 1.50e-07 ***
Altitude / 0.0013561 / 0.0006714 / 2.020 / 0.0492 *
Area / -0.0247756 / 0.0158645 / -1.562 / 0.1252
Human / -0.0116614 / 0.0024272 / -4.805 / 1.69e-05 ***
Altitude+Human
(Intercept) / 1.5234816 / 0.2390803 / 6.372 / 7.34e-08 ***
Altitude / 0.0009029 / 0.0006146 / 1.469 / 0.148
Human / -0.0102096 / 0.0022761 / -4.486 / 4.67e-05 ***
Altitude+Area+Human+X
(Intercept) / 6.6293411 / 3.5821682 / 1.851 / 0.07079
Altitude / 0.0017127 / 0.0007082 / 2.419 / 0.01969 *
Area / -0.0175798 / 0.0164553 / -1.068 / 0.29107
Human / -0.0096732 / 0.0027667 / -3.496 / 0.00107 **
X / 0.0568760 / 0.0394208 / 1.443 / 0.15600
Human+Y
(Intercept) / -0.790314 / 2.106210 / -0.375 / 0.7092
Human / -0.008882 / 0.002898 / -3.065 / 0.0036 **
Y / 0.056861 / 0.045142 / 1.260 / 0.2140

Wisconsin: Average climate niche breadths

Richness+Y
Estimate / Std. Error / t value / Pr(>|t|)
(Intercept) / 10.328447 / 1.316435 / 7.846 / 5.00e-10 ***
Richness / 0.009704 / 0.006094 / 1.592 / 0.118
Y / -0.198077 / 0.030589 / -6.475 / 5.59e-08 ***
Human+Richness+Y
(Intercept) / 8.808812 / 1.641808 / 5.365 / 2.70e-06 ***
Human / 0.005332 / 0.003526 / 1.512 / 0.1374
Richness / 0.010810 / 0.006055 / 1.785 / 0.0809
Y / -0.165727 / 0.036984 / -4.481 / 5.06e-05 ***
Y
(Intercept) / 9.54354 / 1.24046 / 7.694 / 7.33e-10 ***
Y / -0.17639 / 0.02783 / -6.337 / 8.29e-08 ***
Human+Y
(Intercept) / 8.163861 / 1.639213 / 4.980 / 9.39e-06 ***
Human / 0.004572 / 0.003582 / 1.276 / 0.208260
Y / -0.146532 / 0.036218 / -4.046 / 0.000197 ***

Wisconsin: Average water quality niche breadths