Table 3
Linear regression models explaining the abundance of the two dominant species Dolichospermum flos-aquae and Microcystis aeruginosa, and MC-LR concentration in the Foum-Gleita Reservoir (Mauritania). The models result from a forward stepwise selection procedure and explain M. aeruginosa and D. flos-aquae biovolume (log MycBiov and log DolBiov in mm3 L−1) and Microcystin-LR concentration (log [MC-LR] in μg L−1) by the independent variables: dissolved inorganic nitrogen (log DIN in mg L−1), total phosphorus (log TP in mg L−1), and iron (log Fe in mg L−1), and surface water temperature (T in °C) and pH. All regression models were significant (p < 0.0001). The significance of the regression coefficients is indicated by * (0.01 < p < 0.05), ** (0.001 < p < 0.01), and *** (p < 0.001). Number of observations = 36.
N0 | Dependent variables | Independent variables | Linear model equations | R 2adj | F |
---|---|---|---|---|---|
1 | log DolBiov | log DIN | – 3.356*** + 3.363*log DIN | 0.182 | 4.894 |
2 | log DIN + log TP | – 3.723*** + 4.405*log DIN − 1.676***log TP | 0.193 | 9.364 | |
3 | log DIN + log TP + T | – 2.983** + 4.394*log DIN − 1.917***log TP − 0.03*T | 0.160 | 3.218 | |
4 | log DIN + log TP + pH | – 3.719** + 2.967*log DIN − 17.646**log TP − 1.457**pH | 0.430 | 9.794 | |
5 | log DIN + log TP + pH+ log Fe | – 3.027** + 2.631*log DIN − 12.628**log TP − 0.878*pH + 0.015*log Fe | 0.489 | 9.724 | |
6 | log MycBiov | log DIN | + 0.775*** − 3.317**log DIN | 0.863 | 111.396 |
7 | log DIN + log TP | + 1.614** − 1.355**log DIN + 3.831*log TP | 0.650 | 66.134 | |
8 | log DIN + log TP + T | + 2.789*** − 1.389**log DIN + 4.197*log TP − 0.038**T | 0.883 | 89.095 | |
9 | log DIN + log TP + T + pH | + 2.823*** − 1.549**log DIN + 4.273*log TP − 0.078*T + 0.238*pH | 0.884 | 67.469 | |
10 | log DIN + log TP + T + log Fe | + 2.917*** − 1.942**log DIN + 4.722*log TP − 0.206*T − 0.160***log Fe | 0.902 | 72.470 | |
11 | log [MC-LR] | log DIN | – 1.134** + 0.658**log DIN | 0.723 | 92.35 |
12 | log DIN + log TP | – 1.233** + 0.425**log DIN − 0.454**log TP | 0.803 | 72.252 | |
13 | log DIN + log TP + T | – 1.565*** + 0.415**log DIN − 0.346**log TP + 0.014**T | 0.856 | 70.30 | |
14 | log DIN + log TP + T + pH | – 1.257** + 0.390**log DIN − 0.334**log TP + 0.014**T − 0,038*pH | 0.854 | 52.341 | |
15 | log DIN + log TP + T + log Fe | – 1.324** + 0.312*log DIN − 0.590*log TP + 0.007**T + 0.019***log Fe | 0.909 | 55.150 |
Current usage metrics show cumulative count of Article Views (full-text article views including HTML views, PDF and ePub downloads, according to the available data) and Abstracts Views on Vision4Press platform.
Data correspond to usage on the plateform after 2015. The current usage metrics is available 48-96 hours after online publication and is updated daily on week days.
Initial download of the metrics may take a while.