Figure 1
Location of study sites. The inset shows location of Lake Resko Przymorskie
Table 1
Classification merging salinity and chlorides content used in this study (after Van Dam et al. 1994)
| Class | Description | Cl- (mg l-1) | Salinity (PSU) |
|---|---|---|---|
| 1 | fresh | < 100 | <0.2 |
| 2 | fresh-brackish | < 500 | < 0.9 |
| 3 | brackish-fresh | 500-1000 | 0.9-1.8 |
| 4 | brackish | 1000-5000 | 1.8-9.0 |
Table 2
Average, maximum and minimum values of water quality variables recorded during sampling events
| Season | Temp | Salinity | DO | pH | NH4+ | NO3- | PO43- | Ptot | cl- |
|---|---|---|---|---|---|---|---|---|---|
| (°C) | (PSU) | (ppm) | (mg l-1) | (mg l-1) | (Mg l-1) | µgl-1 | (Mg l-1) | ||
| 09.2012 | 14.9 | 3.5 | 10.4 | 8.4 | 0.6 | n.d. | 0.05 | 55.4 | 2495 |
| (14.4 - 15.3) | (3.0-3.7) | (6.6-12.4) | (7.7-8.7) | (0.5-0.7) | (0.0-0.1) | (42.0-78.0) | (2049-2686) | ||
| 05.2013 | 17.8 | 1.9 | n.a. | 9.0 | 0.3 | 2.5 | 0.1 | 42.3 | 1401 |
| (17.0 - 19.2) | (1.9-2.0) | (8.9-9.1) | (0.3-0.4) | (2.0-2.9) | (0.1-0.1) | (36.0-52.0) | (1328-1451) | ||
| 07.2013 | 21.3 | 2.5 | 9.4 | 9.1 | 0.3 | n.d. | n.d. | 67.8 | 2158 |
| (21.0-21.4) | (2.4-2.5) | (8.8-10.5) | (9.0-9.2) | (0.3-0.3) | (55.0-82.0) | (2123-2195) | |||
| 09.2013 | 14.2 | 3.4 | 11.1 | 9.2 | 0.6 | n.d. | 0.1 | 76.0 | 2687 |
| (14.1-14.2) | (3.3-3.5) | (10.2-12.4) | (9.2-9.3) | (0.5-0.7) | (0.1-0.1) | (65.0-85.0) | (2541-2812) | ||
| 11.2013 | 3.2 | 4.8 | 13.0 | 9.9 | 0.4 | n.d. | 0.1 | 35.0 | 3160 |
| (3.2-3.2) | (4.7-4.8) | (12.1-13.9) | (9.8-9.9) | (0.3-0.4) | (0.1-0.1) | (34.0-36.0) | (3090-3231) | ||
| 05.2014 | 21.3 | 3.6 | 11.3 | 8.5 | 0.6 | n.d. | n.d. | 31.0 | 2208 |
| (21.3-21.3) | (3.6-3.6) | (11.3-11.3) | (8.5-8.5) | (0.6-0.6) | (31.0-31.0) | (2208-2208) | |||
| 07.2014 | 24.1 | 3.1 | 8.2 | 9.5 | 1.1 | n.d. | 0.1 | 65.0 | 2306 |
| (23.7-24.4) | (3.0-3.1) | (7.2-9.1) | (9.4-9.5) | (1.0-1.1) | (0.1-0.1) | (54.0-76.0) | (2234-2378) |
n.a. - not analised; n.d. - not detected
Figure 2
Relative abundance of ecological groups of diatoms from September 2012 to July 2014
Figure 3
Relative abundance of dominant species in Lake Resko Przymorskie (species with values >2%)
Figure 4
Biplots of redundancy analysis (RDA): chemical and physical variables (Temp, NO3-, NH4+, Ptot, PO43-, pH, Cl-, salinity, DO) and diatom species (species with values > 2% of relative abundance). Statistically significant variables are marked in bold. Code used for species: ANMN – Actinocyclus normanii, AINA – Amphora inariensis, ALIB – Amphora libyca, AOVA – Amphora ovalis, APED – Amphora pediculus, AUGR – Aulacoseira granulata, CAMP – Caloneis amphisbaena, CATO – Cyclotella atomus, CCMS – Cyclotella comensis, CMEN – Cyclotella meneghiniana, CPLI – Cocconeis placentula var. lineata, CVSO – Cavinula scuttelloides, DITE – Diatoma tenius, EARE – Ellerbeckia arenaria, FBER – Belonastrum berolinensis, FBRE – Pseudostaurosira brevistriata, FGEO – Pseudostaurosiropsis geocollegarum, FIIS – Fragilaria inflata var. istvanffyi, FMAR – Martyana martyi, FNAN – Fragilaria nanana, FPIN – Staurosirella pinnata, FSOP – Fragilaria sopotensis, FSSA – Pseudostaurosira subsalina, HHUN – Hippodonta hungarica, KCLE – Karayevia clevei, NCIN – Navicula cincta, NPLT – Placoneis placentula, NRAD – Navicula radiosa, NRHY – Navicula rhynchocephala, NTPT – Navicula tripunctata, NVUL – Navicula vulpina, OMUT – Opephora olsenii, RAAB – Rhoicosphenia abbreviata, SCON – Staurosira construens, SMED – Stephanodiscus medius, SPAV – Stephanodiscus parvus
Table 3
Results of the forward selection of environmental parameters (Monte Carlo permutation test in RDA, p<0.05 are statistically significant and given in bold)
| Variable | λ | F | p |
|---|---|---|---|
| Temperature | 0.11 | 2.39 | 0.032 |
| pH | 0.12 | 2.70 | 0.015 |
| PO43- | 0.08 | 2.06 | 0.047 |
| Salinity | 0.06 | 1.46 | 0.155 |
| Cl- | 0.08 | 2.09 | 0.037 |
| DO | 0.04 | 1.18 | 0.308 |
| Ptot | 0.04 | 1.16 | 0.295 |
| NO3- | 0.03 | 0.92 | 0.490 |
| NH4+ | 0.03 | 0.98 | 0.434 |
Figure 5
Samples with respect to the chemical and physical water parameters (Temp, NO3-, NH4+, Ptot, PO43-, pH, Cl-, salinity, DO). Statistically significant variables are marked in bold.
Table 4
Optimum (weighted average) and tolerance (SD) of particular species compared to Cl- gradient
| Species | Abundance | Cl- mg l-1 | |||
|---|---|---|---|---|---|
| frequency | mean | SD | Optimum | Tolerance | |
| Epithemia turgida (Ehrenberg) Kützing | 2 | 0.0 | 0.1 | 2960.9 | 384.9 |
| Staurosira binodis (Ehrenberg) Lange-Bertalot | 2 | 0.0 | 0.1 | 2749.1 | 324.2 |
| Encymoena silesiacum (Bleisch) D.G.Mann | 2 | 0.0 | 0.1 | 2648.7 | 835.2 |
| Amphora marina W.Smith | 2 | 0.0 | 0.1 | 2638.9 | 1159.3 |
| Fragilaria capucina var. mesolepta (Rabenhorst) Rabenhorst | 2 | 0.0 | 0.1 | 2495.1 | 1159.3 |
| Navicula tripunctata (O.F.Müller) Bory | 3 | 0.1 | 0.2 | 2473.7 | 380.2 |
| Amphora ovalis (Kützing) Kützing | 3 | 0.1 | 0.1 | 2472.6 | 505.7 |
| Amphora pediculus (Kützing) Grunow ex A.Schmidt | 12 | 0.7 | 0.6 | 2459.1 | 618.3 |
| Cyclotella meneghiniana Kützing | 12 | 4.5 | 3.8 | 2457.3 | 391.5 |
| Pseudostaurosira brevistriata (Grunow) D.M.Williams & Round | 11 | 6.3 | 5.9 | 2414.3 | 630.2 |
| Staurosirella pinnata (Ehrenberg) D.M. Wiliams & Round | 4 | 0.5 | 1.0 | 2386.1 | 535.0 |
| Staurosira construens Ehrenberg | 20 | 24.5 | 6.1 | 2385.6 | 497.9 |
| Caloneis amphisbaena (Bory) Cleve | 5 | 0.1 | 0.1 | 2379.5 | 466.5 |
| Martyana martyi (Héribaud-Joseph) Round | 13 | 0.3 | 0.2 | 2371.0 | 609.1 |
| Pseudostaurosira subsalina (Hustedt) E.A.Morales | 9 | 1.2 | 1.5 | 2368.9 | 691.5 |
| Cavinula scuttelloides (W. Smith) Lange-Bertalot | 4 | 0.0 | 0.1 | 2356.3 | 308.3 |
| Pseudostaurosiropsis geocollegarum (Witkowski) E.A.Morales | 20 | 49.6 | 12.8 | 2347.8 | 505.0 |
| Navicula vulpina Kützing | 4 | 0.0 | 0.1 | 2313.7 | 259.6 |
| Aulacoseira granulata (Ehrenberg) Simonsen | 4 | 0.1 | 0.2 | 2311.1 | 310.3 |
| Karayevia clevei (Grunow) Round & Bukhtiyarova | 10 | 0.2 | 0.3 | 2310.3 | 656.3 |
| Fragilaria inflata var. istvanffyi (Pant.) Hustedt | 4 | 0.0 | 0.1 | 2305.1 | 686.4 |
| Cocconeis placentula var. lineata (Ehrenberg) Van Heurck | 6 | 0.4 | 0.6 | 2290.1 | 576.6 |
| Entomoneis alata (Ehrenberg) Ehrenberg | 2 | 0.0 | 0.1 | 2282.4 | 102.0 |
| Amphora inariensis Krammer | 6 | 0.1 | 0.2 | 2281.2 | 395.3 |
| Belonastrum berolinensis (Lemmermann) Round & Maidana | 4 | 0.1 | 0.1 | 2273.6 | 245.3 |
| Stephanodiscus medius Håkansson | 3 | 0.3 | 0.7 | 2261.3 | 143.0 |
| Fragilaria sopotensis Witkowski & Lange-Bertalot | 3 | 0.5 | 1.1 | 2245.5 | 102.9 |
| Lindavia comensis (Grunow) T.Nakov et al. | 2 | 0.5 | 1.4 | 2243.3 | 517.1 |
| Placoneis placentula (Ehrenberg) Mereschkowsky | 3 | 0.0 | 0.1 | 2212.3 | 964.0 |
| Navicula rhynchocephala Kützing | 4 | 0.1 | 0.3 | 2211.7 | 805.6 |
| Cyclotella atomus Hustedt | 4 | 4.9 | 9.9 | 2186.6 | 174.1 |
| Rhoicosphenia abbreviata (C.Agardh) Lange-Bertalot | 4 | 0.1 | 0.1 | 2156.4 | 854.0 |
| Navicula radiosa Kützing | 3 | 0.0 | 0.1 | 2128.5 | 519.8 |
| Diatoma tenuis C.Agardh | 1 | 1.1 | 4.4 | 2091.3 | 560.3 |
| Stephanodiscus parvus Stoermer & Håkansson | 3 | 0.4 | 1.0 | 2077.8 | 364.1 |
| Ellerbeckia arenaria (G.Moore ex Ralfs) R.M.Crawford | 4 | 0.1 | 0.1 | 2059.5 | 514.4 |
| Planothidium lanceolatum (Kützing) Round & Bukhtiyarova | 2 | 0.0 | 0.1 | 2041.9 | 1014.5 |
| Navicula cryptocephala Kützing | 2 | 0.0 | 0.1 | 2038.6 | 869.5 |
| Fragilaria nanana Lange-Bertalot | 4 | 0.2 | 0.4 | 2006.3 | 349.2 |
| Actinocyclus normanii (W.Gregory ex Greville) Hustedt | 7 | 0.2 | 0.2 | 1944.8 | 658.2 |
| Hippodonta hungarica (Grunow) Lange-Bertalot, Metzeltin Planothidium Witkowski | 5 | 0.7 | 1.3 | 1921.9 | 643.2 |
| Navicula menisculus Schumann | 2 | 0.0 | 0.1 | 1906.9 | 613.3 |
| Gomphonema olivaceum (Hornemann) Brébisson | 2 | 0.0 | 0.1 | 1896.3 | 799.0 |
| Amphora libyca Ehrenberg | 4 | 0.3 | 0.7 | 1844.8 | 684.7 |
| Opephora olsenii M⊘ller | 3 | 0.5 | 1.3 | 1780.2 | 769.0 |
| Navicula cincta (Ehrenberg) Ralfs | 3 | 0.0 | 0.1 | 1748.6 | 633.4 |
| Chaetoceros species | 2 | 0.0 | 0.1 | 1742.2 | 596.6 |
| Parlibellus crucicula (W.Smith) Witkowski, Lange-Bertalot & Metzeltin | 1 | 0.1 | 0.3 | 1556.1 | 799.0 |
| Planothidium delicatulum (Kützing) Round & Bukhtiyarova | 2 | 0.1 | 0.3 | 1470.7 | 799.0 |