Introduction 2006 1998 1993 2000 1993 1996 2002 2003 1998 Potamogeton pectinatus P. perfoliatus P. perfoliatus P. pectinatus 1 1986 P. pectinatus P. perfoliatus. Cygnus columbianus bewickii C. cygnus P. pectinatus 1998 2001 2002 2002 Fig. 1 Potamogeton perfoliatus P. pectinatus P. pectinatus  P. pectinatus P. perfoliatus P. pectinatus P. perfoliatus 1997 P. pectinatus P. perfoliatus 1992 P. pectinatus P. perfoliatus P. pectinatus P. perfoliatus P. perfoliatus 1991 2001 2002 P. perfoliatus P. pectinatus P. perfoliatus Potamogeton perfoliatus P. pectinatus Methods 2 2 2 P. pectinatus P. perfoliatus 2002 C. cygnus C. columbianus bewickii C. olor P. pectinatus P. perfoliatus 1986 1998 2002 Fulica atra Anas platyrhynchos Anas acuta Anas penelope Bucephala clangula Aythya fuligula Aythya ferina 1986 2002 Anser anser 1986 Fig. 2  Enlargement gray squares P. perfoliatus p Black squares P. perfoliatus \documentclass[12pt]{minimal}
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\begin{document}$$ \overline{P}, $$\end{document} P p  Statistica Results Vegetation and water depth mapping 3 Potamogeton pectinatus P. perfoliatus P. perfoliatus P. perfoliatus Fig. 3 vertical line upper map P. perfoliatus Grey P. perfoliatus middle map P. pectinatus.  lower map  Swans 4 2002 P. pectinatus 4 F 8,160 P F 32,160 P F 4,20 P Y 4 Fig. 4 upper panel 2 Cygnus cygnus C. columbianus bewickii C. olor lower panel  Transplant experiment P. perfoliatus \documentclass[12pt]{minimal}
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\begin{document}$$ \overline{P} $$\end{document} P P. perfoliatus 1 5 P. perfoliatus p P. perfoliatus Fig. 5 P. pectinatus P. perfoliatus \documentclass[12pt]{minimal}
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\begin{document}$$ \overline{P}, $$\end{document} P. perfoliatus P P. perfoliatus p  Table 1 Potamogeton perfoliatus P. pectinatus Source of variation Potamogeton F df P −2 P. pectinatus a 1,10 NS P. perfoliatus  a 1,10 NS P. pectinatus  b 2,15 NS −2 P. pectinatus a 1,10 NS P. perfoliatus a 1,10 NS P. pectinatus b 2,15 * −2 P. pectinatus a 1,10 NS P. pectinatus b 2,15 NS * P \documentclass[12pt]{minimal}
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\begin{document}$$ \overline{P} $$\end{document} P F 1,10 P Y F 1,10 P Y P. pectinatus P. perfoliatus \documentclass[12pt]{minimal}
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\begin{document}$$ \overline{P} $$\end{document}  P 5 2 P. perfoliatus P. pectinatus 5 2 Table 2 P. pectinatus P. perfoliatus P \documentclass[12pt]{minimal}
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\begin{document}$$ \overline{P} $$\end{document} Source of variation Potamogeton F df P n −2 P. pectinatus 1,10 *** n −2 P. perfoliatus 1,10 *** n −2 P. pectinatus 1,10 NS n −2 P. perfoliatus 1,10 *** P Y Discussion P. perfoliatus P. pectinatus P. perfoliatus P. perfoliatus P. pectinatus 1992 1997 P. perfoliatus P. perfoliatus 2001 P. pectinatus 1998 2002 P. pectinatus 1991 2001 P. perfoliatus P. pectinatus P. perfoliatus P. pectinatus 2007 2002 P. pectinatus P. perfoliatus Potamogeton perfoliatus P. perfoliatus P. perfoliatus P. perfoliatus P. pectinatus P 2003 2002 2004 P. perfoliatus P. pectinatus P. pectinatus 1986 2002 1998 P. perfoliatus P. pectinatus P. pectinatus P. perfoliatus P. perfoliatus P. pectinatus P. perfoliatus P. pectinatus P. pectinatus P. pectinatus 2003 P. pectinatus P. perfoliatus 1999 P. pectinatus 1999 P. pectinatus 2007 P. perfoliatus 2002 2004 P. pectinatus P. pectinatus 2001 1998