Inland halophilious vegetation as indicator of soil salinity

Research was done over the period of 1995-1998 in the industrial and natural saline areas of the Kujawy region, central Poland. The study area was located mainly in the vicinity of two soda factories. The investigation aimed at determination of halophytes' importance in indication of soil salinity. The main soil factors important for halophilous plant species distribution were concentration of Cl-, content of K+, SO42-, N-tot. in the soil, electrical conductivity (ECe) and pH. Their importance was identified after CCA, forward selection and Monte Carlo permutation test. Distribution analysis of fourteen species along a salinity gradient showed that only Salicornia europaea, Glaux maritima and Triglochin maritima could be used as indicators of soil salinity described by ECe. The main factors important for distribution of ten distinguished halophilous communities were ECe, moisture, content of SO42- and Ca2+/Na+ ratio (after discriminant analysis CVA, forward selection and Monte Carlo permutation test). Salicornia europaea community and Aster tripolium community were present at salinity over 20 mS/cm, Triglocbin maritima community over 12 mS/cm, Puccinellia distans-Salicornia europaea-Spergularia marina community over 8 mS/cm and Glaux maritima-Potentilla anserina-Agrostis stolonifera community over 2 mS/cm. Plant communities were better indicators of soil salinity than individual species.