Floristic diversity and spatial distribution of roadside halophytes along forest and field roads in Szczecin Lowland (West Poland)

The paper presents research results of roadside halophytes and soil salinity which were carried out along public roads with hardened surface within the forest and agricultural areas in Szczecin Lowland (W. Poland). Using ice-removing chemicals on road surfaces in winter causes growth of road shoulder soil salinity especially in early spring and favour settling roadsides by halophytes. In total 34 species of halophytes were stated from 10 families. Among them Asteraceae and Poaceae families were represented the most numerously by facultative halophytes like Dactylis glomerata L, Poa pratensis L. and Achillea millefolium L. Spatial distribution of roadside halophytes was related to different soil salinity (the range within forest roadsides: 0.035-0.321 g NaCl kg^-1 soil and field ones: 0.140-1.295 g NaCl kg^-1 soil) observed within zonal structure of roadside profile. The road shoulder soil salinity should be admitted to be raised, this however not qualifying them into category of saline soils. The highest salinity was detected in soil samples from the roadside edge adjoining directly the road surface. However most halophilous species were found in the zone of proper road shoulder, both on forest and field roads.