Habitat conditions of the endangered species Salix myrtilloides in Eastern Poland

Abstract

Changes in habitat conditions in the area of Eastern Poland (Polesie Podlaskie), often associated with anthropopressure, cause a reduction in the number of locations and population size of valuable and rare bog plant species, including a Pleistocene boreal relict, Salix myrtilloides. The aim of this study was to determine the current conditions of occurrence of this species based on the physico-chemical parameters of peatland piezometric groundwater. The results confirm the declining trend in the number of locations and abundance of this species in the past few decades, but at the same time they confirm the wide range of amplitude of the many investigated factors. Among the groundwater parameters studied, the low level of nitrogen fractions, phosphorus fractions, cations, and DOC can be considered to be a set of conditions promoting the preservation of the Salix myrtilloides population. The higher concentrations of phosphates, sulfates, Na, Ca, and Mg as well as higher pH and electrolytic conductivity can be considered to be presum- ably unfavorable. The lack of significant differences in the values of the piezometric water factors investi - gated for the sites with different population sizes of the studied species requires the identification of other limiting factors and the implementation of programs for its active protection in Poland.