Evaluation of species inter-relationsand soil conditions in Arnica montana Lhabitats: a step towards active protectionof endangered and high-valued medicinalplant species in NE Poland

摘要

Arnica montana L. is a critically endangered and highly valued medicinal plant species in Europe. We show the inter-relationships between arnica and accompanyingplant species, as well as soil factors, that promote the persistence of the studied forest arnica populations in terms of active protection of this species in the northeastregion of Europe. Te population characteristics and plant species composition wereassessed during a feld study. Additionally, soil samples were taken and analyzedto assess variation in soil conditions in the habitats of arnica populations. Correlations between population characteristics and soil properties were highlighted. Teforest habitats of arnica presented in this study difer from those described in otherEuropean mountain and submountain areas. Te sandy and very poor soils arecharacterized by a very low content of macro- and microelements, and a strong acidreaction. Te positive correlation between population characteristics and Ca andK indicates an important role of these macroelements in fower head production.Acidity, K, Ca, the sum of exchangeable bases, and base saturation play crucial rolesin the persistence of arnica populations in pine forests. Te level of acidity and itsconsequences result from soil-forming processes and climatic conditions ratherthan air pollution. When planning active protection scenarios, special attentionshould be paid to the frequency and cover of Vaccinium myrtillus, which can act asa competitor in forest habitats. Assessment of soil conditions that favor the persistence of the studied arnica populations and species relationships is important forimproving knowledge of the ecology of the species and for the active protection ofendangered plant species.