Phippsia concinna in Sweden : Exploring ecological dependencies in a regionally endangered plant species that occurs in alpine snowbeds

Abstract:

The purpose of this study is to 1: Get an updated population estimate for the regionally endangered alpine specialist plant Phippsia concinna in Sweden and 2: Explore the ecological dependencies that limits the distributions of this species to late melt-out alpine snowbeds on calcareous soils, and 3: Explore if climate change in the southern part of the Scandes mountain range is causing a decline in the population numbers of P. concinna. The majority of the sites in Sweden where P. concinna occurred historically was inventoried in 1992. This study presents the results of a re-inventory of the same snowbeds after 22 years, along with measurements of abiotic soil factors and records of abundance and composition of associated vegetation at the sites. The main findings are 1: Population number of P. concinna has increased but one third of the original populations has disappeared since 1992, and 2: Soil pH appears to limit the distributions of P. concinna while slope aspect and soil Nitrogen concentrations affects this species competitive abilitiesin the Swedish Scandes. 3: Presence of P. concinna is negatively correlated to cover of other graminoids and bryophytes. These results suggests that snowbeds are melting earlier following increased temperatures and precipitations in summer, resulting in longer vegetation periods that favours plant species with stronger competitive abilities over specialised snowbed species. The observed rate of change in P. concinna populations during 22 years is evidence of fast occurring vegetation changes and highlights the need to monitor rare plant species in alpine environments.