Colonization of glacier foreland soils with entomopathogenic fungi
Abstract: Since mid of the 19th century the Alpine glaciers are retreating continuously. The"Rotmoos" valley glacier foreland (Tyrolean Central Alps) is 2km long with a chronosequence ofdevelopmental stages from recently deglaciated terrain to sites which have been ice-free for 145years at the terminal moraine dated 1858. Due to the gradual retreat of the glaciers we can nowobserve all age stages of community assembly within a limited spatial scale. Suchchronosequences represent natural experiments showing the sensitivity and the resilience ofalpine ecosystems exposed to changing environmental conditions. In this study the colonizationof entomopathogenic fungi in young soils was investigated. Soil samples were taken in springsummer and autumn at eleven sites at the glacier foreland. The abundance and density ofentomopathogenic fungi in soil were determined. Fungal isolates were identifiedmorphologically. Entomopathogenic fungi (Beauveria bassiana, Isaria farinosa, Hirsutella sp.,Syngliocladium sp., the anamorph of Cordyceps militaris) as well as fungi recognized as weakentomopathogens (Paecilomyces carneus and P. marquandii) could be detected along thechronosequence. In the first years after deglaciation, soils are sporadically “contaminated” withanemochorically distributed entomopathogenic fungi. In fifty year old soils entomopathogens arefrequent and diverse, similar to their possible hosts (collembolans, larvae of midges, mites etc.),that can be found in higher abundances at older soils.