Succession of arbuscular mycorrhizal fungi in a deflation hollow of the Słowiński National Park, Poland

Abstract

In the years 1994-1995, the occurrence of arbuscular mycorrhizal fungi (AMF) and arbuscular mycorrhizae (AM) in eight successional stages of vegetation of a deflation hollow no. 12 of the Łeba Bar, Poland, was investigated. Early successional stages were colonized by members of the families Gramineae and Juncaceae, being gradually replaced by ericaceous plants in the middle and later stages and by trees in the most advanced stage corresponding to the Empetro nigri-Pinetum plant association. From the 96 soil samples collected, 21 species in three genera of AMF were recovered. The fungi most frequently found were members of the genus Acaulospora. The overall spore abundance, the species_ richness of AMF and the level of AM colonisation increased from stage 1 to reach a maximum in the middle stages and then gradually declined, being lowest in the forested stage 8. The values of the overall spore abundance and those of the abundances of the most frequently occurring AMF species strongly evidenced functioning in nature of the process of host-dependent differentiation of AMF communities. Of the five most numerously represented AMF species, the early colonizer and quickly diminishing in later successional stages was Glomus 107. The mid-late successor was A. koskei, and the latest - Glomus aggregatum. All measures of AMF presence negatively correlated with the content of organic C in the soil and most of them were negatively correlated with soil N-NO3 and P concentrations. In contrast, the occurrence of AMY and AM generally was positively correlated with soil pH and the K content of the soil.