Phototrophic communities of Ahshtyrskaya Cave in the condition of artificial light

Abstract

Investigation presents the multiyear assessment of biodiversity and development features of phototrophic communities from hypogean habitats. Caves exploitation as a tourist sites leads to anthropogenic transformation of subterranean ecosystems and formation of new communities named lampenflora. An example is given by the Ahshtyrskaya Cave (Sochi, Russia), which was equipped in 2000. The air temperature in the cave was 9-18 °C, humidity average 60-80%, the content of 222Rn 250-550 Bk/m3. Species identification was performed using standard approaches and cultivation methods. Cluster analysis was used to estimate similarity of communities in different cave zones. Biodiversity of phototrophs was revealed in entrance zone and zone of artificial light in 2017-2019. Species Microcystis pulverea, Scytonema drilosiphon, Chlorella vulgaris, Eucladium verticillatum predominated in communities of abovementioned zones. Considering the entrance zone communities as climax ones, comparison them with lampenflora can help to determine the speed and direction of succession. As a result of cluster analysis, it was established that species composition of lampenflora is most close to the entrance zone in case of maximum illuminated area. Thus, the succession of lampenflora depends on the intensity of illumination and tends to the species composition of the entrance zone communities.