Key abiotic parameters for the management of the richness of bryolichenic communities in bogs of North Patagonia (Chile)

Abstract

Peatlands are ecosystems that play a special role in conserving biodiversity because they are refugia for unusual wetland-dependent species. Nevertheless, these ecosystems are threatened in southern South America by the overharvesting of Sphagnum moss, used in horticulture as substrate. Moreover, the biodiversity measurement as species richness has not been considered in management practices. Thus, our purpose was to study the bryophyte and lichen diversity and abiotic factors of Chiloé peatlands to distinguish habitat preferences and key abiotic factors to improve peatland management. The study was conducted in eight peatlands of Chiloé Island in Chile (42-43° S and 75-73° W). We found good predictors to overall species richness and each organism group. The observed patterns of cryptogamic species richness are well explained by microtopographic variables and moisture, increasing in tree base, and decreasing in saturated substrate and carpet. We highly recommend conserving "tree base" microtopographic areas as reservoirs of species richness in intervened areas by harvesting. Furthermore, we also suggest monitoring water chemistry variables such as pH or ionic ratio (IR), to provide information to predict impacts on the biodiversity of peatlands under Sphagnum harvesting. These recommendations give rise to sustainable management and to transforming moss into a renewable resource for farmers.