Vanishing permanent glaciers: climate change is threatening a European Union habitat (Code 8340) and its poorly known biodiversity

Abstract

The cryosphere (i.e. glaciers and permafrost) and its related landforms offer a wide range of ecosystem services, thus they have strong relationships with human population. Even if these harsh environments have often been regarded as inhospitable, there is a growing amount of literature on glacial biodiversity, specifically concerning European mountains. Glaciers and permafrost-related landforms (e.g. rock glaciers) host a variety of cold-adapted taxa, from bacteria to vertebrates. They have been included in the Natura 2000 network, specifically in the habitat type: Permanent Glaciers (code 8340), but their biodiversity is still poorly known. Even if local extinctions and population reductions of cold-adapted species due to glacier and permafrost shrinking have been already documented, none of the species living in this habitat type are listed in the Habitat Directive Annexes. With this commentary, we call for urgent actions for an ecological characterization of this habitat type in order to plan monitoring and management of the biodiversity hosted by them. An increased knowledge of this no longer permanent habitat appears particularly urgent, because it is not replaceable and is likely to go extinct in the next decades.

Desoria calderonis sp. nov., a new species of alpine cryophilic springtail (Collembola: Isotomidae) from the Apennines (Italy), with phylogenetic and ecological considerations

“…These organisms appear to be differentiated among isolated glacial areas (Deharveng 1975;Lauga-Reyrel & Lauga 1995). By comparing different European glacier forelands, Hågvar et al (2020) observed how the species belonging to this group, and to a few other pioneer genera, are important not only as components of supraglacial communities (see also Gobbi et al 2021), but also as early colonisers of recently-deglaciated terrains. High diversity of cryophilic Isotomidae was observed in southern Alaska and in the Canadian Rocky Mountains in North America (Fjellberg 2010).…”

“…Among these cold-adapted species, Desoria and taxonomically related genera like Agrenia Börner, 1906, Gnathisotoma, Myopia andKaylathalia Stevens &D'Haese, 2016 (Najt 1981;Fjellberg 2010;Stevens & D'Haese 2017) include cryophilic species (Potapov 2001;Fjellberg 2007Fjellberg , 2010. Cryophilic species, in particular, are of great interest because they are particularly threatened by the current global warming and are good candidates as indicators for conservation projects aimed at investigating refugial glaciated areas (Gobbi et al 2021).…”

The need for stewardship of lands exposed by deglaciation from climate change

“…Glaciers, permafrost, and recently deglaciated areas are ecosystems in their own right and provide permanent or temporary habitat for a variety of specialized taxa from bacteria to vertebrates (Ficetola, 2021;Gobbi et al, 2021). The loss of mountain cryosphere-glacier and permafrost-and changes of the physiognomy of the emerging proglacial landscape threaten local high alpine biodiversity and ecosystems, such as altered hydrological, thermal and bio-geochemical cycles, glacier-fed streams, and glacier forelands (Brighenti et al, 2019).…”

“…The "winners" are more generalist and competitive species that benefit from the higher temperatures and colonize from lower elevations. Expected long-term effects include the loss of high alpine biodiversity, especially for the cold adapted taxa and high elevation endemic floras (Cuesta et al, 2020;Gobbi et al, 2021). These expected biological extinctions within proglacial systems will lead to ecological cascading effects on aquatic and terrestrial systems (Cauvy-Fraunié et al, 2016).…”

“…Organisms can colonize ice-free areas rapidly, and in less than a century, even forests and wetland ecosystems can develop in these former glacier and permafrost lands. These new geosystems and ecosystems might contribute to key environmental services such as water amount and quality, aquifer recharge, carbon sequestration, biomass production, and biodiversity (Gobbi et al, 2021). And there are many studies on the implications of glacier retreat for the corresponding landscapes, downstream ecosystems, and water supplies (e.g., The Special Reports on Global Warming [Cuesta et al, 2019;Hock, Bliss, et al, 2019;IPCC, 2018IPCC, , 2019).…”