Future emergence of new ecosystems caused by glacial retreat.

Glacier shrinkage and the development of post-glacial ecosystems related to anthropogenic climate change are some of the fastest ongoing ecosystem shifts, with marked ecological and societal cascading consequences1-6. Yet, no complete spatial analysis exists, to our knowledge, to quantify or anticipate this important changeover7,8. Here we show that by 2100, the decline of all glaciers outside the Antarctic and Greenland ice sheets may produce new terrestrial, marine and freshwater ecosystems over an area ranging from the size of Nepal (149,000 ± 55,000 km2) to that of Finland (339,000 ± 99,000 km2). Our analysis shows that the loss of glacier area will range from 22 ± 8% to 51 ± 15%, depending on the climate scenario. In deglaciated areas, the emerging ecosystems will be characterized by extreme to mild ecological conditions, offering refuge for cold-adapted species or favouring primary productivity and generalist species. Exploring the future of glacierized areas highlights the importance of glaciers and emerging post-glacial ecosystems in the face of climate change, biodiversity loss and freshwater scarcity. We find that less than half of glacial areas are located in protected areas. Echoing the recent United Nations resolution declaring 2025 as the International Year of Glaciers' Preservation9 and the Global Biodiversity Framework10, we emphasize the need to urgently and simultaneously enhance climate-change mitigation and the in situ protection of these ecosystems to secure their existence, functioning and values.

Glacier retreat reorganizes river habitats leaving refugia for Alpine invertebrate biodiversity poorly protected.

Alpine river biodiversity around the world is under threat from glacier retreat driven by rapid warming, yet our ability to predict the future distributions of specialist cold-water species is currently limited. Here we link future glacier projections, hydrological routing methods and species distribution models to quantify the changing influence of glaciers on population distributions of 15 alpine river invertebrate species across the entire European Alps, from 2020 to 2100. Glacial influence on rivers is projected to decrease steadily, with river networks expanding into higher elevations at a rate of 1% per decade. Species are projected to undergo upstream distribution shifts where glaciers persist but become functionally extinct where glaciers disappear completely. Several alpine catchments are predicted to offer climate refugia for cold-water specialists. However, present-day protected area networks provide relatively poor coverage of these future refugia, suggesting that alpine conservation strategies must change to accommodate the future effects of global warming.

Global CO2 emissions from dry inland waters share common drivers across ecosystems.

Many inland waters exhibit complete or partial desiccation, or have vanished due to global change, exposing sediments to the atmosphere. Yet, data on carbon dioxide (CO2) emissions from these sediments are too scarce to upscale emissions for global estimates or to understand their fundamental drivers. Here, we present the results of a global survey covering 196 dry inland waters across diverse ecosystem types and climate zones. We show that their CO2 emissions share fundamental drivers and constitute a substantial fraction of the carbon cycled by inland waters. CO2 emissions were consistent across ecosystem types and climate zones, with local characteristics explaining much of the variability. Accounting for such emissions increases global estimates of carbon emissions from inland waters by 6% (~0.12 Pg C y-1). Our results indicate that emissions from dry inland waters represent a significant and likely increasing component of the inland waters carbon cycle.

When the Ice Has Gone: Colonisation of Equatorial Glacier Forelands by Ground Beetles (Coleoptera: Carabidae).

Ground beetles (Coleoptera: Carabidae) are among the early colonisers of recently deglaciated terrains. While patterns of carabid colonisation along forelands of retreating glaciers have been thoroughly investigated in temperate climates, information remains scarce in tropical mountains. This study aimed to describe for the first time the carabid beetle species assemblages along the chronosequence of two tropical Andean glaciers (Antisana and Carihuairazo, Ecuador). Shannon index, taxonomic distinctness and species assemblage composition did not reveal deterministic and directional patterns. Only the principal coordinate analysis performed on the Antisana dataset showed that some species had a clear preference for terrains deglaciated for more than 200 years. Our results showed that equatorial glacier forelands are colonised by pioneer species that persist from the recently deglaciated terrains (less than 25 years) to terrains deglaciated since more than 200 years. This pattern fits the 'addition and persistence model' of high-latitude glacier forelands, rather than the 'species replacement model' of the Alps. The pioneer species observed are high-altitude specialists adapted to constantly cold environments, but not specifically ice-related. In the current context of climate warming, pioneer and cold-adapted species living near the glaciers of equatorial mountains are therefore only threatened by the 'summit trap' risk, unlike in temperate regions, as they are not strictly linked to the glacier microclimate.