Alpine limnology of the Rocky Mountains of Canada and the USA in the context of environmental change

Abstract

The cumulative impacts of multiple environmental and anthropogenic stressors on freshwater biodiversity have been studied in systems across the globe. The magnitude of multiple interdependent stressors on alpine systems may lead to increased primary productivity and jeopardize these unique communities. In this review, the consequences of individual stressors on alpine lake and pond ecology are synthesized, as well as the cumulative and potentially synergistic or antagonistic effects of multiple stressors. Beside temperature variability, other stressors reviewed include ultra violet (UV) radiation, organic pollutants, nutrient deposition, and biological invasions. Each stressor was evaluated individually and in combination with increasing water temperatures. In alpine environments, climatic warming is anticipated to increase with elevation, therefore amplifying the effects of temperature-related responses. The purpose of this review is to highlight the ecological effects of climate change on alpine lakes and ponds in the Rocky Mountains of North America and fill knowledge gaps between disciplines of aquatic studies. This work underscores that to better understand and face the overall effects of climate change on alpine biota, investigations must continue to assess the compounded impacts of multiple stressors. Emphasis must be put on the standardization of monitoring methods across alpine regions to aid in consistent trend and prediction analysis within the context of both current and future climate change.

Climate change and the biodiversity of alpine ponds: Challenges and perspectives

“… Community composition: Studies were done on alpine ponds using principally taxonomic/phylogenetic diversity (42% of selected papers). Warming led to broad changes on species richness (Redmond, 2018 ; Sandvik & Odland, 2014 ). For example, no specialist species colonize alpine ponds when rare specialist species are disappearing (Sandvik & Odland, 2014 ).…”

“…For example, no specialist species colonize alpine ponds when rare specialist species are disappearing (Sandvik & Odland, 2014 ). But also, communities can shift to smaller body size species more adapted to warming conditions (Redmond, 2018 ).…”

“…Alpine biodiversity is already constrained by high‐altitude extreme conditions, such as radiation exposure and high winds. For example, many alpine species require pigmentation or aquatic lifestyles to protect them from high‐altitude UV‐B radiation, which increases by 19% per 1000 m of elevation (Blumthaler et al., 1992 ; Redmond, 2018 ). Likewise, flying species need to generate the required power and wing size to adapt to approximately 5% increase of airspeed per 1000 m increase in altitude and low air density (Hedenström et al., 2002 ).…”

“…Climate change will not affect all species equally, challenging our ability to predict overall biodiversity responses across alpine ponds. Indeed, certain species may even be favored under climate change due to the disappearance of ice barriers and competitors, or perhaps due to preferable changes in food webs (Cauvy‐Fraunié et al., 2016 ; Redmond, 2018 ; Seimon et al., 2007 ). Broadly however, warmer temperatures lead to expected changes in species phenology (e.g., early emergence), size and fecundity (Harper & Peckarsky, 2006 ), and geographical distribution (Lindholm et al., 2015 ; Pallarés et al., 2020 ).…”

Insights into the microbial autotrophic potential of a shallow oligotrophic alpine pond

“…Therefore, a better understanding of microbial primary production potential and dynamics is fundamental in order to develop a comprehensive view on the ecology of oligotrophic freshwater systems and to predict their potential response to perturbations. This is of great concern especially in fragile contexts such as alpine oligotrophic freshwater ecosystems, where the effects of climate change are expected to have strong impacts, for instance in terms of hydrological regime, water quality and trophic status (Beniston 2003;Slemmons et al 2013;Redmond 2018).…”