Synergistic interactions among growing stressors increase risk to an Arctic ecosystem

Abstract

Oceans provide critical ecosystem services, but are subject to a growing number of external pressures, including overfishing, pollution, habitat destruction, and climate change. Current models typically treat stressors on species and ecosystems independently, though in reality, stressors often interact in ways that are not well understood. Here, we use a network interaction model (OSIRIS) to explicitly study stressor interactions in the Chukchi Sea (Arctic Ocean) due to its extensive climate-driven loss of sea ice and accelerated growth of other stressors, including shipping and oil exploration. The model includes numerous trophic levels ranging from phytoplankton to polar bears. We find that climate-related stressors have a larger impact on animal populations than do acute stressors like increased shipping and subsistence harvesting. In particular, organisms with a strong temperature-growth rate relationship show the greatest changes in biomass as interaction strength increased, but also exhibit the greatest variability. Neglecting interactions between stressors vastly underestimates the risk of population crashes. Our results indicate that models must account for stressor interactions to enable responsible management and decision-making.

We Must Stop Fossil Fuel Emissions to Protect Permafrost Ecosystems

“…The combined effects of rising CO 2 , increased meltwater inputs, and changes in circulation could push calcium carbonate below critical saturation thresholds in the Arctic Ocean's surface water by the mid-21st Century (Steinacher et al, 2009;Denman et al, 2011). In combination with increasing thermal stresses, this could trigger major breakdowns in planktonic and benthic food webs (Yamamoto-Kawai et al, 2009;Denman et al, 2011;Arrigo et al, 2020). For example, the combination of increased light availability from sea ice loss and changes in water and nutrient delivery from terrestrial ecosystems is estimated to have increased primary productivity in the Arctic Ocean by roughly 60% over the last 20 years (Lewis et al, 2020;Terhaar et al, 2021).…”

Emergent interactive effects of climate change and contaminants in coastal and ocean ecosystems

“…CC drivers operate alongside with contaminants synergistically and thus contribute to environmental change at a global scale. Moreover, some regions, such as the Arctic, are known to be more vulnerable and are therefore changing more rapidly due to the multiple co-occurring changes in temperature, freshwater content, sea ice cover, nutrient concentrations, and pH (Wassmann et al, 2011;Stjern et al, 2019;Arrigo et al, 2020;AMAP, 2021b). In addition, to these CC drivers, the Arctic ecosystems also present a high vulnerability to radionuclides contamination due to nuclear testing in the 1950s with additional inputs from accidents, weapons tests and substantial amounts of radioactivity dumped at sea with the potential for corrosion/leakage of the containers (UNSCEAR, 2000;AMAP, 2015).…”

“…It will be necessary to increase our knowledge from laboratory, ecosystem-based field and process studies, as well as modelling, to have an overarching international action to facilitate and foster broad bidirectional science-policy interactions. The synergistic effects of various CC drivers are still mostly unexplored and demand urgent research studies (Cabral et al, 2019;Arrigo et al, 2020;Jin et al, 2021;Kibria et al, 2021).…”

Geography needs science, science needs Geography

“…Myers-Smith et al, 2020: 41 authors, 5 from geography departments), ecosystem risks (e.g. Arrigo et al, 2020: 16 authors, 3 from a geography department), flood disasters (e.g. Aerts et al, 2018: 10 authors, 3 from geography departments); carbon storage (e.g.…”