Opportunities and limitations to detect climate-related regime shifts in inland Arctic ecosystems through eco-hydrological monitoring

Abstract

This study has identified and mapped the occurrences of three different types of climate-driven and hydrologically mediated regime shifts in inland Arctic ecosystems: (i)from tundra to shrubland or forest, (ii)from terrestrial ecosystems to thermokarst lakes and wetlands, and (iii)from thermokarst lakes and wetlands to terrestrial ecosystems. The area coverage of these shifts is compared to that of hydrological and hydrochemical monitoring relevant to their possible detection. Hotspot areas are identified within the Yukon, Mackenzie, Barents/Norwegian Sea and Ob river basins, where systematic water monitoring overlaps with ecological monitoring and observed ecosystem regime shift occurrences, providing opportunities for linked eco-hydrological investigations that can improve our regime shift understanding, and detection and prediction capabilities. Overall, most of the total areal extent of shifts from tundra to shrubland and from terrestrial to aquatic regimes is in hydrologically and hydrochemically unmonitored areas. For shifts from aquatic to terrestrial regimes, related water and waterborne nitrogen and phosphorus fluxes are relatively well monitored, while waterborne carbon fluxes are unmonitored. There is a further large spatial mismatch between the coverage of hydrological and that of ecological monitoring, implying a need for more coordinated monitoring efforts to detect the waterborne mediation and propagation of changes and impacts associated with Arctic ecological regime shifts. © 2011 IOP Publishing Ltd.