摘要：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.
