Fjords as Aquatic Critical Zones (ACZs)

Thomas S. Bianchi, Sandra Arndt, William E.n. Austin, Douglas I. Benn, Sebastien Bertrand, Xingqian Cui, Johan C. Faust, Katarzyna Koziorowska-makuch, Christopher M. Moy, Candida Savage, Craig Smeaton, Richard W. Smith, Jaia Syvitski

Research output: Contribution to journalArticlepeer-review

102 Citations (Scopus)


In recent decades, the land-ocean aquatic continuum, commonly defined as the interface, or transition zone, between terrestrial ecosystems and the open ocean, has undergone dramatic changes. On-going work has stressed the importance of treating Aquatic Critical Zones (ACZs) as a sensitive system needing intensive investigation. Here, we discuss fjords as an ACZ in the context of sedimentological, geochemical, and climatic impacts. These diverse physical features of fjords are key in controlling the sources, transport, and burial of organic matter in the modern era and over the Holocene. High sediment accumulation rates in fjord sediments allow for high-resolution records of past climate and environmental change where multiple proxies can be applied to fjord sediments that focus on either marine or terrestrial-derived components.

Humans through land-use change and climatic stressors are having an impact on the larger carbon stores in fjords. Sediment delivery whether from accelerating erosion (e.g. mining, deforestation, road building, agriculture) or from sequestration of fluvial sediment behind dams has been seriously altered in the Anthropocene. Climate change affecting rainfall and river discharge into fjords will impact the thickness and extent of the low-salinity layer in the upper reaches of the fjord, slowing the rate of the overturning circulation and deep-water renewal – thereby impacting bottom water oxygen concentrations.
Original languageEnglish
Article number103145
Number of pages25
JournalEarth-Science Reviews
Early online date2 Mar 2020
Publication statusPublished - 1 Apr 2020


Dive into the research topics of 'Fjords as Aquatic Critical Zones (ACZs)'. Together they form a unique fingerprint.

Cite this