“Whoa! It's like Spotify but for academic articles.”

Instant Access to Thousands of Journals for just $40/month

Caribbean octocorals record changing carbon and nitrogen sources from 1862 to 2005

Caribbean octocorals record changing carbon and nitrogen sources from 1862 to 2005 During the last century, the global biogeochemical cycles of carbon (C) and nitrogen (N) have been drastically altered by human activities. A century of land‐clearing and biomass burning, followed by fossil fuel combustion have increased the concentration of atmospheric CO2 by approximately 20%, and since the mid‐1900s, the use of agricultural fertilizers has been the primary driver of an approximate 90% increase in bioavailable N. Geochemical records obtained through stable isotope analysis of terrestrial and marine biota effectively illustrate rising anthropogenic C inputs. However, there are fewer records of anthropogenic N, despite the enormous magnitude of change and the known negative effects of N on ecosystem health. We used stable isotope values from independent octocorals (gorgonians) sampled across the Western Atlantic over the last 143 years to document human perturbations of the marine C and N pools. Here, we demonstrate that in sea plumes δ13C values and in both sea plumes and sea fans δ15N values declined significantly from 1862 to 2005. Sea plume δ13C values were negatively correlated with increasing atmospheric CO2 concentrations and corroborate known rates of change resulting from global fossil fuel combustion, known as the Suess effect. We suggest that widespread input of agricultural fertilizers to near‐shore coastal waters is the dominant driver for the decreasing δ15N trend, though multiple anthropogenic sources are likely affecting this trend. Given the interest in using δ15N as an indicator for N pollution in aquatic systems, we highlight the risk of underestimating contributions of pollutants as a result of source mixing as demonstrated by a simple isotope‐mixing model. We conclude that signals of major human‐induced perturbations of the C and N pools are detectable in specimens collected over wide geographic scales, and that archived materials are invaluable for establishing baselines against which we can assess environmental change. http://www.deepdyve.com/assets/images/DeepDyve-Logo-lg.png Global Change Biology Wiley
Loading next page...
 
/lp/wiley/caribbean-octocorals-record-changing-carbon-and-nitrogen-sources-from-HycexDy00G

You're reading a free preview. Subscribe to read the entire article.

And millions more from thousands of peer-reviewed journals, for just $40/month

To be the best researcher, you need access to the best research

  • With DeepDyve, you can stop worrying about how much articles cost, or if it's too much hassle to order — it's all at your fingertips. Your research is important and deserves the top content.
  • Read from thousands of the leading scholarly journals from Springer, Elsevier, Nature, IEEE, Wiley-Blackwell and more.
  • All the latest content is available, no embargo periods.

Stop missing out on the latest updates in your field

  • We’ll send you automatic email updates on the keywords and journals you tell us are most important to you.
  • There is a lot of content out there, so we help you sift through it and stay organized.