Access

You are not currently logged in.

Access JSTOR through your library or other institution:

login

Log in through your institution.

Journal Article

Compositions and Fluxes of Particulate Organic Material in the Amazon River

John I. Hedges, Wayne A. Clark, Paul D. Quay, Jeffrey E. Richey, Allan H. Devol and Umberto de M. Santos
Limnology and Oceanography
Vol. 31, No. 4 (Jul., 1986), pp. 717-738
Stable URL: http://www.jstor.org/stable/2836965
Page Count: 22
Were these topics helpful?
See something inaccurate? Let us know!

Select the topics that are inaccurate.

Cancel
  • More info
  • Add to My Lists
  • Cite this Item
Compositions and Fluxes of Particulate Organic Material in the Amazon River
Preview not available

Abstract

Lignin, elemental, and stable carbon isotope compositions are reported for local plants and for coarse $(> 63 \mu m)$ and fine $(< 63 \mu m)$ suspended particulate materials collected along a 1,950-km reach of the lower Amazon River during four contrasting stages of the 1982-1983 hydrograph. Fluxes of chemically recognizable lignin in the two size classes generally parallel each other along the mainstem with the fine fraction usually predominating. Particulate organic matter transported in the coarse size fraction of the mainstem and its major tributaries is composed of recently formed and well preserved tree leaf debris along with some wood. Organic matter in the fine size fraction is comparatively old, degraded, and rich in immobilized nitrogen and derives primarily from soils. C-4 grasses, which are abundant in the mainstem floodplain (varzea), are not major components of either the coarse or fine particulate material in the river. Particulate organic matter in both size fractions is introduced largely from upstream sources within the Rio Solimões and Rio Madeira drainage basins. Most of this organic matter is unreactive and is transported conservatively with mineral particles along the Amazon mainstem. However, some downstream compositional trends are seen in both size fractions which reflect the addition or exchange of highly degraded, 13C-depleted, and lignin-poor organic materials from lower basin sources.

Page Thumbnails

  • Thumbnail: Page 
717
    717
  • Thumbnail: Page 
718
    718
  • Thumbnail: Page 
719
    719
  • Thumbnail: Page 
720
    720
  • Thumbnail: Page 
721
    721
  • Thumbnail: Page 
722
    722
  • Thumbnail: Page 
723
    723
  • Thumbnail: Page 
724
    724
  • Thumbnail: Page 
725
    725
  • Thumbnail: Page 
726
    726
  • Thumbnail: Page 
727
    727
  • Thumbnail: Page 
728
    728
  • Thumbnail: Page 
729
    729
  • Thumbnail: Page 
730
    730
  • Thumbnail: Page 
731
    731
  • Thumbnail: Page 
732
    732
  • Thumbnail: Page 
733
    733
  • Thumbnail: Page 
734
    734
  • Thumbnail: Page 
735
    735
  • Thumbnail: Page 
736
    736
  • Thumbnail: Page 
737
    737
  • Thumbnail: Page 
738
    738
Part of Sustainability