Aquatic Sciences Meeting, Albuquerque 2001

SS08 Processes at the Benthic Interface (Environmental Connections)

Date: Wednesday, February 14, 2001, Time: 12:00:00 PM

Location: Ruidoso/Pecos

Lee, R, W, Washington State University/School of Biological Sciences, Pullman, USA, rlee@mail.wsu.edu

Oxygen and sulfide transport in the cordgrass Spartina anglica

Spartina anglica is an introduced cordgrass that has extensively colonized estuaries in Washington State. Dense monotypic stands form on previously bare mudflat, dramatically altering habitat and species composition. The success of S. anglica as an invader is likely due in part to physiological tolerance of reducing sediment conditions (low oxygen, elevated hydrogen sulfide). Oxygen transport from the atmosphere via an aerenchyma system may provide oxygen to support root aerobic metabolism and sulfide oxidation. An automated flow-through respirometry system was used to measure S. anglica root oxygen, sulfide, carbon dioxide, and ammonia fluxes. Net oxygen release to the medium was measured in S. anglica grown under flooded, but not drained, conditions. Oxygen release was blocked when above-ground portions of the plant were kept in a N2 atmosphere, indicating that oxygen transport is facilitated by aerenchyma. Sulfide removal from the medium by roots occurred at high rates. A substantial proportion appeared to be lost by volatilization to the atmosphere rather than oxidation at the root surface.

This Session Listing

Aquatic Sciences Meeting, Albuquerque 2001

Quicklinks