Figure 1.
Photographs showing disturbance to salt marsh (Spartina alterniflora) caused by accumulation of seagrass wrack.
A) fresh wrack (Thallasia testudinum) accumulation after a storm; and B) a ‘halo’ of bare sediment after prolonged wrack smothering.
Figure 2.
Organic carbon content (mean ± standard error) of sediment at different depths below the surface.
Samples taken from disturbed and undisturbed salt marsh (Spartina alterniflora).
Figure 3.
The amount of salt marsh plant material (mean + standard error) in sediments from disturbed and undisturbed plots.
Sediment cores were sectioned into 2 depths and all plant material was quantified to determine its contribution to the organic carbon content of the sediments. a) Absolute biomass of salt marsh (Spartina alterniflora) in sediment cores from disturbed and undisturbed plots at two depth intervals. Plant biomass was higher in the 1-5cm depths than in the surface sediments. b) Percentage of organic carbon (C) in each sediment core resulting from salt marsh plant biomass in disturbed and undisturbed salt marsh sediments.
Figure 4.
Conceptual diagram illustrating the possible fates of carbon (C) lost from disturbed salt marsh: (a) remineralization of C by microbes and release as CO2; (b) consumption of C by detritivores and grazing animals; (c) physical export (into deeper water, other parts of the marsh, or other habitats), which could lead to re-burial of the C.
Diagram produced using the Integration and Application Network (IAN), University of Maryland Center for Environmental Science, Cambridge, Maryland.