Amount Of Particulate Organic Matter Research Articles

Transport of particulate organic material between salt marsh and estuary

The macrophyte production and the transport of particulate organic matter between march and adjacent estuary have been investigated for a 30 ha salt marsh along the Oosterschelde estuary, The Netherlands. The primary production of macrophytes, measured with Smalley's method, was 837–1030 g dry organic matter.m−2.year−1. Measurements of amounts of particulate organic matter transported through one of the main tidal creeks in the salt march resulted in a net import. On average 31% of the material brought in by the flood settled in the marsh. The majority of this material is smaller than 63 μm. On the other hand large floating material is exported during storm tides, although the quantity seems to be smaller than that of the suspended material imported. The differences between various marshes with regard to export and import of organic matter are explained in terms of marsh level, primary production, turbulent diffusion, sinking and resuspension of particulate matter and biotic transformations.

On the Behavior of Mercury in Some Polluted Seawater

Abstract Most of the mercury in coastal seawater polluted with waste water including mainly organic suspended matter is associated with suspended matter, especially particulate organic matter. The amount of mercury adsorbed on a given amount of particulate organic matter nearly obeys Freundlich’s adsorption isotherm at mercury concentrations less than 15 ppm in particulate organic matter. The mercury in suspended matter is not much reduced by the addition of tin(II) chloride. Thus, to get the total value of the mercury concentration, the water samples must be heated with the addition of a sulfuric and nitric acid mixture to decompose the suspended matter.

FEEDING RATE OF CALANUS FINMARCHICUS IN RELATION TO ENVIRONMENTAL CONDITIONS

(1) The filtering rate of Calanus finmarchicus on the diatom, Nitzschia closterium, was measured under different conditions of diatom concentration, light and temperature, by observing the reduction in concentration of the diatoms. Change in diatom concentration had no effect on the rate of filtration. There was some evidence of a diurnal feeding rhythm with greater activity at night. Feeding was most rapid at 8° C., slower at 13° and 3°.(2) Studies on the growth of Calanus supplied with different concentrations of diatoms indicated that the food requirement is less than has been calculated from oxygen consumption measurements. This is also borne out by comparing the amount of particulate organic matter in the sea with the rate of feeding measured in the laboratory.(3) The view that the feeding activity of Calanus is automatic filtering is favored by these experiments.(4) Approximately one-half the organic nitrogen content of Nitzschia is in a form available to Calanus.(5) These results are correlated with the ecology of Calanus as studied in the field.