Rivers, particulate organic carbon

The quantity of primary production that is exported from the upper ocean is said to be equivalent to new production (18, 19) New primary production is that associated with allocthonous nutrients (i.e., those upwelled or mixed into the euphotic zone or input via rivers and rain). In order for steady state to be maintained, an equivalent flux out of the euphotic zone is required. Earlier studies (19) suggested that sediment-trap measurements of particulate organic carbon (POC) flux were equivalent to new primary production however, recently it has become clear that these measurements probably represent only a... 

Degens, E.T. and Ittekkot, V., 1985. Particulate organic carbon - and overview. In Degens et al. (eds.), Transport of Carbon and Minerals in Major World Rivers. Pt. 3, Mitt. Geol.-Palaont. Inst. Univ. Hamburg, SCOPE/UNEP Sonderbd. (in press). 

Trefry, J.H., Metz, S., Nelsen, T.A., Trocine, T.P., and Eadie, B.A. (1994) Transport and fate of particulate organic carbon by the Mississippi River and its fate in the Gulf of Mexico. Estuaries 17, 839-849. 

Verity, P.G. (2002b) A decade of change in the Skidaway River estuary. II. Particulate organic carbon, nitrogen, and chlorophyll a. Estuaries 25, 961-975. 

Wang, X.C., Chen, R.F., and Gardner, GB. (2004) Sources and transport of dissolved and particulate organic carbon in the Mississippi River estuary and adjacent coastal waters of the northern Gulf of Mexico. Mar. Chem. 89, 241-256. 

Carbon is transported into the Amazon River/ocean mixing zone in numerous forms including dissolved inorganic carbon (DIC), dissolved organic carbon (DOC), and particulate organic carbon (POC). The average DIC, DOC, and POC concentrations in Amazon River water are 460, 275, and 180 pmol L-1 (Richey et al. 1991), which indicates that DOC supply exceeds POC supply and that DIC is the most abundant form of carbon in the river. Sholkovitz et al. (1978) noted that most riverine dissolved... 

Kao, S. J., and Liu, K. K. (1996). Particulate organic carbon export from a subtropical mountainous river (Lanyang-Hsi) in Taiwan. Limnol. Oceanogr. 41, 1749—1757. 

MiUiman J. D., Quinchun X., and Zuosheng Y. (1984) Transfer of particulate organic carbon and nitrogen from the Changjiang River to the ocean. Am. J. Sci. 284, 824-834. 

Many of the hydrocarbons have small but measurable solubilities in water. Data obtained by Sutton and Calder (1974) indicate that normal paraffins are less soluble in sea water than in distilled water (for example 0.8 compared with 1.1 )ng r for the n-C2o). This plays a significant role in the estuarine environment. If the river water is saturated with respect to normal paraffins, salting out will occur in the fresh water/sea water mixing zone and salted-out molecules may be adsorbed onto mineral or organic particles. So, estuaries may act to limit the amount of dissolved molecules and may increase the amount of particulate organic carbon entering the ocean (Sutton and Calder, 1974). 

Liu WC, Wang R, Ji P (1997) Study on particulate organic carbon in the East China Sea. Oceanol Limnol Sin 28 139-143 (in Chinese with English abstract) Liu XC, Shen HT, Huang QH (2002) Concentration variation and flux estimation of dissolved inorganic nutrient from the Changjiang River into its estuary. Oceanol Limnol Sin 33(3) 332-340 (in Chinese with Enghsh abstract)... 

Figure 3 presents data on the distribution of volume of water above different depth intervals, and the inputs of organic carbon to surface waters above the same depths. High inputs of organic matter to a small volume of water over the shelves are registered. This is due to inputs from rivers, not only of particulate carbon, but also of mineral nutrients which increase the primary productivity and organic input in these regions. 

Kendall, C., S. R. Silva, and V. J. Kelly. 2001. Carbon and nitrogen isotopic compositions of particulate organic matter in four large river systems across the United States. Hydro-... 

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