Marine environments suspended solids

The presence of suspended solid materials increases the extent of LAS biodegradation [13,28], but the rate of the process remains invariable. The influence of the particulate material is due specifically to the increased density of the microbiota associated with sediments. However, suspended solids may also reduce the bioavailability of IAS as a result of its sorption onto preferential sites (e.g. clays, humic acids), although this is a secondary effect due to the reversibility of the sorption process. Salinity does not affect IAS degradation directly, but could also reduce LAS bioavailability by reducing the solubility of this molecule [5], Another relevant factor to be taken into account is that biodegradation processes in the marine environment could be limited by the concentration of nutrients, especially of phosphorus and nitrogen [34],... 

Humic acids (HA) are organic polyelectrolytes, which are most commonly identified with the organic material present in contemporary solid particles. HS are present in practically all soils and suspended and bottom sediments of rivers, lakes, estuaries, and shallow marine environments. 

The AP concentrations in sediments were also greater in creeks than in the brackish and marine environment. The average concentrations of NP, OP, and BP in sediment from Lake Shihwa were 609, 18, and 10 ng g-1 dw, respectively (Khim et al., 1999a). The NP concentration was detected up to 116700 ng g-1 dw in suspended solids, and 32000 n g-1 dw in sediments. The concentrations of APs and BPA in soil samples from the national monitoring sites of NIER were at a few ppb levels, implying that little APs and BPA were introduced into soil. 

Bis(2-chloroethyl)ether s former production and use in the textile industry and as solvent in natural and synthetic resins may result in its release to the environment through various waste streams. If released to air, a vapor pressure of 1.55 mm Hg at 25°C indicates that bis(2-chloroethyl)ether will exist solely as vapor in the ambient atmosphere. Vapor-phase bis(2-chloroethyl)ether will be degraded in the atmosphere by reaction with photochemically produced hydroxyl radicals the half-life for this reaction in air is estimated to be 5 days. If released into soil, bis(2-chloroethyl) ether has a high mobility. Many ethers are known to be resistant to biodegradation. Volatilization from moist soil surfaces is an important fate process. If released into water, bis(2-chloroethyl)ether is not adsorbed by suspended solids and sediment in water. Volatilization from water surfaces is an important fate process. The volatilization half-life from a model river and a model lake is estimated as approximately 40 h and 16 days. Bis(2-chloroethyl) ether is a marine pollutant and its release to the sea is prohibited by the International Convention since 1973. ... 

A mathematical model is formulated to describe the first-order kinetics of ionic copper released into a marine environment where sorption on suspended solids and complexation with dissolved organic matter occur. Reactions are followed in time until equilibrium, between the three copper states is achieved within about 3 hr (based on laboratory determinations of rate and equilibrium constants). The model is demonstrated by simulation of a hypothetical slug discharge of ionic copper, comparable to an actual accidental release off the California coast that caused an abalone kill. A two-dimensional finite element model, containing the copper submodel, was used to simulate the combined effects of advection, diffusion, and kinetic transformation for 6 hr following discharge of 45 kg of ionic copper. Results are shown graphically. 

There is, within reason, no maximum to the amount of suspended solids that can be determined by this procedure as the sample volume may be reduced when the particulate content of samples increase. In practice the largest amounts likely to be encountered in most truly marine environments away from excessive mud and sand will be about 10,000 mg/m . 

In addition to gases produced naturally in the environment, estuaries tend to be enriched in byproducts of industry and other human activity. A few studies have investigated volatile organic pollutants such as chlorinated hydrocarbons (chloroform, tet-rachloromethane, 1,1-dichloroethane, 1,2-dichlor-oethane, 1,1,1-trichloroethane, trichloroethylene and tetrachloroethylene) and monocyclic aromatic hydrocarbons (benzene, toluene, ethylbenzene, o-xylene and m- and p-xylene). Concentrations of VOCs are controlled primarily by the location of the sources, dilution of river water with clean marine water within the estuary, gas exchange, and in some cases, adsorption onto suspended or settling solids. In some cases (for example, chloroform) there also may be natural biotic sources of the gas. Volatilization to the atmosphere can be an important cleansing mechanism for the estuary system. Since the only estuaries studied to date are heavily impacted by human activity (the Elbe and... 

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