Erratum to: Microbial decomposition process of organic matter in sinking particles, resuspendable particles, and bottom sediments at a coastal fish farming area

The study of heavy metal speciation in bottom sediments of the Vyshnevolotsky water reservoir is presented in this paper. Sequential selective procedure was used to determine the heavy metal speciation in bottom sediments and thermodynamic calculation — to determine ones in interstitial water. It has been shown that Mn are mainly presented in exchangeable and carbonate forms; for Fe, Zn, Pb и Co the forms are related to iron and manganese hydroxides is played an important role; and Cu and Ni are mainly associated with organic matter. In interstitial waters the main forms of heavy metal speciation are free ions for Zn, Ni, Co and Cd, carbonate complexes for Pb, fulvate complexes for Cu. Effects of particle size and organic matter content in sediments on distribution of mobile and potentially mobile forms of toxic elements have been revealed.

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Organic Matter Decomposition in Bottom Sediments of the Reservoirs of the Volga and Kama Rivers. Role of Methanogenesis

Hydrobiological Journal ◽

10.1615/hydrobj.v52.i1.80 ◽

2016 ◽

Vol 52 (1) ◽

pp. 81-88

Author(s):

A. N. Dzyuban

Keyword(s):

Organic Matter ◽

Bottom Sediments ◽

Organic Matter Decomposition

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Characteristics of fouling due to clay-organic substances in potable water treatment by ultrafiltration

Water Science & Technology ◽

10.2166/wst.1996.0201 ◽

1996 ◽

Vol 34 (9) ◽

pp. 157-164 ◽

Cited By ~ 2

Author(s):

Kim C.-H. ◽

M. Hosomi ◽

A. Murakami ◽

M. Okada

Keyword(s):

Molecular Weight ◽

Organic Matter ◽

Humic Acid ◽

Fulvic Acid ◽

Size Distribution ◽

Ultrafiltration Membrane ◽

Organic Substances ◽

Decomposition Products ◽

Microbial Decomposition ◽

Fouling Materials

Effects of clay on fouling due to organic substances and clay were evaluated by model fouling materials and kaolin. Model fouling materials selected were protein, polysaccharide, fulvic acid, humic acid and algogenic matter (EOM:ectracellular organic matter, microbial decomposition products) and kaolin was selected as the clay material. Polysulfone membrane (MWCO(Molecular Weight Cut-Off) 10,000, 50,000 and 200,000) was used as an ultrafiltration membrane. In particular, the flux measurement of solutions containing algogenic matter used an ultrafiltration membrane of MWCO 50,000. The flux of protein and polysaccharide with coexistence of kaolin increased in the case of the ratio of MW/MWCO being greater than one, but did not increase in the case of the MW/MWCO ratio being below one. In contrast, the flux of fulvic acid and humic acid with coextence of kaolin decreased regardless of the ratio of MW/MWCO. The addition of dispersion agent and coagulant in the organic substances and kaolin mixture solution changed the size distribution of kaolin, and resulted in a change of the flux. EOM and microbial decomposition products decreased with the increase of the fraction of organic matter having molecular weight more than MWCO of membrane. The flux of the algogenic organic matter with coexistence of kaolin decreased with the increase of the amount of kaolin. It was suggested that the decline of the flux with coexistence of kaolin was due to the change of the resistance of the kaolin cake layer corresponding to the change in kaolin size distribution with charge.

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Fish farming in Denmark: environmental impact of regulative legislation

Water Science & Technology ◽

10.2166/wst.1995.0365 ◽

1995 ◽

Vol 31 (10) ◽

pp. 73-84 ◽

Cited By ~ 3

Author(s):

T. M. Iversen

Keyword(s):

Organic Matter ◽

Environmental Impact ◽

Freshwater Fish ◽

Aquatic Environment ◽

Action Plan ◽

Fish Farming ◽

Fish Farms ◽

Nitrogen And Phosphorus ◽

Local Impact ◽

The Impact

The main environmental problems associated with fish farming in Denmark are attributable to the dam, the “dead reach” and nutrient and organic matter discharge. The environmental regulation of fish farming in Denmark started with the Environmental Protection Act of 1974, the Statutory Order of 1985 forbidding wet feed, and the Action Plan on the Aquatic Environment of 1987. In the case of freshwater fish farms, the latter was implemented through the measures stipulated in the 1989 Statutory Order on Fish Farms. The impact of Danish legislative measures to reduce and regulate the environmental effects of freshwater fish farms can be summarized as follows: - the number of fish farms has been reduced from about 800 in 1974 to about 500 at present; - production has tripled since 1974 and has been stable since 1989; - a change from wet to dry feed has reduced the environmental impact of the farms; - the national goals of the Action Plan on the Aquatic Environment of 1987 for reducing fish farm discharges of organic matter, nitrogen and phosphorus have been fulfilled. The main remaining problems are that: - the local impact of fish farms on downstream stream quality is still much too high in about 15% of cases; - the problem of the passage of migrating invertebrates and fish is still unsolved at some farms; - the problems posed by “dead reaches” are still unsolved. It is concluded that sustainable fish farming is possible in Denmark, but with the present technology production will have to be significantly reduced.

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