Environment freshwater

S.A. Visser (1984). Seasonal changes in the concentration and color of humic substances in some aquatic environments. Freshwater Biol., 14,79-87. 

In Europe, there is currently no standard test method [41 -43 ]. The technical committee 261, which has been operating since 1991, is setting up the standardization of bio degradability testing methods in the field of packaging and the environment. The European Committee of Normalization (ECN) has written a draft about the evaluation of the ultimate bio degradability under controlled composting conditions (Table 2). Other tests are in preparation in different environmental conditions aerobic and anaerobic environment, freshwater, etc. 

Calcium chloride is found in the marine environment. The elemental composition of seawater is 400 ppm calcium, 18,900 ppm chlorine, and many organisms and aquatic species are tolerant of these concentrations. Toxicity arises either from the invasion of freshwater in otherwise saltwater environments or possible toxic doses of calcium chloride from spills, surface mnoff, or underground percolation into typically freshwater streams or aquifers. Various agencies have guidelines for calcium and chloride in potable water (41). The European Economic Community (EEC) is the only agency to have a minimum specification for calcium in softened water. 

Consultants are equipped to monitor the quality of freshwater, estuarine and marine environments and can make field measurements of a variety of water-quality parameters in response to pollution incidents. For example, reasons for the mortality of marine shellfish and farmed freshwater fish have been determined using portable water-analysis equipment. Various items of field equipment are, of course, also employed in baseline studies and monitoring, respectively, before and after the introduction of new effluent-disposal schemes. 

The major source of plutonium in natural waters is the atmospheric fallout from nuclear weapons tests. Fallout plutonium is ubiquitous in marine and freshwater environments of the world with higher concentrations in the northern hemisphere where the bulk of nuclear weapons testing occurred(3). Much of the research on the aquatic chemistry of plutonium takes place in marine and freshwater systems where only fallout is present. 

Meylan S, Behra R, Sigg L (2003) Accumulation of Cu and Zn in periphyton in response to dynamic variations of metal speciation in freshwater. Environ Sci Technol 37 5204... 

Morin S, Duong TT, Herlory O, Feurtet-Mazel A, Coste M (2008) Cadmium toxicity and bioaccumulation in freshwater biofilms. Arch Environ Contam Toxicol 54 173... 

The area of California influenced by a Mediterranean climate is home to over 30 million people. Climate variability and human water demand make freshwater a very precious resource. Allocations of water to cities, agriculture, and the environment create continual tension as demands for this vital and over-allocated resource grow. This paper presents a brief overview of water resource science and policy in a Mediterranean climate with substantial challenges from climate variability, climate change, and increasing human need. 

Butyltin compounds, in contrast, are produced only anthropogenically. Besides the applications covered in this CICAD, there exist other applications of butyltin compounds that may represent a significant source of these substances in the environment. In particular, the use of tributyltin compounds in antifouling coatings represents a significant source of these substances in the marine and freshwater environments. Hence, many of the measured concentrations reported will relate predominantly to this use. 

Much of this is in the public domain, but various additional unpublished information has been supplied by industry. For the purposes of the environmental effects assessment, the focus is on the freshwater environment. 

Choudhury C, Ray AK, Bhattacharya S, et al. 1993. Non lethal concentrations of pesticide impair ovarian function in the freshwater perch, Anabas testudineus. Environ Biol Fishes 36 319-324. 

Muir J, Eduljee G. 1999. PCP in the freshwater and marine enviromnent of the European Union. Sci Total Environ 236 41-56. 

Collings V.G. (1964) The freshwater environment and its significance in industry. JAppl Bacterial, 27, 143-150. 

Fleming EJ, EE Mack, PG Green, DC Nelson (2006) Mercury methylation from unexpected sources molybdate-inhibited freshwater sediments and an iron-reducing bacterium. Appl Environ Microbiol 72 457-464. 

Ranjard L, S Nazaret, B Coumoyer (2003) Freshwater bacteria can methylate selenium through the thiopurine methyltransferase pathway. Appl Environ Microbiol 69 3784-3790. 

Subba-Rao RV, HE Rubin, M Alexander (1982) Kinetics and extent of mineralization of organic chemicals at trace levels in freshwater and sewage. Appl Environ Microbiol 43 1139-1150. 

Wu Q, DL Bedard, J Wiegel (1997a) Effect of incubation temperature on the route of microbial reductive dechlorination of 2,3,4,6-tetrachlorobiphenyl in polychlorinated biphenyl (PCB)-contaminated and PCB-free freshwater sediments. Appl Environ Microbiol 63 2836-2843. 

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