Organic matter classification

Biomass and substrate must be separately described to establish a concept for classification of wastewater directed toward a description of the microbial processes. For several reasons, e.g., to allow widespread application and to observe a basic mass balance, the organic matter expressed in terms of COD is a central parameter for wastewater quality. According to the concepts used in the active sludge models, the classification of wastewater in a sewer network can also be subdivided as outlined in Figure 3.1 (Henze et al., 1987, 1995a, 2000). A direct interaction between sewer and treatment plant processes is therefore within reach. 

Wilcken, H., Sorge, C., and Schulten, H.-R. (1997). Molecular composition and chemometric differentiation and classification of soil organic matter in Podzol B-horizons. Geoderma 76,193-219. 

Biochemical classification may also be applied and indeed would be most appropriate. However, the three main biochemical classes (polysaccharides, proteins, lipids) represent only approximately 20-30% of the NOM in freshwater bodies, the remainder being an ill-characterised mixture of varying proportions of refractory pedogenic and aquagenic organic matter (PROM and AROM, respectively). The major differences between PROM and AROM are (Buffle, 1988, Chapter 4), for the former ... 

DOT CLASSIFICATION 5.1 Label Oxidizer SAFETY PROFILE Moderately toxic by ingesdon and intraperitoneal routes. A powerful oxidant. Incompadble with Al, As, C, Cu, charcoal, Mn02, metal sulfides, S, dibasic organic acids, organic matter, P. When heated to decomposidon it emits toxic fumes of CT. See also CHLORATES for fire, disaster, and explosion hazards. 

DOT CLASSIFICATION 8 Label Corrosive SAFETY PROFILE A poison by ingestion. Moderately toxic by skin contact. A corrosive irritant to skin, eyes, and mucous membranes. Moderately explosive when exposed to heat. Reacts with water or steam to produce toxic and corrosive fumes. Dangerous reactions with metals e.g., sodium (mixture explodes on impact), potassium (explodes on contact), aluminum (ignition after a delay period). Reacts violently with A1 foil. CdS. PbS. organic matter. P. PCI3. rubber. Ag2S. ZnS. When heated to decomposition it emits highly toxic fumes of CL and I and may explode. See also IODINE and CHLORIDES. 

Reminerahzation of PON and DON to DIN is clearly a key process in models, and also provides some useful illustrations of the classification and evolution of models. The earliest NPZ models represented loss terms from phytoplankton and zooplankton as fluxes directly to the DIN pool. An NPZD model differs from an NPZ model in having an explicit compartment for detritus, or nonfiving organic matter (Edwards, 2001 Franks, 2002). Remineralization from this pool is most simply expressed as... 

McGill W. B. (1996) Review and classification of ten soil organic matter (SOM) models. In Evaluation of Soil Organic Matter Models (eds. D. S. Powlson, P. Smith, and J. U. Smith). Springer, pp. 111-132. 

Soil samples were taken from the experimental field in which spinach is cultivated at the National Institute for Agro-environmental Sciences, Tsukuba, Japan. The top 10 cm of soil was collected from 15 points and then mixed, air-dried, and passed through a 2-mm sieve. For comparison, surface soil was also taken from the adjacent non-cultivated land. The soil classification based on the world reference base for soil resources is Andosols. Relevant soil properties are shown in Table 1. A distinctive feature of this soil is a high amount of organic matter and a higher capacity for phosphate adsorption due to the presence of non-crystalline minerals. 

Large samples of each type could be collected and analyzed in several different laboratories, utilizing the latest techniques for the various humic substances. The classification and analytical methods would be standardized. In this way the extensive reserves of organic matter contained in the world s peatlands could be adequately characterized as to chemical substances. 

Spodosol. A soil characterized by a whitish-grey, highly leached A horizon, and a B spodic horizon that is significantly enriched in organic matter. These soils develop in cool-temperate to temperate, humid climates under coniferous or mixed coniferous and deciduous forests. In the current soil taxonomic system, most Podzol soils (an older classification) are Spodosols. 

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