Humus

The pH is determined in both water and 0.1 M KCI (10 g soil -i- 25 ml solution) as detailed in VDLUFA (1991, section A.5.1.1). Note VDLUFA = Verband Deutscher Landwirtschaftlicher Untersuchungs- und Forschungsanstalten, whose website home page is  

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Color. Many water samples have a yellow to brownish-yeUow color which is caused by natural substances, eg, leaves, bark, humus, and peat material. Turbidity in a sample can make the measurement of color uncertain and is usually removed by centrifiigation prior to analysis. The color is usually measured by comparison of the sample with known concentrations of colored solutions. A platinum—cobalt solution is used as the standard, and the unit of color is that produced by 1 mg/L platinum as chloroplatinate ion. The standard is prepared from potassium chloroplatinate (K PtCl ) and cobalt chloride (C0CI26H2O). The sample may also be compared to suitably caUbrated special glass color disks. 

The importance of the final settling, or humus, tank can be seen by an examination of what occurs in the trickling filter itself. A new filter is broken in by applying settled sewage as in the normal operation. After a period of time the microbial, or zoogleal, mass forms on the filter medium and stabilizes the waste. Waste material is first adsorbed, and then assimilated by the microorganisms. 

The following day the acid liquid is filtered with suction through a large Buchner funnel, to remove large quantities of humus which are produced. The humus on the filter is washed with two 350-cc. portions of water and finally with two 300-cc. portions of benzene. The filtered liquid and aqueous washings have a volume of approximately 10 1. The s-methylfurfural is... 

The extractions should be carried out immediately after filtration since further quantities of humus are deposited if the liquid is allowed to stand. 

A humus-like, biologically stable end product is produced. 

Detention Time Waste activated sludge only, after sludge thickening. 10 -15 days volumetric displacement time. If sludge temperatures are much less than 60°F, more capacity should be provided. Primary sludge mixed with waste activated or trickling filter humus. 20 days displacement time in moderate climates. 

Composting is the process of aerobic thermophilic decomposition of organic wastes to a relatively stable humus. Decomposition results from the biological activity of microorganisms which exist in the waste. 

In contrast, composting processes utilize a mixture of solids and yard waste under controlled environmental conditions to produce a disinfected, humus-like product. Three common composting systems are a horizontal agitated reactor, a horizontal nonagitated reactor, and an aerated static pile system (nonproprietary). Compost can be marketed as a soil conditioner in competition with such products as peat, soil, and mulch. Although a large potential market exists, significant effort is required to penetrate this market. Yard waste revenue of 6.50/m (S5/yd ) and product revenue of 2.00/m ( 1.50/yd ) appear to be reasonable market values based on various studies reported on the Web. 

Humus The dark organic material in soils, produced by the decomposition of soils. The matter that remains after the bulk of detritus has beenconsumed (leaves, roots). Humus mixes with top layers of soil (rock particles), supplies some of the nutrients needed by plants -increases acidity of soil inorganic nutrients more soluble under acidic conditions, become more available, EX. wheat grows best at pH 5.5-7.0. Humus modifies soil texture, creates loose, crumbly texture, that allows water to soak in and nutrients retained permits air to be incorporated into soil. 

Runoff Water running down slopes rather than sinking in (again, result of poor humus content) Ex. erosion due to deforestation... 

Damm, m. dam, dike, bank (Med.) perineum Dammar-finiis, m. dammar varnish, -harz, n dammar resin, dammar, dammen, v.t. dam, dam up, stop up curb. Dammerde, /. mold, humus (Founding) pit sand. 

Dungerde,/. mold, humus, compost. DUngerfabrik, /. fertilizer factory, diingerfordemd, a. requiring fertilizer. DUnger-salz, n. Dungesalz. -versuch, m. 

Humulo-cbinon, n. humuloquinone. -hydro-cbinon, n. humulohydroquinone. Humus-bildung, /. humus formation, -decke, /. covering of humus, -erde, /. humus hu-moiis soil,... 

Humus-saure, /. humic acid, -schicht, /. layer of humus, -stoff, m. humus substance. Hund. m. dog hoimd (Mach.) rammer, monkey (Mining) car. 

Mulm, m. ore dust, earthy ore mold, humus decay. 

Wald-, wood, forest, wild, -ahom, m. sycamore, -bau, n. silviculture, forestry, -baum, m. forest tree, -boden, m. forest soil. Walden sche Umkehmng. Walden inversion. Wald-gewachs, n. forest plant, -humus m. 

Thus, based on material applications, the following polymers are important natural rubber, coal, asphaltenes (bitumens), cellulose, chitin, starch, lignin, humus, shellac, amber, and certain proteins. Figure 4 shows the primary structures of some of the above polymers. For detailed information on their occurrence, conventional utilization, etc., refer to the references cited previously. 

F. J. Stevenson, Humus Chemistry, Genesis, Composition, Reactions, Wiley-Interscience, New York (1982). M. Schnitzer and S. U. Khan, Humic Substances in the Environment., Marcel Dekker, Inc., New York (1972). 

To protect buried metals from premature breakdown it must suffice to say that protective coatings and other methods must be applied against factors such as the effects of galvanic currents, composition of the moisture in the ground, humus acids, bacteria, etc. (See Section 14.8.)... 

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