Ads
related to: humic acid concentration in water
Search results
Results From The WOW.Com Content Network
"Humic substances" is an umbrella term covering humic acid, fulvic acid and humin, which differ in solubility. By definition, humic acid (HA) is soluble in water at neutral and alkaline pH, but insoluble at acidic pH < 2. Fulvic acid (FA) is soluble in water at any pH. Humin is not soluble in water at any pH.
The formation of a humic lakes via organic runoff has a dramatic effect on the lake ecosystem. Increases in the lake’s acidity make it difficult for fish and other organisms to proliferate. The quality of the lake for use as drinking water also decreases as the carbon concentration and acidity increase.
Potassium humate is used in agriculture as a fertilizer additive to increase the efficiency of fertilizers especially nitrogen- and phosphorus-based fertilizer inputs. Other salts of humic acid are manufactured, mainly sodium humate, which is used in animal health supplements. It also can be used in aquaculture.
Soil consists of both mineral (inorganic) and organic components. The organic components can be subdivided into fractions that are soluble, largely humic acids, and insoluble, the humins. Humins make up about 50% of the organic matter in soil. [1]
The following chart shows the solubility of various ionic compounds in water at 1 atm pressure and room temperature (approx. 25 °C, 298.15 K). "Soluble" means the ionic compound doesn't precipitate, while "slightly soluble" and "insoluble" mean that a solid will precipitate; "slightly soluble" compounds like calcium sulfate may require heat to precipitate.
However both colour and turbidity reduce the amount of light penetrating the water and can have significant impact on algae and macrophytes. Some algae in particular are highly dependent on water with low colour and turbidity. Many rivers draining high moor-lands overlain by peat have a very deep yellow brown colour caused by dissolved humic acids.
The International Humic Substances Society maintains a collection of standard and reference samples of humic and fulvic acids extracted and fractionated from leonardite, river water, a mineral soil, and peat, plus natural organic matter isolated from river water by reverse osmosis, [4] without fractionation. [5]
It is a rich source of humic acid (up to 90%) [2] and is used as a soil conditioner, as a stabilizer for ion-exchange resins in water treatment, [3] in the remediation of polluted environments and as a drilling additive. [4] It was named after A. G. Leonard, first director of the North Dakota Geological Survey, in recognition of his work on ...