Acidification drainage water

The acidifying effect of the vegetation is therefore limited to a regulation of the wash-out of the basic components formed by vitrification of the minerals. In addition to this, humus components (fulvic acid), and mineralization of reduced sulphur and nitrogen compounds may to some extent contribute to the acidity and the anion concentration in the drainage water. But this seems to be of limited significance for the "regional acidification problem". 

The acidification of the drainage water is particularly related to sulphate ions. Along their route in the soil, the sulphate ions must bring with them an equivalent amount of hydrogen ions or other... 

Fluoride Drainage water from water treatment plant Distillation UV—Vis 0.05—15 mg L 1 Flow injection system sulphuric and phosphoric acids for sample acidification determination relies on the La(III)—fluoride—alizarin complex. [311]... 

Figure 5.3. Forest N cycling and acidification. Atmospheric N inputs and N outputs to drainage waters are shown in italics. Soil processes (left) and plant processes (right) are clustered within ovals. Dashed lines indicate soil-plant exchanges (plant N uptake or organic N return to soil). Solid lines show processes within soils or plants. Dotted lines show fluxes into or out of forests. Values in brackets refer to net consumption [-] or production [+] of 1 mol associated with the transformation of 1 mol N. When forest N cycles are closed (small N inputs and outputs), the sum of consumed and produced by soil and plant processes is zero and no acidity is generated. When 1 mol of organic N is mineralized (1 mol consumed) and subsequently nitrified (2 mol produced), 1 mol remains to acidify soil or drainage water if nitrate is not removed from soil and converted to organic form by plants. Denitrification to any of three gaseous products consumes 1 mol H. Direct inputs of acidity can also result from ammonium and nitrate deposition. Reprinted from Nadelhoffer (2001) with permission from Elsevier...

The hydrology and chemistry of lakes and streams are highly individualistic. Lakes surrounded by poorly buffered soil and underlain by granitic bedrock appear to be more susceptible to acidification when exposed to acid rain (Havas et al. 1984). Other lake characteristics such as dominance of atmospheric input or surface/subsurface runoff as the major source of water, type and depth of soil, bedrock characteristics, lake size and depth, area of the drainage basin, and residence time of water in the lake are all features that influence the response of a lake to acid rain. 

The acidification of dumps and waters is a common problem in many mining areas. The according acidic mine drainage (AMD) has been investigated (e.g. Alpers and Blowes 1994 Fischer et al. 1987 U.S. Dept, of the Interior 1994). Oxidation of marcasite in dumps results in a first step in acid-reaction products which are then washed out. The most significant reactions of pyrite and marcasite oxidation are listed in Table 8.2 (after Stumm and Morgan 1981 MattheB 1990). 

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