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Adsorption of Be, F, B, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, As, Se, Sr, Mo, Tc, Ag, Cd, Sn, Sb, Cs, Ba, Hg, Pb, Bi, and P was measured in a sandy soil and a sandy loam soil at concentration levels closely corresponding to those to be expected for field conditions. Mobilities of the elements in the soils were calculated from the adsorption data. Of the trace elements studied, F, B, and Tc were found to be very mobile in both the sandy and sandy loam soils. Manganese, Sr, and Sb were highly mobile only in the sandy soil, and Mo in the sandy loam soil. In general, sludge solutions appeared to increase the mobility of elements in a soil. This is due to a combination of complexation by dissolved organic compounds, high background concentrations, and high ionic strengths of the soil solutions. The relative effects of these factors vary strongly among elements.Equations were derived predicting the rates of accumulation in soils and accompanying increases in the soil solutions of trace elements added with sewage sludge.When adsorption was related to soil organic matter content, for many trace elements the strength of adsorption was found to depend only on pH, increasing with increasing pH.

Results obtained previously on distribution and behaviour of phosphate between organic and inorganic forms in pig slurries are extended to slurries from wastes of hens, cows and calves. Organic P in the slurries varied from about 1 to 15% of total P, with slurries from veal calves having the lowest content of organic P. In all slurries roughly half of organic P in solution had a high molecular weight (50000 and higher) and is therefore potentially mobile in soils.

Cattle slurry was surface-applied to bare soil in two experiments in September-November 1987, while in April-May 1988 two experiments were carried out in which the slurry was mixed with the upper 6 cm of the soil with a cultivator immediately after spreading. The 1987 experiments both lasted 18 days, the 1988 experiments 9 days. A micrometeorological technique, which did not disturb the dynamics of the air flow, was used to measure NH3 volatilization. Volatilization losses were also determined indirectly from mineral-N contents of soil-slurry samples collected at intervals after application. Diurnal fluctuations in the NH3 flux occurred throughout the experimental period, with maxima around midday and minima at midnight. The magnitude of the daily flux values decreased with time. The amounts of N lost through volatilization from surface-applied cattle slurry were 18 and 33% of the total N, resp., during the first 9 days, corresponding to 32 and 67% of the ammoniacal N applied with the slurry. Volatilization was negligible after day 9. Incorporation of the slurry into the soil considerably decreased the loss of N through volatilization: volatile losses of N after 9 days amounted to 6 and 7% of the total N, which corresponds to 11 and 16% of the ammoniacal N applied with the slurry. (Abstract retrieved from CAB Abstracts by CABI’s permission)