The chemical composition of manure P is a key factor determining its potential bioavailability and susceptibility to runoff. The distribution of P forms in 13 dairy manures was investigated with sequential fractionation coupled with orthophosphate-releasing enzymatic hydrolysis. Among the 13 dairy manures, manure total P varied between 4100 and 18,300 mg kg(-1) dry matter (DM). Water-extractabl...

Phosphorus (P) in animal manure can be an important nutrient for crops or an environmental contaminant if in excess. Organic P in dairy manure may add to the environmentally bioactive P pools upon mineralization. A 353d incubation study of manures containing C:P between 83 and 130:1 was conducted to determine linkages between C and P transformations and the effects of C:P on the immobilization-...

Due to rapid expansion in the poultry industry, production of poultry manure has also consequently increased, resulting in unplanned disposal of this manure to the soil in some cases, with possible negative environmental consequences. In this study, 10 separate poultry manure samples were collected from different sites located in the central Eastern Cape, South Africa and characterized for chem...

Volatilization of ammonia (NH3) from animal manure is a major pathway for nitrogen (N) losses that cause eutrophication, acidification, and other environmental hazards. In this study, the effect of alternative techniques of manure treatment (aeration, separation, addition of peat) and application (broadcast spreading, band spreading, injection, incorporation by harrowing) on NH3 emissions in th...

Three vermicomposts derived from animal manures exposed to the action of the earthworms Eisenia foetida or Lumbricus rubellus were investigated to determine the nature of the humic acid fraction in relation to the potential fertility of the vermicomposts. The isolated humic acid fractions were analysed by pyrolysis-gas chromatography-mass spectrometry. The greater part of the humic acids consis...

An intensive investigation was conducted to study the distribution of trace metals in surface soils of Hong Kong and to assess the soil environmental quality. From results of cluster analysis, and comparisons among soil types and areas, it is clearly shown that increases in trace metal concentrations in the soils were generally extensive and obvious in urban and orchard soils, less so in vegeta...