Bioavailability and Solubility of Heavy Metals and Trace Elements during Composting of Cow Manure and Tree Litter

Table 1

Raw materials for composting used in the investigation stages.

Stage	Type of compost	Raw material	Quantity in compost pile (kg)	Proportion (%)	Composting time (days)
Characterization	Co-compost of cow manure and grass clipping	Cow manure	200	40	111
		Grass clipping	300	60
	Compost of tree litter	Tree litter	3000	100	240
Evaluation	Co-compost of cow manure and tree litter IBM	Cow manure	240	40	120
		Tree litter	360	60
	Co-compost of cow manure and tree litter NBM	Cow manure	240	40	120
		Tree litter	360	60