Die Bodenkultur - Journal for Land Management, Food and Environment

B.P. Bougnom and H. Insam:

Ash additives to compost affect soil microbial communities and apple seedling growth


In this empirical study, we studied the effect of ash admixture to organic wastes as a substrate for composting. In particular, we studied the microbial communities of composts and their potential to improve apple seedling growth.

Amounts of 0 %, 8 % and 16 % ash admixture were used. All composts passed a toxicity test. Eight percent ash admixture to compost induced a shift in bacterial community and enhanced utilisation of all carbon sources (polymers, carboxylic and amino acids, alcohol, and carbohydrates) in a MicroResp™assay, while 16 % ash admixture to compost changed bacterial and fungal communities but did not enhance C utilization. Neither of the composts significantly increased apple seed germination rate or seedling growth. The induced changes in community level physiological profiles and community composition suggest that with a more specific dosage of wood ash and organic wastes, use in apple orchard is possible.

Key words:  Compost, wood ash, Microresp, microbial community, apple seedlings.