Relationships between humification and productivity in peat-based and peat-free growing media

Abstract

Peat-based and peat-free (compost) materials were tested in a vegetable forcing experiment with Danubia green pepper (Capsicum annuum L.). Stability and quality of humic substances and the turnover of different nitrogen forms was determined in the studied media during the vegetation period. The main objective was to find how the degree of humification might influence the productivity of a crop under greenhouse conditions. The highest humus stability and humus stability coefficient values were detected in the green waste compost. Among different peat media, the low-moor peat was more humificated than the mixture of low-moor and high-moor peat. When the medium is more humificated it has a larger mobile nitrogen reserve. However, the structure stability decreases with the increasing humification. The mixture of two types of peat had the most favourable effect on nitrogen supply and the yield of pepper was the highest when grown on this medium. The nitrogen supplying ability of the examined compost was excellent but its structure stability deteriorated during the growing season.

Keywords

• compost
• green pepper
• humification
• nitrogen
• peat