Innovative biocatalytic production of soil substrate from green waste compost as a sustainable peat substitute

In the present work, a new simple and quick eco-friendly method is discussed to handle effectively the green wastes and produce a sustainable peat substitute of high quality on the large scale. Principal physicochemical parameters, i.e., temperature, moisture, specific weight, pH, electrical conductivity and, also, microorganisms, organic matter, humic substances, total Kjeldahl nitrogen and total organic carbon, C/N ratio, ash, metal content and phytotoxicity, were monitored systematically. Humic substances content values were interrelated to both C/N ratio and pH values and, similarly, bulk density, TOC, TKN, C/N, GI, ash and organic matter were found interconnected to each other. A novel biocatalyst, extremely rich in soil microorganisms, prepared from compost extracts and peaty lignite, accelerated the biotransformation. Zeolite was also employed. The compost does not demonstrate any phytotoxicity throughout the entire biotransformation process and has increased humic substances content. Both humic substances content and germination index can be employed as maturation indices of the compost. Addition of compost, processed for 60 days only, in cultivations of grass plants led to a significant increase in the stem mass and root size, annotating the significant contribution of the compost to both growth and germination. The product obtained is comparable to peat humus, useful as peat substitute and can be classified as a first class soil conditioner suitable for organic farming.