Composta

M. Vukobratović et al.:Composting of wheat straw by using sheep manure
and effective microorganisms

COMPOSTING OF WHEAT STRAW BY USING SHEEP
MANURE AND EFECTIVE MICROORGANISMS
KOMPOSTIRANJE PŠENIĆNE SLAME UPOTREBOM OVČJEG
GNOJA I EFEKTIVNIH MIKROORGANIZAMA
Marija Vukobratović, Z. Lončarić, Ž. Vukobratović,
Ružica Lončarić, H. Čivić
ABSTRACT
A research was conducted into the influenceof effective microorganisms
(EM) and sheep manure on the duration of the process of composting, compost
quality and the cost effectiveness of the process. Physical, chemical and
biological characteristics of initial material and the prepared compost were
analysed. The results of the analysis indicate that 200 days, for how long the
process lasted, is not enough to produce a stable and maturecompost suitable
for use as fertilizer and substrate for production of transplant plants, while the
fertilizer obtained by composting straw mixed with sheep manure and
inoculated with EM is of the highest quality.
Key words: composting, wheat straw, sheep manure, effective microorganisms, maturity
SAŽETAK
Obavljeno je istraživanje utjecaja efektivnih mikroorganizama (EM) i
ovčjeg gnoja natrajanje procesa kompostiranja, kvalitetu komposta i
ekonomsku isplativost postupka. Analizirana su fizikalna, kemijska i biološka
svojstva početnog materijala i gotovog komposta. Rezultati analiza pokazuju da
je 200 dana, koliko je proces trajao, nedovoljno da bi se dobio stabilan i zreo
kompost, pogodan za uporabu kao gnojivo i supstrat za proizvodnju presadnica,
a najkvalitetniji je bio onajdobiven kompostiranjem slame miješane s ovčjim
gnojem i inokulirane EM.
Ključne riječi: kompostiranje, pšenična slama, ovčji gnoj, efektivni
mikroorganizmi, zrelost
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Talk given at the 2nd Mediterranean Conference on Organic Agriculture, Dubrovnik, 2-6 April, 2008

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M. Vukobratović et al.:Composting of wheat straw by using sheep manure
and effective microorganismsINTRODUCTION
In order to make ecological agricultural production successful, it is
necessary to create favourable conditions for quick and unobstructed sprouting
of the seed and fast growth of a plant. Favourable conditions include good
physical, chemical and biological conditions of the medium for plants to strike
root, and can additionally be improved by ploughing harvest residue or byusing
wheat compost (Parr et al, 1990). However, ploughing large quantities of nondisintegrated harvest residue may have undesirable effects on yield, which can
be caused by immobilization of nitrogen in soil, microbiological production or
phytotoxic compounds or by transmitting plant diseases and pathogens (Lynch,
1976, Mathur et al, 1993). These undesirable effects can be prevented bycomposting the material prior to adding it into the soil.
Extensive composting is not profitable due to large loss of carbon and
nitrogen, especially when using straw which could be used as food or raw
material in paper production. In order to shorten the composting process and
reduce the costs, the straw needs to be mixed with manure of high nutritive
value and varied population of microorganisms(Raviv, 1998) and/or treated
with effective microorganisms (EM) (Mupondi et al, 2006). In addition, it is
necessary to monitor majority of chemical and agrobiological parameters of
compost maturity in order to select the optimal way to complete the process
(Blanco and Almendros, 1997). The process has been completed once the
compost is stable and mature. The stability indicates the degree ofdecomposition of organic matter, and shows the microbiological activity and
can be determined respirometrically (Iannotti et al, 1993). Presence or absence
of phytotoxic organic compounds, which can limit plant growth, indicate the
maturity (Zucconi et al, 1981).
The purpose of this paper is:
1) to evaluate the quality of the compost by measuring several parameters of
stability and maturity,...