Agriculture Reference
In-Depth Information
regulations include parameters related to the process monitoring that have to be
respected. Among the others, the most used parameter is the number of days over a
threshold temperature (55, 60 or 65 °C) achieved in the composting mass.
According to EU regulations (EC 889/07; 834/08) in organic farming one can
use every kind of compost excluding the sewage sludge based compost. Compost
from municipal solid waste are permitted in any case, however, its quality increases
in case compost was prepared from the organic separated collection of the urban
wastes especially when the organic fraction is source-separated or comes from
door-to-door collection (Richard and Woodbury
1992
). National regulations or pri-
vate standards can be more restrictive or specific in terms of compost definition and
its use in organic farming. It is worth noting that the composting business is based
on waste recycling much more than compost commercialization. The raw materials'
rate in the starting mixture is decided according to the economical values of each
waste that could be accepted as input to the facility (usually those are in order: sew-
age sludge, other sludge, municipal solid waste, other urban waste like public green
pruning). The most profitable waste amount in the starting mixture is set to the
maximum rate, which could warranty final compost acceptable under the law limits.
1.2.4
On-farm Composting: An Agroecological Practice
On contrary to commercially produced composts, the on-farm compost possibly
presents higher organic C content and high level of humus-like substances compared
to the mean values generally reported on commercial compost's labels. Unfortu-
nately, this is accompanied with a slower mineralization rate of the on-farm compost
in comparison with those of commercial products due to the high content of lingo-
cellulosic residues, which are generally used in the on-farm composting preparation.
At farm level any products resulted from the on-farm composting process could be
used as soil amendment inside the same farm area without any law constrictions.
This does not guarantee that compost produced by the farmer will have better char-
acteristics than commercial compost available on the market. Specifically, in organic
farms it is possible to assume that the raw materials available presents lower content
of heavy metals, antibiotics and pesticides residues than the raw materials used in
commercial composting plants. Again, this does not mean that the farmers' know-
how and the composting facilities available in loco will be enough to prepare the
appropriate mixture and to manage the composting process at the best.
1.3
Composting: Feed Microorganism to Produce
Compost
The composting process includes four phases: (i) initial mesophilic phase (up to
42 °C), which lasts for few hours after the pile formation and it is strongly influ-
enced by raw materials characteristics and storage conditions; (ii) thermophilic
