The two farming systems (organic and conventional)
studied at farm level in Central Italy has
emphasized interesting differences on soil quality.
It became obvious that organic management affects
soil microbiological and chemical properties by increasing soil nutrient availability, microbial biomass
and microbial activity, which represent a set of sensitive
indicators of soil quality. The microbial biomass
activity was not the only most sensitive reactions to
different management because others soil chemical
properties were affected (i.e. electrical conductivity,
nitrate-N and phosphorus contents). The increased
enzymatic activities in the organically managed soil
expedite mineralization and mobilization of available
nutrients, which may also estimated to be a potential of
eutrophication for adjacent ecosystems. Moreover, in
the two management systems studied, soil properties
linked to available nitrogen (MBN, MBC/MBN ratio
and nitrate) depend variously on seasonal effects. This
is due to the leaching of nitrate caused by seasonal
rainfall. Apparently, in Central Italy, the organic
managed soil needs more than 7 years to improve the
total soil organic carbon content. However, after this
period in the studied area under Mediterranean climatic
regime, the available nutrient content and the microbiological
soil properties resulted early sensitive
indicators of soil quality.