Agriculture is a human activity essential for society, for all level of development. The
big question today is how to keep it productive without dramatically affecting the
various terrestrial ecosystems. Soil can be considered the basis for sustaining
agricultural systems. Thus, losses in properties, which reduce the ability to sustain
plant growth or that involve risks, negative impact of great significance to rural
communities, with repercussions on the urban environment. Among the factors that
make the land productive and unsustainable in environmental terms, is the use of fire
as a way of cleaning the areas for implementation of agricultural crops. The fire, one
of the oldest technologies incorporated into production systems, is used to this day,
for easy cleaning of the area and make the nutrients readily available to the
vegetation stage of cultivation, through the ashes. Nevertheless, it is major problem
due to its negative effects. It was within this context that a group of farmers under the
articulation of a regional organization, the Foundation Live, Produce and Preserve,
decided to begin an experiment aimed at testing practical implementation of
agricultural system without using fire, intending to maintain soil fertility . These
alternative systems, so-called "Roca Without Burning," are characterized by the
implementation of agroforestry systems based on the principles of agroecology. This
study seeks to understand how these "systems of farm without burning, can influence
the maintenance of sustainability of the soil, its ability to perpetually harvest and
renewal of biomass systems. For both, were studied as indicators of sustainability of
some attributes related to soil organic matter and soil microbial biomass, because
there is a growing perception consider them indicators of sustainability. Soil samples
were made in the municipalities of Medicilândia Uruará and at the end of the dry
season, January 2005, at depths 0-5, 5-10, 10-20 and 20-30. The systems were
chosen to be monitored as the main component of cocoa to be an economically
important crop in the Tran-region. The results showed that the stock of litter in soil
microbial biomass carbon, soil organic carbon and total nitrogen, basal respiration
and derived indices (ratio organic carbon / total nitrogen, compared microbial carbon
/ organic carbon and metabolic quotient pain indicators studied are not sensitive to
changes in soil management system. The data support the idea that the
agroecosystems of "slash without burning," are capable of storing large amounts of
organic material, with a tendency for carbon storage and maintenance of fertility soil,
making it therefore a promising agricultural practice for the development of family
farming on a sustainable basis
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