TERCEIRÂ REUNIÄO BRASILEIRA CIENCIA DO SOLO

ANAIS DA TERCEIRA REUNIÂO BRASILEIRA DE CIÊNCIA DO SOLO 173
tore concerning the fractionation of organic matter and the resistence
of the compounds thus obtained to the decomposition by microorganisms,
it was advanced the idea of an approximatly equal rate of decomposition
for all the fraction for this soil type with the exception
of the nitrogen compounds and water extract compounds.
The fractionation of organic nitrogen compounds indicates enrichment
of protein content in the soil with depth. It was determined o
that the losses of non nitrogen constituents were higher than those "
of nitrogen compounds. The accumulation of the latter in the soil
takes place in the form of protein and related compounds.
The C/N ratio falls frqm 20 to 30 in the L layer to 10 to 14 in the
layer a raizing in b and c layers which shows a definite washing of non
nitrogen organic compounds in to these horizons.
LITERATURA CITADA
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