期刊名称：Beiträge aus der Nordwestdeutschen Forstlichen Versuchsanstalt
印刷版ISSN：1865-6994
出版年度：2006
卷号：1
页码：60-60
出版社：Universitäts-Verlag Göttingen
摘要：The interactions occurring between biochemical composition of plant residues and
placement in soil were assessed by studying the C and N biotransformation of different
tissues of Solanum melongena L. (roots, leaves and fruit). The plant residues, in which
the C/N ratio varied between 25 and 11, were homogenously labelled with 15N. The
grounded residues were placed either on the surface or as a layer in the soil column, or
was homogenised with soil. The decomposition was studied during 60 days laboratory
incubation at 15 ¡ãC and optimal water content. The CO2 evolution was continuously
measured, the inorganic N and microbial biomass was determined before and after the
incubation. The residue placement significantly influenced the cumulative respiration,
but did not significantly affect the apparent N mineralization and microbial quotient.
The microbial biomass C and N was higher for the homogenised treatment than for the
surface amendment; however this effect only was significant for the fruits. Fruits and
leaves showed the highest proportion of not mineralised residue-C during the layer
placement smallest during surface application, this effect was not found for the roots.
The net flux of substrate-N was determined by the 15N tracing technique. More intimate
soil contact resulted in higher allocation of residue-N in the microbial biomass for roots
and fruits; leaves did not show this effect. Neither had the different placements any effect
on net substrate-N mineralization. Significant correlation was found between apparent
N-mineralization and net substrate-N-fluxes. In contrast the C and N fluxes were
not or only weakly correlated.
