INVESTIGADORES
MARTINEZ PASTUR guillermo Jose
artículos
Título:
Silvopastoral use of Nothofagus antarctica in Southern Patagonian forests, influence over net nitrogen soil mineralization.
Autor/es:
HA BAHAMONDE; PL PERI; R ALVAREZ; A BARNEIX; A MORETTO; G MARTÍNEZ PASTUR
Revista:
AGROFORESTRY SYSTEMS
Editorial:
SPRINGER
Referencias:
Lugar: Berlin; Año: 2013 vol. 87 p. 259 - 271
ISSN:
0167-4366
Resumen:
In most temperate forest, nitrogen (N) is
considered a limiting factor. This becomes important
in extreme environments, as Nothofagus antarctica
forests, where the antecedents are scarce. Thinning
practices in N. antarctica forests for silvopastoral
uses may modify the soil N dynamics. Therefore, the
objective of this work was to evaluate the temporal
variation of soil N in these ecosystems. The mineral
extractable soil N, net nitrification and net N mineralization
were evaluated under different crown cover
and two site quality stands. The mineral N extractable
(NH4
?N ? NO3
-N) was measured periodically.
Net nitrification and net N mineralization were
estimated through the technique of incubation of
intact samples with tubes. The total mineral extractable
N concentration varied between crown cover
and dates, with no differences among site classes. The
lowest and highest values were found in the minimal
and intermediate crown cover, respectively. In the
higher site quality stand, the annual net N mineralization
was lower in the minimal crown cover reaching
11 kg N ha-1 year-1, and higher in the maximal
crown cover (54 kg N ha-1 year-1). In the lower site
quality stand there was no differences among crown
cover. The same pattern was found for net nitrification.
Thinning practices for silvopastoral use of these
forests, keeping intermediate crown cover values,
did not affect both N mineralization and nitrification.
However, the results suggest that total trees removal
from the ecosystem may decrease N mineralization
and nitrification.