INVESTIGADORES
ZARATE marcelo Aristides
artículos
Título:
Pedosedimentary and palaeoenvironmental significance of a Holocene alluvial sequence in the southern Pampas, Argentina
Autor/es:
MARCELO ZÁRATE; ROB KEMP; MARCELA ESPINOSA; LAURA FERRERO
Revista:
The Holocene
Editorial:
Arnold
Referencias:
Lugar: London ; Año: 2000 vol. 10 p. 481 - 488
ISSN:
1477-0911
Resumen:
resumen
Abstract: A representative section of the Holocene alluvial record of the southern Pampas (Argentina) comprises
a sequence of clastic sediments, a diatomite and two palaeosols. Detailed macro- and micromorphological
descriptions provide the basis for the reconstruction of its pedosedimentary history. Combining the pedosedimentary
reconstruction with palaeoecological data allows a detailed overview of alluvial landscape development
and associated palaeoenvironmental change in the region during the Holocene. The early-Holocene shift from
a subhumid dry to humid climate was marked initially by a diminution in clastic sedimentation, the development
of the Puesto Callejo´n Viejo Soil and then re-establishment of fluvial aggradation with a dominance of bioclastic
sedimentation. Loess inputs increased during the mid-Holocene as the climate reverted to subhumid dry, and
temporary subaerial exposure of the sediments led to the formation of the Puesto Berrondo Soil. More variable
environmental conditions followed with natural fluvial aggradation ceasing in the late Holocene, though aeolian
sedimentation has continued until the present day. The resultant surface accretionary soil has been modified
by recent alluvial inputs from flood events linked to agricultural disturbance in adjacent catchments.A representative section of the Holocene alluvial record of the southern Pampas (Argentina) comprises
a sequence of clastic sediments, a diatomite and two palaeosols. Detailed macro- and micromorphological
descriptions provide the basis for the reconstruction of its pedosedimentary history. Combining the pedosedimentary
reconstruction with palaeoecological data allows a detailed overview of alluvial landscape development
and associated palaeoenvironmental change in the region during the Holocene. The early-Holocene shift from
a subhumid dry to humid climate was marked initially by a diminution in clastic sedimentation, the development
of the Puesto Callejo´n Viejo Soil and then re-establishment of fluvial aggradation with a dominance of bioclastic
sedimentation. Loess inputs increased during the mid-Holocene as the climate reverted to subhumid dry, and
temporary subaerial exposure of the sediments led to the formation of the Puesto Berrondo Soil. More variable
environmental conditions followed with natural fluvial aggradation ceasing in the late Holocene, though aeolian
sedimentation has continued until the present day. The resultant surface accretionary soil has been modified
by recent alluvial inputs from flood events linked to agricultural disturbance in adjacent catchments.