INVESTIGADORES
GOLLUSCIO Rodolfo Angel
artículos
Título:
Effect of cattle grazing on soil salinity and vegetation composition along an elevation gradient in a temperate coastal salt marsh of Samborombo´n Bay (Argentina)
Autor/es:
DI BELLA, C.; JACOBO, E.; GOLLUSCIO, R.A; A. RODRIGUEZ
Revista:
WETLANDS ECOLOGY AND MANAGEMENT
Editorial:
SPRINGER
Referencias:
Lugar: Berlin; Año: 2013
ISSN:
0923-4861
Resumen:
Salt
marshes of Samborombo´n Bay (Argentina)
have been grazed sporadically at very low stocking rates, but in the last
decade, grazing intensity increased due to agriculture expansion. We investigated
the effect of cattle grazing on vegetation and soil salinity on the most
extended Spartina densiflora community. This community develops along an
elevation gradient where the frequency and duration of tidal flooding and soil
salinity increased as elevation decreased. Vegetation and soil data were collected
from a national park excluded to cattle grazing for 30 years and from an
adjacent commercial livestock farm continuously grazed by cattle. As elevation
level decreased, plant cover, richness and diversity of functional groups and
species decreased. As we expected, grazing altered soil salinity and vegetation
composition in different extent along the elevation gradient. Grazing changed
vegetation structure more intensively in the high elevation level because it
reduced the competitive exclusion exerted by S. densiflora, allowing the
increase in floristic richness. Grazing increased soil salinity and the contribution
of salt-tolerant species only in the medium but not in the low elevation level
probably because the higher frequency and duration of tidal flooding
counterbalanced the increase in evaporation promoted by biomass removal in the
low respect to the medium elevation level. While grazing may cause positive
impacts for plant conservation in the high elevation level, it may cause
negative consequence for livestock production because of the reduction in forage
quality along the entire elevation gradient.