INVESTIGADORES
VILLAGRA Pablo Eugenio
congresos y reuniones científicas
Título:
Spatial patterns of soil moisture and nitrate as a function of distance from the livestock corrals in the monte desert
Autor/es:
MEGLIOLI, P.A.; VILLAGRA, P.E.; ARANIBAR, J.N.
Reunión:
Congreso; XXX Reunión Anual de la Sociedad de Biología de Cuyo; 2012
Institución organizadora:
Sociedad de biología de Cuyo
Resumen:
In the Monte desert, livestock settlements generate environmental
grazing gradients and represent an opportunity to study the effects
of grazing pressures on spatial patterns of nutrients and water. In
such context, we expected these spatial patterns be modified, both
horizontally and vertically, as a function of distance from livestock
corrals. We analyzed nitrate and water contents and salinity (electrical
conductivity) on six linear transects (65 to 75 m along) corresponding
to three livestock stations (LS) and three undisturbed
control woodlands (CW). On each transect, we sampled soil profiles
(up to 200 cm depth) every 5 m. In the initial, middle and
final points of each transect, we collected soil samples from up to
400 cm depth. Transects in the LS began in a corral, whereas those
in the CW began at the bottom of the valley. Nitrate and water
contents in all depth intervals were greater at the LS than at the
CW. Horizontal distribution patterns in LS showed a negative relation
of water, nitrate, and conductivity with distance from the corrals.
CW did not show a relation of these variables with distance
from the valley bottom. This pattern was evident for surface soils.
Conductivity was lower in the LS, although the topsoil of corrals
had the highest values compared to the CW soils. Our results demonstrate
that LS produce biogeochemical soil changes, causing a
centripetal pattern of nitrate, water, and salt accumulation in the
vicinity of the corrals.