Woody plant-cover dynamics in Argentine Savannas from the 1880s to 2000s : the interplay of encroachment and agriculture conversion at varying scales
Date
2015
Journal Title
Journal ISSN
Volume Title
Publisher
Springer
Abstract
Woody plant-cover dynamics can alter the provisioning
of ecosystem services that humans rely on.
However, our understanding of such dynamics
today is often limited by the availability of reliable
and detailed land-cover information in the past,
before the onset of remote sensing technologies. In
this study, we carefully extracted information from
historical maps of the Caldenal savannas of central
Argentina in the 1880s to generate a woody cover
map that we compared to a 2000s dataset. Over
about the last 120 years, woody cover increased
across approximately 12,200 km2 (14.2% of the
area). During the same period, about 5,000 km2 of
the original woody area was converted to croplands
and around 7,000 km2 to pastures, about the same
total land area as was affected by encroachment. A
smaller area, fine-scale analysis between the 1960s
and the 2000s revealed that tree cover increased overall by 27%, shifting from open savannas to a
mosaic of dense woodlands along with additional
agricultural clearings. Statistical models indicate
that woody cover dynamics in this region were
affected by a combination of environmental and
human factors. Over about the last 120 years,
increases in woody plant cover have stored significant
amounts of C (95.9 TgC), but not enough to
compensate for losses from conversions to croplands
and pastures (166.7 TgC), generating a
regional net loss of 70.9 TgC. C losses could be even
larger in the future if, as predicted, energy crops
such as switchgrass, would trigger a new land-cover
change phase in this region.
Description
item.page.type
Journal Article (peer-reviewed)
item.page.format
Keywords
PROSOPIS CALDENIA, WOODY PLANTS, DEFORESTATION, AGROECOLOGY, SEMIARID ZONE, ARGENTINA, LAND MANAGEMENT, CARBON STOCK ASSESSMENTS, LAND USE, ENVIRONMENTAL DEGRADATION, MAPS, SAVANNAS
Citation
González-Roglich, M., Swenson, J.J., Villarreal, D., Jobbágy, E.G., & Jackson, R.B. (2015). Woody Plant-Cover Dynamics in Argentine Savannas from the 1880s to 2000s: The Interplay of Encroachment and Agriculture Conversion at Varying Scales. Ecosystems, 1-12. doi:10.1007/s10021-015-9841-5