INVESTIGADORES
CAGNOLO Luciano
congresos y reuniones científicas
Título:
ASSESSING PLANT EXTINCTION DEBT IN A FRAGMENTED CHACO SERRANO LANDSCAPE AFTER A DECADE
Autor/es:
AGUILAR, R.; CAGNOLO, L.; AGUIRRE-ACOSTA, N.; ASHWORTH, L.; CALVIÑO, A.; CARBONE, L.
Reunión:
Congreso; Congreso Latinoamericano de Botánica y LXV Congresso Nacional de Botanica; 2014
Resumen:
The
subtropical dry forest of Central Argentina (Chaco Serrano) has suffered the
loss of nearly 95% of its original area during the past 40 years as a result of
the expansion of urban and agricultural boundaries. Today, the Chaco Serrano
forest remains as a fragmented mosaic of forest remnants of different sizes
immersed in highly modified anthropogenic matrices. In a previous floristic
survey conducted in 2003 across a forest fragment-size gradient, we found a
positive and significant plant species ? forest area relationship. In the
present work, we repeat the same floristic survey ten years after (2013). In
April 2013 we conducted identical surveys in the same sites within each of the
18 sampling forest fragments of different size sampled in April 2003. After a
decade, we observed that not only the positive species ? area relationship is
maintained, but also the sampled number of species per site significantly
decreases in all forest fragments, including the larger ones. Moreover, we
observed a relative increase in non-native invasive species richness within the
smaller forest fragments. Thus, after a decade there was an increment in local
species extinction, implying the payment of an extinction debt and an incipient
and progressive invasion of non-native species in smaller remaining forest
fragments. We conclude that the loss and fragmentation of Chaco Serrano forest
caused local extinction debts, that is, the loss of plant species that become
evident only after certain amount of time has elapsed from the original event
of habitat destruction. This is the first work that empirically measures the
extinction debt process in real time within the same fragmented landscape.