PARENT SESSION
Tuesday, August 8, 8:00-11:30 am
COS 16 - Disturbance ecology
L-2, Lobby Level, Cook Convention Center
Presiders: S Pathikonda and S Riffell
Biodiversity across a land-use gradient supports the intermediate disturbance hypothesis.
Queiroz, Cibele*,1, Pereira, Henrique1, Vicente, Luís 2, 1 Instituto Superior Técnico, Universidade Técnica de Lisboa, Lisboa, Portugal2 Faculdade de Ciências da Universidade de Lisboa, Lisboa, Portugal
ABSTRACT- Land-use change is recognized as the main driver of biodiversity loss. One of the major trends in European mountain rural areas is agricultural land abandonment. Consequences of abandonment to local biodiversity and ecosystem services remain a controversial issue. We studied plant species diversity across a land use gradient in a mountain agricultural landscape in Sistelo, northern Portugal. Five diferent land use types were selected: cultivated fields, high use pasture areas, low use pasture areas, abandoned fields and native oak forest. A nested sample was performed and local diversity (alpha) and species turnover (beta) were calculated. Species distribution patterns were examined by a Multi Dimensional Scaling (MDS) analysis. Results show that diferences between land uses were significant for both alpha and beta diversity, and diversity was higher for intermediate land uses. These sites are submitted to frequent moderated disturbances and it is suggested that the Intermediate Disturbance Hypothesis can explain this diversity pattern. The effects of agricultural land abandonment on local ecosystem services are not straightforward. While local provisioning services will diminish as well as the cultural services provided by the agricultural landscape, there can be an improvement in the condition of other services like carbon sequestration, soil protection and water cycle regulation.
Key words: Land abandonment, Agricultural ecosystems, Biodiversity