Requalificação e gestão de ribeiras em áreas irrigadas mediterrânicas: aplicação ao perímetro de rega do EFMA

• Author(s): Barbosa, Maria Helena Neves
• Date: 2014
• Persistent ID: http://hdl.handle.net/10400.5/7346
• Origin: Repositório da UTL
• Subject(s): drainage; rehabilitation; streams; ecological functioning; vegetation
• Document Type: Doctoral thesis
• Language: Portuguese
• Advisor(s): Cardoso, Maria Teresa Ferreira da Cunha
• Contributor(s): Repositório da Universidade de Lisboa

Description

Doutoramento em Restauro e Gestão Fluviais - Instituto Superior de Agronomia / Faculdade de Arquitectura / Instituto Superior Técnico

In order to improve the drainage conditions of the several streams located in the Alqueva Multipurpose project, rehabilitation interventions (such as cleaning and reprofiling) are implemented. Little is known about the ecology of this streams, specially the analysis between these interventions' impact and vegetation recovery. Considering the legal requirements of Water Framework Directive, stream rehabilitation effects and overall effectiveness were assessed, and ecological deviations were analyzed between natural and agricultural streams (intervened and not intervened ones). Two types of streams were taken into account, small and large, so as to allow cause-effect relationships. To assess ecological functioning before and after interventions, and also to identify restoration standards between natural and agricultural streams, measurements expressed as categorized variables were performed, as well as statistical tests based on vegetation structure, riparian disturbance and morphological structure variables. The obtained results demonstrated that there are affections in both ecological structure and evolution after small stream reprofiling, as well as small deviations between not intervened and intervened streams and large deviations between agricultural and natural ones. Rehabilitation recommendations for future drainage regarding intervened streams are proposed.