Simulation of economic benefits achieved by water quality improvement for recreational and professional users, within the SPICOSSA SSA (SPICOSSA System Approach) 11 - Guadiana estuary ecosystem sic

Dissertação de Mestrado, Gestão da Água e da Costa, Faculdade de Ciências e Tecnologia, Universidade do Algarve, 2010

Cape Verde coastal ecosystem: a study of community structure, trophic interactions and exploitation pattern

Tese de dout., Ciências e Tecnologia das Pescas, Faculdade de Ciências do Mar e do Ambiente, Universidade do Algarve, 2005

The economic effects of common agricultural policy on Mediterranean montado/dehesa ecosystem

The decoupling of CAP payments leads production decisions and resources allocation to be more dependent on market prices and competitive advantages. The objective of this paper is to assess the effects of CAP trends on the montado/dehesa traditional ecosystem of Mediterranean regions in terms of farm income, land, labour and capital. A positive mathematical supply model disaggregated by the montado agro-forestry production systems of the Alentejo region in southern Portugal is developed. The results show that decoupling payments of CAP have negative economic effects on agricultural activities and resource use. Agricultural income increases with single farm payments but the foreseen increases in prices do not compensate the loss of the Agenda 2000 area payments in terms of competitiveness. These results reinforce the need to promote alternative agricultural and non-agricultural activities and policies in Mediterranean rural European areas and regions. (C) 2011 Society for Policy Modeling. Published by Elsevier Inc. All rights reserved.

Ecologically relevant characteristics of flow-regime of Rufiji Basin in Tanzania (an ensemble of ecohydrological clues to infer associeted ramifications on dtream and ecosystem)

Dissertação de Mestrado, Ecohidrologia - Erasmus Mundus, Faculdade de Ciências e Tecnologia, Universidade do Algarve, 2014

Trophic food web and ecosystem attributes of a water reservoir of the Ria Formosa (south Portugal)

Using a top-down modelling approach, a balanced trophic food web model of a water reservoir of the Ria Formosa lagoonal system was constructed. Few adjustments of input data were necessary to run the model since most of the parameters were estimated at the study site and the characteristics of the water reservoir allowed a high degree of control and precision in terms of sampling and data collection. Trophic levels of the 14 compartments included in the model varied between 1.0 for primary producers and detritus to 3.4 for carnivorous fish and the 14 groups were aggregated in a food chain with six trophic levels. The water reservoir has a detritus based food chain, with the majority of the biomass concentrated in the first two levels, the producers level and the herbivore/detritivore level (97.6%). The transfer efficiencies were low, and decreased with increasing level number, varying between 6.0 and 0.2%. The degree of "ecosystem maturity" was difficult to establish, but several parameters indicate that it could be high. The water reservoir studied, which has similar environmental and ecological characteristics as the Ria Formosa lagoon. is near its carrying capacity. (C) 2004, Elsevier B.V. All rights reserved.