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- Biogeochemical Modelling of Ria Formosa (South Portugal)Publication . Duarte, Pedro; Azevedo, Bruno; Guerreiro, Maria; Ribeiro, Catarina; Bandeira, Rui; Pereira, António; Falcão, Manuela; Serpa, Dalila; Reia, João; yesRia Formosa is a large (c.a. 100 km2) mesotidal lagunary system with intertidal areas with conflicting uses such as fisheries, aquaculture, tourism and nature conservation. Its watersheds cover an area of approximately 864 km2, with a perimeter of 166 km and a maximum altitude of 522 m. Land use may be classified into six major groups: 1) urban, 2) agricultural, 3) forest, 4) rangeland and pastures, 5) wetlands and 6) water bodies. The main objectives of this work are to: (i) Evaluate the relative importance of land drainage, waste water treatment plants (WTP) and water exchanges across the lagoon inlets, for nutrient dynamics; (ii) Analyse management scenarios related to changes in lagoon bathymetry and their potential effects on system dynamics. The Soil and Water Assessment Tool (SWAT model) has been applied to the catchment areas in order to simulate water discharges into Ria Formosa providing forcing to a twodimensional vertically integrated coupled physical-biogeochemical model, implemented with EcoDynamo – an object oriented modelling software. This model includes water column and sediment processes as well as their interactions and several biological sub-models (e.g. phytoplankton dynamics and bivalve growth). Obtained results suggest that the river network may have a significant effect on lagoon concentrations, in spite of the relatively low river flows, due to the high ammonium and nitrate loads. Scenarios reflecting increases in lagoon bathymetry through dredging operations suggest an increase in lagoon water washout time with potential impacts on water quality and impacts at a scale of tens of km. The obtained results are being used by the Ria Formosa Natural Park authority for management purposes and may be useful to feedback future updates of the watershed management plans, within the scope of the European Union Water Framework Directive. The use of a lagoon scale models is therefore justified in this work
- EcoDynamo - Ecological Dynamics Model ApplicationPublication . Pereira, António; Duarte, Pedro
- Hydrodynamic Modelling of Ria Formosa (South Coast of Portugal) with EcoDynamoPublication . Duarte, Pedro; Azevedo, Bruno; Pereira, AntónioIn this work a hydrodynamic model of Ria Formosa (South of Portugal) is presented. Ria Formosa is a large (c.a. 100 km2) mesotidal lagunary system with large intertidal areas and several conflicting uses, such as fisheries, aquaculture, tourism and nature conservation. This coastal ecosystem is a natural park where several management plans and administrative responsibilities overlap. The work presented here is part of a coupled hydrodynamicbiogeochemical model that includes pelagic and benthic processes and variables. It is a two-dimensional vertically integrated hydrodynamic model, based on a finite differences grid with a 100 m spatial step and a semi-implicit resolution scheme. It is forced by tide level changes at the sea boundary and river flows at the land boundary. The model includes a wetdrying scheme to account for the dynamics of the large intertidal areas. The purposes of this work are to: (i) describe the model; (ii) present its calibration and validation against field data; (iii) use the model to analyse circulation patterns and estimate the water residence time and (iv) analyse the dispersion of effluents rejected by the Waste Water Treatment Plants located in the lagoon.
- A Geographical Information System for Ria Formosa (South Coast of Portugal)Publication . Rodrigues, Ana; Carvalho, António; Reia, João; Azevedo, Bruno; Martins, Cláudia; Duarte, Pedro; Serpa, Dalila; Falcão, Manuela
- Biogeochemical Modelling of Ria Formosa (South Coast of Portugal) with EcoDynamo - Model descriptionPublication . Duarte, Pedro; Pereira, António; Falcão, Manuela; Serpa, Dalila; Ribeiro, Catarina; Bandeira, Rui; Azevedo, Bruno
- Scenario Analysis in Ria Formosa with EcoDynamoPublication . Duarte, Pedro; Azevedo, Bruno; Ribeiro, Catarina; Pereira, António; Falcão, Manuela; Serpa, Dalila; Bandeira, Rui; Reia, JoãoRia Formosa is a natural park managed partly by the Portuguese end-users of the DITTY project – Ria Formosa Natural Park authority, under “Instituto para a Conservação da Natureza (ICN)”. There are many conflicting interests over the management of this important coastal area: fishing, tourism, aquaculture, salt production, harbour activities, urban development and conservation. Furthermore, several institutions, such as the Natural Park Authority, municipalities, the Portuguese Navy, just to mention a few, are involved in decision-making over several areas of the natural park. Within DITTY, several scenarios were selected among those relevant for the management of this coastal ecosystem, considering available information from the end-users, relative importance of the mentioned scenarios, modelling and time constraints.
- DSS Application (Ria Formosa Lagoon)Publication . Pereira, António; Duarte, PedroThis report presents the Decision Support System (DSS) applied to the Ria Formosa lagoon using an agent-based simulation approach. The idea is to include the interests of the decision-makers and stakeholders in the ecological system simulation; these entities are modelled as intelligent agents that communicate with the simulation tool (EcoDynamo) building one multi-agent community system. The intelligent agents, each one with some goals about the simulation results of the simulated system, have perception of their environment, reason, using their knowledge and are able to change the simulated environment by using a given set of configurable actions. Two intelligent agents are being developed at the moment: one calibration agent and one aquaculture/farming agent. The former intends to optimise the fit between observed and simulated results, and the latter looks for production optimisation. The agent used to generate this report is a development tool that includes actions from both agents. This report also introduces ECOLANG, a communication language developed during the DITTY project, with the main purpose of interchanging information between the simulation application of aquatic ecosystems - EcoDynamo - and external agents. Finally, the report focuses on the integration of the Analytical Hierarchy Process (AHP), developed by the University of Siena, in the aquaculture/farming agent decision process (Siena 2005 and Siena 2006)
- ECODOURO - Modelling the effect of freshwater reduction and pulse discharge on the water dynamics and processes of the Crestuma ReservoirPublication . Bordalo, Adriano; Duarte, Pedro; Wiebe, WilliamThis report deals with the activities carried out during the project 72 months, from March 15, 2003 to September 15, 2006 under the framework of the ECODOURO - Modelling the effect of freshwater reduction and pulse discharge on the water dynamics and processes of the Crestuma Reservoir (POCTI/MGS/45533/2002). The report includes the fieldwork, data interpretation and mathematical modeling according to the seven working packages presented in the original proposal. Data is available to the public at http://ecodouro.icbas.up.pt. The main objectives of this goal oriented research project implemented on the Crestuma Reservoir (Douro River) are: i. To evaluate the long-term effects of flow reduction on key environmental variables and processes that occur in the Crestuma Reservoir; and ii. To evaluate the effect of high frequency oscillations (freshwater pulse discharges) on the ecosystem dynamics in terms of water column stratification, water temperature and turbidity, oxygen, nutrient availability, phytoplankton biomass and primary productivity. The original requested budget was reduced by 19%, and the evaluation commission recommended the non-acquisition of a second multiprobe CTD. Thus, the entire field survey program was changed accordingly. The seasonal sampling was conducted at two anchor stations located about 500 m and 2,500 m from the Crestuma dam crest. Surveys were performed on December 2003 (Fall), February 2004 (Winter), May 2004 (Spring) and August 2004 (Summer). An un-scheduled survey was carried out at the onset of the program (May 2003), in order to gather basic data since no departure data (short term series) were available contrarily to what was though. This approach proved to be very useful and the obtained results were applied in the following surveys. Moreover, since no workable bathymetrics were available to the research team (only depth contours in chart format restricted to the navigational channel) several dedicated surveys were organized in order to generate bottom contour maps for the last 10 km of the reservoir, covering the two-field stations location. As a result, a costume-made GIS was created and data used to run the model. All technical details of both the employed models (2D-vertically resolved model and the coupled biogeochemical model), including the complete mathematical formulae, are 2 presented in Annexes I and II. The rationale for selection of the modeled parameters are presented; the field data obtained from the 4+1 surveys were used to initialize the models. It was found that the different flow time-scales might influence water dynamics, biogeochemistry and primary productivity. For example, during the day, longitudinal flows results from upstream forcing, with river water entering into the reservoir. A clear longitudinal flow profile emergeed, disturbed in some points by depth changes that forces upwelling of bottom water. During the night, in the absence of river flow, at it happens frequently in Spring through Fall, convective flow dominated, with surface cooled water sinking to the bottom and forcing the ascent of bottom water. Vertical flows may be larger than horizontal ones. On the other hand, the highest phytoplankton production was observed in May and September, when microalgae were using more efficiently the available light. Furthermore, phytoplankton efficiency decreased from morning to dawn. Considering the objectives of this project, several model simulations were carried out to analyze the effects of flow variability on water column stratification and quality (cf. – Annexe III). These simulations were carried out with the same average flow magnitude and forcing conditions, in terms of water temperature, nutrients and chlorophyll concentrations, but different flow frequencies and amplitudes. Results obtained suggest that flow variability may not have a large effect on water temperature, nutrient and chlorophyll concentration and net primary production at annual time scales. However, when the time scale under analysis is reduced to seasonal and monthly, effects of flow variability become apparent, especially during the summer period and when flow is hold constant. Constant flow implies that extreme low and high values do not occur. Under this situation of “extreme” flow regulation, it appears that the synergies between river forcing and reservoir processes tend to reduce phytoplankton biomass. Therefore, from a management point of view, it is apparent that stabilizing the flow may prevent the development of phytoplankton blooms. On the other hand, results presented and discussed in Annex IV suggest that the Crestuma reservoir has undergone some important changes over the period 1999-2005, with significant increases in nitrogen and phosphorus and a decrease in the nitrogen: phosphorus ratio i.e. the Redfield ratio. One possible change, arising from the shifts in the nitrogen: phosphorus ratio, is the apparent autumn shift towards nitrate-nitrogen limitation of phytoplankton. Apart from increasing nutrient runoff within the watershed, the 3 noticeable nutrient increase trend found in the Crestuma resevoir may also be explained by the reduction of chlorophyll as a result of the massive development of the invasive clam Corbicula sp. Thus, the Crestuma reservoir is now a predominantly heterotrophic ecosystem that is the source of water to 20% of the Portuguese population and feeds the Douro estuary with most of the water that reaches the Atlantic Ocean. As a result of this project, a full functional calibrated with dedicated data model is available. During the 72 mo of the project, three young researchers were able to work and get training in the different areas covered by the program. Due to the enormous amount of data gathered, only two research papers were published. Thus, in the near future, two papers will be submitted (as a result of Annex III and Annex IV), and two additional papers are under preparation. Part of the obtained data has being used for teaching purposes at undergraduate and Master/PhD levels by the PI and the Cemas team.