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  • ItemAcesso Aberto
    Manuring in Barroso: A crucial farming practice
    1994 - Portela, Ester
  • ItemAcesso Restrito
    As florestas e a conservação da natureza e da biodiversidade no Norte de Portugal
    2011 - Alves, Paulo; Vieira, Cristiana; Helena Hespanhol; Cabral, João Alexandre; Gonçalves, Hélia Vale; Barros, Paulo; Travassos, Paulo; Carvalho, Diogo; Silva, Carmen; Gomes, Carla; Bastos, Rita; Santos, Regina; Santos, Mário Gabriel Santiago dos; Silva, José Manuel Grosso; Caldas, Francisco Barreto
  • ItemAcesso Restrito
    Compensating the Impact of Large Reservoirs in Amphibian Communities: A Case Study
    2014 - Santos, Mário Gabriel Santiago dos; Barros, Paulo; Bastos, Rita; Vale-Gonçalves, Hélia; Lourenço, Vera; Travassos, Paulo; Carvalho, Diogo; Gomes, Carla; Morinha, Francisco; Cabral, João Alexandre
  • ItemAcesso Restrito
    Assessing the Potential Role of Ground Beetles (Coleoptera) As Ecological Indicators in Tropical Ecosystems: A Review
    2015 - Cajaiba, Eduardo; Périco, Eduardo; Cabral, João Alexandre; Santos, Mário Gabriel Santiago dos
  • ItemAcesso Restrito
    17. Anticipating Invasions and Managing Impacts: A Review of Recent Spatiotemporal Modelling Approaches
    2015 - Santos, Mário; Bastos, Rita; Vicente, Joana; Berger, Uta; Silveira Soares Filho, Britaldo; Rodrigues, Hermann; Alonso, Joaquim; Guerra, Carlos; Martins, João; Honrado, João; Cabral, João Alexandre
  • ItemAcesso Restrito
    Simulating the ecological status of changed ecosystems by holistic applications of a new Stochastic-Dynamic Methodology (StDM). Chapter 4.
    2008 - Cabral, João Alexandre; Cabecinha, Edna; Santos, Mário; Travassos, Paulo; Silva-Santos, Pedro
    A new Stochastic Dynamic Methodology (StDM) has been developed as a mechanistic understanding of the holistic ecological processes, by using appropriate statistical and dynamic modelling techniques. Our own recent research is based on the premise that the general statistical patterns of ecological phenomena are emergent indicia of complex ecological processes that do indeed reflect the operation of universal law-like mechanisms. This is the heart of the philosophy of the StDM, a sequential modelling process developed in order to predict the ecological status of changed ecosystems, taking into account stochastic/random phenomena that characterize the real ecological processes. The context of StDM, as we use in this chapter, refers to the application or final use of management models in the scope of programs to measure and monitor ecological integrity. The chapter describes briefly the theory and procedures of StDM, including modelling fundamentals and background statistical methods. It provides a demonstration how StDM can be used to build simple models and will assist the reader and guide the reading process through the examples of holistic ecological applications. In fact, the StDM was successfully tested in several types of ecosystems, such as in changing traditional agricultural scenarios and in some of the environments commonly encountered in water-quality modelling: streams/watersheds, estuaries and reservoirs. In this context, the validation of the obtained simulation results are encouraging since they seem to demonstrate the StDM reliability in capturing the dynamics of the studied ecosystems by predicting the behavioural pattern for the key components selected under very complex and variable environmental scenarios. In summary the ultimate objective of the chapter is encouraging the discussion about holistic methodologies from which management strategies can be designed to restore ecosystems functions and biological communities that have been damaged by anthropogenic disturbances.
  • ItemAcesso Restrito
    The Use of Stochastic Models as a Management Tool in a Shallow Temperate Estuary of South Europe (Mondego, Portugal). Chapter 5.
    2011 - Silva-Santos, Pedro; Lopes, Ricardo Jorge; Múria, Tiago; Medeiros, Joana; Cardoso, Patricia; Dolbeth, Mariana; Pardal, Miguel Ângelo; Cabral, João Alexandre
    A long-term monitoring program has been carried out since the early 1990's in the Mondego estuary, on Portugal's west coast, which is presently under heavy human pressure. Likewise other coastal systems worldwide, the Mondego estuary has been exhibiting clear evidence of eutrophication as a result of nutrient loading from several industries and agricultural run-off, mainly from rice fields. In this shallow warmtemperate estuary, a significant macroalgal proliferation was observed, which represented a clear sign of nutrient enrichment. As a consequence of the eutrophication process, the seagrass meadows (mainly Zostera noltii) almost disappeared, reducing in extent from 15 ha in the early 1980's to 0.02 ha in the mid-1990's. The increase ofmacroalgal biomass and shift of other primary producers resulting from eutrophication had profound effects on estuarine trophic chain. In 1998, some mitigation measures were implemented aiming the recover of the Zostera noltii meadows. The hydraulic regime was improved and nutrient loadings from upstream agricultural areas were minimised due to better management and appropriate sluice handling. Management of coastal and estuarine systems has an increasing need for tools capable to relate environmental variables and system parameters with external factors that affect those systems. In this scope, the need for rapid, standardized and cost-saving assessment methodologies is crucial. This study examined the applicability of stochastic models in predicting the interactions between conceptually isolated key-components, such as primary producers ( macroalgae and seagrass ), some relevant benthic macroinvertebrates, wading birds and changes in local physicochemical conditions. Overall, the simulation results are encouraging since they seem to demonstrate the models reliability in capturing the trophic dynamics of the studied estuary, by predicting the behavioural pattern for the most part of the components selected under very complex and variable environmental scenarios, with a focus on the Zostera noltii meadows recovery after the implementation of important management measures. The ultimate objective is to encourage the discussion about the development and use of stochastic models from which management strategies can be designed to restore coastal ecosystems ftmctions and biological communities that have been damaged by anthropogenic disturbances.
  • ItemAcesso Restrito
    An Outline of Modelling Tool Applications in Freshwater Ecosystem and Resource Management. Chapter 9.
    2013 - Cabecinha, Edna; Cabral, João Alexandre; Hughes, Samantha Jane
    The planet’s aquatic ecosystems have been heavily impacted by broad-scale environmental pressures such as agriculture, point and non point-source pollution and changes in land-use. These multiple environmental impacts overlap in space and time, disrupting ecosystem structure and function, resulting in declining quality of surface water bodies such as rivers and reservoirs. The ecological condition of surface water bodies is dictated by a various factors such as physicochemical parameters, hydrology, geomorphology, habitat and biological quality. Catchments situated in densely populated countries are subject to intense pressures from multiple, often competing soil and water uses. Environmental assessment methods must be able to capture key cause-effect relationships between human activity and ecosystem response in order to contribute to sustainable land use planning decisions and projections of ‘what if’ scenarios at the landscape scale. Modelling techniques have many applications; they can be used in decision asupport systems, as a research tool to predict the outcome of user defined scenarios, to guide management strategies in order to meet future targets and to develop Water Framework Directive (WFD) compliant integrated management frameworks. The studies described in this chapter outline models or methodologies that: (i) Serve as tools to characterize and quantify the effect of different types and levels of disturbance on aquatic ecosystem components; and (ii) The development and implementation of aquatic resource management assessment tools based on these findings. The studies describe and discuss findings from works that use Stochastic-Dynamic Methodology (StDM) coupled with a Cellular Automata (CA) model, to capture how expected or predicted changes in factors such as land use, physicochemical quality and hydromorphology affect the quality of rivers and reservoirs in the Douro region of northeastern Portugal. Results from the studies demonstrate how these techniques provide reliable tools for capturing the stochastic environmental dynamics of selected metrics subject to spatially explicit scenarios. The ultimate goal of the models described in this chapter is to couple monitoring assessment and modelling techniques in order to develop end user tools for WFD compliant management and decision making.
  • ItemAcesso Restrito
    Compensating the impact of large reservoirs in amphibian communities: a case study. Chapter 1.
    2014 - Santos, Mário; Barros, Paulo; Bastos, Rita; Vale-Gonçalves, Hélia; Lourenço, Vera; Travassos, Paulo; Carvalho, Diogo; Gomes, Carla; Morinha, Francisco; Cabral, João Alexandre
    Hydropower, generated mainly from hydroelectric dams, is a renewable energy that provides electricity and helps in reducing carbon emissions. In the Mediterranean region the construction of dams is also considered fundamental for maintaining water supplies during summer, namely for irrigation and domestic consumption. The construction of dams implies the conversion of small temporary streams and ponds into permanent reservoirs. The massive alteration in the hydrologic cycles and associated physical and chemical processes creates new conditions that promote invasive species occurrence and are considered detrimental to the reproduction of most amphibian species. Additionally, the flooding of certain areas affect many important habitats used by adult amphibians and may impose barrier effects to their movement and dispersion. Using a case study in Portugal, the Baixo Sabor Dam, we pretend to outline the implemented steps to compensate impacts on the amphibian communities, namely to the creation of small temporary ponds. The preliminary monitoring results are also analysed and discussed.
  • ItemAcesso Aberto
    Water Use Strategies of Plants Under Drought Conditions.
    2012 - Bacelar, Eunice; Moutinho-Pereira, José; Gonçalves, Berta; Brito, Cátia; Gomes-Laranjo, José; Ferreira, Helena; Correia, Carlos
    The growing concerns about water scarcity have focused more attention on water management in agriculture and promotion of water conservation through improved water use efficiency (WUE). Depending on the main purpose of the study, WUE can be estimated at multiple scales, from leaf to whole plant, crop, yield, and ecosystem levels. Drought resistance and WUE are not synonymous and their association is often misunderstood. Effectively, two water use strategies may be employed by woody plants under drought conditions. The prodigal water use behavior is beneficial in conditions where water supply is interrupted for short periods only. The conservative water use is favorable in conditions where a long dry period prevails and is associated with high capacity for drought resistance and slow growth rates. In this chapter, we also examine how human manipulation such as breeding and agricultural management techniques will offer new opportunities to improve plant water use under drought conditions.