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Extreme summer droughts are expected to occur more often in the future in NW Europe due to climate change. These droughts might accelerate the rate of peat oxidation in drained peat areas, with impacts on soil subsidence, GHG emission and water quality. This study aimed at providing more insight in the oxidation of deep peat layers that had not previously been exposed to air, the so-called secondary decomposition. We incubated two types of peat (eutrophic and oligotrophic), sampled from permanently anoxic peat layers from nature reserves and agricultural peat meadows. Peat samples were incubated for thirteen weeks under anoxic conditions, but were exposed to air for one to eight weeks. The production of CO2 and CH4 was quantified as a proxy for decomposition; concentrations of soluble nutrients and phenolic compounds were also measured. The results showed that oxygenation led to a steep increase in the rate of decomposition, indicated by higher carbon loss rates during and after oxygenation compared to non-oxygenated samples. Carbon loss rates increased more for eutrophic peat (agricultural area: 352%, nature reserve: 182%) than for oligotrophic peat (83% and 159% respectively). Most peat samples investigated showed higher post-oxygenation CO2 and/or CH4 production compared to the anoxic pre-oxygenation period. This indicates that oxygenation stimulates decomposition, even after anoxic conditions have returned. Contrary to the enzymic latch theory, no effects of oxygenation on the concentrations of soluble or condensed phenolic compounds were detected. Soluble nutrient concentrations did not change due to oxygenation either. Noteworthy is the occurrence of pyrite mineralization and associated acidification in eutrophic peat. Thus, low summer water levels, for example due to climate change, should be avoided in order to limit exceptionally high decomposition rates and associated problems such as increasing subsidence rates, greenhouse gas emission, sulfate release and acidification.

Extreme summer droughts are expected to occur more often in the future in NW Europe due to climate change. These droughts might accelerate the rate of peat oxidation in drained peat areas, with impacts on soil subsidence, GHG emission and water quality. This study aimed at providing more insight in the oxidation of deep peat layers that had not previously been exposed to air, the so-called secondary decomposition. We incubated two types of peat (eutrophic and oligotrophic), sampled from permanently anoxic peat layers from nature reserves and agricultural peat meadows. Peat samples were incubated for thirteen weeks under anoxic conditions, but were exposed to air for one to eight weeks. The production of CO2 and CH4 was quantified as a proxy for decomposition; concentrations of soluble nutrients and phenolic compounds were also measured. The results showed that oxygenation led to a steep increase in the rate of decomposition, indicated by higher carbon loss rates during and after oxygenation compared to non-oxygenated samples. Carbon loss rates increased more for eutrophic peat (agricultural area: 352%, nature reserve: 182%) than for oligotrophic peat (83% and 159% respectively). Most peat samples investigated showed higher post-oxygenation CO2 and/or CH4 production compared to the anoxic pre-oxygenation period. This indicates that oxygenation stimulates decomposition, even after anoxic conditions have returned. Contrary to the enzymic latch theory, no effects of oxygenation on the concentrations of soluble or condensed phenolic compounds were detected. Soluble nutrient concentrations did not change due to oxygenation either. Noteworthy is the occurrence of pyrite mineralization and associated acidification in eutrophic peat. Thus, low summer water levels, for example due to climate change, should be avoided in order to limit exceptionally high decomposition rates and associated problems such as increasing subsidence rates, greenhouse gas emission, sulfate release and acidification.

This paper assesses the capacity of Whitehouse, Jamaica to adapt to climate change. A community-based vulnerability assessment was conducted that employed semi-structured interviews with community members within or related to the tourism, fisheries and agricultural sectors. The results were analysed using the Local Adaptive Capacity (LAC) framework, which characterises adaptive capacity based on five elements: asset base; institutions and entitlements; knowledge and information; innovation; and flexible forward-looking decision-making and governance. This paper contributes to the literature in three ways. First, it argues that many elements of the LAC framework correspond with an evolutionary perspective on adaptive capacity. Second, it offers an in-depth case study of the capacity of Whitehouse to adapt to climate change. Third, it offers a critical assessment of whether the LAC framework fully captures the important elements of adaptive capacity.

This paper assesses the capacity of Whitehouse, Jamaica to adapt to climate change. A community-based vulnerability assessment was conducted that employed semi-structured interviews with community members within or related to the tourism, fisheries and agricultural sectors. The results were analysed using the Local Adaptive Capacity (LAC) framework, which characterises adaptive capacity based on five elements: asset base; institutions and entitlements; knowledge and information; innovation; and flexible forward-looking decision-making and governance. This paper contributes to the literature in three ways. First, it argues that many elements of the LAC framework correspond with an evolutionary perspective on adaptive capacity. Second, it offers an in-depth case study of the capacity of Whitehouse to adapt to climate change. Third, it offers a critical assessment of whether the LAC framework fully captures the important elements of adaptive capacity.

This document presents a qualitative analysis of surface temperatures of the oceanic territory of Panama. These temperatures represent an indication of the potential of the thermal resource in the oceanic territory of Panama and could generate benefits for the success and stability of the national economy facing the current and growing challenges of the society. The OTEC technology is promising for countries located in tropical regions, where sea temperature differentials are ideal for efficient operability. Currently, this technology has low efficiency levels. Therefore, to evaluate its possible implementation in Panama, a theoretical thermodynamic analysis has been carried out. An organic Rankine cycle (ORC) simulation for the net production of 100KW was performed. It considered the temperature differentials of the oceanography of Panama and used refrigerants R717 and R134a as working fluids. Considering the database of Physical Oceanography Distributed Active Archive Center (PODAAC) for the year 2018, the ocean territory of Panama in the Gulf of Chiriqui reflects seawater surface temperatures (SST) of approximately 27.5 °C to almost 29.5 °C. Besides these values they do not reflect representative anomalies in the critical points with respect to the seasons of the year. The importance of the study in this area is its proximity to the deep cold sea waters, considering the Panama bathymetry map, since its SST are not very variable through the year or through the territory?

This document presents a qualitative analysis of surface temperatures of the oceanic territory of Panama. These temperatures represent an indication of the potential of the thermal resource in the oceanic territory of Panama and could generate benefits for the success and stability of the national economy facing the current and growing challenges of the society. The OTEC technology is promising for countries located in tropical regions, where sea temperature differentials are ideal for efficient operability. Currently, this technology has low efficiency levels. Therefore, to evaluate its possible implementation in Panama, a theoretical thermodynamic analysis has been carried out. An organic Rankine cycle (ORC) simulation for the net production of 100KW was performed. It considered the temperature differentials of the oceanography of Panama and used refrigerants R717 and R134a as working fluids. Considering the database of Physical Oceanography Distributed Active Archive Center (PODAAC) for the year 2018, the ocean territory of Panama in the Gulf of Chiriqui reflects seawater surface temperatures (SST) of approximately 27.5 °C to almost 29.5 °C. Besides these values they do not reflect representative anomalies in the critical points with respect to the seasons of the year. The importance of the study in this area is its proximity to the deep cold sea waters, considering the Panama bathymetry map, since its SST are not very variable through the year or through the territory?

The deep-sea, defined as the area 200 m below the surface, is facing emerging chemical, physical and biological stressors. Currently, very little is known regarding deep-sea ecosystems both globally and in the Arctic. In this thesis I undertook a literature review on the current understanding of global deep-sea ecosystems through the use of stable isotopes. Specifically, I synthesized the available literature on spatial variation, energy pathways, depth, temporal variation, feeding behaviour, niche, trophic position and body size isotopic trends. This thesis then presents a case study examining the isotopic niche of five teleost and two decapod species within Arctic deep-sea food webs across the localized latitudinal gradient of Baffin Island. Spatial variation in isotopic niche was quantified using 13C and 15N for seven deep-sea species at three locations on Baffin Island, Nunavut to determine whether the “Latitudinal Niche Breadth Hypothesis” which states that niche breadth should increase with latitude holds true in the Arctic. Overall, isotopic patterns in global deep-sea ecosystem are variable; consistent trends are not observed across all taxa and habitats. It was concluded that niche breadth did not consistently increase with latitude in the eastern Canadian Arctic; localized conditions (e.g. sea ice, temperature) and individual condition (e.g. hepatosomatic index) may contribute more to a species’ niche than latitude. Overall, this thesis improves our understanding of deep-sea ecosystems globally, contributes baseline data for future monitoring, and by investigating multiple species and locations it will provide input on how climate change may impact Arctic food web diversity, energy dynamics and ecosystem structure to aid in sustainable fishery development.

The deep-sea, defined as the area 200 m below the surface, is facing emerging chemical, physical and biological stressors. Currently, very little is known regarding deep-sea ecosystems both globally and in the Arctic. In this thesis I undertook a literature review on the current understanding of global deep-sea ecosystems through the use of stable isotopes. Specifically, I synthesized the available literature on spatial variation, energy pathways, depth, temporal variation, feeding behaviour, niche, trophic position and body size isotopic trends. This thesis then presents a case study examining the isotopic niche of five teleost and two decapod species within Arctic deep-sea food webs across the localized latitudinal gradient of Baffin Island. Spatial variation in isotopic niche was quantified using 13C and 15N for seven deep-sea species at three locations on Baffin Island, Nunavut to determine whether the “Latitudinal Niche Breadth Hypothesis” which states that niche breadth should increase with latitude holds true in the Arctic. Overall, isotopic patterns in global deep-sea ecosystem are variable; consistent trends are not observed across all taxa and habitats. It was concluded that niche breadth did not consistently increase with latitude in the eastern Canadian Arctic; localized conditions (e.g. sea ice, temperature) and individual condition (e.g. hepatosomatic index) may contribute more to a species’ niche than latitude. Overall, this thesis improves our understanding of deep-sea ecosystems globally, contributes baseline data for future monitoring, and by investigating multiple species and locations it will provide input on how climate change may impact Arctic food web diversity, energy dynamics and ecosystem structure to aid in sustainable fishery development.

Este estágio curricular decorreu no CITEVE, situado em Vila Nova de Famalicão, e teve como principais objetivos a realização da Avaliação de Ciclo de Vida de três produtos da indústria têxtil, com diferentes combinações de matérias-primas: produto 1 (t-shirt com 100% de algodão convencional), produto 2 (t-shirt com 75% de algodão convencional + 25% de algodão reciclado) e produto 3 (t-shirt com 70% de algodão orgânico + 30% de algodão reciclado). Adotou-se uma metodologia “berço-ao-portão” com uma unidade funcional de 1 t-shirt. O trabalho envolveu todas as etapas do processo produtivo, incluindo o transporte, desde a extração e produção das matérias-primas até à produção da t-shirt pronta a enviar ao cliente, deixando de fora as etapas de uso e fim de vida do produto. Para a quantificação dos impactes ambientais, foram selecionadas e analisadas as seguintes categorias de impacte: alterações climáticas, acidificação, eutrofização, depleção fóssil e escassez de água. A avaliação do impacte do ciclo de vida (AICV), foi realizada com o suporte do software GaBi versão 10.6 para calcular os impactes ambientais para cada uma das categorias em estudo. Obtiveram-se os seguintes resultados para os 3 produtos analisados: o produto 1 apresentou 4,30E+00 kg CO2e para as alterações climáticas, 1,88E-02 kg SO2e para a acidificação, 6,95E-04 kg Ne para a eutrofização, 1,37E+00 kgep para a depleção fóssil e 3,56E+01 m3worlde para a escassez de água. O produto 2, para as alterações climáticas apresentou 3,80E+00 kg CO2e, para a acidificação 1,58E-02 kg SO2e, para a eutrofização 5,98E-04 kg Ne, para a depleção fóssil 1,20E+00 kgep e 2,99E+01 m3worlde para a escassez de água. Por sua vez, o produto 3, para as alterações climáticas apresentou 3,64E+00 kg CO2e, para a acidificação 5,83E-03 kg SO2e, para a eutrofização 5,72E-04 kg Ne, para a depleção fóssil 1,14E+00 kgep e para a escassez de água 5,33E+00 m3worlde. A produção de algodão convencional e algodão orgânico constituem-se como uma das fases críticas do ciclo de vida. Para além disto, a utilização de energia elétrica contribui bastante para as categorias das alterações climáticas e da depleção fóssil.