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L'aquaculture joue un rôle important dans la sécurité alimentaire et fournit des moyens de subsistance et des emplois à des millions de personnes dans les communautés côtières du monde entier. Cependant, le secteur aquacole en pleine croissance a également suscité des débats sur sa durabilité écologique à long terme, sa viabilité économique, les inégalités sociales potentielles et les problèmes de gouvernance. Nous avons étudié les défis et les opportunités perçus pour parvenir à une aquaculture durable du crabe de boue dans les régions côtières tropicales en utilisant l'étude de cas des fermes côtières de crabe de boue dans l'Andhra Pradesh, en Inde. Sur la base des perceptions et des données financières indicatives d'un échantillon de parties prenantes, nous avons étudié les résultats économiques potentiels dans différents scénarios représentant des niveaux de rendement, des facteurs de risque et des périodes de projet variables. Les principaux risques identifiés par les parties prenantes étaient associés à l'approvisionnement limité en graines de crabe de boue et au manque d'accès aux programmes de soutien gouvernementaux et non gouvernementaux. Il n'y a pas de tampons financiers, donc des épidémies majeures ou des conditions météorologiques extrêmes causées par le changement climatique entraîneraient une perte de moyens de subsistance. Cet article met également en évidence le facteur le plus critique déterminant le niveau de succès de l'élevage du crabe de boue étant le taux de survie du crabe qui est influencé par une variété de facteurs, y compris l'augmentation de la température de la surface de la mer. Les résultats de cette étude montrent que l'élevage de crabes de boue à petite échelle comporte moins de risques et une plus grande flexibilité que l'élevage de crabes de boue à grande échelle. Il pourrait s'agir d'une entreprise économiquement durable et servir d'outil de réduction de la pauvreté dans les pays en développement si un soutien et une formation en matière de microfinance sont disponibles. La acuicultura desempeña un papel importante en la seguridad alimentaria y proporciona medios de subsistencia y empleo a millones de personas en las comunidades costeras de todo el mundo. Sin embargo, el creciente sector de la acuicultura también ha creado debates en torno a su sostenibilidad ecológica a largo plazo, viabilidad económica, posibles desigualdades sociales y problemas de gobernanza. Investigamos los desafíos y oportunidades percibidos para lograr una acuicultura sostenible de cangrejo de fango en las regiones costeras tropicales utilizando el estudio de caso de las granjas costeras de cangrejo de fango en Andhra Pradesh, India. Con base en las percepciones y los datos financieros indicativos de una muestra de partes interesadas, investigamos los posibles resultados económicos en diferentes escenarios que representan diferentes niveles de rendimiento, factores de riesgo y períodos de tiempo del proyecto. Los principales riesgos identificados por las partes interesadas se asociaron con el suministro limitado de semillas de cangrejo de fango y la falta de acceso a esquemas de apoyo gubernamentales y no gubernamentales. No hay amortiguadores financieros, por lo tanto, los grandes brotes de enfermedades o las condiciones climáticas extremas causadas por el cambio climático conducirían a la pérdida de los medios de vida. Este documento también destaca que el factor más crítico que determina el nivel de éxito del cultivo de cangrejo de fango es la tasa de supervivencia del cangrejo, que está influenciada por una variedad de factores, incluido el aumento de la temperatura de la superficie del mar. Los resultados de este estudio muestran que el cultivo de cangrejo de fango a pequeña escala tiene menos riesgos y una mayor flexibilidad que el cultivo de cangrejo de fango a gran escala. Podría ser una empresa económicamente sostenible y servir como una herramienta para el alivio de la pobreza en los países en desarrollo si se dispone de apoyo y capacitación en microfinanzas. Aquaculture plays a significant role in food security and provides livelihoods and employment for millions of people among coastal communities worldwide. However, the growing aquaculture sector has also created debates around its long-term ecological sustainability, economic viability, potential social inequalities and governance issues. We investigated the perceived challenges and opportunities to achieving sustainable mud crab aquaculture in tropical coastal regions by using the case study of coastal mud crab farms in Andhra Pradesh, India. Informed by perceptions and indicative financial data from a sample of stakeholders we investigated the potential economic outcomes under different scenarios representing varying yield levels, risk factors and project time periods. The main risks identified by the stakeholders were associated with the limited supply of mud crab seeds and the lack of access to governmental and non-governmental support schemes. There are no financial buffers, therefore major disease outbreaks or extreme weather conditions caused by climate change would lead to a loss of livelihoods. This paper also highlights the most critical factor determining the level of success of mud crab farming being the crab survival rate which is influenced by a variety of factors including increasing sea surface temperature. The results of this study show that small-scale mud crab farming has fewer risks and higher flexibility involved than large-scale mud crab farming. It could be an economically sustainable enterprise and serve as a tool for poverty alleviation in developing countries if microfinance support and training are available. تلعب تربية الأحياء المائية دورًا مهمًا في الأمن الغذائي وتوفر سبل العيش وفرص العمل لملايين الأشخاص بين المجتمعات الساحلية في جميع أنحاء العالم. ومع ذلك، فإن قطاع تربية الأحياء المائية المتنامي قد خلق أيضًا مناقشات حول استدامته البيئية طويلة الأجل، وقابليته الاقتصادية، وعدم المساواة الاجتماعية المحتملة، وقضايا الحوكمة. لقد حققنا في التحديات والفرص المتصورة لتحقيق تربية مستدامة لسرطان البحر الطيني في المناطق الساحلية الاستوائية باستخدام دراسة حالة لمزارع سرطان البحر الطيني الساحلية في ولاية أندرا براديش، الهند. استنادًا إلى التصورات والبيانات المالية الإرشادية من عينة من أصحاب المصلحة، قمنا بالتحقيق في النتائج الاقتصادية المحتملة في ظل سيناريوهات مختلفة تمثل مستويات عائد متفاوتة وعوامل خطر وفترات زمنية للمشروع. ارتبطت المخاطر الرئيسية التي حددها أصحاب المصلحة بمحدودية المعروض من بذور سرطان البحر الطيني وعدم الوصول إلى خطط الدعم الحكومية وغير الحكومية. لا توجد حواجز مالية، وبالتالي فإن تفشي الأمراض الرئيسية أو الظروف الجوية القاسية الناجمة عن تغير المناخ ستؤدي إلى فقدان سبل العيش. تسلط هذه الورقة الضوء أيضًا على العامل الأكثر أهمية الذي يحدد مستوى نجاح زراعة سرطان البحر الطيني وهو معدل بقاء سرطان البحر الذي يتأثر بمجموعة متنوعة من العوامل بما في ذلك زيادة درجة حرارة سطح البحر. تظهر نتائج هذه الدراسة أن زراعة سرطان البحر الطيني على نطاق صغير تنطوي على مخاطر أقل ومرونة أعلى من زراعة سرطان البحر الطيني على نطاق واسع. يمكن أن يكون مشروعًا مستدامًا اقتصاديًا وأن يكون بمثابة أداة للتخفيف من حدة الفقر في البلدان النامية إذا توفر الدعم والتدريب في مجال التمويل الأصغر.

AbstractClimate changes are altering the chemistry of the oceans, and knowing their effects on the biology of animals is urgent. Since the physiological responses of crustaceans may be different given the seasons of the year, this work evaluated the synergistic effect of ocean acidification and seasonality on the physiology of the sea-bob shrimp,Xiphopenaeus kroyeri. Experimental groups were exposed for 5 days to two levels of pH, representing present-day mean ambient conditions (pH 8.0) and distant-future conditions (pH 7.3) during the summer and winter. Metabolism, nitrogen excretion, energy type and storage were determined, respectively, by oxygen consumption, ammonia excretion, atomic ratio O/N and hepatosomatic index. The reduction of pH resulted in a decrease of about 30% in theX. kroyerimetabolism during the summer and winter. Nitrogen excretion (reduction of 40%) and hepatosomatic index (increase of 120%) showed to be altered in animals exposed to reduced pH only throughout summer. Regardless of pH and seasons of the year, animals use mainly proteins as energy substrate and they do not show mortality. The increase of the hepatosomatic index, indicator of the accumulation of energy reserves, associated with metabolism reduction, suggests the suppression of activities that demand energy expenditure. The consequences of the physiological alterations observed may include decreases in growth and reproduction rate and displacement of populations to more appropriate conditions. The results might be associated with a set of factors resulting from the exposure to reduced pH, the synergy between pH and temperature, but also with a pattern of different physiological responses that may occur according to seasonality.

Meteorological forcing at the air-water interface is the main determinant of the heat balance of most lakes (Edinger et al., 1968; Sweers, 1976). Year-to-year changes in the weather therefore have a major effect on the thermal characteristics of lakes. However, lakes that differ with respect to their morphometry respond differently to these changes (Gorham, 1964), with deeper lakes integrating the effects of meteorological forcing over longer periods of time. Other important factors that can influence the thermal characteristics of lakes include hydraulic residence time, optical properties and landscape setting (e.g. Salonen et al., 1984; Fee et al., 1996; Livingstone et al., 1999). These factors modify the thermal responses of the lake to meteorological forcing (cf. Magnuson et al., 2004; Blenckner, 2005) and regulate the patterns of spatial coherence (Chapter 17) observed in the different regions (Livingstone, 1993; George et al., 2000; Livingstone and Dokulil, 2001; Jarvinen et al., 2002; Blenckner et al., 2004)

The SmartBay NIAP fund was made available in 2012 through Dublin City University over a two year period to enable researchers to access the SmartBay Ireland National Test and Demonstration Facility in Galway Bay. Research proposals were invited for funding under a number of activity types that are in line with the objectives of the SmartBay PRTLI Cycle 5 programme. This fund provided small awards (typically €2-25K) to research teams through a national competitive process, which was open to all higher education institutions on the island of Ireland. There were both open and biannual calls. The SmartBay NIAP fund was established to enable researchers in academia and industry to access the SmartBay Ireland national test and demonstration infrastructure. Proposals to access the infrastructure were brief and required information on the researcher(s), a description of the proposed research and its potential impact to the research team arising from the access to SmartBay Ireland. Marine Institute

Sediment cores from three lakes (Moss, Sombre and Heywood) in the maritime Antarctic (Signy Island, South Orkney Islands) have been successfully dated radiometrically by210Pb and137Cs. The core inventories of both fallout radionuclides are an order of magnitude higher than that which can be supported by the direct atmospheric flux at this latitude. The elevated values may be explained by fallout onto the catchment during the winter being delivered directly to the lakes during the annual thaw. Two of the lakes (Sombre and Heywood) show marked increases in sediment accumulation afterc. 1950. This appears to be associated with a documented rise in temperature in the South Orkney Islands, which has caused extensive deglaciation at Signy Island.

The Late Permian mass extinction was not only the most catastrophic known loss of biodiversity, but was followed by unusually prolonged recovery through the Early Triassic. Opinion has been divided on whether delayed recovery was a legacy of especially profound ecological disruption, or due to additional environmental perturbations. New records from the Sydney Basin in southeastern Australia now reveal five successive Late Permian and Early Triassic spikes of unusually high atmospheric CO2 and profound chemical weathering. These successive atmospheric CO2 greenhouse crises coincided with unusually warm and wet paleoclimates for a paleolatitude of 61°S. Successive transient greenhouse crises punctuated long-term, cool, dry, and low-CO2 conditions, and may account for the persistence of low diversity and small size in Early Triassic plants and animals.

Research to date has suggested that both individual marine species and ecological processes are expected to exhibit diverse responses to the environmental effects of climate change. Evolutionary responses can occur on rapid (ecological) timescales, and yet studies typically do not consider the role that adaptive evolution will play in modulating biological responses to climate change. Investigations into such responses have typically been focused at particular biological levels (e.g., cellular, population, community), often lacking interactions among levels. Since all levels of biological organisation are sensitive to global climate change, there is a need to elucidate how different processes and hierarchical interactions will influence species fitness. Therefore, predicting the responses of communities and populations to global change will require multidisciplinary efforts across multiple levels of hierarchy, from the genetic and cellular to communities and ecosystems. Eventually, this may allow us to establish the role that acclimatisation and adaptation will play in determining marine community structures in future scenarios.