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Aim: Animal migration strategies balance trade-offs between mortality and reproduction in seasonal environments. Knowledge of broad-scale biogeographical patterns of animal migration is important for understanding ecological drivers of migratory behaviours. Here we present a flyway-scale assessment of the spatial structure and seasonal dynamics of the Afro-Palearctic bird migration system and explore how phenology of the environment guides long-distance migration. Location: Europe and Africa. Time period: 2009–2017. Major taxa studied: Birds. Methods: We compiled an individual-based dataset comprising 23 passerine and near-passerine species of 55 European breeding populations where a total of 564 individuals were tracked migrating between Europe and sub-Saharan Africa. In addition, we used remote sensed observations on primary productivity (NDVI) to estimate the timing of vegetation green-up in spring and senescence in autumn across Europe. First, we described how individual breeding and non-breeding sites and the migratory flyways link geographically. Second, we examined how migration timing along the two major Afro-Palearctic flyways is tuned with vegetation phenology en route and at the breeding sites. Results: While we found the longitudes of individual breeding and non-breeding sites to be strongly positively related, the latitudes of breeding and non-breeding sites were negatively related. In autumn, timing of migration was similar along the Western and the Eastern flyways and happened ahead of the autumnal senescence of vegetation. In spring, migration timing was approximately two weeks later along the Eastern flyway than on the Western flyway which coincided with the later spring green-up in Eastern Europe. Main Conclusions: Migration of the Afro-Palearctic landbirds follows a longitudinally parallel leap-frog migration pattern where migrants track vegetation green-up in spring and depart before vegetation senescence in autumn. However, the ongoing global change have the potential to disrupt this spatiotemporal synchronization between migration timing and spring green-up with variable effects on different migrant populations.

La gestion des risques a réduit la vulnérabilité aux inondations et aux sécheresses dans le monde1,2, mais leurs impacts continuent d'augmenter3. Une meilleure compréhension des causes de l'évolution des impacts est donc nécessaire, mais a été entravée par un manque de données empiriques4,5. Sur la base d'un ensemble de données mondiales de 45 paires d'événements qui se sont produits dans la même zone, nous montrons que la gestion des risques réduit généralement les impacts des inondations et des sécheresses, mais fait face à des difficultés pour réduire les impacts d'événements sans précédent d'une ampleur jamais connue auparavant. Si le deuxième événement était beaucoup plus dangereux que le premier, son impact était presque toujours plus élevé. En effet, la gestion n'a pas été conçue pour faire face à de tels événements extrêmes : par exemple, ils ont dépassé les niveaux de conception des digues et des réservoirs. Dans deux cas de réussite, l'impact du deuxième événement, plus dangereux, a été plus faible, en raison de l'amélioration de la gouvernance de la gestion des risques et des investissements élevés dans la gestion intégrée. La difficulté observée à gérer des événements sans précédent est alarmante, étant donné que des événements hydrologiques plus extrêmes sont projetés en raison du changement climatique3. La gestión de riesgos ha reducido la vulnerabilidad a las inundaciones y sequías a nivel mundial1,2, pero sus impactos siguen aumentando3. Por lo tanto, se necesita una mejor comprensión de las causas de los impactos cambiantes, pero se ha visto obstaculizada por la falta de datos empíricos4,5. Sobre la base de un conjunto de datos global de 45 pares de eventos que ocurrieron dentro de la misma área, mostramos que la gestión de riesgos generalmente reduce los impactos de inundaciones y sequías, pero enfrenta dificultades para reducir los impactos de eventos sin precedentes de una magnitud no experimentada anteriormente. Si el segundo evento era mucho más peligroso que el primero, su impacto era casi siempre mayor. Esto se debe a que la gestión no fue diseñada para hacer frente a tales eventos extremos: por ejemplo, superaron los niveles de diseño de diques y embalses. En dos casos de éxito, el impacto del segundo evento, más peligroso, fue menor, como resultado de una mejor gobernanza de la gestión de riesgos y una alta inversión en la gestión integrada. La dificultad observada para gestionar eventos sin precedentes es alarmante, dado que se proyectan eventos hidrológicos más extremos debido al cambio climático3. Risk management has reduced vulnerability to floods and droughts globally1,2, yet their impacts are still increasing3. An improved understanding of the causes of changing impacts is therefore needed, but has been hampered by a lack of empirical data4,5. On the basis of a global dataset of 45 pairs of events that occurred within the same area, we show that risk management generally reduces the impacts of floods and droughts but faces difficulties in reducing the impacts of unprecedented events of a magnitude not previously experienced. If the second event was much more hazardous than the first, its impact was almost always higher. This is because management was not designed to deal with such extreme events: for example, they exceeded the design levels of levees and reservoirs. In two success stories, the impact of the second, more hazardous, event was lower, as a result of improved risk management governance and high investment in integrated management. The observed difficulty of managing unprecedented events is alarming, given that more extreme hydrological events are projected owing to climate change3. أدت إدارة المخاطر إلى تقليل التعرض للفيضانات والجفاف على مستوى العالم1,2، ومع ذلك لا تزال آثارها تتزايد3. لذلك هناك حاجة إلى فهم أفضل لأسباب تغير التأثيرات، ولكن أعيق ذلك بسبب نقص البيانات التجريبية4، 5. على أساس مجموعة بيانات عالمية مكونة من 45 زوجًا من الأحداث التي وقعت داخل نفس المنطقة، نظهر أن إدارة المخاطر تقلل عمومًا من آثار الفيضانات والجفاف ولكنها تواجه صعوبات في الحد من آثار الأحداث غير المسبوقة ذات الحجم الذي لم تشهده من قبل. إذا كان الحدث الثاني أكثر خطورة من الأول، فإن تأثيره كان دائمًا أعلى. وذلك لأن الإدارة لم تكن مصممة للتعامل مع مثل هذه الأحداث المتطرفة: على سبيل المثال، تجاوزت مستويات تصميم السدود والخزانات. في قصتي نجاح، كان تأثير الحدث الثاني، الأكثر خطورة، أقل، نتيجة لتحسين حوكمة إدارة المخاطر والاستثمار العالي في الإدارة المتكاملة. إن الصعوبة الملحوظة في إدارة الأحداث غير المسبوقة تنذر بالخطر، بالنظر إلى أنه من المتوقع حدوث المزيد من الأحداث الهيدرولوجية المتطرفة بسبب تغير المناخ3.

Herein we highlight a methodological error we encountered in a literature paper concerning the application of graph theory to marine connectivity studies. We show the consequences of this error and propose the use of a metric for the node-to-node distance that solves the inconsistency at the base of it. Our argumentation is illustrated by the analysis of a literature data set. The toolbox contains: 1) Connectivity matrices used for the study 2) Scripts to reproduce the figures in the paper

Fish stomach content records extracted from the DAPSTOM 4.5 database (held at the UK Centre for Environment, Fisheries and Aquaculture Science - CEFAS). Data collated as part of the EU Euro-Basin project and specifically concerning herring (Clupea harengus), mackerel (Scomber scombrus), blue whiting (Micromesistius poutassou), albacore (Thunnus alalunga) and bluefin tuna (Thunnus thynnus). The data set consist of 20720 records - collected throughout the northeast Atlantic, between 1906 and 2011 - mostly during routine fisheries monitoring research cruises.

We evaluated the effects of low pH on Corallium rubrum from aquaria experiments. Several colonies of C. rubrum were long-term maintained for 314 days in aquaria at two different pH levels (8.10 and 7.81, pHT). Calcification rate, spicule morphology, major biochemical constituents (protein, carbohydrates and lipids) and fatty acids composition were measured periodically. Exposure to lower pH conditions caused a significant decrease in the skeletal growth rate in comparison to the control treatment. Similarly, the spicule morphology clearly differed between both treatments at the end of the experiment, with aberrant shapes being observed only under the acidified conditions. On the other hand, while total organic matter was significantly higher under low pH conditions, no significant differences were detected between treatments regarding total carbohydrate, lipid, protein and fatty acid composition. However, the lower variability found among samples maintained in acidified conditions relative to controls, suggests a possible effect of pH decrease on the metabolism of the colonies. Our results show, for the first time, evidence of detrimental ocean acidification effects on this valuable and endangered coral species.

Coccolithophores are an important component of the Earth system, and, as calcifiers, their possible susceptibility to ocean acidification is of major concern. Laboratory studies at enhanced pCO2 levels have produced divergent results without overall consensus. However, it has been predicted from these studies that, although calcification may not be depressed in all species, acidification will produce "a transition in dominance from more to less heavily calcified coccolithophores" [Ridgwell A, et al., (2009) Biogeosciences 6:2611-2623]. A recent observational study [Beaufort L, et al., (2011) Nature 476:80-83] also suggested that coccolithophores are less calcified in more acidic conditions. We present the results of a large observational study of coccolithophore morphology in the Bay of Biscay. Samples were collected once a month for over a year, along a 1,000-km-long transect. Our data clearly show that there is a pronounced seasonality in the morphotypes of Emiliania huxleyi, the most abundant coccolithophore species. Whereas pH and CaCO3 saturation are lowest in winter, the E. huxleyi population shifts from 90% (winter) of the heavily calcified form. However, it is unlikely that the shifts in carbonate chemistry alone caused the morphotype shift. Our finding that the most heavily calcified morphotype dominates when conditions are most acidic is contrary to the earlier predictions and raises further questions about the fate of coccolithophores in a high-CO2 world.

Cold-water corals are amongst the most three-dimensionally complex deep-sea habitats known and are associated with high local biodiversity. Despite their importance as ecosystem engineers, little is known about how these organisms will respond to projected ocean acidification. Since preindustrial times, average ocean pH has already decreased from 8.2 to ~ 8.1. Predicted CO2 emissions will decrease this by up to another 0.3 pH units by the end of the century. This decrease in pH may have a wide range of impacts upon marine life, and in particular upon calcifiers such as cold-water corals. Lophelia pertusa is the most widespread cold-water coral (CWC) species, frequently found in the North Atlantic. Data here relate to a short term data set (21 days) on metabolism and net calcification rates of freshly collected L. pertusa from Mingulay Reef Complex, Scotland. These data from freshly collected L. pertusa from the Mingulay Reef Complex will help define the impact of ocean acidification upon the growth, physiology and structural integrity of this key reef framework forming species.

The tuna stomach database from AZTI-Tecnalia corresponds to 7 years of sampling from 2004 to 2011. Due to the absence of continuity in the different projects dealing with the feeding ecology of tunas, the sampling could not be performed every year for both species, and no sample was collected in 2008. However, the fish stomach content record contents composition - by prey weight - of 1525 albacore caught in the Bay of Biscay and surrounding waters of the North Atlantic Drift Region in 2005 (n=397), 2006 (n=196), 2007 (n=37), 2009 (n=95), 2010 (n=566) and 2011 (n=234) ; and of 686 bluefin tunas caught in the Southeastern Bay of Biscay in 2004 (n=32), 2005 (n=36), 2006 (n=3), 2009 (n=257), 2010 (n=233) and 2011 (n=125). Samples have been obtained from scientific research surveys (using a variety of different fishing gears), from commercial fisheries catches, from individual fish voluntarily sampled by recreational fishermen and from fish accidentally stranded on coastlines. Each predator is identified by an ID and its length and wet weight are given. In case the wet weight could not be measured, it was estimated through a length-weight relationship equation and is indicated in the comment for the Predator mass column. The total weight of each prey is given, as well as the weight of each prey taxonomic group in each stomach.

Arctic phytoplankton and their response to future conditions shape one of the most rapidly changing ecosystems on the planet. We tested how much the phenotypic responses of strains from the same Arctic diatom population diverge and whether the physiology and intraspecific composition of multistrain populations differs from expectations based on single strain traits. To this end, we conducted incubation experiments with the diatom Thalassiosira hyalina under present‐day and future temperature and pCO2 treatments. Six fresh isolates from the same Svalbard population were incubated as mono‐ and multistrain cultures. For the first time, we were able to closely follow intraspecific selection within an artificial population using microsatellites and allele‐specific quantitative PCR. Our results showed not only that there is substantial variation in how strains of the same species cope with the tested environments but also that changes in genotype composition, production rates, and cellular quotas in the multistrain cultures are not predictable from monoculture performance. Nevertheless, the physiological responses as well as strain composition of the artificial populations were highly reproducible within each environment. Interestingly, we only detected significant strain sorting in those populations exposed to the future treatment. This study illustrates that the genetic composition of populations can change on very short timescales through selection from the intraspecific standing stock, indicating the potential for rapid population level adaptation to climate change. We further show that individuals adjust their phenotype not only in response to their physicochemical but also to their biological surroundings. Such intraspecific interactions need to be understood in order to realistically predict ecosystem responses to global change. In order to allow full comparability with other ocean acidification data sets, the R package seacarb (Gattuso et al, 2019) was used to compute a complete and consistent set of carbonate system variables, as described by Nisumaa et al. (2010). In this dataset the original values were archived in addition with the recalculated parameters (see related PI). The date of carbonate chemistry calculation by seacarb is 2020-03-06.

Résumé. Alors que les impacts négatifs des extrêmes hydrologiques augmentent dans de nombreuses régions du monde, une meilleure compréhension des facteurs de changement des risques et des impacts est essentielle pour une gestion efficace des risques d'inondation et de sécheresse et pour l'adaptation au climat. Cependant, il existe actuellement un manque de données empiriques complètes sur les processus, les interactions et les rétroactions dans les systèmes homme-eau complexes conduisant à des impacts d'inondation et de sécheresse. Nous présentons ici un ensemble de données de référence contenant des données socio-hydrologiques d'événements appariés, c'est-à-dire deux inondations ou deux sécheresses survenues dans la même zone. Les 45 événements appariés se sont produits dans 42 zones d'étude différentes et couvrent un large éventail de conditions socio-économiques et hydro-climatiques. L'ensemble de données est unique en ce qu'il couvre à la fois les inondations et les sécheresses, le nombre de cas évalués et la quantité de données socio-hydrologiques. L'ensemble de données de référence comprend : 1) des rapports de style d'examen détaillés sur les événements et les processus clés entre les deux événements d'une paire ; 2) le tableau de données clés contenant des variables qui évaluent les indicateurs qui caractérisent les lacunes de gestion, le danger, l'exposition, la vulnérabilité et les impacts de tous les événements ; 3) un tableau des indicateurs de changement qui indiquent les différences entre le premier et le deuxième événement d'une paire. Les avantages de l'ensemble de données sont qu'il permet des analyses comparatives entre tous les événements appariés sur la base des indicateurs de changement et permet des évaluations détaillées spécifiques au contexte et à l'emplacement sur la base des données et des rapports détaillés des zones d'étude individuelles. L'ensemble de données peut être utilisé par la communauté scientifique pour des analyses de données exploratoires, par exemple axées sur les liens de causalité entre la gestion des risques, les changements de danger, l'exposition et la vulnérabilité et les impacts des inondations ou de la sécheresse. Les données peuvent également être utilisées pour le développement, l'étalonnage et la validation de modèles socio-hydrologiques. L'ensemble de données est accessible au public via les services de données de GFZ (Kreibich et al. 2023, lien pour examen : https://dataservices.gfz-potsdam.de/panmetaworks/review/923c14519deb04f83815ce108b48dd2581d57b90ce069bec9c948361028b8c85/). Resumen. A medida que aumentan los impactos adversos de los extremos hidrológicos en muchas regiones del mundo, es esencial comprender mejor los impulsores de los cambios en el riesgo y los impactos para una gestión eficaz del riesgo de inundaciones y sequías y la adaptación al clima. Sin embargo, actualmente existe una falta de datos empíricos exhaustivos sobre los procesos, interacciones y retroalimentaciones en sistemas complejos de agua-humanos que conducen a los impactos de inundaciones y sequías. Aquí presentamos un conjunto de datos de referencia que contiene datos sociohidrológicos de eventos emparejados, es decir, dos inundaciones o dos sequías que ocurrieron en la misma área. Los 45 eventos emparejados ocurrieron en 42 áreas de estudio diferentes y cubren una amplia gama de condiciones socioeconómicas e hidroclimáticas. El conjunto de datos es único en cuanto a la cobertura tanto de inundaciones como de sequías, en el número de casos evaluados y en la cantidad de datos sociohidrológicos. El conjunto de datos de referencia comprende: 1) informes detallados de estilo de revisión sobre los eventos y procesos clave entre los dos eventos de un par; 2) la tabla de datos clave que contiene variables que evalúan los indicadores que caracterizan las deficiencias de gestión, el peligro, la exposición, la vulnerabilidad y los impactos de todos los eventos; 3) una tabla de los indicadores de cambio que indican las diferencias entre el primer y el segundo evento de un par. Las ventajas del conjunto de datos son que permite análisis comparativos en todos los eventos emparejados basados en los indicadores de cambio y permite evaluaciones detalladas específicas del contexto y la ubicación basadas en los amplios datos e informes de las áreas de estudio individuales. El conjunto de datos puede ser utilizado por la comunidad científica para análisis de datos exploratorios, por ejemplo, centrados en los vínculos causales entre la gestión de riesgos, los cambios en los peligros, la exposición y la vulnerabilidad y los impactos de inundaciones o sequías. Los datos también se pueden utilizar para el desarrollo, calibración y validación de modelos sociohidrológicos. El conjunto de datos está disponible para el público a través de GFZ Data Services (Kreibich et al. 2023, enlace para revisión: https://dataservices.gfz-potsdam.de/panmetaworks/review/923c14519deb04f83815ce108b48dd2581d57b90ce069bec9c948361028b8c85/). Abstract. As the adverse impacts of hydrological extremes increase in many regions of the world, a better understanding of the drivers of changes in risk and impacts is essential for effective flood and drought risk management and climate adaptation. However, there is currently a lack of comprehensive, empirical data about the processes, interactions and feedbacks in complex human-water systems leading to flood and drought impacts. Here we present a benchmark dataset containing socio-hydrological data of paired events, i.e., two floods or two droughts that occurred in the same area. The 45 paired events occurred in 42 different study areas and cover a wide range of socio-economic and hydro-climatic conditions. The dataset is unique in covering both floods and droughts, in the number of cases assessed, and in the quantity of socio-hydrological data. The benchmark dataset comprises: 1) detailed review style reports about the events and key processes between the two events of a pair; 2) the key data table containing variables that assess the indicators which characterise management shortcomings, hazard, exposure, vulnerability and impacts of all events; 3) a table of the indicators-of-change that indicate the differences between the first and second event of a pair. The advantages of the dataset are that it enables comparative analyses across all the paired events based on the indicators-of-change and allows for detailed context- and location-specific assessments based on the extensive data and reports of the individual study areas. The dataset can be used by the scientific community for exploratory data analyses e.g. focused on causal links between risk management, changes in hazard, exposure and vulnerability and flood or drought impacts. The data can also be used for the development, calibration and validation of socio-hydrological models. The dataset is available to the public through the GFZ Data Services (Kreibich et al. 2023, link for review: https://dataservices.gfz-potsdam.de/panmetaworks/review/923c14519deb04f83815ce108b48dd2581d57b90ce069bec9c948361028b8c85/). الخلاصة: مع زيادة الآثار السلبية للظواهر الهيدرولوجية المتطرفة في العديد من مناطق العالم، يعد الفهم الأفضل لدوافع التغيرات في المخاطر والآثار أمرًا ضروريًا للإدارة الفعالة لمخاطر الفيضانات والجفاف والتكيف مع المناخ. ومع ذلك، هناك حاليًا نقص في البيانات التجريبية الشاملة حول العمليات والتفاعلات والتغذية المرتدة في أنظمة المياه البشرية المعقدة التي تؤدي إلى آثار الفيضانات والجفاف. نقدم هنا مجموعة بيانات مرجعية تحتوي على بيانات اجتماعية هيدرولوجية للأحداث المزدوجة، أي فيضانان أو موجتي جفاف وقعتا في نفس المنطقة. وقعت الأحداث الـ 45 المزدوجة في 42 منطقة دراسة مختلفة وتغطي مجموعة واسعة من الظروف الاجتماعية والاقتصادية والمائية المناخية. مجموعة البيانات فريدة من نوعها في تغطية كل من الفيضانات والجفاف، وفي عدد الحالات التي تم تقييمها، وفي كمية البيانات الاجتماعية الهيدرولوجية. تشتمل مجموعة البيانات المعيارية على: 1) تقارير أسلوب المراجعة التفصيلية حول الأحداث والعمليات الرئيسية بين حدثين للزوج ؛ 2) جدول البيانات الرئيسية الذي يحتوي على المتغيرات التي تقيم المؤشرات التي تميز أوجه القصور في الإدارة والمخاطر والتعرض والضعف وتأثيرات جميع الأحداث ؛ 3) جدول مؤشرات التغيير التي تشير إلى الاختلافات بين الحدث الأول والثاني للزوج. تتمثل مزايا مجموعة البيانات في أنها تمكن من إجراء تحليلات مقارنة عبر جميع الأحداث المقترنة بناءً على مؤشرات التغيير وتسمح بإجراء تقييمات مفصلة للسياق والموقع بناءً على البيانات والتقارير الشاملة لمناطق الدراسة الفردية. يمكن للمجتمع العلمي استخدام مجموعة البيانات لتحليل البيانات الاستكشافية، على سبيل المثال التركيز على الروابط السببية بين إدارة المخاطر والتغيرات في المخاطر والتعرض والضعف وآثار الفيضانات أو الجفاف. يمكن أيضًا استخدام البيانات لتطوير النماذج الاجتماعية الهيدرولوجية ومعايرتها والتحقق من صحتها. مجموعة البيانات متاحة للجمهور من خلال خدمات بيانات GFZ (Kreibich et al. 2023، رابط للمراجعة: https://dataservices.gfz-potsdam.de/panmetaworks/review/923c14519deb04f83815ce108b48dd2581d57b90ce069bec9c948361028b8c85/).