• Energy Research

Macroclimate warming is often assumed to occur within forests despite the potential for tree cover to modify microclimates. Here, using paired measurements, we compared the temperatures under the canopy versus in the open at 98 sites across 5 continents. We show that forests function as a thermal insulator, cooling the understory when ambient temperatures are hot and warming the understory when ambient temperatures are cold. The understory versus open temperature offset is magnified as temperatures become more extreme and is of greater magnitude than the warming of land temperatures over the past century. Tree canopies may thus reduce the severity of warming impacts on forest biodiversity and functioning.

AbstractEcological and evolutionary theories have proposed that species traits should be important in mediating species responses to contemporary climate change; yet, empirical evidence has so far provided mixed evidence for the role of behavioral, life history, or ecological characteristics in facilitating or hindering species range shifts. As such, the utility of trait‐based approaches to predict species redistribution under climate change has been called into question. We develop the perspective, supported by evidence, that trait variation, if used carefully can have high potential utility, but that past analyses have in many cases failed to identify an explanatory value for traits by not fully embracing the complexity of species range shifts. First, we discuss the relevant theory linking species traits to range shift processes at the leading (expansion) and trailing (contraction) edges of species distributions and highlight the need to clarify the mechanistic basis of trait‐based approaches. Second, we provide a brief overview of range shift–trait studies and identify new opportunities for trait integration that consider range‐specific processes and intraspecific variability. Third, we explore the circumstances under which environmental and biotic context dependencies are likely to affect our ability to identify the contribution of species traits to range shift processes. Finally, we propose that revealing the role of traits in shaping species redistribution may likely require accounting for methodological variation arising from the range shift estimation process as well as addressing existing functional, geographical, and phylogenetic biases. We provide a series of considerations for more effectively integrating traits as well as extrinsic and methodological factors into species redistribution research. Together, these analytical approaches promise stronger mechanistic and predictive understanding that can help society mitigate and adapt to the effects of climate change on biodiversity.

Forest microclimates contrast strongly with the climate outside forests. To fully understand and better predict how forests' biodiversity and functions relate to climate and climate change, microclimates need to be integrated into ecological research. Despite the potentially broad impact of microclimates on the response of forest ecosystems to global change, our understanding of how microclimates within and below tree canopies modulate biotic responses to global change at the species, community and ecosystem level is still limited. Here, we review how spatial and temporal variation in forest microclimates result from an interplay of forest features, local water balance, topography and landscape composition. We first stress and exemplify the importance of considering forest microclimates to understand variation in biodiversity and ecosystem functions across forest landscapes. Next, we explain how macroclimate warming (of the free atmosphere) can affect microclimates, and vice versa, via interactions with land-use changes across different biomes. Finally, we perform a priority ranking of future research avenues at the interface of microclimate ecology and global change biology, with a specific focus on three key themes: (1) disentangling the abiotic and biotic drivers and feedbacks of forest microclimates; (2) global and regional mapping and predictions of forest microclimates; and (3) the impacts of microclimate on forest biodiversity and ecosystem functioning in the face of climate change. The availability of microclimatic data will significantly increase in the coming decades, characterizing climate variability at unprecedented spatial and temporal scales relevant to biological processes in forests. This will revolutionize our understanding of the dynamics, drivers and implications of forest microclimates on biodiversity and ecological functions, and the impacts of global changes. In order to support the sustainable use of forests and to secure their biodiversity and ecosystem services for future generations, microclimates cannot be ignored. Peer reviewed

L'exploitation de la faune sauvage représente l'une des plus grandes menaces pour la survie des espèces selon la Plateforme intergouvernementale scientifique et politique sur la biodiversité et les services écosystémiques. Bien que les effets néfastes du commerce illégal soient bien reconnus, le commerce légal est souvent considéré comme durable malgré le manque de preuves ou de données dans la majorité des cas. Nous examinons la durabilité du commerce des espèces sauvages, l'adéquation des outils, des garanties et des cadres pour comprendre et réglementer le commerce, et identifions les lacunes dans les données qui minent notre capacité à vraiment comprendre la durabilité du commerce. Nous fournissons 183 exemples montrant un commerce non durable dans un large éventail de groupes taxonomiques. Dans la plupart des cas, ni le commerce illégal ni le commerce légal ne sont étayés par des preuves rigoureuses de durabilité, le manque de données sur les niveaux d'exportation et de données de suivi des populations empêchant de véritables évaluations des impacts au niveau des espèces ou des populations. Nous proposons une approche plus prudente du commerce et de la surveillance des espèces sauvages qui exige que ceux qui tirent profit du commerce fournissent une preuve de durabilité. Nous identifions ensuite quatre domaines clés qui doivent être renforcés pour atteindre cet objectif : (1) la collecte de données rigoureuses et les analyses des populations ; (2) le lien entre les quotas commerciaux, l'UICN et les accords internationaux ; (3) l'amélioration des bases de données et de la conformité du commerce ; et (4) une meilleure compréhension des interdictions commerciales, des forces du marché et des substitutions d'espèces. L'adoption de ces domaines clés dans les cadres réglementaires, y compris la CITES, est essentielle à la survie continue de nombreuses espèces menacées. Il n'y a pas de gagnants de la collecte et du commerce non durables : sans gestion durable, non seulement les espèces ou les populations disparaîtront, mais les communautés dépendantes de ces espèces perdront leurs moyens de subsistance. La explotación de la vida silvestre representa una de las mayores amenazas para la supervivencia de las especies según la Plataforma Intergubernamental Científico-Normativa sobre Biodiversidad y Servicios de los Ecosistemas. Si bien los impactos perjudiciales del comercio ilegal son bien reconocidos, el comercio legal a menudo se equipara a ser sostenible a pesar de la falta de pruebas o datos en la mayoría de los casos. Revisamos la sostenibilidad del comercio de vida silvestre, la idoneidad de las herramientas, salvaguardas y marcos para comprender y regular el comercio, e identificamos lagunas en los datos que socavan nuestra capacidad para comprender realmente la sostenibilidad del comercio. Proporcionamos 183 ejemplos que muestran el comercio insostenible en una amplia gama de grupos taxonómicos. En la mayoría de los casos, ni el comercio ilegal ni el legal están respaldados por pruebas rigurosas de sostenibilidad, con la falta de datos sobre los niveles de exportación y los datos de monitoreo de la población que impiden evaluaciones verdaderas de las especies o los impactos a nivel de población. Proponemos un enfoque más preventivo para el comercio y monitoreo de vida silvestre que requiere que aquellos que se benefician del comercio proporcionen pruebas de sostenibilidad. A continuación, identificamos cuatro áreas centrales que deben fortalecerse para lograr este objetivo: (1) recopilación y análisis rigurosos de datos de las poblaciones; (2) vinculación de las cuotas comerciales con la UICN y los acuerdos internacionales; (3) mejora de las bases de datos y el cumplimiento del comercio; y (4) mayor comprensión de las prohibiciones comerciales, las fuerzas del mercado y las sustituciones de especies. Promulgar estas áreas centrales en los marcos regulatorios, incluida la CITES, es esencial para la supervivencia continua de muchas especies amenazadas. No hay ganadores de la recolección y el comercio insostenibles: sin una gestión sostenible, no solo las especies o poblaciones se extinguirán, sino que las comunidades que dependen de estas especies perderán sus medios de vida. Exploitation of wildlife represents one of the greatest threats to species survival according to the Intergovernmental Science-Policy Platform on Biodiversity and Ecosystem Services. Whilst detrimental impacts of illegal trade are well recognised, legal trade is often equated to being sustainable despite the lack of evidence or data in the majority of cases. We review the sustainability of wildlife trade, the adequacy of tools, safeguards, and frameworks to understand and regulate trade, and identify gaps in data that undermine our ability to truly understand the sustainability of trade. We provide 183 examples showing unsustainable trade in a broad range of taxonomic groups. In most cases, neither illegal nor legal trade are supported by rigorous evidence of sustainability, with the lack of data on export levels and population monitoring data precluding true assessments of species or population-level impacts. We propose a more precautionary approach to wildlife trade and monitoring that requires those who profit from trade to provide proof of sustainability. We then identify four core areas that must be strengthened to achieve this goal: (1) rigorous data collection and analyses of populations; (2) linking trade quotas to IUCN and international accords; (3) improved databases and compliance of trade; and (4) enhanced understanding of trade bans, market forces, and species substitutions. Enacting these core areas in regulatory frameworks, including CITES, is essential to the continued survival of many threatened species. There are no winners from unsustainable collection and trade: without sustainable management not only will species or populations become extinct, but communities dependent upon these species will lose livelihoods. يمثل استغلال الحياة البرية أحد أكبر التهديدات لبقاء الأنواع وفقًا للمنبر الحكومي الدولي للعلوم والسياسات في مجال التنوع البيولوجي وخدمات النظم الإيكولوجية. في حين أن الآثار الضارة للاتجار غير المشروع معترف بها جيدًا، إلا أن التجارة القانونية غالبًا ما تكون مستدامة على الرغم من عدم وجود أدلة أو بيانات في غالبية الحالات. نستعرض استدامة تجارة الأحياء البرية، وكفاية الأدوات والضمانات والأطر لفهم التجارة وتنظيمها، وتحديد الثغرات في البيانات التي تقوض قدرتنا على فهم استدامة التجارة حقًا. نقدم 183 مثالًا توضح التجارة غير المستدامة في مجموعة واسعة من المجموعات التصنيفية. في معظم الحالات، لا يتم دعم التجارة غير المشروعة أو القانونية بأدلة صارمة على الاستدامة، مع عدم وجود بيانات عن مستويات التصدير وبيانات رصد السكان التي تحول دون إجراء تقييمات حقيقية للأنواع أو التأثيرات على مستوى السكان. نقترح نهجًا أكثر احترازية لتجارة ورصد الحياة البرية يتطلب من أولئك الذين يستفيدون من التجارة تقديم دليل على الاستدامة. ثم نحدد أربعة مجالات أساسية يجب تعزيزها لتحقيق هذا الهدف: (1) جمع البيانات الدقيقة وتحليل السكان ؛ (2) ربط الحصص التجارية بالاتحاد الدولي لحفظ الطبيعة والموارد الطبيعية والاتفاقات الدولية ؛ (3) تحسين قواعد البيانات والامتثال للتجارة ؛ و (4) تعزيز فهم الحظر التجاري وقوى السوق وبدائل الأنواع. إن سن هذه المجالات الأساسية في الأطر التنظيمية، بما في ذلك اتفاقية الاتجار الدولي بأنواع الحيوانات والنباتات البرية المعرضة للانقراض، أمر ضروري لاستمرار بقاء العديد من الأنواع المهددة بالانقراض. لا يوجد فائزون من الجمع والتجارة غير المستدامين: فبدون الإدارة المستدامة لن تنقرض الأنواع أو المجموعات فحسب، بل ستفقد المجتمعات التي تعتمد على هذه الأنواع سبل عيشها.

AbstractIssueClimate change, and its impacts on ecological, agricultural and other societal systems, is most often studied by relying on temperature data derived from countrywide weather‐station networks. Yet, these data do not capture microclimates, those arising from soil, vegetation and topography, at spatial scales relevant to the majority of organisms on Earth. We argue that a unified strategy is missing to design regional or countrywide networks to measure microclimates and thus provide ecologically relevant and sound climate data, for instance for modelling biodiversity and ecosystem functions.EvidenceHere, we develop an integrative framework to design effective microclimate networks for potential implementation at the country level. With the dawn of novel low‐cost sensor technologies and modelling techniques it is time for designing standardized microclimate networks. We make an important step forward in that regard by providing hands‐on training to generate an optimal sensor distribution to capture as much microclimate diversity as possible at the regional or country scale.ConclusionsBy implementing our framework to design countrywide or regional microclimate networks, strategically positioned to capture a representative picture of microclimates available within the focal country or region, governments could lay the foundation for the development of a next generation of modelling and synthesis of landscapes, to serve a range of societal needs now and into the future as climate change accelerates.

AbstractAimSpecies that respond favourably to environmental change tend to be mobile or dispersive. Living within trees has some benefits over life on the ground. Species that move vertically within forest canopies can take advantage of increased complexity and resource availability, which should correspond to increased resilience to environmental variability and change. Here we show that two modes of movement, arboreality and horizontal dispersal, across an entire bioregional vertebrate fauna in the rain forests of Australia are associated with measures of historical environmental stability.LocationWet Tropics, Queensland, Australia.Time periodHistorical (c. 20,000 years ago) and current (1990‐2009).Major taxa studiedMammal, bird, reptile, and frog species.MethodsWe analysed vertebrate distribution for 195 species and trait data from 20 years of standardized sampling. We derived an arboreality index (i.e., the extent of vertical habitat used by each species) from a large database of field observations combined with expert opinion scores on arboreality. We compared community‐wide trends in arboreality and their horizontal dispersal potential with historical climate since the Last Glacial Maximum (c. 20,000 years ago) and current climate over 20 years of the recent past (1990–2009).ResultsVertical (arboreality) and horizontal (dispersal) movement were positively correlated, and both were negatively correlated with environmental stability. We found that arboreal species dominate communities in historically unstable areas, and these areas have both low richness and low endemism. Further, we show that low‐ and high‐altitude arboreal species experience similar thermal regimes, whereas low‐ and high‐altitude ground‐dwelling species experience little overlap in thermal regimes.Main conclusionHigher variability and overlap in temperature among rain forest canopies suggests less geographical separation in tolerable conditions for arboreal taxa when compared with ground‐dwelling taxa. Increased ecological plasticity in horizontal and vertical movement as well as exposure and pre‐selection to high temperature variability appears to allow arboreal species to exploit climatically uncertain areas, a capacity that may serve them well in responding to future climate change.

AbstractEpiphytes are important for canopy dwelling organisms because they provide a cool and moist microhabitat in the relatively hot and dry canopy. Here we examine whether epiphytic Asplenium ferns act as important habitats for arboreal frogs. We conducted extensive fern and habitat surveys for frogs in the Philippines, and complimented these surveys with roaming day and night canopy surveys to identify the full extent of habitat use across the vertical strata. We artificially dried ferns of various sizes to identify relationships between water and temperature buffering. Ferns are the preferred diurnal microhabitat and breeding habitat for arboreal frogs. A strong positive relationship exists between fern size and frog usage and abundance. Our drying experiments show that large ferns buffer maximum temperatures and reduce variability in temperatures, and buffering is directly linked to their hydration. Frogs are likely using large ferns for their moist, cool, environments for breeding and daytime retreat, which supports the buffered microhabitat hypothesis—these plants promote species coexistence through habitat creation and amelioration of physical stress. However, drying experiments suggest that this buffering is contingent on regular rainfall. Altered rainfall regimes could lead to the unexpected loss of the functional capacity of these important fern habitats.