• Energy Research
• 15. Life on land close
• 11. Sustainability close
• BE close
• Nottingham Trent University close

As Earth’s climate has varied strongly through geological time, studying the impacts of past climate change on biodiversity helps to understand the risks from future climate change. However, it remains unclear how paleoclimate shapes spatial variation in biodiversity. Here, we assessed the influence of Quaternary climate change on spatial dissimilarity in taxonomic, phylogenetic, and functional composition among neighboring 200-kilometer cells (beta-diversity) for angiosperm trees worldwide. We found that larger glacial-interglacial temperature change was strongly associated with lower spatial turnover (species replacements) and higher nestedness (richness changes) components of beta-diversity across all three biodiversity facets. Moreover, phylogenetic and functional turnover was lower and nestedness higher than random expectations based on taxonomic beta-diversity in regions that experienced large temperature change, reflecting phylogenetically and functionally selective processes in species replacement, extinction, and colonization during glacial-interglacial oscillations. Our results suggest that future human-driven climate change could cause local homogenization and reduction in taxonomic, phylogenetic, and functional diversity of angiosperm trees worldwide.

AbstractGlobal impact models represent process-level understanding of how natural and human systems may be affected by climate change. Their projections are used in integrated assessments of climate change. Here we test, for the first time, systematically across many important systems, how well such impact models capture the impacts of extreme climate conditions. Using the 2003 European heat wave and drought as a historical analogue for comparable events in the future, we find that a majority of models underestimate the extremeness of impacts in important sectors such as agriculture, terrestrial ecosystems, and heat-related human mortality, while impacts on water resources and hydropower are overestimated in some river basins; and the spread across models is often large. This has important implications for economic assessments of climate change impacts that rely on these models. It also means that societal risks from future extreme events may be greater than previously thought.

Abstract The role of root phenes in nitrogen (N) acquisition and biomass production was evaluated in 10 contrasting natural accessions of Arabidopsis thaliana L. Seedlings were grown on vertical agar plates with two different nitrate supplies. The low N treatment increased the root to shoot biomass ratio and promoted the proliferation of lateral roots and root hairs. The cost of a larger root system did not impact shoot biomass. Greater biomass production could be achieved through increased root length or through specific root hair characteristics. A greater number of root hairs may provide a low-resistance pathway under elevated N conditions, while root hair length may enhance root zone exploration under low N conditions. The variability of N uptake and the expression levels of genes encoding nitrate transporters were measured. A positive correlation was found between root system size and high-affinity nitrate uptake, emphasizing the benefits of an exploratory root organ in N acquisition. The expression levels of NRT1.2/NPF4.6, NRT2.2, and NRT1.5/NPF7.3 negatively correlated with some root morphological traits. Such basic knowledge in Arabidopsis demonstrates the importance of root phenes to improve N acquisition and paves the way to design eudicot ideotypes.

La tecnología está transformando las sociedades en todo el mundo. Una innovación importante es la aparición de la robótica y los sistemas autónomos (RAS), que tienen el potencial de revolucionar las ciudades tanto para las personas como para la naturaleza. Sin embargo, las oportunidades y desafíos asociados con el RAS para los ecosistemas urbanos aún no se han considerado sistemáticamente. A continuación, presentamos los resultados de un análisis del horizonte en línea en el que participaron 170 expertos de 35 países. Concluimos que es probable que el RAS transforme el uso de la tierra, los sistemas de transporte y las interacciones entre el ser humano y la naturaleza. Las oportunidades priorizadas se centraron principalmente en el despliegue de RAS para el monitoreo y la gestión de la biodiversidad y los ecosistemas. Se priorizaron menos desafíos. Las que se enfatizaron se refieren a los residuos de ras no recuperados y a la calidad e interpretación de los datos recopilados por ras. Aunque los impactos futuros de la RAS para los ecosistemas urbanos son difíciles de predecir, examinar los desarrollos potencialmente importantes desde el principio es esencial si queremos evitar consecuencias perjudiciales pero aprovechar plenamente los beneficios. Los desafíos futuros y las oportunidades potenciales de la robótica y los sistemas autónomos en los ecosistemas urbanos, y cómo pueden afectar la biodiversidad, se exploran y priorizan a través de un análisis del horizonte global de 170 expertos. La technologie transforme les sociétés du monde entier. Une innovation majeure est l'émergence de la robotique et des systèmes autonomes (RAS), qui ont le potentiel de révolutionner les villes pour les personnes et la nature. Néanmoins, les opportunités et les défis associés aux RAS pour les écosystèmes urbains n'ont pas encore été systématiquement pris en compte. Ici, nous rapportons les résultats d'une analyse d'horizon en ligne impliquant 170 participants experts de 35 pays. Nous concluons que les RAS sont susceptibles de transformer l'utilisation des terres, les systèmes de transport et les interactions entre l'homme et la nature. Les opportunités priorisées étaient principalement centrées sur le déploiement de RAS pour le suivi et la gestion de la biodiversité et des écosystèmes. Moins de défis ont été priorisés. Ceux qui ont été soulignés concernent les déchets environnants provenant des ras non récupérés, ainsi que la qualité et l'interprétation des données collectées par les ras. Bien que les impacts futurs des RAS sur les écosystèmes urbains soient difficiles à prévoir, il est essentiel d'examiner rapidement les développements potentiellement importants si nous voulons éviter les conséquences néfastes mais en tirer pleinement parti. Les défis futurs et les opportunités potentielles de la robotique et des systèmes autonomes dans les écosystèmes urbains, et comment ils peuvent avoir un impact sur la biodiversité, sont explorés et hiérarchisés via un horizon global de 170 experts. Technology is transforming societies worldwide. A major innovation is the emergence of robotics and autonomous systems (RAS), which have the potential to revolutionize cities for both people and nature. Nonetheless, the opportunities and challenges associated with RAS for urban ecosystems have yet to be considered systematically. Here, we report the findings of an online horizon scan involving 170 expert participants from 35 countries. We conclude that RAS are likely to transform land use, transport systems and human–nature interactions. The prioritized opportunities were primarily centred on the deployment of RAS for the monitoring and management of biodiversity and ecosystems. Fewer challenges were prioritized. Those that were emphasized concerns surrounding waste from unrecovered RAS, and the quality and interpretation of RAS-collected data. Although the future impacts of RAS for urban ecosystems are difficult to predict, examining potentially important developments early is essential if we are to avoid detrimental consequences but fully realize the benefits. The future challenges and potential opportunities of robotics and autonomous systems in urban ecosystems, and how they may impact biodiversity, are explored and prioritized via a global horizon scan of 170 experts. تعمل التكنولوجيا على تحويل المجتمعات في جميع أنحاء العالم. يتمثل أحد الابتكارات الرئيسية في ظهور الروبوتات والأنظمة المستقلة (RAS)، والتي لديها القدرة على إحداث ثورة في المدن لكل من الناس والطبيعة. ومع ذلك، لم يتم بعد النظر بشكل منهجي في الفرص والتحديات المرتبطة بـ RAS للنظم الإيكولوجية الحضرية. هنا، نبلغ عن نتائج مسح الأفق عبر الإنترنت الذي شارك فيه 170 خبيرًا من 35 دولة. نستنتج أن RAS من المرجح أن يحول استخدام الأراضي وأنظمة النقل والتفاعلات بين الطبيعة البشرية. تركزت الفرص ذات الأولوية في المقام الأول على نشر RAS لرصد وإدارة التنوع البيولوجي والنظم الإيكولوجية. تم إعطاء الأولوية لتحديات أقل. تلك التي تم التأكيد عليها المخاوف المحيطة بالنفايات من RAS غير المستردة، وجودة وتفسير البيانات التي تم جمعها من RAS. على الرغم من صعوبة التنبؤ بالآثار المستقبلية لـ RAS على النظم الإيكولوجية الحضرية، إلا أن دراسة التطورات المهمة المحتملة في وقت مبكر أمر ضروري إذا أردنا تجنب العواقب الضارة ولكن تحقيق الفوائد بالكامل. يتم استكشاف التحديات المستقبلية والفرص المحتملة للروبوتات والأنظمة المستقلة في النظم الإيكولوجية الحضرية، وكيف يمكن أن تؤثر على التنوع البيولوجي، وتحديد أولوياتها من خلال مسح الأفق العالمي الذي يضم 170 خبيرًا.

AbstractUnderstanding the processes that determine above‐ground biomass (AGB) in Amazonian forests is important for predicting the sensitivity of these ecosystems to environmental change and for designing and evaluating dynamic global vegetation models (DGVMs). AGB is determined by inputs from woody productivity [woody net primary productivity (NPP)] and the rate at which carbon is lost through tree mortality. Here, we test whether two direct metrics of tree mortality (the absolute rate of woody biomass loss and the rate of stem mortality) and/or woody NPP, control variation in AGB among 167 plots in intact forest across Amazonia. We then compare these relationships and the observed variation in AGB and woody NPP with the predictions of four DGVMs. The observations show that stem mortality rates, rather than absolute rates of woody biomass loss, are the most important predictor of AGB, which is consistent with the importance of stand size structure for determining spatial variation in AGB. The relationship between stem mortality rates and AGB varies among different regions of Amazonia, indicating that variation in wood density and height/diameter relationships also influences AGB. In contrast to previous findings, we find that woody NPP is not correlated with stem mortality rates and is weakly positively correlated with AGB. Across the four models, basin‐wide average AGB is similar to the mean of the observations. However, the models consistently overestimate woody NPP and poorly represent the spatial patterns of both AGB and woody NPP estimated using plot data. In marked contrast to the observations, DGVMs typically show strong positive relationships between woody NPP and AGB. Resolving these differences will require incorporating forest size structure, mechanistic models of stem mortality and variation in functional composition in DGVMs.