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The Paris Agreement articulates a global goal on adaptation, which aims to ensure an ‘adequate adaptation response’ to the ‘global temperature goal’, and requires countries to report progress through periodic global stocktakes. However, there remain conceptual and methodological challenges in defining an adaptation goal and mixed evidence on what effective adaptation looks like and how it can be enabled. In this review, we demonstrate how different normative views on adaptation outcomes, arising from different epistemological and disciplinary entry points, can lead to very different interpretations of adaptation effectiveness. We argue that how effectiveness is framed will significantly impact adaptation implementation and outcomes. This, furthermore, represents a way of exercising influence in adaptation decision-making. Eleven principles of effective adaptation are distilled as a way to pluralize guidance in international processes such as the Global Stocktake as well as national and sub-national exercises on tracking and monitoring adaptation.

AbstractClimatic and edaphic effects are increasingly being discussed in the context of biodiversity-ecosystem functioning. Here we use data from West African semi-arid tree savannas and contrasting climatic conditions (lowervs. higher mean annual precipitation-MAP and mean annual temperature-MAT) to (1) determine how climate modulates the effects of species richness on aboveground carbon (AGC); (2) explore how species richness and AGC relate with soil variables in these contrasting climatic conditions; and (3) assess how climate and soil influence directly, and/or indirectly AGC through species richness and stand structural attributes such as tree density and size variation. We find that greater species richness is generally associated with higher AGC, but more strongly in areas with higher MAP, which also have greater stem density.There is a climate-related influence of soils on AGC, which decreases from lower to higher MAP conditions. Variance partitioning analyses and structural equation modelling show that, across all sites, MAP, relative to soils, has smaller effect on AGC, mediated by stand structural attributes whereas soil texture and fertility explain 14% of variations in AGC and influence AGC directly and indirectly via species richness and stand structural attributes. Our results highlight coordinated effects of climate and soils on AGC, which operated primarily via the mediation role of species diversity and stand structures.

ABSTRACTMarine animal forests (MAFs) are benthic ecosystems characterised by biogenic three‐dimensional structures formed by suspension feeders such as corals, gorgonians, sponges and bivalves. They comprise highly diversified communities among the most productive in the world's oceans. However, MAFs are in decline due to global and local stressors that threaten the survival and growth of their foundational species and associated biodiversity. Innovative and scalable interventions are needed to address the degradation of MAFs and increase their resilience under global change. Surprisingly, few studies have considered trophic interactions and heterotrophic feeding of MAF suspension feeders as an integral component of MAF conservation. Yet, trophic interactions are important for nutrient cycling, energy flow within the food web, biodiversity, carbon sequestration, and MAF stability. This comprehensive review describes trophic interactions at all levels of ecological organisation in tropical, temperate, and cold‐water MAFs. It examines the strengths and weaknesses of available tools for estimating the heterotrophic capacities of the foundational species in MAFs. It then discusses the threats that climate change poses to heterotrophic processes. Finally, it presents strategies for improving trophic interactions and heterotrophy, which can help to maintain the health and resilience of MAFs.

AbstractBackgroundTop-soil microbiomes make a vital contribution to the Earth’s ecology and harbor an extraordinarily high biodiversity. They are also key players in many ecosystem services, particularly in arid regions of the globe such as the African continent. While several recent studies have documented patterns in global soil microbial ecology, these are largely biased towards widely studied regions and rely on models to interpolate the microbial diversity of other regions where there is low data coverage. This is the case for sub-Saharan Africa, where the number of regional microbial studies is very low in comparison to other continents.ResultsThe aim of this study was to conduct an extensive biogeographical survey of sub-Saharan Africa’s top-soil microbiomes, with a specific focus on investigating the environmental drivers of microbial ecology across the region. In this study, we sampled 810 sample sites across 9 sub-Saharan African countries and used taxonomic barcoding to profile the microbial ecology of these regions. Our results showed that the sub-Saharan nations included in the study harbor qualitatively distinguishable soil microbiomes. In addition, using soil chemistry and climatic data extracted from the same sites, we demonstrated that the top-soil microbiome is shaped by a broad range of environmental factors, most notably pH, precipitation, and temperature. Through the use of structural equation modeling, we also developed a model to predict how soil microbial biodiversity in sub-Saharan Africa might be affected by future climate change scenarios. This model predicted that the soil microbial biodiversity of countries such as Kenya will be negatively affected by increased temperatures and decreased precipitation, while the fungal biodiversity of Benin will benefit from the increase in annual precipitation.ConclusionThis study represents the most extensive biogeographical survey of sub-Saharan top-soil microbiomes to date. Importantly, this study has allowed us to identify countries in sub-Saharan Africa that might be particularly vulnerable to losses in soil microbial ecology and productivity due to climate change. Considering the reliance of many economies in the region on rain-fed agriculture, this study provides crucial information to support conservation efforts in the countries that will be most heavily impacted by climate change.

La quantification à l'échelle du paysage permet aux agriculteurs de mettre en commun leurs ressources et leur expertise. Cependant, le problème demeure de savoir comment quantifier ces gains. Cet article examine les méthodes actuelles de quantification des gaz à effet de serre (GES) qui peuvent être utilisées dans une analyse à l'échelle du paysage en termes de pertinence pour les zones dominées par les petits exploitants dans les pays en développement. Dans les cadres de comptabilisation du carbone à l'échelle du paysage, les mesures sont un élément essentiel. Les stratégies d'échantillonnage doivent être soigneusement conçues pour tenir compte de tous les pools/flux et pour assurer une utilisation judicieuse des ressources. Les modèles peuvent être utilisés pour augmenter les mesures et combler les lacunes en matière de données. Ces dernières années, un certain nombre de modèles et de calculatrices accessibles ont été développés et peuvent être utilisés à l'échelle du paysage dans les zones en développement. Certains sont basés sur la méthode du Groupe d'experts intergouvernemental sur l'évolution du climat (GIEC) et d'autres sur des modèles d'écosystèmes dynamiques. Ils ont été développés pour une gamme d'objectifs différents et varient donc en termes de précision et de facilité d'utilisation. Les évaluations à l'échelle du paysage des GES nécessitent une combinaison d'échantillonnage au sol, d'utilisation de données de recensement, de télédétection (RS) ou d'autres sources et de modélisation. L'ajustement de tous ces aspects ensemble doit être effectué avec soin pour minimiser les incertitudes et maximiser l'utilisation de ressources rares. Cela est particulièrement vrai dans les paysages hétérogènes dominés par les petits exploitants des pays en développement. La cuantificación a escala de paisaje permite a los agricultores aunar recursos y experiencia. Sin embargo, el problema sigue siendo cómo cuantificar estas ganancias. Este artículo considera los métodos actuales de cuantificación de gases de efecto invernadero (GEI) que se pueden utilizar en un análisis a escala de paisaje en términos de relevancia para las áreas dominadas por los pequeños agricultores en los países en desarrollo. En los marcos de contabilidad de carbono a escala del paisaje, las mediciones son un elemento esencial. Las estrategias de muestreo necesitan un diseño cuidadoso para tener en cuenta todos los grupos/flujos y garantizar un uso juicioso de los recursos. Los modelos se pueden utilizar para ampliar las mediciones y llenar los vacíos de datos. En los últimos años se han desarrollado una serie de modelos y calculadoras accesibles que se pueden utilizar a escala de paisaje en áreas de países en desarrollo. Algunos se basan en el método del Grupo Intergubernamental de Expertos sobre el Cambio Climático (IPCC) y otros en modelos de ecosistemas dinámicos. Se han desarrollado para una variedad de propósitos diferentes y, por lo tanto, varían en términos de precisión y facilidad de uso. Las evaluaciones a escala del paisaje de los GEI requieren una combinación de muestreo del suelo, uso de datos del censo, teledetección (RS) u otras fuentes y modelado. El ajuste de todos estos aspectos juntos debe realizarse cuidadosamente para minimizar las incertidumbres y maximizar el uso de recursos escasos. Esto es especialmente cierto en paisajes heterogéneos dominados por pequeños agricultores en países en desarrollo. Landscape scale quantification enables farmers to pool resources and expertise. However, the problem remains of how to quantify these gains. This article considers current greenhouse gas (GHG) quantification methods that can be used in a landscape scale analysis in terms of relevance to areas dominated by smallholders in developing countries. In landscape scale carbon accounting frameworks, measurements are an essential element. Sampling strategies need careful design to account for all pools/fluxes and to ensure judicious use of resources. Models can be used to scale-up measurements and fill data gaps. In recent years a number of accessible models and calculators have been developed which can be used at the landscape scale in developing country areas. Some are based on the Intergovernmental Panel on Climate Change (IPCC) method and others on dynamic ecosystem models. They have been developed for a range of different purposes and therefore vary in terms of accuracy and usability. Landscape scale assessments of GHGs require a combination of ground sampling, use of data from census, remote sensing (RS) or other sources and modelling. Fitting of all of these aspects together needs to be performed carefully to minimize uncertainties and maximize the use of scarce resources. This is especially true in heterogeneous landscapes dominated by smallholders in developing countries. يمكّن القياس الكمي على نطاق المناظر الطبيعية المزارعين من تجميع الموارد والخبرات. ومع ذلك، لا تزال المشكلة تكمن في كيفية قياس هذه المكاسب. تتناول هذه المقالة طرق القياس الكمي الحالية لغازات الدفيئة (GHG) التي يمكن استخدامها في تحليل مقياس المناظر الطبيعية من حيث صلتها بالمناطق التي يهيمن عليها أصحاب الحيازات الصغيرة في البلدان النامية. في أطر محاسبة الكربون على نطاق المناظر الطبيعية، تعد القياسات عنصرًا أساسيًا. تحتاج استراتيجيات أخذ العينات إلى تصميم دقيق لمراعاة جميع المسابح/التدفقات ولضمان الاستخدام الحكيم للموارد. يمكن استخدام النماذج لتوسيع نطاق القياسات وسد الفجوات في البيانات. في السنوات الأخيرة، تم تطوير عدد من النماذج والآلات الحاسبة التي يمكن الوصول إليها والتي يمكن استخدامها على نطاق المناظر الطبيعية في مناطق البلدان النامية. يعتمد بعضها على طريقة الهيئة الحكومية الدولية المعنية بتغير المناخ (IPCC) والبعض الآخر على نماذج النظم الإيكولوجية الديناميكية. وقد تم تطويرها لمجموعة من الأغراض المختلفة، وبالتالي تختلف من حيث الدقة وسهولة الاستخدام. تتطلب تقييمات مقياس المناظر الطبيعية لغازات الدفيئة مزيجًا من أخذ العينات الأرضية، واستخدام البيانات من التعداد، والاستشعار عن بعد (RS) أو غيرها من المصادر والنمذجة. يجب إجراء تركيب جميع هذه الجوانب معًا بعناية لتقليل أوجه عدم اليقين وتعظيم استخدام الموارد النادرة. وينطبق هذا بشكل خاص على المناظر الطبيعية غير المتجانسة التي يهيمن عليها أصحاب الحيازات الصغيرة في البلدان النامية.

This paper presents an investigation on the influences of clay brick particles on the performance of cement stabilized recycled aggregate as pavement base. The comparative tests of unconfined compressive strength, compressive modulus of resilience, frost resistance, scouring resistance, drying shrinkage and temperature shrinkage of 6 kinds of mixtures with different coarse and fine clay brick particle contents were carried out. Test results showed that the unconfined compressive strength of cement stabilized recycled aggregate was compromised by the clay brick particles, especially the lateral strength. The coarse clay brick particles had little influence on the compressive resilience modulus of the mixture, while the fine clay brick particles could significantly increase it. The frost resistance of the mixture increased first and then slightly decreased with the increase of the content of coarse clay brick particle, while it increased with the increase of fine particle content. The scoured mass loss increased with the increase of coarse clay brick particle content. However, it is discovered that the fine clay brick particles had almost no influences on the scoured mass loss. The addition of both coarse and fine clay brick particles could decrease the drying shrinkage of the mixture at early construction stage. The temperature shrinkage performance of the mixture was not so sensitive to the addition of clay brick particles. Generally, the cement stabilized recycled aggregate with clay brick particles could meet the requirements of the pavement base in many cases but it needs to be optimized in application with consideration of the load and climate conditions.