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The high mountain forests on Earth are characterized by sharp environmental heterogeneity, high species endemism, and unique phenotypic adaptations. Yet, global warming is jeopardizing this ecosystem as no other as some forests may have nowhere to go beyond the mountain's summits. One of the most human-endangered high-elevation ecosystems is the Polylepis forest. Despite its vulnerability, forecasting climate reactions in this distinctive high mountain forest type remains a formidable challenge. Therefore, in this study, we modeled climate change responses of high-elevation allopatric Polylepis sericea and P. quadrijuga (Rosaceae) in the northern Andes. The analysis took into account VIF-prioritized bioclimatic variables for near-to-present and future (2081–2100 MPI-ESM1-2-HR) conditions. Model selection was carried out following the AUC scores of 12 MaxEnt and six machine learning algorithms. Predictive power reached 0.97 for MaxEnt's model fc.H_rm.1 (H-1). Results indicate a moderate vulnerability of P. sericea, with a 29% loss of area in the trailing edge, due to climate change for the period 2081–2100. On the other hand, P. quadrijuga is likely to experience even larger distribution losses, up to 99%, for the same period. The findings of this study suggest that P. quadrijuga, as compared to P. sericea, exhibits a restricted ability to maintain the corresponding habitat requirements in the face of climatic change. Higher niche specialization of P. quadrijuga in the environmentally heterogeneous Eastern Cordillera contrasts with the more generalist nature of P. sericea in the topographically less complex Central Cordillera. In addition to climate change, this trend may be exacerbated by the detrimental effects of agriculture, mining, and an expanding rural population, which represent significant human-driven pressures yet to be modeled in the northern Andean highlands. Yet, based on previous studies, the historical population dynamics during the past glacial cycles suggests that range shifts could play a more significant role at deeper time scales than previously forecasted in the species' reaction to climate change. Additionally, Polylepis forests may be able to endure at the current locations via local adaptation and plasticity, major drivers of the phenotypic variation in long-lived trees, counteracting the vulnerability scenario under a niche conservatism hypothesis. Ultimately, the modeling procedure employed in this study provides insights into the potential effects of climate change on Polylepis forests 70 years from now. Oncoming studies may consider alternative responses inherent to the gene pool of the species and the interaction with edaphic and biotic agents. We advocate for the application of comparable estimations in other high-elevation tree communities found at the tree line. [ABSTRACT FROM AUTHOR]

Local survival of forest tree populations under climate change depends on existing genetic variation and their adaptability to changing environments. Responses to selection were studied in European beech (Fagus sylvatica) under field conditions. A total of 1087 adult trees, seeds, 1‐year‐old seedlings and established multiyear saplings were genotyped with 16 nuSSRs. Adult trees were assessed for phenotypic traits related to growth, phenology and reproduction. Parentage and paternity analyses were used to estimate effective female and male fecundity as a proxy of fitness and showed that few parents contributed to successful regeneration. Selection gradients were estimated from the relationship between traits and fecundity, while heritability and evolvability were estimated using mixed models and the breeder's equation. Larger trees bearing more fruit and early male flowering had higher total fecundity, while trees with longer growth season had lower total fecundity (directional selection). Stabilizing selection on spring phenology was found for female fecundity, highlighting the role of late frosts as a selection driver. Selection gradients for other traits varied between measurement years and the offspring cohort used to estimate parental fecundity. Compared to other studies in natural populations, we found low to moderate heritability and evolvability for most traits. Response to selection was higher for growth than for budburst, leaf senescence or reproduction traits, reflecting more consistent selection gradients across years and sex functions, and higher phenotypic variability in the population. Our study provides empirical evidence suggesting that populations of long‐lived organisms such as forest trees can adapt locally, even at short‐time scales. [ABSTRACT FROM AUTHOR]

Island communities are the targets for a wide range of interventions designed to help them adapt to climate change. A growing body of research explores the equity and justice implications of adaptation policies and programmes, revealing they often exacerbate, rather than alleviate, inequality within at-risk communities. This paper pushes beyond existing understandings of climate justice, which prioritise its distributive and procedural aspects. Through household surveys, interviews and participant observation, the paper presents a case study of a major adaptation project in a small island community in the Philippines, paying particular attention to its equity implications at the local level. It describes how local politics and power relations distorted the well-intentioned aims of the project and resulted in the project exacerbating, rather than alleviating, pre-existing inequality. Climate change adaptation is a deeply political process that is easily subverted by the interests of the powerful. To mitigate the influence of power and politics in future climate adaptation projects, we present an expanded multidimensional framework for assessing adaptative justice that incorporates the neglected aspects of recognition and structure. [ABSTRACT FROM AUTHOR]

This research enhances our understanding of the complex relationship between climate change, social inequality, and adaption, in urban areas. It is novel, being the first research in this area to be based on a conceptual econometric framework within which multiple stages are explicitly developed, and for which empirical evidence is gathered. We use this approach to examine the role of material, social status, and power inequality in influencing spontaneous adaptation choices in urban settings of China's Yangtze River delta. This framework differentiates two vital stages in adaptation decision making at the household level which allows us to examine, first, how social inequality shapes the severity of climate impact and, second, how social inequality interacts with this experience to influence responses to these impacts. We pilot this approach in selected metropolitan areas of Shanghai and Nanjing. Our results show that all dimensions of social inequality are significantly associated with experiences of climate change and adaptation choice. Application of our conceptual framework provides policymakers and planners with a new and useful tool that can be used to formulate better policy measures that either enable the disadvantaged to adapt in situ or provide these groups with real opportunities and capacities to migrate. [ABSTRACT FROM AUTHOR]

The narratives of migration as adaptation and in situ adaptation are well established in mainstream adaptation policy and are usually presented as independent and opposing trends of action. A common and fundamental element of such narratives is the depoliticized conception of both migration and adaptation. Using a trans-scalar approach, we address the migration–coffee–climate change nexus: first at a regional scale, at the conflictive border of Guatemala–Mexico, to show the contradiction between the current Central American migratory crisis and the narrative of migration as adaptation; second, at a local scale and from an ethnographic perspective, we focus on the process of in situ adaptation in shade-grown coffee plots of smallholder coffee farmers in the Tacaná Volcano cross-border region, between Chiapas and Guatemala. We argue that the dichotomy "in situ adaptation" versus "migration as adaptation" is not useful to capture the intertwined and political nature of both narratives, as illustrated in the case of the renovation of smallholders' coffee plots in a context of climatic changes. We provide elements to contribute towards the repolitization of adaptation from an integral perspective. [ABSTRACT FROM AUTHOR]