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Mutualistic interactions are key to sustaining Earth's biodiversity. Yet, we are only beginning to understand how coevolution in mutualistic assemblages can shape the distribution and persistence of species across landscapes. Here, we combine the geographic mosaic theory of coevolution with metacommunity dynamics to understand how geographically structured selection can shape patterns of richness, dispersal, extinction and persistence of mutualistic species. In this model, species may experience strong or weak reciprocal selection imposed by mutualisms within each patch (i.e. hotspots and coldspots, respectively). Using numerical simulations, we show that mutualistic coevolution leads to a concentration of species richness at hotspots. Such an effect occurs because hotspots sustain higher rates of colonization and lower rates of extinction than coldspots, whether the environment changes or not. Importantly, under environmental changes, coldspots fail to sustain a positive colonization-to-extinction balance. Rather, species persistence within coldspots relies on hotspots acting as biodiversity sources and enhancing population dispersal across the landscape. In fact, even a few hotspots in the landscape can fuel the spatial network of dispersal of populations in the metacommunity. Our study highlights that coevolutionary hotspots can act as biodiversity sources, favouring colonization and allowing species to expand their distribution across landscapes even in changing environments. This article is part of the theme issue 'Diversity-dependence of dispersal: interspecific interactions determine spatial dynamics'.

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INTRODUCTION: The collection of Bertholletia excelsa Bonpl. (castanha-da-Amazônia; Brazil nuts) seeds make up part of the everyday activities of the traditional populations that have inhabited all of the Amazon basin since remote times. Nonetheless, knowledge about these harvesting activities in native forest areas has not been well documented. The present study was designed to better understand the significance of this harvesting activity as well as the traditional ecological knowledge of the harvesters. METHODS: Utilizamos entrevistas semiestruturadas para a coleta de dados com extrativistas de castanha, moradores de Caroebe, Roraima (n = 18) durante o período de março de 2021 a março de 2022. The data analysis was based on the frequency of responses to socio-economic questions and their knowledge about that plant species as well as why those interviewees chose that line of work. We also adopted the Spearman and Mann-Whitney non-parametric tests to correlate variables identified in the study, and selected sections of their depositions to highlight the traditional knowledge of the interviewees and their experiences as harvesters. RESULTS: Constatamos que as razões para a escolha do trabalho com o extrativismo para todos os entrevistados é a necessidade de renda complementar, tradição familiar (55%), the sense of well-being provided by contact with the natural environment (25%), and a favorable disposition toward that type of work (11%). Harvesting involves collective work, and many of the interviewees had engaged in those efforts to help their families since their childhood or adolescence. The older harvesters cited more animal species that consumed the Brazil nuts (ρ = 0.60; p = 0.009) and perceived more and greater changes in the environment that were prejudicial to the Brazil nut trees (U = 9.50; p = 0.022). The interviewees who reported lower incomes cited more significant cultural changes and more suggestions concerning conservation activities. According to their statements, deforestation, and the burning and illegal cutting of native trees, including Brazil nut trees, have contributed to environmental change in the region and raised significant concerns about the future of harvesting activities. CONCLUSION: The activities of the "nut-crackers" represent to them more than just a simple source of income, as harvesting provides them with a connection to nature that promotes their well-being and cultural heritage. The nut harvesters have gained specific knowledge concerning both environmental and cultural changes. Those changes have mainly come about through the expansion of agricultural activities and the felling of native forests-which are the main threats to the future of Brazil nut extraction. Attributing value to the folk knowledge of those harvesters would strengthen the local economy, promote forest conservation, and help to better understand the impacts of anthropic activities on the forest and the harvesting of natural products.

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The tropical Andes are a species-rich and nitrogen-limited system, susceptible to increased nitrogen (N) inputs from the atmosphere. However, our understanding of the impacts of increased N input on belowground systems, in particular on protists and their role in nutrient cycling, remains limited. We explored how increased N affects protists in tropical montane rainforests in Ecuador using high-throughput sequencing (HTS) of environmental DNA from two litter layers. In addition, we manipulated the amount of arbuscular mycorrhizal fungi (AMF) and mesofauna, both playing a significant role in N cycling and interacting in complex ways with protist communities. We found that N strongly affected protist community composition in both layers, while mesofauna reduction had a stronger effect on the lower layer. Changes in concentration of the AMF marker lipid had little effect on protists. In both layers, the addition of N increased phagotrophs and animal parasites and decreased plant parasites, while mixotrophs decreased in the upper layer but increased in the lower layer. In the upper layer with higher AMF concentration, mixotrophs decreased, while in the lower layer, photoautotrophs increased and plant parasites decreased. With reduced mesofauna, phagotrophs increased and animal parasites decreased in both layers, while plant parasites increased only in the upper layer. The findings indicate that to understand the intricate response of protist communities to environmental changes, it is critical to thoroughly analyze these communities across litter and soil layers, and to include HTS.

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Land use and cover change (LUCC) in Brazil encompass a complex interplay of diverse factors across different biomes. Understanding these dynamics is crucial for informed decision-making and sustainable land management. In this study, we comprehensively analyzed LUCC patterns and drivers using 30 m resolution MapBiomas Collection 6.0 data (1985-2020). By mapping deforestation of primary and secondary natural vegetation, natural vegetation regeneration, and transitions between pasture, soybean, agriculture, and irrigation, we shed light on the intricate nature of LUCC in Brazil. Our findings highlight significant and increasing trends of deforestation in primary vegetation in the country. Simultaneously, the Atlantic Forest, Caatinga, Pampa, and other regions of the Cerrado have experienced intensification processes. Notably, the pasture area in Brazil reached its peak in 2006 and has since witnessed a gradual replacement by soybean and other crops. While pasture-driven deforestation persists in most biomes, the net pasture area has only increased in the Amazon and Pantanal, decreasing in other biomes due to the conversion of pasturelands to intensive cropping in other regions. Our analysis further reveals that primary and secondary vegetation deforestation accounts for a substantial portion of overall forest loss, with 72 % and 17 %, respectively. Of the cleared areas, 48 % were in pasture, 9 % in soybean cultivation, and 16 % in other agricultural uses in 2020. Additionally, we observed a lower rate of deforestation in the Atlantic Forest, a biome that has been significantly influenced by anthropogenic activities since 1986. This holistic quantification of LUCC dynamics provides a solid foundation for understanding the impacts of these changes on local to continental-scale land-atmosphere interactions. By unraveling the complex nature of LUCC in Brazil, this study aims to contribute to the development of effective strategies for sustainable land management and decision-making processes.

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Linking local to regional ecological and evolutionary processes is key to understand the response of Earth's biodiversity to environmental changes. Here we integrate evolution and mutualistic coevolution in a model of metacommunity dynamics and use numerical simulations to understand how coevolution can shape species distribution and persistence in landscapes varying in space and time. Our simulations show that coevolution and species richness can synergistically shape distribution patterns by increasing colonization and reducing extinction of populations in metacommunities. Although conflicting selective pressures emerging from mutualisms may increase mismatches with the local environment and the rate of local extinctions, coevolution increases trait matching among mutualists at the landscape scale, counteracting local maladaptation and favouring colonization and range expansions. Our results show that by facilitating colonization, coevolution can also buffer the effects of environmental changes, preventing species extinctions and the collapse of metacommunities. Our findings reveal the mechanisms whereby coevolution can favour persistence under environmental changes and highlight that these positive effects are greater in more diverse systems that retain landscape connectivity.

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RESUMEN Ante la presión antropogénica sobre el medio ambiente, es preponderante el rol de la educación ambiental para generar cambios que resignifiquen la relación ser humano-naturaleza en los territórios. Esta investigación cualitativa hermenêutica tuvo un enfoque descriptivo explicativo y en ella se estudiaron cambios culturales y socioambientales promovidos por procesos específicos de educación ambiental no formal realizados en Santiago de Cali - Colombia acerca de conservación de bienes ambientales y servicios ecosistémicos, embellecimiento del entorno, soberania alimentaria y preservación de la biodiversidad. Se identificaron indicadores de educación ambiental potenciales para valorar los cambios promovidos, se definieron indicadores específicos indagando experiencias, percepciones y motivaciones de actores sociales participantes y se contrastó su correspondencia desde la ecologia política y el pensamiento ambiental crítico. Se encontró que la definición de indicadores de educación ambiental presenta retos considerables y que, si bien los procesos educativos posibilitaron una mejor comprensión de las problemáticas medioambientales, los cambios culturales y socioambientales promovidos dependen de dinâmicas socioeconómicas, prácticas éticas, culturales y del ejercicio del poder político.

ABSTRACT In the face of anthropogenic pressure on the environment, the role of environmental education to generate changes that redefine the human-nature relationship in the territories is preponderant. This qualitative hermeneutic research had a descriptive explanatory approach and studied cultural and socio-environmental changes promoted by specific non-formal environmental education processes carried out in Santiago de Cali - Colombia regarding the conservation of environmental goods and ecosystem services, beautification of the environment, food sovereignty and preservation of biodiversity Potential environmental education indicators were identified to assess the changes promoted, specific indicators were defined by investigating experiences, perceptions and motivations of participating social actors and their correspondence was contrasted from political ecology and critical environmental thinking. It was found that the definition of environmental education indicators presents considerable challenges and that, although the educational processes enabled a better understanding of environmental issues, the cultural and socio-environmental changes promoted depend on socioeconomic dynamics, ethical and cultural practices and the exercise of political power.

RESUMO Diante da pressão antropogênica sobre o meio ambiente, o papel da educação ambiental na geração de mudanças que redefinem a relação homem-natureza nos territórios é preponderante. Esta pesquisa hermenêutica qualitativa teve uma abordagem explicativa descritiva e estudou as mudanças culturais e socioambientais promovidas por processos específicos de educação ambiental não-formal realizados em Santiago de Cali - Colombia sobre a conservação dos bens e serviços ambientais, o embelezamento do meio ambiente, a soberania alimentar e a preservação da biodiversidade. Indicadores potenciais de educação ambiental foram identificados para avaliar as mudanças promovidas, indicadores específicos foram definidos através de pesquisas sobre as experiências, percepções e motivações dos atores sociais participantes e sua correspondência foi contrastada a partir da perspectiva da ecologia politica e do pensamento ambiental crítico. Verificou-se que a definição de indicadores de educação ambiental apresenta desafios consideráveis e que, embora os processos educacionais tenham levado a uma melhor compreensão das questões ambientais, as mudanças culturais e socioambientais promovidas dependem da dinâmica socioeconòmica, das práticas éticas e culturais e do exercicio do poder politico.

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The effects of selenium (Se) on plant metabolism have been reported in several studies triggering plant tolerance to abiotic stresses, yet, the effects of Se on coffee plants under chilling stress are unclear. This study aimed to evaluate the effects of foliar Se application on coffee seedlings submitted to chilling stress and subsequent plant recovery. Two Coffea species, Coffea arabica cv. Arara, and Coffea canephora clone 31, were submitted to foliar application of sodium selenate solution (0.4 mg plant-1) or a control foliar solution, then on day 2 plants were submitted to low temperature (10°C day/4°C night) for 2 days. After that, the temperature was restored to optimal (25°C day/20°C night) for 2 days. Leaf samples were collected three times (before, during, and after the chilling stress) to perform analyses. After the chilling stress, visual leaf injury was observed in both species; however, the damage was twofold higher in C. canephora. The lower effect of cold on C. arabica was correlated to the increase in ascorbate peroxidase and higher content of starch, sucrose, and total soluble sugars compared with C. canephora, as well as a reduction in reducing sugars and proline content during the stress and rewarming. Se increased the nitrogen and sulfur content before stress but reduced their content during low temperature. The reduced content of nitrogen and sulfur during stress indicates that they were remobilized to stem and roots. Se supply reduced the damage in C. canephora leaves by 24% compared with the control. However, there was no evidence of the Se effects on antioxidant enzymatic pathways or ROS activity during stress as previously reported in the literature. Se increased the content of catalase during the rewarming. Se foliar supply also increased starch, amino acids, and proline, which may have reduced symptom expression in C. canephora in response to low temperature. In conclusion, Se foliar application can be used as a strategy to improve coffee tolerance under low-temperature changing nutrient remobilization, carbohydrate metabolism, and catalase activity in response to rewarming stress, but C. arabica and C. canephora respond differently to chilling stress and Se supply.

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Traditional agroforestry systems (TAFS) are important areas for conserving biodiversity, ecosystems benefits and biocultural heritage, outstandingly local knowledge, management techniques, and domestication processes. These systems have adapted to environmental, social, technological, and cultural changes throughout history. However, contemporary drastic socio-environmental changes as climate variability, economic inequality, migration, among others, have caused a productive crisis, with several consequences as productive land abandonment, threaten the sustainability of TAFS and vulnerating livelihoods. In such context, the question arises of what kind of adaptations are needed to face these changes, and how access to water and land, should be managed to improve adaptation of TAFS? The study analyzes TAFS in the Tehuacán Valley, a region with high biological and cultural diversity and early signs of agriculture in Mexico, where TAFS have remained active until present. The study analyzes the capacity of TAFS to conserve biodiversity and sustain local livelihoods, despite socio-environmental threats. It is based on a political ecology approach, which proposes that socio-ecological systems degradation is linked to unequal access to land and natural resources. Looking for an integral study of adaptations of TAFS to socio-environmental changes, this study combines qualitative and historical research methodology with quantitative methods evaluating plant diversity and spatial analysis. The study findings show that differentiated access to resources, water, land, and forest, is a key factor that limits adaptation of TAFS, impacting livelihood strategies, changing management patterns, and constraining social capacities for coping with socio-environmental changes. TAFS have significantly higher species richness than forests but lower diversity. The main contribution of the study is the methodological approach looking for an integral analysis of natural resources management and biocultural conservation in agroecosystems, and the identification of the unequal access to resources, as a keystone to understand and act for improving adaptive strategies of TAFS to socio-environmental changes.

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Small-scale fisheries are critically important for livelihoods around the world, particularly in tropical regions. However, climate variability and anthropogenic climate change may seriously impact small-scale fisheries by altering the abundance and distribution of target species. Social relationships between fishery users, such as fish traders, can determine how each individual responds and is affected by changes in fisheries. These informal cooperative and competitive relationships provide access, support, and incentives for fishing and affect the distribution of benefits. Yet, individuals' actions and impacts on individuals are often the primary focus of the economic analyses informing small-scale fisheries' formal management. This focus dismisses relevant social relationships. We argue that this leads to a disconnect between reality and its model representation used in formal management, which may reduce formal fisheries management's efficiency and efficacy and potentially trigger adverse consequences. Here, we examine this argument by comparing the predictions of a simple bioeconomic fishery model with those of a social-ecological model that incorporates the dynamics of cooperative relationships between fish traders. We illustrate model outcomes using an empirical case study in the Mexican Humboldt squid fishery. We find that (1) the social-ecological model with relationship dynamics substantially improves accuracy in predicting observed fishery variables to the simple bioeconomic model. (2) Income inequality outcomes are associated with changes in cooperative trade relationships. When environmental temperature is included in the model as a driver of species production dynamics, we find that climate-driven temperature variability drives a decline in catch that, in turn, reduce fishers' income. We observe an offset of this loss in income by including cooperative relationships between fish traders (oligopoly) in the model. These relationships break down following species distribution changes and result in an increase in prices fishers receive. Finally, (3) our social-ecological model simulations show that the current fishery development program, which seeks to increase fishers' income through an increase in domestic market demand, is supported by predictions from the simple bioeconomic model, may increase income inequality between fishers and traders. Our findings highlight the real and urgent need to re-think fisheries management models in the context of small-scale fisheries and climate change worldwide to encompass social relationship dynamics. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at (10.1007/s10113-021-01747-5).

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Human actions often alter natural environments, causing homogenization of micro-habitats and, consequently, the loss or replacement of species. Our research evaluates how the effects of environmental integrity and the physical and chemical characteristics of streams influence the adult Odonata community in a region of the Amazon, in western Pará. The data were obtained in 15 streams of first and second order in the municipality of Santarém, Pará, between October and December 2014 (dry season) and between March and May 2015 (rainy season). A total of 544 specimens were collected, distributed in 23 genera, 35 species. Significant differences were observed in the composition of Odonata based on the integrity of streams, and species are replaced as the habitat integrity gradient is reduced, with species that need more preserved conditions extinct locally, making room for generalist species. However, only Psaironeura tenuissima was an indicator of more preserved sites, while Argia sp.1 and Mnesarete smaragdina were indicative of altered sites. None of the variables had any influence on the richness or abundance of Odonata.

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