High aboveground carbon stock of African tropical montane forests.

Tropical forests store 40-50 per cent of terrestrial vegetation carbon1. However, spatial variations in aboveground live tree biomass carbon (AGC) stocks remain poorly understood, in particular in tropical montane forests2. Owing to climatic and soil changes with increasing elevation3, AGC stocks are lower in tropical montane forests compared with lowland forests2. Here we assemble and analyse a dataset of structurally intact old-growth forests (AfriMont) spanning 44 montane sites in 12 African countries. We find that montane sites in the AfriMont plot network have a mean AGC stock of 149.4 megagrams of carbon per hectare (95% confidence interval 137.1-164.2), which is comparable to lowland forests in the African Tropical Rainforest Observation Network4 and about 70 per cent and 32 per cent higher than averages from plot networks in montane2,5,6 and lowland7 forests in the Neotropics, respectively. Notably, our results are two-thirds higher than the Intergovernmental Panel on Climate Change default values for these forests in Africa8. We find that the low stem density and high abundance of large trees of African lowland forests4 is mirrored in the montane forests sampled. This carbon store is endangered: we estimate that 0.8 million hectares of old-growth African montane forest have been lost since 2000. We provide country-specific montane forest AGC stock estimates modelled from our plot network to help to guide forest conservation and reforestation interventions. Our findings highlight the need for conserving these biodiverse9,10 and carbon-rich ecosystems.

Bending the curve of terrestrial biodiversity needs an integrated strategy.

Increased efforts are required to prevent further losses to terrestrial biodiversity and the ecosystem services that it  provides1,2. Ambitious targets have been proposed, such as reversing the declining trends in biodiversity3; however, just feeding the growing human population will make this a challenge4. Here we use an ensemble of land-use and biodiversity models to assess whether-and how-humanity can reverse the declines in terrestrial biodiversity caused by habitat conversion, which is a major threat to biodiversity5. We show that immediate efforts, consistent with the broader sustainability agenda but of unprecedented ambition and coordination, could enable the provision of food for the growing human population while reversing the global terrestrial biodiversity trends caused by habitat conversion. If we decide to increase the extent of land under conservation management, restore degraded land and generalize landscape-level conservation planning, biodiversity trends from habitat conversion could become positive by the mid-twenty-first century on average across models (confidence interval, 2042-2061), but this was not the case for all models. Food prices could increase and, on average across models, almost half (confidence interval, 34-50%) of the future biodiversity losses could not be avoided. However, additionally tackling the drivers of land-use change could avoid conflict with affordable food provision and reduces the environmental effects of the food-provision system. Through further sustainable intensification and trade, reduced food waste and more plant-based human diets, more than two thirds of future biodiversity losses are avoided and the biodiversity trends from habitat conversion are reversed by 2050 for almost all of the models. Although limiting further loss will remain challenging in several biodiversity-rich regions, and other threats-such as climate change-must be addressed to truly reverse the declines in biodiversity, our results show that ambitious conservation efforts and food system transformation are central to an effective post-2020 biodiversity strategy.

Prevalence of sustainable and unsustainable use of wild species inferred from the IUCN Red List of Threatened Species.

Unsustainable exploitation of wild species represents a serious threat to biodiversity and to the livelihoods of local communities and Indigenous peoples. However, managed, sustainable use has the potential to forestall extinctions, aid recovery, and meet human needs. We analyzed species-level data for 30,923 species from 13 taxonomic groups on the International Union for Conservation of Nature Red List of Threatened Species to investigate patterns of intentional biological resource use. Forty percent of species (10,098 of 25,009 species from 10 data-sufficient taxonomic groups) were used. The main purposes of use were pets, display animals, horticulture, and human consumption. Intentional use is currently contributing to elevated extinction risk for 28-29% of threatened or near threatened (NT) species (2752-2848 of 9753 species). Intentional use also affected 16% of all species used (1597-1631 of 10,098). However, 72% of used species (7291 of 10,098) were least concern, of which nearly half (3469) also had stable or improving population trends. The remainder were not documented as threatened by biological resource use, including at least 172 threatened or NT species with stable or improving populations. About one-third of species that had use documented as a threat had no targeted species management actions to directly address this threat. To improve use-related red-list data, we suggest small amendments to the relevant classification schemes and required supporting documentation. Our findings on the prevalence of sustainable and unsustainable use, and variation across taxa, can inform international policy making, including the Intergovernmental Science-Policy Platform on Biodiversity and Ecosystem Services, the Convention on Biological Diversity, and the Convention on International Trade in Endangered Species.

Predominio del Uso Sustentable y No Sustentable de Especies Silvestres Inferido a partir de la Lista Roja de Especies Amenazadas de la UICN Resumen La explotación insostenible de especies silvestres representa una verdadera amenaza para la biodiversidad y el sustento de las comunidades locales y los pueblos indígenas. Sin embargo, el uso sostenible gestionado tiene el potencial para prevenir extinciones, auxiliar en la recuperación y satisfacer las necesidades humanas. Analizamos los datos a nivel de especie correspondientes a 30,923 especies de 13 grupos taxonómicos localizados en la Lista Roja de Especies Amenazadas de la Unión Internacional para la Conservación de la Naturaleza (UICN) para investigar los patrones del uso intencional de recursos biológicos. Usamos el 40% de las especies analizadas (10,098 de 25,009 especies pertenecientes a diez grupos taxonómicos con suficiente información). Los principales motivos para el uso de vida silvestre fueron como mascotas, animales de exhibición, horticultura y consumo humano. El uso intencional está actualmente contribuyendo a un riesgo elevado de extinción para 28 - 29% de las especies amenazadas o casi amenazadas (NT) (2,752 - 2,848 de 9,753 especies). El uso intencional también afectó al 16% de todas las especies utilizadas (1,597 - 1,631 de 10,098). Sin embargo, el 72% de las especies utilizadas (7,291 de 10, 098) pertenecen a la categoría de preocupación menor, de las cuales casi la mitad (3,469) también contaban con tendencias poblacionales estables o de mejoría. Las especies restantes no estaban documentadas como amenazadas por el uso de recursos biológicos, incluyendo al menos 172 especies amenazadas o NT con poblaciones estables o en aumento. Casi un tercio de las especies que tienen documentado el uso como una amenaza no cuentan con acciones de manejo para abordar directamente esta amenaza. Para mejorar la información de la lista roja relacionada con el uso, sugerimos pequeñas modificaciones a los esquemas relevantes de clasificación y la documentación de apoyo requerida. Nuestros descubrimientos sobre el predominio del uso sustentable y no sustentable, y la variación entre taxones, puede orientar la formulación de políticas internacionales, incluyendo a la Plataforma Intergubernamental de Políticas Científicas sobre Biodiversidad y Servicios Ecosistémicos, el Convenio sobre la Diversidad Biológica y la Convención sobre el Comercio Internacional de Especies Amenazadas.

A global-level assessment of the effectiveness of protected areas at resisting anthropogenic pressures.

One-sixth of the global terrestrial surface now falls within protected areas (PAs), making it essential to understand how far they mitigate the increasing pressures on nature which characterize the Anthropocene. In by far the largest analysis of this question to date and not restricted to forested PAs, we compiled data from 12,315 PAs across 152 countries to investigate their ability to reduce human pressure and how this varies with socioeconomic and management circumstances. While many PAs show positive outcomes, strikingly we find that compared with matched unprotected areas, PAs have on average not reduced a compound index of pressure change over the past 15 y. Moreover, in tropical regions average pressure change from cropland conversion has increased inside PAs even more than in matched unprotected areas. However, our results also confirm previous studies restricted to forest PAs, where pressures are increasing, but less than in counterfactual areas. Our results also show that countries with high national-level development scores have experienced lower rates of pressure increase over the past 15 y within their PAs compared with a matched outside area. Our results caution against the rapid establishment of new PAs without simultaneously addressing the conditions needed to enable their success.

Linking global drivers of agricultural trade to on-the-ground impacts on biodiversity.

Consumption of globally traded agricultural commodities like soy and palm oil is one of the primary causes of deforestation and biodiversity loss in some of the world's most species-rich ecosystems. However, the complexity of global supply chains has confounded efforts to reduce impacts. Companies and governments with sustainability commitments struggle to understand their own sourcing patterns, while the activities of more unscrupulous actors are conveniently masked by the opacity of global trade. We combine state-of-the-art material flow, economic trade, and biodiversity impact models to produce an innovative approach for understanding the impacts of trade on biodiversity loss and the roles of remote markets and actors. We do this for the production of soy in the Brazilian Cerrado, home to more than 5% of the world´s species. Distinct sourcing patterns of consumer countries and trading companies result in substantially different impacts on endemic species. Connections between individual buyers and specific hot spots explain the disproportionate impacts of some actors on endemic species and individual threatened species, such as the particular impact of European Union consumers on the recent habitat losses for the iconic giant anteater (Myrmecophaga tridactyla). In making these linkages explicit, our approach enables commodity buyers and investors to target their efforts much more closely to improve the sustainability of their supply chains in their sourcing regions while also transforming our ability to monitor the impact of such commitments over time.

The Concept, Practice, Application, and Results of Locally Based Monitoring of the Environment.

Locally based monitoring is typically undertaken in areas in which communities have a close attachment to their natural resource base. We present a summary of work to develop a theoretical and practical understanding of locally based monitoring and we outline tests of this approach in research and practice over the past 20 years. Our tests show that locally based monitoring delivers credible data at local scale independent of external experts and can be used to inform local and national decision making within a short timeframe. We believe that monitoring conducted by and anchored in communities will gain in importance where scientist-led monitoring is sparse or too expensive to sustain and for ecosystem attributes in cases in which remote sensing cannot provide credible data. The spread of smartphone technology and online portals will further enhance the importance and usefulness of this discipline.

Perspectives on area-based conservation and its meaning for future biodiversity policy.

During 2021, Parties to the Convention on Biological Diversity (CBD) are expected to meet in Kunming, China, to agree on a new global biodiversity framework aimed at halting and reversing biodiversity loss, encouraging the sustainable use of biodiversity, and ensuring the equitable sharing of its benefits. As the post-2020 global biodiversity framework evolves, parties to the convention are being exposed to a range of perspectives on the conservation and sustainable use of biodiversity, relating to the future framework as a whole or to aspects of it. Area-based conservation measures are one such aspect, and there are diverse perspectives on how new targets might be framed in relation to these measures. These perspectives represent different outlooks on the relationship between human and nonhuman life on Earth. However, in most cases there is a lack of clarity on how they would be implemented in practice, the implications this would have for biodiversity and human well-being, and how they would contribute to achieving the 2050 Vision for Biodiversity of "living in harmony with nature." We sought to clarify these issues by summarizing some of these perspectives in relation to the future of area-based biodiversity conservation. We identified these perspectives through a review of the literature and expert consultation workshops and compiled them into 4 main groups: Aichi+, ambitious area-based conservation perspectives, new conservation, and whole-earth conservation. We found that although the perspectives Aichi+ and whole earth are in some cases at odds with one another, they also have commonalities, and all perspectives have elements that can contribute to developing and implementing the post-2020 global biodiversity framework and achieving the longer term CBD 2050 Vision.

Perspectivas de la Conservación Basada en el Área y su Significado para las Futuras Políticas de Biodiversidad Resumen Durante 2021, se espera que las partes miembro del Convenio sobre la Diversidad Biológica (CBD) se reúnan en Kunming, China, para acordar un nuevo marco de trabajo global para la biodiversidad enfocado en detener y revertir la pérdida de la biodiversidad, promover el uso sustentable de la biodiversidad y asegurar la repartición equitativa de sus beneficios. Conforme evoluciona el marco de trabajo global para la biodiversidad post-2020, las partes miembro del convenio están conociendo una gama de perspectivas de la conservación y el uso sustentable de la biodiversidad, relacionándolas con el futuro marco de trabajo en su totalidad o sólo con algunos aspectos del marco de trabajo. Las medidas de conservación basadas en el área son uno de dichos aspectos y existen diversas perspectivas sobre cómo los nuevos objetivos podrían estar enmarcados en relación a estas medidas. Estas perspectivas representan diferentes puntos de vista sobre la relación entre la vida humana y no humana en la Tierra. Sin embargo, en la mayoría de los casos existe una falta de claridad sobre cómo se implementarían en la práctica, las implicaciones que ésto tendría para la biodiversidad y el bienestar humano y cómo contribuirían para alcanzar la Visión para la Biodiversidad 2050 de "vivir en armonía con la naturaleza". Buscamos aclarar estos temas al resumir algunas de estas perspectivas en relación al futuro de la conservación de la biodiversidad basada en el área. Identificamos estas perspectivas por medio de una revisión de la literatura y talleres de consulta a expertos y las compilamos en cuatro grupos principales: Aichi+, perspectivas ambiciosas de conservación basada en el área, conservación nueva y conservación del mundo entero. Descubrimos que aunque las perspectivas Aichi+ y conservación del mundo entero entran en conflicto en algunos casos, también tienen puntos comunes, y todas las perspectivas tienen elementos que pueden contribuir al desarrollo e implementación del marco de trabajo global para la biodiversidad post-2020 y para alcanzar la Visión CBD 2050 de mayor plazo.

The importance of Indigenous Peoples' lands for the conservation of terrestrial mammals.

Indigenous Peoples' lands cover over one-quarter of Earth's surface, a significant proportion of which is still free from industrial-level human impacts. As a result, Indigenous Peoples and their lands are crucial for the long-term persistence of Earth's biodiversity and ecosystem services. Yet, information on species composition on these lands globally remains largely unknown. We conducted the first comprehensive analysis of terrestrial mammal composition across mapped Indigenous lands based on data on area of habitat (AOH) for 4460 mammal species assessed by the International Union for Conservation of Nature. We overlaid each species' AOH on a current map of Indigenous lands and found that 2695 species (60% of assessed mammals) had ≥10% of their ranges on Indigenous Peoples' lands and 1009 species (23%) had >50% of their ranges on these lands. For threatened species, 473 (47%) occurred on Indigenous lands with 26% having >50% of their habitat on these lands. We also found that 935 mammal species (131 categorized as threatened) had ≥ 10% of their range on Indigenous Peoples' lands that had low human pressure. Our results show how important Indigenous Peoples' lands are to the successful implementation of conservation and sustainable development agendas worldwide.

La Importancia de las Tierras de los Pueblos Indígenas para la Conservación de los Mamíferos Terrestres Resumen Las tierras pertenecientes a pueblos indígenas cubren más de un cuarto de la superficie del planeta, una proporción importante que se encuentra aún libre de impactos humanos a nivel industrial. Como resultado, los pueblos indígenas y sus tierras son cruciales para la persistencia a largo plazo de la biodiversidad en la Tierra y de los servicios ecosistemicos. Sin embargo, la información sobre la composición de especies en estas tierras a nivel mundial todavía permanece desconocida en su mayoría. Realizamos el primer análisis integral de la composición de mamíferos terrestres a lo largo de las tierras indígenas mapeadas con base en los datos sobre el área del hábitat (ADH) de 4,460 especies de mamíferos valorados por la Unión Internacional para la Conservación de la Naturaleza. Sobrepusimos el ADH de cada especie en un mapa actual de tierras indígenas y encontramos que 2,695 especies (60% de los mamíferos valorados) tienen ≥10% de su distribución dentro de tierras de pueblos indígenas y que 1,009 especies (23%) tienen >50% de su distribución dentro de estas tierras. De las especies amenazadas, 473 (47%) ocurrieron en tierras indígenas.También descubrimos que 935 especies de mamíferos (131 categorizadas como amenazadas) tienen ≥ 10% de su distribución dentro de tierras de pueblos indígenas con baja presión humana. Nuestros resultados muestran cuán importantes son las tierras de los pueblos indígenas para la implementación exitosa de la conservación y las agendas globales de desarrollo sustentable.

Dynamics in the global protected-area estate since 2004.

Nations of the world have committed to a number of goals and targets to address global environmental challenges. Protected areas have for centuries been a key strategy in conservation and play a major role in addressing current challenges. The most important tool used to track progress on protected-area commitments is the World Database on Protected Areas (WDPA). Periodic assessments of the world's protected-area estate show steady growth over the last 2 decades. However, the current method, which uses the latest version of the WDPA, does not show the true dynamic nature of protected areas over time and does not provide information on sites removed from the WDPA. In reality, this method can only show growth or remain stable. We used GIS tools in an approach to assess protected-area change over time based on 12 temporally distinct versions of the WDPA that quantify area added and removed from the WDPA annually from 2004 to 2016. Both the narrative of continual growth of protected area and the counter-narrative of protected area removal were overly simplistic. The former because growth was almost entirely in the marine realm and the latter because some areas removed were reprotected in later years. On average 2.5 million km2 was added to the WDPA annually and 1.1 million km2 was removed. Reasons for the inclusion and removal of protected areas in the WDPA database were in part due to data-quality issues but also to on-the-ground changes. To meet the 17% protected-area component of Aichi Biodiversity Target 11 by 2020, which stood at 14.7% in 2016, either the rate of protected-area removal must decrease or the rate of protected-area designation and addition to the WDPA must increase.

Dinámica de los Bienes de las Áreas Protegidas desde 2004 Resumen Países alrededor del mundo se han comprometido con un número de metas y objetivos para tratar los retos ambientales mundiales. Las áreas protegidas han funcionado durante siglos como una estrategia clave en la conservación y juegan un papel importante en cómo se manejan los retos actuales. La herramienta más importante que se usa para rastrear el progreso de los compromisos con las áreas protegidas es la Base de Datos Mundial de las Áreas Protegidas (WDPA, en inglés). Las evaluaciones periódicas de los bienes de las áreas protegidas muestran un crecimiento constante durante las últimas dos décadas. Sin embargo, el método actual, que usa la versión más reciente de la WDPA, no muestra la verdadera naturaleza dinámica de las áreas protegidas a lo largo del tiempo y no proporciona información sobre sitios que han sido removidos de la WDPA. En realidad este método sólo puede mostrar crecimiento o permanecer estable. Usamos herramientas de SIG en una estrategia para evaluar el cambio de las áreas protegidas a lo largo del tiempo con base en doce versiones temporalmente distintas de la WDPA que cuantifican las áreas añadidas o removidas de la WDPA anualmente desde 2004 hasta 2016. Tanto la narrativa del crecimiento continuo de un área protegida como la contra-narrativa de la eliminación de un área protegida fueron exageradamente simplistas. La primera se debe a que el crecimiento ocurrió casi en su mayoría en el dominio marino y la segunda a que algunas áreas eliminadas fueron reprotegidas años después. En promedio se añadieron 2.5 millones de km2 a la WDPA anualmente y 1.1 millones de km2 fueron removidos. Las razones para la inclusión y la eliminación de las áreas protegidas de la base de datos de la WDPA se debieron en parte a temas de calidad de datos pero también a cambios hechos sobre la marcha. Para lograr el 17% del componente de áreas protegidas del Objetivo 11 de Biodiversidad de Aichi para el 2020, el cual se encontraba al 14.7% en 2016, se debe disminuir la tasa de eliminación de áreas protegidas o se debe incrementar la tasa de designación y suma de áreas protegidas a la WDPA.

Improving collaboration in the implementation of global biodiversity conventions.

Eight conventions make up the biodiversity cluster of multilateral environmental agreements (MEAs) that provide the critical international legal framework for the conservation and sustainable use of nature. However, concerns about the rate of implementation of the conventions at the national level have triggered discussions about the effectiveness of these MEAs in halting the loss of biodiversity. Two main concerns have emerged: lack of capacity and resources and lack of coherence in implementing multiple conventions. We focused on the latter and considered the mechanisms by which international conventions are translated into national policy. Specifically, we examined how the Strategic Plan for Biodiversity 2011-2020 and the associated Aichi Biodiversity Targets have functioned as a unifying grand plan for biodiversity conservation. This strategic plan has been used to coordinate and align targets to promote and enable more effective implementation across all biodiversity-related conventions. Results of a survey of 139 key stakeholders from 88 countries suggests streamlining across ministries and agencies, improved coordination mechanisms with all relevant stakeholders, and better knowledge sharing between conventions could improve cooperation among biodiversity-related conventions. The roadmap for improving synergies among conventions agreed to at the 13th Convention on Biological Diversity's Conference of Parties in 2016 includes actions such as mechanisms to avoid duplication in national reporting and monitoring on conventions and capacity building related to information and knowledge sharing. We suggest the scientific community can actively engage and contribute to the policy process by establishing a science-policy platform to address knowledge gaps; improving data gathering, reporting, and monitoring; developing indicators that adequately support implementation of national plans and strategies; and providing evidence-based recommendations to policy makers. The latter will be particularly important as 2020 approaches and work to develop a new biodiversity agenda for the next decade is beginning.

Mejora en la Colaboración en la Implementación de las Convenciones Mundiales sobre la Biodiversidad Resumen Ocho convenciones son las que forman la agrupación multilateral de acuerdos ambientales (MEAs, en inglés), los cuales proporcionan el marco de trabajo legal importante para la conservación y el uso sustentable de la naturaleza. Sin embargo, la preocupación por la tasa de implementación de estas convenciones a nivel nacional ha disparado discusiones sobre la efectividad de estas MEAs para detener la pérdida de la biodiversidad. Han surgido dos preocupaciones principales: la falta de capacidad y recursos y la falta de coherencia en la implementación de múltiples convenciones. Nos enfocamos en la segunda y consideramos los mecanismos mediante los cuales las convenciones internacionales se transforman en reglamentos y políticas nacionales. En específico, examinamos cómo el Plan Estratégico para la Biodiversidad 2011 - 2020 y los Objetivos de Biodiversidad de Aichi asociados han funcionado como un gran plan unificador para la conservación de la biodiversidad. Este plan estratégico se ha usado para coordinar y alinear los objetivos para promover y habilitar una implementación más efectiva a lo largo de todas las convenciones relacionadas con la biodiversidad. Los resultados de una encuesta entre 139 accionistas clave de 88 países sugieren la optimización en los ministerios y en las agencias, una coordinación mejorada de los mecanismos entre todos los accionistas relevantes, y una mejor partición del conocimiento entre las convenciones podría aumentar la cooperación entre las convenciones relacionadas con la biodiversidad. La hoja de ruta para mejorar las sinergias entre las convenciones, acordada en la Conferencia de Participantes de la 13ra Convención sobre la Diversidad Biológica en 2016, incluye acciones como los mecanismos para evitar la duplicación de reportes y monitoreos nacionales sobre las convenciones y la capacidad de construcción relacionada con la partición de la información y el conocimiento. Sugerimos que la comunidad científica pueda participar activamente y contribuir al proceso de políticas al establecer una plataforma política-científica que resuelva los vacíos en el conocimiento; mejore la recolección, reporte y monitoreo de datos, desarrolle indicadores que respalden adecuadamente a la implementación de planes y estrategias nacionales; y proporcione recomendaciones basadas en evidencia para los políticos. La última acción será de particular importancia conforme se aproxima el 2020 y se inicie la labor por desarrollar una nueva agenda de biodiversidad para la siguiente década.

Relating characteristics of global biodiversity targets to reported progress.

To inform governmental discussions on the nature of a revised Strategic Plan for Biodiversity of the Convention on Biological Diversity (CBD), we reviewed the relevant literature and assessed the framing of the 20 Aichi Biodiversity Targets in the current strategic plan. We asked international experts from nongovernmental organizations, academia, government agencies, international organizations, research institutes, and the CBD to score the Aichi Targets and their constituent elements against a set of specific, measurable, ambitious, realistic, unambiguous, scalable, and comprehensive criteria (SMART based, excluding time bound because all targets are bound to 2015 or 2020). We then investigated the relationship between these expert scores and reported progress toward the target elements by using the findings from 2 global progress assessments (Global Biodiversity Outlook and the Intergovernmental Science-Policy Platform on Biodiversity and Ecosystem Services). We analyzed the data with ordinal logistic regressions. We found significant positive relationships (p < 0.05) between progress and the extent to which the target elements were perceived to be measurable, realistic, unambiguous, and scalable. There was some evidence of a relationship between progress and specificity of the target elements, but no relationship between progress and ambition. We are the first to show associations between progress and the extent to which the Aichi Targets meet certain SMART criteria. As negotiations around the post-2020 biodiversity framework proceed, decision makers should strive to ensure that new or revised targets are effectively structured and clearly worded to allow the translation of targets into actionable policies that can be successfully implemented nationally, regionally, and globally.

Relación de las Características de los Objetivos Mundiales de Biodiversidad con el Progreso Reportado Resumen Para informar las discusiones gubernamentales sobre la naturaleza de una revisión del Plan Estratégico para la Biodiversidad del Convenio sobre la Diversidad Biológica (CBD, en inglés), revisamos la literatura relevante y evaluamos el marco de 20 Objetivos de Biodiversidad de Aichi en el plan estratégico actual. Le pedimos a expertos internacionales de organizaciones no gubernamentales, de la academia, de agencias gubernamentales, organizaciones internacionales, de institutos de investigación y de la CBD que puntuaran los Objetivos de Aichi y sus elementos constituyentes frente a un conjunto de criterios específicos, medibles, ambiciosos, realistas (basados en SMART [las iniciales en inglés] y excluyendo aquellos limitados por el tiempo, pues todos los objetivos están limitados al 2015 o al 2020), inequívocos, expansibles y completos (excluyendo aquellos limitados por el tiempo). Después investigamos la relación entre los puntajes de estos expertos y el progreso reportado hacia los elementos objetivo usando los resultados de dos valoraciones mundiales del progreso (el Pronóstico Mundial de la Biodiversidad y la Plataforma Intergubernamental de Ciencia y Política sobre la Biodiversidad y los Servicios Ambientales). Analizamos los datos con regresiones logísticas ordinales. Encontramos relaciones positivas significativas (p < 0.05) entre el progreso y el alcance al que fueron percibidos como medibles, realistas, inequívocos y expansibles los elementos objetivo. Hubo algo de evidencia de la relación entre el progreso y la ambición. Somos los primeros en mostrar las asociaciones entre el progreso y la extensión hasta la que los Objetivos de Aichi cumplen con ciertos criterios SMART. Conforme proceden las negociaciones en torno al marco de trabajo de biodiversidad post-2020, quienes toman las decisiones deberían esforzarse por asegurar que los objetivos nuevos o revisados estén estructurados efectivamente y redactados claramente para permitir la traducción de los objetivos hacia políticas factibles que puedan implementarse exitosamente a nivel nacional, regional y mundial.

Harvesting fodder trees in montane forests in Kenya: species, techniques used and impacts.

There has been an increasing interest in fodder trees and their potential to help the rural poor. However, few studies have addressed the ecological impacts of fodder tree harvesting. We investigated the species harvested and the techniques used, and the effects of fodder harvesting on (1) species' populations and (2) forest carbon stocks in three montane forests in Kenya. Focus-group discussions were organized in 36 villages to determine which species were harvested and with which techniques. Field observations were made on vegetation plots: stem diameter, tree height, species and extent of harvest were recorded. Carbon stocks were calculated using an allometric equation with (1) observed height of harvested trees, and (2) potential height estimated with a power model, and results were compared. Eight tree species were commonly harvested for fodder using different techniques (some branches, main stem, most branches except stem apex). Fodder harvesting (together with other uses for some species) negatively affected one species populations (Olea europaea), it did not negatively affect four (Drypetes gerrardii, Gymnosporia heterophylla, Pavetta gardeniifolia, Xymalos monospora), and more information is needed for three species (Olea capensis, Prunus africana, Rinorea convallarioides). Fodder harvesting did not significantly reduce forest carbon stocks, suggesting that local communities could continue using these fodder trees if a carbon project is established. Among the fodder species studied, X. monospora could be used in reforestation programs, as it has multiple uses and can withstand severe pruning. Although our study is only a snapshot, it is a baseline which can be used to monitor changes in fodder harvesting and its impacts related to increasing droughts in northern Kenya and increasing human populations.

An Ecoregion-Based Approach to Protecting Half the Terrestrial Realm.

We assess progress toward the protection of 50% of the terrestrial biosphere to address the species-extinction crisis and conserve a global ecological heritage for future generations. Using a map of Earth's 846 terrestrial ecoregions, we show that 98 ecoregions (12%) exceed Half Protected; 313 ecoregions (37%) fall short of Half Protected but have sufficient unaltered habitat remaining to reach the target; and 207 ecoregions (24%) are in peril, where an average of only 4% of natural habitat remains. We propose a Global Deal for Nature-a companion to the Paris Climate Deal-to promote increased habitat protection and restoration, national- and ecoregion-scale conservation strategies, and the empowerment of indigenous peoples to protect their sovereign lands. The goal of such an accord would be to protect half the terrestrial realm by 2050 to halt the extinction crisis while sustaining human livelihoods.

Land cover change and carbon emissions over 100 years in an African biodiversity hotspot.

Agricultural expansion has resulted in both land use and land cover change (LULCC) across the tropics. However, the spatial and temporal patterns of such change and their resulting impacts are poorly understood, particularly for the presatellite era. Here, we quantify the LULCC history across the 33.9 million ha watershed of Tanzania's Eastern Arc Mountains, using geo-referenced and digitized historical land cover maps (dated 1908, 1923, 1949 and 2000). Our time series from this biodiversity hotspot shows that forest and savanna area both declined, by 74% (2.8 million ha) and 10% (2.9 million ha), respectively, between 1908 and 2000. This vegetation was replaced by a fivefold increase in cropland, from 1.2 million ha to 6.7 million ha. This LULCC implies a committed release of 0.9 Pg C (95% CI: 0.4-1.5) across the watershed for the same period, equivalent to 0.3 Mg C ha(-1)  yr(-1) . This is at least threefold higher than previous estimates from global models for the same study area. We then used the LULCC data from before and after protected area creation, as well as from areas where no protection was established, to analyse the effectiveness of legal protection on land cover change despite the underlying spatial variation in protected areas. We found that, between 1949 and 2000, forest expanded within legally protected areas, resulting in carbon uptake of 4.8 (3.8-5.7) Mg C ha(-1) , compared to a committed loss of 11.9 (7.2-16.6) Mg C ha(-1) within areas lacking such protection. Furthermore, for nine protected areas where LULCC data are available prior to and following establishment, we show that protection reduces deforestation rates by 150% relative to unprotected portions of the watershed. Our results highlight that considerable LULCC occurred prior to the satellite era, thus other data sources are required to better understand long-term land cover trends in the tropics.

Mapping change in human pressure globally on land and within protected areas.

It is widely accepted that the main driver of the observed decline in biological diversity is increasing human pressure on Earth's ecosystems. However, the spatial patterns of change in human pressure and their relation to conservation efforts are less well known. We developed a spatially and temporally explicit map of global change in human pressure over 2 decades between 1990 and 2010 at a resolution of 10 km(2) . We evaluated 22 spatial data sets representing different components of human pressure and used them to compile a temporal human pressure index (THPI) based on 3 data sets: human population density, land transformation, and electrical power infrastructure. We investigated how the THPI within protected areas was correlated to International Union for Conservation of Nature (IUCN) management categories and the human development index (HDI) and how the THPI was correlated to cumulative pressure on the basis of the original human footprint index. Since the early 1990s, human pressure increased 64% of the terrestrial areas; the largest increases were in Southeast Asia. Protected areas also exhibited overall increases in human pressure, the degree of which varied with location and IUCN management category. Only wilderness areas and natural monuments (management categories Ib and III) exhibited decreases in pressure. Protected areas not assigned any category exhibited the greatest increases. High HDI values correlated with greater reductions in pressure across protected areas, while increasing age of the protected area correlated with increases in pressure. Our analysis is an initial step toward mapping changes in human pressure on the natural world over time. That only 3 data sets could be included in our spatio-temporal global pressure map highlights the challenge to measuring pressure changes over time.

Ecological and social outcomes of a new protected area in Tanzania.

Balancing ecological and social outcomes of conservation actions is recognized in global conservation policy but is challenging in practice. Compensation to land owners or users for foregone assets has been proposed by economists as an efficient way to mitigate negative social impacts of human displacement from protected areas. Joint empirical assessments of the conservation and social impacts of protected area establishment involving compensation payments are scarce. We synthesized social and biological studies related to the establishment of the Derema forest corridor in Tanzania's biodiverse East Usambara Mountains. This lengthy conservation process involved the appropriation of approximately 960 ha of native canopy agroforest and steep slopes for the corridor and monetary compensation to more than 1100 claimants in the surrounding villages. The overarching goals from the outset were to conserve ecological processes while doing no harm to the local communities. We evaluated whether these goals were achieved by analyzing 3 indicators of success: enhancement of forest connectivity, improvement of forest condition, and mitigation of negative impacts on local people's livelihoods. Indicators of forest connectivity and conditions were enhanced through reductions of forest loss and exotic species and increases in native species and canopy closure. Despite great efforts by national and international organizations, the intervention failed to mitigate livelihood losses especially among the poorest people. The Derema case illustrates the challenges of designing and implementing compensation schemes for conservation-related displacement of people.

Status and trends in the international wildlife trade in Chameleons with a focus on Tanzania.

Chameleons (family Chamaeleonidae) are a distinctive group of reptiles, mainly found in Africa, which have high local endemism and face significant threats from the international wildlife trade. We review the scale and structure of international chameleon trade, with a focus on collection in and exports from Tanzania; a hotspot of chameleon diversity. Analysis used data from the CITES Trade Database 2000-2019, combined with assessment of online trade, and on-the-ground surveys in Tanzania in 2019. Between 2000 and 2019, 1,128,776 live chameleons from 108 species were reported as exported globally, with 193,093 of these (from 32 species) exported by Tanzania. Both global and Tanzanian chameleon exports declined across the study period, driven by decreased trade in generalist genera. Whilst the proportion of captive-bred individuals increased across time for the generalist taxa, the majority of range-restricted taxa in trade remained largely wild-sourced. For Tanzanian exports, 41% of chameleons were from one of the 23 endemic species, and 10 of the 12 Tanzanian endemic species in trade are categorised as threatened with extinction by IUCN. In terms of online trade, of the 42 Tanzanian species assessed, there was evidence of online sale for 83.3% species, and 69% were actively for sale with prices listed. Prices were on average highest for Trioceros species, followed by Kinyongia, Rieppeleon, Rhampholeon, and Chameleo. Field work in Tanzania provided evidence that the historic harvest of endemic chameleon species has been higher than the quantities of these species reported as exported by Tanzania in their annual trade reports to CITES. However, we found no field evidence for trade in 2020 and 2021, in line with Tanzanian regulations that applied a blanket ban on all exports of live wild animals. Literature evidence, however, suggests that illegal trade continued to Europe from seizures of Tanzanian chameleon species in Austria in 2021.

Nature Forest Reserves in Tanzania and their importance for conservation.

Since 1997 Tanzania has undertaken a process to identify and declare a network of Nature Forest Reserves (NFRs) with high biodiversity values, from within its existing portfolio of national Forest Reserves, with 16 new NFRs declared since 2015. The current network of 22 gazetted NFRs covered 948,871 hectares in 2023. NFRs now cover a range of Tanzanian habitat types, including all main forest types-wet, seasonal, and dry-as well as wetlands and grasslands. NFRs contain at least 178 of Tanzania's 242 endemic vertebrate species, of which at least 50% are threatened with extinction, and 553 Tanzanian endemic plant taxa (species, subspecies, and varieties), of which at least 50% are threatened. NFRs also support 41 single-site endemic vertebrate species and 76 single-site endemic plant taxa. Time series analysis of management effectiveness tracking tool (METT) data shows that NFR management effectiveness is increasing, especially where donor funds have been available. Improved management and investment have resulted in measurable reductions of some critical threats in NFRs. Still, ongoing challenges remain to fully contain issues of illegal logging, charcoal production, firewood, pole-cutting, illegal hunting and snaring of birds and mammals, fire, wildlife trade, and the unpredictable impacts of climate change. Increased tourism, diversified revenue generation and investment schemes, involving communities in management, and stepping up control measures for remaining threats are all required to create a network of economically self-sustaining NFRs able to conserve critical biodiversity values.

Predictable waves of sequential forest degradation and biodiversity loss spreading from an African city.

Tropical forest degradation emits carbon at a rate of approximately 0.5 Pgxy(-1), reduces biodiversity, and facilitates forest clearance. Understanding degradation drivers and patterns is therefore crucial to managing forests to mitigate climate change and reduce biodiversity loss. Putative patterns of degradation affecting forest stocks, carbon, and biodiversity have variously been described previously, but these have not been quantitatively assessed together or tested systematically. Economic theory predicts a systematic allocation of land to its highest use value in response to distance from centers of demand. We tested this theory to see if forest exploitation would expand through time and space as concentric waves, with each wave targeting lower value products. We used forest data along a transect from 10 to 220 km from Dar es Salaam (DES), Tanzania, collected at two points in time (1991 and 2005). Our predictions were confirmed: high-value logging expanded 9 kmxy(-1), and an inner wave of lower value charcoal production 2 kmxy(-1). This resource utilization is shown to reduce the public goods of carbon storage and species richness, which significantly increased with each kilometer from DES [carbon, 0.2 Mgxha(-1); 0.1 species per sample area (0.4 ha)]. Our study suggests that tropical forest degradation can be modeled and predicted, with its attendant loss of some public goods. In sub-Saharan Africa, an area experiencing the highest rate of urban migration worldwide, coupled with a high dependence on forest-based resources, predicting the spatiotemporal patterns of degradation can inform policies designed to extract resources without unsustainably reducing carbon storage and biodiversity.

Protected areas reduce deforestation and degradation and enhance woody growth across African woodlands.

Protected areas are increasingly promoted for their capacity to sequester carbon, alongside biodiversity benefits. However, we have limited understanding of whether they are effective at reducing deforestation and degradation, or promoting vegetation growth, and the impact that this has on changes to aboveground woody carbon stocks. Here we present a new satellite radar-based map of vegetation carbon change across southern Africa's woodlands and combine this with a matching approach to assess the effect of protected areas on carbon dynamics. We show that protection has a positive effect on aboveground carbon, with stocks increasing faster in protected areas (+0.53% per year) compared to comparable lands not under protection (+0.08% per year). The positive effect of protection reflects lower rates of deforestation (-39%) and degradation (-25%), as well as a greater prevalence of vegetation growth (+12%) inside protected lands. Areas under strict protection had similar outcomes to other types of protection after controlling for differences in location, with effect scores instead varying more by country, and the level of threat. These results highlight the potential for protected areas to sequester aboveground carbon, although we caution that in some areas this may have negative impacts on biodiversity, and human wellbeing.