Agriculture and climate change are reshaping insect biodiversity worldwide.

Several previous studies have investigated changes in insect biodiversity, with some highlighting declines and others showing turnover in species composition without net declines1-5. Although research has shown that biodiversity changes are driven primarily by land-use change and increasingly by climate change6,7, the potential for interaction between these drivers and insect biodiversity on the global scale remains unclear. Here we show that the interaction between indices of historical climate warming and intensive agricultural land use is associated with reductions of almost 50% in the abundance and 27% in the number of species within insect assemblages relative to those in less-disturbed habitats with lower rates of historical climate warming. These patterns are particularly evident in the tropical realm, whereas some positive responses of biodiversity to climate change occur in non-tropical regions in natural habitats. A high availability of nearby natural habitat often mitigates reductions in insect abundance and richness associated with agricultural land use and substantial climate warming but only in low-intensity agricultural systems. In such systems, in which high levels (75% cover) of natural habitat are available, abundance and richness were reduced by 7% and 5%, respectively, compared with reductions of 63% and 61% in places where less natural habitat is present (25% cover). Our results show that insect biodiversity will probably benefit from mitigating climate change, preserving natural habitat within landscapes and reducing the intensity of agriculture.

Zoonotic host diversity increases in human-dominated ecosystems.

Land use change-for example, the conversion of natural habitats to agricultural or urban ecosystems-is widely recognized to influence the risk and emergence of zoonotic disease in humans1,2. However, whether such changes in risk are underpinned by predictable ecological changes remains unclear. It has been suggested that habitat disturbance might cause predictable changes in the local diversity and taxonomic composition of potential reservoir hosts, owing to systematic, trait-mediated differences in species resilience to human pressures3,4. Here we analyse 6,801 ecological assemblages and 376 host species worldwide, controlling for research effort, and show that land use has global and systematic effects on local zoonotic host communities. Known wildlife hosts of human-shared pathogens and parasites overall comprise a greater proportion of local species richness (18-72% higher) and total abundance (21-144% higher) in sites under substantial human use (secondary, agricultural and urban ecosystems) compared with nearby undisturbed habitats. The magnitude of this effect varies taxonomically and is strongest for rodent, bat and passerine bird zoonotic host species, which may be one factor that underpins the global importance of these taxa as zoonotic reservoirs. We further show that mammal species that harbour more pathogens overall (either human-shared or non-human-shared) are more likely to occur in human-managed ecosystems, suggesting that these trends may be mediated by ecological or life-history traits that influence both host status and tolerance to human disturbance5,6. Our results suggest that global changes in the mode and the intensity of land use are creating expanding hazardous interfaces between people, livestock and wildlife reservoirs of zoonotic disease.

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.

Assessing the global vulnerability of dryland birds to heatwaves.

As global average surface temperature increases, extreme climatic events such as heatwaves are becoming more frequent and intense, which can drive biodiversity responses such as rapid population declines and/or shifts in species distributions and even local extirpations. However, the impacts of extreme climatic events are largely ignored in conservation plans. Birds are known to be susceptible to heatwaves, especially in dryland ecosystems. Understanding which birds are most vulnerable to heatwaves, and where these birds occur, can offer a scientific basis for adaptive management and conservation. We assessed the relative vulnerability of 1196 dryland bird species to heatwaves using a trait-based approach. Among them, 888 bird species are estimated to be vulnerable to heatwaves (170 highly vulnerable, eight extremely vulnerable), of which ~91% are currently considered non-threatened by the IUCN, which suggests that many species will likely become newly threatened with intensifying climate change. We identified the top three hotspot areas of heatwave-vulnerable species in Australia (208 species), Southern Africa (125 species) and Eastern Africa (99 species). Populations of vulnerable species recorded in the Living Planet Database were found to be declining significantly faster than those of non-vulnerable species (p = .048) after heatwaves occurred. In contrast, no significant difference in population trends between vulnerable and non-vulnerable species was detected when no heatwave occurred (p = .34). This suggests that our vulnerability framework correctly identified vulnerable species and that heatwaves are already impacting the population trends of these species. Our findings will help prioritize heatwave-vulnerable birds in dryland ecosystems in risk mitigation and adaptation management as the frequency of heatwaves accelerates in the coming decades.

Species life-history strategies affect population responses to temperature and land-cover changes.

Human-induced environmental changes have a direct impact on species populations, with some species experiencing declines while others display population growth. Understanding why and how species populations respond differently to environmental changes is fundamental to mitigate and predict future biodiversity changes. Theoretically, species life-history strategies are key determinants shaping the response of populations to environmental impacts. Despite this, the association between species life histories and the response of populations to environmental changes has not been tested. In this study, we analysed the effects of recent land-cover and temperature changes on rates of population change of 1,072 populations recorded in the Living Planet Database. We selected populations with at least 5 yearly consecutive records (after imputation of missing population estimates) between 1992 and 2016, and for which we achieved high population imputation accuracy (in the cases where missing values had to be imputed). These populations were distributed across 553 different locations and included 461 terrestrial amniote vertebrate species (273 birds, 137 mammals, and 51 reptiles) with different life-history strategies. We showed that populations of fast-lived species inhabiting areas that have experienced recent expansion of cropland or bare soil present positive populations trends on average, whereas slow-lived species display negative population trends. Although these findings support previous hypotheses that fast-lived species are better adapted to recover their populations after an environmental perturbation, the sensitivity analysis revealed that model outcomes are strongly influenced by the addition or exclusion of populations with extreme rates of change. Therefore, the results should be interpreted with caution. With climate and land-use changes likely to increase in the future, establishing clear links between species characteristics and responses to these threats is fundamental for designing and conducting conservation actions. The results of this study can aid in evaluating population sensitivity, assessing the likely conservation status of species with poor data coverage, and predicting future scenarios of biodiversity change.

Species-level correlates of land-use responses and climate-change sensitivity in terrestrial vertebrates.

Land-use and climate change are major pressures on terrestrial biodiversity. Species' extinction risk and responses to human pressures relate to ecological traits and other characteristics in some clades. However, large-scale comparative assessments of the associations between traits and responses to multiple human pressures across multiple clades are needed. We investigated whether a set of ecological characteristics that are commonly measured across terrestrial vertebrates (ecological traits and geographic range area) are associated with species' responses to different land-use types and species' likely sensitivity to climate change. We aimed to test whether generalizable patterns in response to these pressures arise across both pressures and across vertebrate clades, which could inform assessments of the global signature of human pressures on vertebrate biodiversity and guide conservation efforts. At the species level, we investigated associations between land-use responses and ecological characteristics with a space-for-time substitution approach, making use of the PREDICTS database. We investigated associations between ecological characteristics and expected climate-change sensitivity, estimated from properties of species realized climatic niches. Among the characteristics we considered, 3 were consistently associated with strong land-use responses and high climate-change sensitivity across terrestrial vertebrate classes: narrow geographic range, narrow habitat breadth, and specialization on natural habitats (which described whether a species occurs in artificial habitats or not). The associations of other traits with species' land-use responses and climate-change sensitivity often depended on species' class and land-use type, highlighting an important degree of context dependency. In all classes, invertebrate eaters and fruit and nectar eaters tended to be negatively affected in disturbed land-use types, whereas invertebrate-eating and plant- and seed-eating birds were estimated to be more sensitive to climate change, raising concerns about the continuation of ecological processes sustained by these species under global changes. Our results highlight a consistently higher sensitivity of narrowly distributed species and habitat specialists to land-use and climate change, which provides support for capturing such characteristics in large-scale vulnerability assessments.

Correlaciones a nivel de especie de las respuestas al uso de suelo y la susceptibilidad al cambio climático en los vertebrados terrestres Resumen El uso de suelo y el cambio climático tienen una presión importante sobre la biodiversidad terrestre. En algunos clados, el riesgo de extinción de las especies y las respuestas a las presiones humanas se relacionan con los rasgos ecológicos y otras características. Sin embargo, varios clados necesitan evaluaciones comparativas a gran escala de las asociaciones entre los rasgos y las respuestas a las presiones humanas. Investigamos si un conjunto de rasgos ecológicos medidos comúnmente en los vertebrados terrestres (rasgos ecológicos y extensión del área geográfica) está asociado con la respuesta de las especies a los diferentes tipos de uso de suelo y la posible susceptibilidad de la especie al cambio climático. Buscamos comprobar si los patrones generalizables de las respuestas a estas presiones surgen en ambas presiones y en todos los clados de vertebrados, lo que podría guiar las evaluaciones de la huella mundial de presiones humanas sobre la diversidad de vertebrados y los esfuerzos de conservación. Investigamos las asociaciones entre la respuesta al uso de suelo y los rasgos ecológicos a nivel de especie con una estrategia de reemplazo de espacio por tiempo y con información de la base de datos PREDICTS. También investigamos las asociaciones entre los rasgos ecológicos y la susceptibilidad al cambio climático esperada, la cual estimamos a partir de las propiedades de los nichos climáticos de las especies. Entre las características que consideramos, tres estuvieron asociadas de manera regular con respuestas fuertes al uso de suelo y alta susceptibilidad al cambio climático en las diferentes clases de vertebrados: la extensión geográfica limitada, la amplitud reducida de hábitat y la especialización en los hábitats naturales (la cual describe si una especie está presente en un hábitat artificial o no). Las asociaciones de otros rasgos con la respuesta de la especie al uso de suelo y su susceptibilidad al cambio climático con frecuencia dependieron de la clase de la especie y el tipo de uso de suelo, lo que resalta un grado importante de dependencia del contexto. En todas las clases, los frugívoros, nectarívoros y los que comen invertebrados eran propensos a sufrir efectos negativos en los usos de suelo de tipo perturbado, mientras que se estimó que las aves herbívoras, las que se alimentan de semillas y las que se alimentan de invertebrados eran más susceptibles al cambio climático, lo que incrementa la preocupación por la continuación de los procesos ecológicos que viven estas especies bajo los cambios globales. Nuestros resultados resaltan una susceptibilidad al uso de suelo y al cambio climático cada vez mayor en las especies con distribución limitada y las especialistas de hábitat, lo que proporciona un respaldo para la captura de dichas características en las evaluaciones a gran escala de la vulnerabilidad.

Intensive human land uses negatively affect vertebrate functional diversity.

Land-use change is the leading driver of global biodiversity loss thus characterising its impacts on the functional structure of ecological communities is an urgent challenge. Using a database describing vertebrate assemblages in different land uses, we assess how the type and intensity of land use affect the functional diversity of vertebrates globally. We find that human land uses alter local functional structure by driving declines in functional diversity, with the strongest effects in the most disturbed land uses (intensely used urban sites, cropland and pastures), and among amphibians and birds. Both tropical and temperate areas experience important functional losses, which are only partially offset by functional gains. Tropical assemblages are more likely to show decreases in functional diversity that exceed those expected from species loss alone. Our results indicate that land-use change non-randomly reshapes the functional structure of vertebrate assemblages, raising concerns about the continuation of ecological processes sustained by vertebrates.

Vertebrate population trends are influenced by interactions between land use, climatic position, habitat loss and climate change.

Rapid human-driven environmental changes are impacting animal populations around the world. Currently, land-use and climate change are two of the biggest pressures facing biodiversity. However, studies investigating the impacts of these pressures on population trends often do not consider potential interactions between climate and land-use change. Further, a population's climatic position (how close the ambient temperature and precipitation conditions are to the species' climatic tolerance limits) is known to influence responses to climate change but has yet to be investigated with regard to its influence on land-use change responses over time. Consequently, important variations across species' ranges in responses to environmental changes may be being overlooked. Here, we combine data from the Living Planet and BioTIME databases to carry out a global analysis exploring the impacts of land use, habitat loss, climatic position, climate change and the interactions between these variables, on vertebrate population trends. By bringing these datasets together, we analyse over 7,000 populations across 42 countries. We find that land-use change is interacting with climate change and a population's climatic position to influence rates of population change. Moreover, features of a population's local landscape (such as surrounding land cover) play important roles in these interactions. For example, populations in agricultural land uses where maximum temperatures were closer to their hot thermal limit, declined at faster rates when there had also been rapid losses in surrounding semi-natural habitat. The complex interactions between these variables on populations highlight the importance of taking intraspecific variation and interactions between local and global pressures into account. Understanding how drivers of change are interacting and impacting populations, and how this varies spatially, is critical if we are to identify populations at risk, predict species' responses to future environmental changes and produce suitable conservation strategies.

Prioritizing conservation in sub-Saharan African lakes based on freshwater biodiversity and algal bloom metrics.

As agricultural land use and climate change continue to pose increasing threats to biodiversity in sub-Saharan Africa, efforts are being made to identify areas where trade-offs between future agricultural development and terrestrial biodiversity conservation are expected to be greatest. However, little research so far has focused on freshwater biodiversity conservation in the context of agricultural development in sub-Saharan Africa. We aimed to identify lakes and lake areas where freshwater biodiversity is most likely to be affected by eutrophication and Harmful Algal Blooms (i.e., when algae multiply to the extent that they have toxic effects on people and freshwater fauna), some of the most important emerging threats to freshwater ecosystems worldwide, especially with the onset of climate change. Using novel remote-sensing techniques, we identified lakes that demonstrated high biodiversity and algal bloom levels. We calculated the richness of freshwater species and the normalized difference chlorophyll index (NDCI) to prioritize lakes in Ghana, Ethiopia, Zambia, and bordering countries, of high priority for conservation. We identified 169 priority lakes and lake areas for conservation, based on high levels of biodiversity exposed to potentially harmful algal blooms. Zambia had the most lakes identified as conservation priorities (76% of its small lakes and five 100-km2 areas in large lakes). Many of the conservation priority lakes and lake areas identified in this study were in transboundary watersheds; thus, collaborative water resource management and conservation at the watershed scale is needed. The use of remote-sensing tools to prioritize freshwater systems for conservation according to algal-bloom risk is vital in remote, undersampled world regions, especially given the increasing threat posed to freshwater biodiversity by rapidly expanding agriculture and climate change.

Priorización de la Conservación en los Lagos Sub-Saharianos con base en Medidas de Biodiversidad de Aguas Dulces y Floración de Algas Resumen Conforme el cambio climático y el uso de suelo para cultivos siguen representando amenazas crecientes para la biodiversidad en la región sub-sahariana de África, se están realizando esfuerzos para identificar las áreas en donde se espera que sucedan las mayores compensaciones entre el desarrollo agrícola venidero y la conservación de la biodiversidad terrestre. Sin embargo, pocas investigaciones se han centrado en la conservación de la biodiversidad de aguas dulces dentro del contexto del desarrollo agrícola en esta región de África. Nos enfocamos en localizar las áreas en donde sea más probable que la biodiversidad de aguas dulces se vea afectada por la eutrofización y las floraciones de algas (es decir, cuando las algas se multiplican a tal grado que tienen efectos tóxicos sobre las personas y la fauna de agua dulce), dos de las amenazas emergentes más importantes para los ecosistemas de agua dulce en todo el mundo debido al cambio climático. Mediante técnicas novedosas de teledetección identificamos los lagos que se traslapaban con áreas de gran biodiversidad y floraciones de algas. Calculamos la riqueza de especies de agua dulce y el índice de diferencia normalizada de clorofila (IDNC) para identificar los lagos de suma importancia para la conservación en Ghana, Etiopía, Zambia y sus países fronterizos. Identificamos 169 áreas prioritarias para la conservación con base en los niveles elevados de biodiversidad expuestos a las floraciones de algas potencialmente dañinas. Zambia tuvo la mayor cantidad de lagos identificados como prioridades de conservación (76% de sus lagos pequeños y cinco áreas de 100 km2 en los grandes lagos). Las amenazas para la biodiversidad de agua dulce estuvieron presentes a nivel de cuenca, con frecuencia con una extensión más allá de las fronteras políticas de un país; por lo tanto, se requiere que el manejo de recursos hídricos y la conservación sean esfuerzos colaborativos a nivel de cuenca. El uso de herramientas de teledetección para priorizar la conservación de los sistemas de agua dulce de acuerdo con el riesgo de floración de algas es vital en las regiones remotas y poco muestreadas del mundo, especialmente debido a la amenaza creciente que representan el cambio climático y la expansión agrícola para la biodiversidad de agua dulce.

Grand challenges in biodiversity-ecosystem functioning research in the era of science-policy platforms require explicit consideration of feedbacks.

Feedbacks are an essential feature of resilient socio-economic systems, yet the feedbacks between biodiversity, ecosystem services and human wellbeing are not fully accounted for in global policy efforts that consider future scenarios for human activities and their consequences for nature. Failure to integrate feedbacks in our knowledge frameworks exacerbates uncertainty in future projections and potentially prevents us from realizing the full benefits of actions we can take to enhance sustainability. We identify six scientific research challenges that, if addressed, could allow future policy, conservation and monitoring efforts to quantitatively account for ecosystem and societal consequences of biodiversity change. Placing feedbacks prominently in our frameworks would lead to (i) coordinated observation of biodiversity change, ecosystem functions and human actions, (ii) joint experiment and observation programmes, (iii) more effective use of emerging technologies in biodiversity science and policy, and (iv) a more inclusive and integrated global community of biodiversity observers. To meet these challenges, we outline a five-point action plan for collaboration and connection among scientists and policymakers that emphasizes diversity, inclusion and open access. Efforts to protect biodiversity require the best possible scientific understanding of human activities, biodiversity trends, ecosystem functions and-critically-the feedbacks among them.

Widespread winners and narrow-ranged losers: Land use homogenizes biodiversity in local assemblages worldwide.

Human use of the land (for agriculture and settlements) has a substantial negative effect on biodiversity globally. However, not all species are adversely affected by land use, and indeed, some benefit from the creation of novel habitat. Geographically rare species may be more negatively affected by land use than widespread species, but data limitations have so far prevented global multi-clade assessments of land-use effects on narrow-ranged and widespread species. We analyse a large, global database to show consistent differences in assemblage composition. Compared with natural habitat, assemblages in disturbed habitats have more widespread species on average, especially in urban areas and the tropics. All else being equal, this result means that human land use is homogenizing assemblage composition across space. Disturbed habitats show both reduced abundances of narrow-ranged species and increased abundances of widespread species. Our results are very important for biodiversity conservation because narrow-ranged species are typically at higher risk of extinction than widespread species. Furthermore, the shift to more widespread species may also affect ecosystem functioning by reducing both the contribution of rare species and the diversity of species' responses to environmental changes among local assemblages.

Global effects of land use on local terrestrial biodiversity.

Human activities, especially conversion and degradation of habitats, are causing global biodiversity declines. How local ecological assemblages are responding is less clear--a concern given their importance for many ecosystem functions and services. We analysed a terrestrial assemblage database of unprecedented geographic and taxonomic coverage to quantify local biodiversity responses to land use and related changes. Here we show that in the worst-affected habitats, these pressures reduce within-sample species richness by an average of 76.5%, total abundance by 39.5% and rarefaction-based richness by 40.3%. We estimate that, globally, these pressures have already slightly reduced average within-sample richness (by 13.6%), total abundance (10.7%) and rarefaction-based richness (8.1%), with changes showing marked spatial variation. Rapid further losses are predicted under a business-as-usual land-use scenario; within-sample richness is projected to fall by a further 3.4% globally by 2100, with losses concentrated in biodiverse but economically poor countries. Strong mitigation can deliver much more positive biodiversity changes (up to a 1.9% average increase) that are less strongly related to countries' socioeconomic status.

Effects of rarity form on species' responses to land use.

Anthropogenic land-use change causes substantial changes in local and global biodiversity. Rare and common species can differ in sensitivity to land-use change; rare species are expected to be affected more negatively. Rarity may be defined in terms of geographic range size, population density, or breadth of habitat requirements. How these 3 forms of rarity interact in determining global responses to land use is yet to be assessed. Using global data representing 912 vertebrate species, we tested for differences in responses to land use of species characterized by different types of rarity. Land-use responses were fitted using generalized linear mixed-effects models, allowing responses to vary among groups of species with different forms of rarity. Species considered rare with respect to all 3 forms of rarity showed particularly strong declines in disturbed land uses (>40% of species and 30% of individuals in the most disturbed land uses). In contrast, species common both geographically and numerically and with broad habitat requirements showed strong increases (up to 90% increase in species and 40% in abundance in some land uses). Our results suggest that efforts to understand the vulnerability of species to environmental changes should account for different types of rarity where possible. Our results also have potentially important implications for ecosystem functioning, given that rare species may play unique roles within ecosystems.

Efectos de la Forma de Rareza sobre las Respuestas de las Especies ante el Uso de Suelo Sykes et al. Resumen Los cambios en el uso de suelo ocasionados por el humano causan modificaciones sustanciales en la biodiversidad local y mundial. Las especies raras y comunes pueden tener diferencias en la sensibilidad ante el cambio en el uso de suelo; generalmente se espera que las especcies raras se vean afectadas de manera más negativa. La rareza puede estar definida en términos del tamaño de la extensión geográfica, la densidad poblacional o la gama de requerimientos de hábitat. La manera en que interactúan estas tres formas de rareza para determinar las respuestas mundiales ante el uso de suelo todavía no ha sido evaluada. Buscamos diferencias en las respuestas ante el uso de suelo en especies caracterizadas por diferentes tipos de rareza. Para esto usamos datos mundiales que representaron a 912 especies de vertebrados. Las respuestas ante el uso de suelo fueron ajustadas con modelos lineales y generalizados de efectos mixtos, lo que permitió que las respuestas variaran entre los grupos de especies con diferentes formas de rareza. Las especies consideradas como raras con respecto a las tres formas de rareza mostraron declinaciones particularmente fuertes en los usos de suelos perturbados (>40% de las especies y 30% de los individuos en los usos de suelo más perturbados). Como contraste, las especies comunes tanto geográfica como numéricamente y con requerimientos amplios de hábitat mostraron incrementos sólidos (hasta un 90% de incremento de las especies y 40% en abundancia para algunos usos de suelo). Nuestros resultados sugieren que los esfuerzos para entender la vulnerabilidad de las especies ante los cambios ambientales deberían considerar los diferentes tipos de rareza cuando sea posible. Nuestros resultados también tienen implicaciones potencialmente importantes para el funcionamiento de los ecosistemas, dado que las especies raras pueden tener un papel único dentro del ecosistema.

Conventional land-use intensification reduces species richness and increases production: A global meta-analysis.

Most current research on land-use intensification addresses its potential to either threaten biodiversity or to boost agricultural production. However, little is known about the simultaneous effects of intensification on biodiversity and yield. To determine the responses of species richness and yield to conventional intensification, we conducted a global meta-analysis synthesizing 115 studies which collected data for both variables at the same locations. We extracted 449 cases that cover a variety of areas used for agricultural (crops, fodder) and silvicultural (wood) production. We found that, across all production systems and species groups, conventional intensification is successful in increasing yield (grand mean + 20.3%), but it also results in a loss of species richness (-8.9%). However, analysis of sub-groups revealed inconsistent results. For example, small intensification steps within low intensity systems did not affect yield or species richness. Within high-intensity systems species losses were non-significant but yield gains were substantial (+15.2%). Conventional intensification within medium intensity systems revealed the highest yield increase (+84.9%) and showed the largest loss in species richness (-22.9%). Production systems differed in their magnitude of richness response, with insignificant changes in silvicultural systems and substantial losses in crop systems (-21.2%). In addition, this meta-analysis identifies a lack of studies that collect robust biodiversity (i.e. beyond species richness) and yield data at the same sites and that provide quantitative information on land-use intensity. Our findings suggest that, in many cases, conventional land-use intensification drives a trade-off between species richness and production. However, species richness losses were often not significantly different from zero, suggesting even conventional intensification can result in yield increases without coming at the expense of biodiversity loss. These results should guide future research to close existing research gaps and to understand the circumstances required to achieve such win-win or win-no-harm situations in conventional agriculture.

Future effects of climate and land-use change on terrestrial vertebrate community diversity under different scenarios.

Land-use and climate change are among the greatest threats facing biodiversity, but understanding their combined effects has been hampered by modelling and data limitations, resulting in part from the very different scales at which land-use and climate processes operate. I combine two different modelling paradigms to predict the separate and combined (additive) effects of climate and land-use change on terrestrial vertebrate communities under four different scenarios. I predict that climate-change effects are likely to become a major pressure on biodiversity in the coming decades, probably matching or exceeding the effects of land-use change by 2070. The combined effects of both pressures are predicted to lead to an average cumulative loss of 37.9% of species from vertebrate communities under 'business as usual' (uncertainty ranging from 15.7% to 54.2%). Areas that are predicted to experience the effects of both pressures are concentrated in tropical grasslands and savannahs. The results have important implications for the conservation of biodiversity in future, and for the ability of biodiversity to support important ecosystem functions, upon which humans rely.

Bird and bat species' global vulnerability to collision mortality at wind farms revealed through a trait-based assessment.

Mitigation of anthropogenic climate change involves deployments of renewable energy worldwide, including wind farms, which can pose a significant collision risk to volant animals. Most studies into the collision risk between species and wind turbines, however, have taken place in industrialized countries. Potential effects for many locations and species therefore remain unclear. To redress this gap, we conducted a systematic literature review of recorded collisions between birds and bats and wind turbines within developed countries. We related collision rate to species-level traits and turbine characteristics to quantify the potential vulnerability of 9538 bird and 888 bat species globally. Avian collision rate was affected by migratory strategy, dispersal distance and habitat associations, and bat collision rates were influenced by dispersal distance. For birds and bats, larger turbine capacity (megawatts) increased collision rates; however, deploying a smaller number of large turbines with greater energy output reduced total collision risk per unit energy output, although bat mortality increased again with the largest turbines. Areas with high concentrations of vulnerable species were also identified, including migration corridors. Our results can therefore guide wind farm design and location to reduce the risk of large-scale animal mortality. This is the first quantitative global assessment of the relative collision vulnerability of species groups with wind turbines, providing valuable guidance for minimizing potentially serious negative impacts on biodiversity.

Emergent global patterns of ecosystem structure and function from a mechanistic general ecosystem model.

Anthropogenic activities are causing widespread degradation of ecosystems worldwide, threatening the ecosystem services upon which all human life depends. Improved understanding of this degradation is urgently needed to improve avoidance and mitigation measures. One tool to assist these efforts is predictive models of ecosystem structure and function that are mechanistic: based on fundamental ecological principles. Here we present the first mechanistic General Ecosystem Model (GEM) of ecosystem structure and function that is both global and applies in all terrestrial and marine environments. Functional forms and parameter values were derived from the theoretical and empirical literature where possible. Simulations of the fate of all organisms with body masses between 10 µg and 150,000 kg (a range of 14 orders of magnitude) across the globe led to emergent properties at individual (e.g., growth rate), community (e.g., biomass turnover rates), ecosystem (e.g., trophic pyramids), and macroecological scales (e.g., global patterns of trophic structure) that are in general agreement with current data and theory. These properties emerged from our encoding of the biology of, and interactions among, individual organisms without any direct constraints on the properties themselves. Our results indicate that ecologists have gathered sufficient information to begin to build realistic, global, and mechanistic models of ecosystems, capable of predicting a diverse range of ecosystem properties and their response to human pressures.

Synergistic impacts of habitat loss and fragmentation on model ecosystems.

Habitat loss and fragmentation are major threats to biodiversity, yet separating their effects is challenging. We use a multi-trophic, trait-based, and spatially explicit general ecosystem model to examine the independent and synergistic effects of these processes on ecosystem structure. We manipulated habitat by removing plant biomass in varying spatial extents, intensities, and configurations. We found that emergent synergistic interactions of loss and fragmentation are major determinants of ecosystem response, including population declines and trophic pyramid shifts. Furthermore, trait-mediated interactions, such as a disproportionate sensitivity of large-sized organisms to fragmentation, produce significant effects in shaping responses. We also show that top-down regulation mitigates the effects of land use on plant biomass loss, suggesting that models lacking these interactions-including most carbon stock models-may not adequately capture land-use change impacts. Our results have important implications for understanding ecosystem responses to environmental change, and assessing the impacts of habitat fragmentation.

Harmonizing Biodiversity Conservation and Productivity in the Context of Increasing Demands on Landscapes.

Biodiversity conservation and agricultural production are often seen as mutually exclusive objectives. Strategies for reconciling them are intensely debated. We argue that harmonization between biodiversity conservation and crop production can be improved by increasing our understanding of the underlying relationships between them. We provide a general conceptual framework that links biodiversity and agricultural production through the separate relationships between land use and biodiversity and between land use and production. Hypothesized relationships are derived by synthesizing existing empirical and theoretical ecological knowledge. The framework suggests nonlinear relationships caused by the multifaceted impacts of land use (composition, configuration, and intensity). We propose solutions for overcoming the apparently dichotomous aims of maximizing either biodiversity conservation or agricultural production and suggest new hypotheses that emerge from our proposed framework.