Matthew G. E. Mitchell

Crop diversification is a promising strategy to strengthen pest control services in agricultural landscapes. Diversifying crops may limit pests through host crop dilution or by enhancing top‐down control by their enemies. However, crop diversification may also benefit generalist pests through higher resource continuity. Using a large‐scale dataset encompassing 742 landscapes across 13 countries, we assessed the impact of landscape‐scale crop diversity on the abundance of natural enemies, the potential for biological control, and insect pest abundance. Crop diversification did not increase the overall abundance of natural enemies or the potential for biological pest control. Instead, crop diversity primarily favoured the abundance of specialist natural enemies and pests in highly simplified landscapes, an effect that was reduced in landscapes with high proportions of semi‐natural habitats. Lastly, low proportions of host crops in the landscape were associated with higher abundances of natural enemies. Taken together, our results indicate that crop diversification is not a ‘one size fits all’ strategy to control agricultural pests, and that other landscape characteristics, such as high amounts of semi‐natural habitats, must be considered to enhance biological pest control services.

Aim Agriculture depends heavily on biodiversity, yet unsustainable management practices continue to affect a wide range of organisms and ecosystems at unprecedented levels worldwide. Addressing the global challenge of biodiversity loss requires access to consolidated knowledge across management practices, spatial levels, and taxonomic groups. Location Global Time period 1994 to 2022 Major taxa studied Animals, microorganisms, plants. Methods We conducted a comprehensive literature review synthesising data from all meta-analyses about the impacts of agricultural management practices on biodiversity in croplands, covering field, farm, and landscape levels. From 200 retained meta-analyses, we extracted 1,885 mean effect sizes (from 69,850 comparisons between a control and treatment) assessing the impact of management practices on biodiversity, alongside characterising over 9,000 primary papers. Results Seven high-income countries, notably the USA, China, and Brazil dominate agricultural impact studies with fertiliser use, phytosanitary interventions and crop diversification receiving widespread attention. The focus on individual practices overshadows research at the farm and landscape level. Taxonomically, Animalia, especially arthropods, are heavily studied while taxa such as annelids and plants receive comparatively less attention. Effect sizes are predominantly calculated from averaged abundance data. Significant gaps persist in terms of studies on the effects of agricultural interventions on specific taxonomic groups (e.g. annelids, mammals) and studies analysing functional traits. Main conclusions Our study highlights the importance of analysing the effects of combined practices to accurately reflect real-world farming contexts. While abundance metrics are common, reflecting several biodiversity facets and adopting a more balanced research approach across taxa are crucial for understanding biodiversity responses to agricultural changes and informing conservation strategies. Given the unbalanced evidence on impacts of agricultural practices on biodiversity, caution is required when utilising meta-analytical findings for informing public policies or integrating them into global assessment models like life-cycle assessments or global flux models.

Pollinators play a crucial role in global crop production, enhancing crop yields, nutritional value and fruit quality. However, their wild populations worldwide have been experiencing alarming declines. We investigated the contribution of wild pollinators to nutrition and farmer income in Canada, while examining the spatial distribution of pollination services. We used publicly available data on crop types, yields, nutrient content, and farm gate values, alongside information on natural habitats. Our findings suggest that wild pollinators in Canada help sustain the equivalent of approximately 24.4 million people each year in terms of nutrition and generate an annual income of nearly CAD$2.8 billion for farmers. To provide context, these estimates exceed half of the Canadian population and correspond to 5% of total national crop-related farm income. However, significant benefit gaps exist due to the lack of nearby pollinator habitat and insufficient pollination of dependent crops at a national scale. Addressing these gaps could potentially provide an additional nutrition supply for nearly 30 million equivalent people and increase farmer income by CAD$3 billion. We discuss how and where efforts focused on preserving and enhancing wild pollinator habitats, promoting sustainable farming practices, and raising awareness among stakeholders are crucial for the long-term viability of wild pollinator populations and the sustainability of agricultural systems in Canada. Our research underscores the urgent need for a national strategy aimed at safeguarding wild pollinators. Implementing such a strategy would not only contribute to strengthening local economies but also ensure the production of nutritionally essential food.

Context: Biodiversity loss is predicted to have significant impacts on ecosystem services based on previous ecological work at small spatial and temporal scales. However, scaling up understanding of biodiversity-ecosystem service (BES) relationships to broader scales is difficult since ecosystem services emerge from complex interactions between ecosystems, people, and technology.Objectives: In order to inform and direct future BES research, identify and categorise the ecological and social-ecological drivers operating at different spatial scales that could strengthen or weaken BES relationships.Methods: We developed a conceptual framework to understand the potential drivers across spatial scales that could affect BES relationships and then categorized these drivers to synthesize the current state of knowledge.Results: Our conceptual framework identifies ecological/supply-side and social-ecological/demand-side drivers, and cross-scale interactions that influence BES relationships at different scales. Different combinations of these drivers in different contexts will lead to a variety of strengths, shape, and directionality in BES relationships across spatial scales.Conclusions: We put forward four predictions about the spatial scales that the effects of biodiversity, ecosystem service management, ecosystem co-production, and abiotic linkages or effects will be most evident on BES relationships and use these to propose future directions to best advance BES research across scales.

Insect pollinators play a crucial role in global crop production, enhancing fruit and seed yield, improving fruit quality, and increasing crop nutritional value. However, wild pollinator populations worldwide have been experiencing alarming declines. This study investigates the contribution of wild pollinators to nutrition and farmers’ income in Canada, while examining the spatial distribution of these services. Using publicly available data on crop types, yields, nutrient content, and farm gate values, alongside information on natural habitats, we estimated the benefits of wild pollinators across national agricultural landscapes. Our findings reveal that these pollinators sustain approximately 24.4 million equivalent people each year in terms of nutrition and generate an annual income of nearly CAD$2.8 billion for farmers. However, significant benefit gaps exist due to the lack of nearby pollinator habitats and insufficient pollination of dependent crops on a national scale. Addressing these gaps could provide an additional nutrition supply for nearly 30 million equivalent people and increase farmer income by CAD$3 billion. We discuss how and where efforts focused on preserving and enhancing wild pollinator habitats, promoting sustainable farming practices, and raising awareness among stakeholders are crucial for the long-term viability of wild pollinator populations and the sustainability of agricultural systems. This research underscores the urgent need for a national strategy aimed at safeguarding wild pollinators. Implementing such a strategy would not only contribute to strengthening local economies in the regions highlighted in our work but also ensure the production of nutritionally essential food.

Urban living limits access to nature yet spending time in nature is crucial for human health and well-being. To overcome this, urban planners and policymakers are actively looking for different ways to conserve and create more urban nature through parks, street trees, and other greening strategies. However, research shows that in most cities, these greening efforts are not equitably distributed, nor are they equal in terms of their quality or benefits they provide. Creating more equitable access to urban nature is a challenge and a priority in the next decade, and so is improving the quality of urban nature and associated benefits for urbanites. To address this challenge and contribute at both practical and conceptual levels, we propose a new Local Restorative Nature (LRN) index for geospatially assessing the “restorative quality” of urban nature that can support mental well-being. To contextualize the LRN index, we map the distribution of restorative nature in relation to social vulnerability in Vancouver, Canada. The novel LRN index provides critical insights showing that many neighborhoods with vulnerable populations in Vancouver have less exposure to restorative nature to support mental health and highlights where to strategically prioritize urban greening investment in areas that need it the most. The LRN index is scalable and can be used by urban planners in other cities and contexts to improve equitable distribution of restorative nature and better support urbanites’ well-being.

As fragmented landscapes become increasingly common around the world, managing the spatial arrangement of landscape elements (i.e., landscape configuration) may help to promote the conservation of biodiversity. However, the relative effects of landscape configuration on different dimensions of biodiversity across species assemblages are largely unknown. Thus, a key challenge consists in understanding when it is necessary to focus on landscape configuration, in addition to landscape composition, to achieve multifunctional landscapes. We tested the effects of landscape composition (the percentage of tree cover and built infrastructure) and landscape configuration (degree of fragmentation) on landscape‐level species richness and different metrics of functional diversity of urban birds. We collected data on different bird guilds (nectarivores/frugivores, insectivores) from Brisbane, Australia. Using structural equation models, we found that landscape structure (landscape composition and configuration) affected functional diversity via two main pathways: (1) through effects of landscape composition, mediated by landscape configuration (indirect effects), and (2) through direct (“independent”) effects of landscape composition and configuration, filtering species with extreme trait values. Our results show that landscape‐level species richness declined with the extent of built infrastructure, but patterns of trait diversity did not necessarily correlate with this variable. Landscape configuration had a stronger mediating effect on some metrics of the functional diversity of insectivores than on the functional diversity of frugivores/nectarivores. In addition, fragmentation increased the effects of built infrastructure for some traits (body size and dispersal capacity), but not for others (habitat plasticity and foraging behavior). These results suggest that differential approaches to managing landscape structure are needed depending on whether the focus is on protecting functional diversity or species richness and what the target guild is. Managing landscape fragmentation in areas with high levels of built infrastructure is important if the objective is to protect insectivore species with uncommon traits, even if it is not possible to preserve high levels of species richness. However, if the target is to enhance both functional diversity and species richness of multiple guilds, the focus should be on improving composition through the reduction of negative effects of built infrastructure, rather than promoting specific landscape configurations in growing cities.

Given the massive and growing environmental impacts of conventional agriculture, humanity needs new methods for growing food that not only meet dietary needs but also provide for multiple ecosystem functions with potential benefits to people and biodiversity. Concepts from ecology and complex adaptive systems suggest that persistent structural heterogeneity and functional diversity are key for supporting biodiversity, ecosystem services, and resilience, but these concepts have not been extensively applied in agriculture, which is still dominated by annual monocropping systems. Perennial agriculture seems to embody these ecological concepts—particularly perennial polycultures that combine a variety of long‐lived woody perennial food crops with continuous ground cover. However, our understanding of the benefits and trade‐offs of such systems compared to conventional agriculture is limited, especially in temperate climates. Here, we provide a systematic and comprehensive study of the ecological attributes of 14 woody perennial polyculture farm fields to conventional annual and hay fields in the U.S. Midwest, one of the most industrialized food‐producing regions in the world. We found that perennial fields had (1) more diverse soil fungal, invertebrate, plant, and bird communities but found no difference in soil bacterial communities; (2) less compacted soil; (3) denser ground cover; (4) more active carbon, organic carbon, and nitrogen and the same available phosphorus in the top layer of soil; and (5) more species of predatory, detritivorous, and herbivorous insects, and approximately fourfold higher abundance of herbivorous insects. Food production from the oldest half of perennial fields was only 14.7% of a regional corn/soy rotation by weight, but increased with the age of the perennial field and had high nutritional diversity. Together, these findings indicate that woody perennial polyculture fields in the U.S. Midwest are characterized by higher biodiversity and ecosystem functions than adjacent conventional fields. Woody perennial polycultures in the temperate north might play a role in the transition of agricultural landscapes toward sustaining both people and nature over the long term.

Biosphere reserves (BR) balance biodiversity protection and sustainable use through different management restrictions in three zones: core areas, buffer zones, and transition areas. Information about the links between zoning and ecosystem services (ES) is lacking, particularly in terms of the relative roles of natural contributions (ecosystem properties and functions) and anthropogenic contributions (human inputs such as technology and infrastructure) in coproducing ES. This study aimed to: (1) analyse how coproduction of four ES (crop production, grazing, timber production, recreation) differs across the three zones of BRs; and (2) understand which predictors (zoning, natural and anthropogenic contributions, other environmental characteristics) best explain ES provision within BRs. To do this, we collected spatial data on 137 terrestrial BRs in the European Union and on 16 indicators of ES coproduction. We used non-parametric pairwise Wilcoxon rank sum tests to calculate differences in indicators between zones. We used model selection and multiple linear regression to identify predictors of ES provision patterns. Anthropogenic contributions showed most differences between zones, with contributions generally increasing from buffer zones to transition areas. Natural contributions did not, on average, differ between zones, however, for recreation and crop production they decreased from buffer zones to transition areas. ES provision differed between zones only for crop production and grazing, which increased from buffer zones to transition areas. Regression analysis showed that natural contributions are the best predictors of ES provision for all four services. Our results indicate that zoning of BRs has implications for ES coproduction.