• Energy Research

AbstractNatural hazards are naturally occurring physical events that can impact human welfare both directly and indirectly, via shocks to ecosystems and the services they provide. Animal‐mediated pollination is critical for sustaining agricultural economies and biodiversity, yet stands to lose both from present exposure to natural hazards, and future climate‐driven shifts in their distribution, frequency, and intensity. In contrast to the depth of knowledge available for anthropogenic‐related threats, our understanding of how naturally occurring extreme events impact pollinators and pollination has not yet been synthesized. We performed a systematic review and meta‐analysis to examine the potential impacts of natural hazards on pollinators and pollination in natural and cultivated systems. From a total of 117 studies (74% of which were observational), we found evidence of community and population‐level impacts to plants and pollinators from seven hazard types, including climatological (extreme heat, fire, drought), hydrological (flooding), meteorological (hurricanes), and geophysical (volcanic activity, tsunamis). Plant and pollinator response depended on the type of natural hazard and level of biological organization observed; 19% of cases reported no significant impact, whereas the majority of hazards held consistent negative impacts. However, the effects of fire were mixed, but taxa specific; meta‐analysis revealed that bee abundance and species richness tended to increase in response to fire, differing significantly from the mainly negative response of Lepidoptera. Building from this synthesis, we highlight important future directions for pollination‐focused natural hazard research, including the need to: (a) advance climate change research beyond static “mean‐level” changes by better incorporating “shock” events; (b) identify impacts at higher levels of organization, including ecological networks and co‐evolutionary history; and (c) address the notable gap in crop pollination services research—particularly in developing regions of the world. We conclude by discussing implications for safeguarding pollination services in the face of global climate change.

Regional and global assessments periodically update what we know, and highlight what remains to be known, about the linkages between people and nature that both define and depend upon the state of the environment. To guide research that better informs policy and practice, we systematically synthesize knowledge gaps from recent assessments of four regions of the globe and three key themes by the Intergovernmental Science-Policy Platform for Biodiversity and Ecosystem Services. We assess their relevance to global sustainability goals and trace their evolution relative to those identified in the Millennium Ecosystem Assessment. We found that global sustainability goals cannot be achieved without improved knowledge on feedbacks between social and ecological systems, effectiveness of governance systems and the influence of institutions on the social distribution of ecosystem services. These top research priorities have persisted for the 14 years since the Millennium Ecosystem Assessment. Our analysis also reveals limited understanding of the role of indigenous and local knowledge in sustaining nature’s benefits to people. Our findings contribute to a policy-relevant and solution-oriented agenda for global, long-term social-ecological research.

Abstract Enhancing floral resources is a widely accepted strategy for supporting wild bees and promoting crop pollination. Planning effective enhancements can be informed with pollination service models, but these models should capture the behavioural and spatial dynamics of service‐providing organisms. Model predictions, and hence management recommendations, are likely to be sensitive to these dynamics. We used two established models of pollinator foraging to investigate whether habitat enhancement improves crop visitation; whether this effect is influenced by pollinator foraging distance and landscape pattern; and whether behavioural detail improves model predictions. The more detailed central place foraging model better predicted variation in bee visitation observed between habitat types, because it includes optimized trade‐offs between patch quality and distance. Both models performed well when predicting visitation rates across broader scales. Using real agricultural landscapes and simulating habitat enhancements, we show that additional floral resources can have diverging effects on predicted crop visitation. When only co‐flowering resources were added, optimally foraging bees concentrated in enhancements to the detriment of crop pollination. For both models, adding nesting resources increased crop visitation. Finally, the marginal effect of enhancements was greater in simple landscapes. Synthesis and applications. Model results help to identify the conditions under which habitat enhancements are most likely to increase pollination services in agriculture. Three design principles for pollinator habitat enhancement emerge: (a) enhancing only flowers can diminish services by distracting pollinators away from crops, (b) providing nesting resources is more likely to increase bee populations and crop visitation and (c) the benefit of enhancements will be greatest in landscapes that do not already contain abundant habitat.

Biodiversity offsets are most commonly used to mitigate the adverse impacts of development on biodiversity, but some offsets are now also designed to support ecosystem services (ES) goals. Here, we assemble a global database of biodiversity offsets (n = 70) to show that 41% already take ES into consideration, with the objective of enhancing cultural, regulating, and provisioning services. We found that biodiversity offsets were more likely to consider ES when (1) development projects reported impacts on services, (2) offsets had voluntary biodiversity goals, and (3) conservation organizations were involved. However, offsets that considered ES were similar in design (eg offsetting approach, extent, and location) to offsets focused solely on biodiversity, suggesting that including ES goals may represent an attempt to strengthen community support for development projects, rather than to offset known ES impacts. We also found that 34% of all offsets displaced people and negatively affected livelihoods. Therefore, when biodiversity and ES are linked, current practices may not actually improve outcomes, instead incurring additional costs to communities and companies.

AbstractEcosystem services (ES) are an increasingly popular policy framework for connecting biodiversity with human well-being. These efforts typically assume that biodiversity and ES covary, but the relationship between them remains remarkably unclear. Here we analyse >500 recent papers and show that reported relationships differ among ES, methods of measuring biodiversity and ES, and three different approaches to linking them (spatial correlations, management comparisons and functional experiments). For spatial correlations, biodiversity relates more strongly to measures of ES supply than to resulting human benefits. For management comparisons, biodiversity of ‘service providers’ predicts ES more often than biodiversity of functionally unrelated taxa, but the opposite is true for spatial correlations. Functional experiments occur at smaller spatial scales than management and spatial studies, which show contrasting responses to scale. Our results illuminate the varying dynamics relating biodiversity to ES, and show the importance of matching management efforts to the most relevant scientific evidence.