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Abstract Growing demands on ocean resources are placing increasing pressures on ocean ecosystems. To assess the current state of knowledge of future human pressures on the ocean, we conducted a literature review of recent and projected trends of 25 anthropogenic pressures, comprising most of the identified human pressures on the global oceans. To better understand gaps in the data, we developed a comprehensive framework of the activities contributing to each pressure. All pressures were allocated to five categories (biological disruption, disturbance and removal, altered ocean chemistry, pollution, and climate pressures). All pressures are expected to worsen in the future under business‐as‐usual scenarios (or similar) based on past trajectories and/or models of future scenarios. Eight of the pressures assessed have not been projected into the future (diseases and pathogens, introduced coastal wildlife predation, disruption to sediment dynamics, wildlife strikes, organic and inorganic chemical pollution, light and noise pollution), likely due to the limited availability of data describing current pressures, the challenges of modeling future pressures, and high levels of uncertainty. We thus recommend they receive priority attention to assess their likely future trajectories, given their potential magnitude of influence. 

Anthropogenic stressors to marine ecosystems from climate change and human activities increase extinction risk of species, disrupt ecosystem integrity, and threaten important ecosystem services. Addressing these stressors requires understanding where and to what extent they are impacting marine biological and functional diversity. We model cumulative risk of human impact upon 21,159 marine animal species by combining information on species-level vulnerability and spatial exposure to a range of anthropogenic stressors. We apply this species-level assessment of human impacts to examine patterns of species-stressor interactions within taxonomic groups. We then spatially map impacts across the global ocean, identifying locations where climate-driven impacts overlap with fishing, shipping, and land-based stressors to help inform conservation needs and opportunities. Comparing species-level modeled impacts to those based on marine habitats that represent important marine ecosystems, we find that even relatively untouched habitats may still be home to species at elevated risk, and that many species-rich coastal regions may be at greater risk than indicated from habitat-based methods alone. Finally, we incorporate a trait-based metric of functional diversity to identify where impacts to functionally unique species might pose greater risk to community structure and ecosystem integrity. These complementary lenses of species, function, and habitat provide a richer understanding of threats to marine biodiversity to help inform efforts to meet conservation targets and ensure sustainability of nature’s contributions to people. 

Abstract The production and consumption of food is one of the main drivers of environmental change globally. Meanwhile, many populations remain malnourished due to insufficient or unhealthy diets. Increasingly, dietary shifts are proposed as a means to address both environmental and health concerns. We have a limited understanding of how dietary shifts could alter where food is produced and consumed and how these changes would affect the distribution of environmental pressures both globally and across different groups of people. Here we combine new food flow data linking producing to consuming country with environmental pressures to estimate how a global shift to each of four diets (Indian, EAT-Lancet, Mediterranean, and mean Food Based Dietary Guidelines (FBDGs)) could affect environmental pressures at the global, country income group, and country level. Globally, cumulative pressures decrease under the Indian, EAT-Lancet, and Mediterranean scenarios and increase under FBDGs. On average, low income countries increase their cumulative consumption and production pressures while high income countries decrease their consumption pressures, and typically decrease their production pressures. Increases in low income countries are likely due to the nutritional inadequacy of current diets and the corresponding increases in consumption quantities with a shift to our diet scenarios. Despite these increases, we believe that three out four of our simulated dietary shifts can be seen as a net benefit by decreasing global pressures while low income countries increase pressures to adequately feed their populations. Additionally, considering principles of fairness applied, some nations are more responsible for causing historical environmental pressures and should shoulder more of the change. To facilitate more equitable shifts in global diets, resources, capacity, and knowledge sharing of sustainable agricultural practices are critical to minimize the increases in pressures that low income countries would incur to adequately feed their populations. 

Biodiversity is ultimately the outcome of millions of years of evolution; however, due to increasing human domination of the Earth, biodiversity in its multiple dimensions is changing rapidly. Here, we present “phylogenetic completeness” (PC) as a concept and method for safeguarding Earth's evolutionary heritage by maintaining all branches of the tree of life. Using data for five major terrestrial clades, we performed a global evaluation of the PC approach and compared the results to an approach in which species are conserved or lost at random. We demonstrate that under PC, for a given number of species extinctions, it is possible to maximize the protection of evolutionary innovations in every clade. The PC approach is flexible, may be used to conduct a phylogenetic audit of biodiversity under different conservation scenarios, complements existing conservation efforts, and is linked to the post‐2020 UN Convention on Biodiversity targets. 

Oceans play critical roles in the lives, economies, cultures, and nutrition of people globally, yet face increasing pressures from human activities that put those benefits at risk. To anticipate the future of the world's ocean, we review the many human activities that impose pressures on marine species and ecosystems, evaluating their impacts on marine life, the degree of scientific uncertainty in those assessments, and the expected trajectory over the next few decades. We highlight that fundamental research should prioritize areas of high potential impact and greater uncertainty about ecosystem vulnerability, such as emerging fisheries, organic chemical pollution, seabed mining, and the interactions of cumulative pressures, and deprioritize research on areas that demonstrate little impact or are well understood, such as plastic pollution and ship strikes to marine fauna. There remains hope for a productive and sustainable future ocean, but the window of opportunity for action is closing. 

Data that influence policy and major investment decisions risk entrenching social and political inequities 

A major challenge in sustainability science is identifying targets that maximize ecosystem benefits to humanity while minimizing the risk of crossing critical system thresholds. One critical threshold is the biomass at which populations become so depleted that their population growth rates become negative—depensation. Here, we evaluate how the value of monitoring information increases as a natural resource spends more time near the critical threshold. This benefit emerges because higher monitoring precision promotes higher yield and a greater capacity to recover from overharvest. We show that precautionary buffers that trigger increased monitoring precision as resource levels decline may offer a way to minimize monitoring costs and maximize profits. In a world of finite resources, improving our understanding of the trade-off between precision in estimates of population status and the costs of mismanagement will benefit stakeholders that shoulder the burden of these economic and social costs.