Peer-reviewed publications

Food systems that support healthy diets in sustainable, resilient, just, and equitable ways can engender progress in eradicating poverty and malnutrition; protecting human rights; and restoring natural resources. Food system activities have contributed to great gains for humanity but have also led to significant challenges, including hunger, poor diet quality, inequity, and threats to nature. While it is recognized that food systems are central to multiple global commitments and goals, including the Sustainable Development Goals, current trajectories are not aligned to meet these objectives. As mounting crises further stress food systems, the consequences of inaction are clear. The goal of food system transformation is to generate a future where all people have access to healthy diets, which are produced in sustainable and resilient ways that restore nature and deliver just, equitable livelihoods. A rigorous, science-based monitoring framework can support evidence-based policymaking and the work of those who hold key actors accountable in this transformation process. Monitoring can illustrate current performance, facilitate comparisons across geographies and over time, and track progress. We propose a framework centered around five thematic areas related to (1) diets, nutrition, and health; (2) environment and climate; and (3) livelihoods, poverty, and equity; (4) governance; and (5) resilience and sustainability. We hope to call attention to the need to monitor food systems globally to inform decisions and support accountability for better governance of food systems as part of the transformation process. Transformation is possible in the next decade, but rigorous evidence is needed in the countdown to the 2030 SDG global goals.

Despite increasing recognition of the need for more diverse and equitable representation in the sciences, it is unclear whether measurable progress has been made. Here, we examine trends in authorship in coral reef science from 1,677 articles published over the past 16 years (2003-2018) and find that while representation of authors that are women (from 18% to 33%) and from non-OECD nations (from 4% to 13%) have increased over time, progress is slow in achieving more equitable representation. For example, it would take over two decades at the current rate, for female representation to reach 50%, and even slower for non-OECD countries considering change is happening at a slower pace, and equitable representation would likely be higher given there are more coral reef non-OECD countries. . OECD nations also continue to dominate authorship contributions in coral reef science (89%), in research conducted in both OECD (63%) and non-OECD nations (68%). We identify systemic issues that remain prevalent in coral reef science (i.e. parachute science, gender bias) that likely contribute to observed trends. We provide recommendations to address systemic biases in research to foster a more inclusive global science community. Adoption of these recommendations will lead to more creative, innovative, and impactful scientific approaches urgently needed for coral reefs and contribute to environmental justice efforts.

An extensive set of policies, programmes, technologies and strategies have been implemented in the forest sector. Collectively, these ‘levers’ cover a diverse range of approaches, at a variety of scales and are governed by many different stakeholders. It is important for decision-makers to understand which levers might be most useful in achieving poverty alleviation. This paper seeks to answer the question: which forest management policies, programmes, technologies and strategies have been effective at alleviating poverty? We studied 21 different rights-based, regulatory, market and supply chain, and forest and tree management levers for which we could identify a plausible theory of change of how implementation of that lever might alleviate poverty. For every lever we: define and describe the lever; describe the logic or theory of change by which the lever might plausibly be expected to alleviate poverty; summarize the available evidence showing how the lever has alleviated poverty; and discuss the variables that explain heterogeneity in outcomes. Overall, we found limited evidence of these levers being associated with reducing poverty (i.e. moving people out of poverty). Some of the strongest evidence for poverty reduction came from ecotourism, community forest management, agroforestry and, to a lesser extent, payments for ecosystem services (PES). However, we found substantial, varied and context-dependent evidence of several levers being associated with mitigating poverty (i.e. by improving well-being). A multitude of cases showing positive outcomes for poverty mitigation came from community forest management, forest producer organisations, small and medium forest enterprises, PES, and tree crop contract production. A combination of more rigorous and long-term research designs, along with examinations of the cost-effectiveness of different levers, would go a long way to contributing to the design of effective interventions for poverty alleviation.

Marine protected areas (MPAs) are now well established globally as tools for conservation, for enhancing marine biodiversity, and for promoting sustainable fisheries. That said, which regions are labeled as MPAs varies substantially, from those that full protect marine species and prohibit human extraction to those that permit everything from intensive fishing to mining. This inconsistency can in some cases inhibit both conservation and quantifying the proportion of the marine environment that is truly protected. Grorud-Colvert et al. review the consistency of MPAs and propose a framework by which levels of protection can be evaluated and improved.

To inform efforts at preventing future pandemics, we assessed how socio-demographic attributes correlated with wildlife consumption as COVID-19 (coronavirus disease 2019) first spread across Asia. Self-reported wildlife consumption was most strongly related to COVID-19 awareness; those with greater awareness were 11–24% less likely to buy wildlife products. A hypothetical intervention targeting increased awareness, support for wildlife market closures and reduced medical impacts of COVID-19 could halve future wildlife consumption rates across several countries and demographics.

Nature's contributions to people (NCP) may be both beneficial and detrimental to humans' quality of life. Since our origins, humans have been closely related to wild ungulates, which have traditionally played an outstanding role as a source of food or raw materials. Currently, wild ungulates are declining in some regions, but recovering in others throughout passive rewilding processes. This is reshaping human-ungulate interactions. Thus, adequately understanding the benefits and detriments associated with wild ungulate populations is necessary to promote human-ungulate co-existence. Here, we reviewed 575 articles (2000-2019) on human-wild ungulate interactions to identify key knowledge gaps on NCP associated with wild ungulates. Wild ungulate research was mainly distributed into seven research clusters focussing on: (1) silvicultural damage in Eurasia; (2) herbivory and natural vegetation; (3) conflicts in urban areas of North America; (4) agricultural damage in Mediterranean agro-ecosystems; (5) social research in Africa and Asia; (6) agricultural damage in North America; (7) research in natural American Northwest areas. Research mostly focused on detrimental NCP. However, the number of publications mentioning beneficial contributions increased after the Intergovernmental Science-Policy Platform on Biodiversity and Ecosystem Services conceptual framework was implemented. Human-ungulate interactions' research was biased towards the Global North and Cervidae, Suidae and Bovidae families. Regarding detrimental NCP, most publications referred to production damage (e.g. crops), followed by biodiversity damage, and material damage (e.g. traffic collisions). Regarding beneficial NCP, publications mainly highlighted non-material contributions (e.g. recreational hunting), followed by material NCP and regulating contributions (e.g. habitat creation). The main actions taken to manage wild ungulate populations were lethal control and using deterrents and barriers (e.g. fencing), which effectiveness was rarely assessed. Increasing research and awareness about beneficial NCP and effective management tools may help to improve the conservation of wild ungulates and the ecosystems they inhabit to facilitate people-ungulate co-existence in the Anthropocene.

Globally, shrimp farms occupied an estimated 3.490 million hectares (Mha) of land and operated 2.426 Mha of production ponds in 2018. Extensive shrimp farms used 1.804 Mha of farm area (1.377 Mha of production ponds), but produced 11.4% of global shrimp production. An estimated 1.718 Mha of land was required to produce ingredients for feeds used in semi-intensive and intensive shrimp farming, bringing total land use to 5.160 Mha. Extensive production is located in the intertidal zone and much of this land formerly was or still is in mangrove areas. Expansion of shrimp farms into mangrove areas has slowed. Mangrove areas are inferior sites for shrimp farms, and governments have imposed stricter regulations to protect mangroves. Shrimp farming in mangrove areas is unnecessary to supply the global shrimp demand. Scenarios for increasing global shrimp production without further increase in shrimp farm area are presented. But, if the demand for shrimp continues to increase, it will be impossible to freeze the total land footprint for farmed shrimp, because the land needed for feed presently is roughly equal to the direct land use for shrimp farms. Direct land use for farms can be frozen through greater production pond yields.

We calculate potential loss of free-flowing rivers (FFRs) if proposed hydropower projects are built globally. Over 260,000 km of rivers, including Amazon, Congo, Irrawaddy, and Salween mainstem rivers, would lose free-flowing status if all dams were built. We propose a set of tested and proven solutions to navigate trade-offs associated with river conservation and dam development. These solution pathways are framed within the mitigation hierarchy and include (1) avoidance through either formal river protection or through exploration of alternative development options; (2) minimization of impacts through strategic or system-scale planning or re-regulation of downstream flows; (3) restoration of rivers through dam removal; and (4) mitigation of dam impacts through biodiversity offsets that include restoration and protection of FFRs. A series of examples illustrate how avoiding or reducing impacts on rivers is possible – particularly when implemented at a system scale – and can be achieved while maintaining or expanding benefits for climate resilience, water, food, and energy security.

Land transformation reduces biodiversity and regional sustainability, with land price being an indicator of the opportunity cost to a landowner of resisting land conversion. However, reliable spatially explicit databases of current land prices are generally lacking in developing countries. We used tools from data science to scrape 1,487 georeferenced land prices in southern Kenya from the internet. Prices were higher for land near cities and in areas of high agricultural productivity, but also around the Maasai Mara National Reserve. Predicted land prices ranged from US$662 to US$4,618,805 per acre. Land speculation associated with expanding urbanization increases the opportunity and acquisition costs of maintaining conservation buffer zones, corridors, and dispersal areas. However, high land values are also found adjacent to a world-famous tourist destination. Profit-driven turnover of ownership, subdivision, and transformation of land is occurring at a rapid pace in southern Kenya, to the detriment of savanna biodiversity and the sustainability of the pastoral social–ecological system.

Several studies have estimated global inputs of plastic into the environment, relying on national statistics and modeling approaches. However, these estimates exhibit uncertainty driven by limited primary municipal solid waste management data. We compare mismanaged plastic estimates from three global studies (Jambeck et al. (2015), Lebreton and Andrady (2019), and Borrelle et al. (2020)), finding significant differences. Specifically, 58 countries show at least a 25 percentage point difference in estimated mismanagement rates, 27 countries show at least a 50 percentage point difference, and 9 countries show at least a 75 percentage point difference. Further, several top plastic generators exhibit large discrepancies in mismanagement estimates, including China, Russia, and Indonesia. The limitations of global plastic pollution estimates are well-known in the scientific community, and some variation is expected. However, these discrepancies limit policy design and mitigation. Thus, municipal, national, and international monitoring of plastic management and pollution must be improved.