Concentrating vs. spreading our footprint: how to meet humanity's needs at least cost to nature

Risk-appropriate regulations for gene-editing technologies

This paper explores the scope for the newly emerging technologies, based on gene editing (GE) contributing to addressing the global challenges that we face. These challenges relate to food security, climate change and biodiversity depletion. In particular, it examines the science and evidence behind the most appropriate forms of agricultural production to meet these challenges, the targets set in the Global Biodiversity Framework (GBF) agreed to at the end of 2022 and the possible role of GE technologies in contributing to meeting these targets. It then examines the most risk-appropriate regulatory environment required to best facilitate the adoption of GE technology, drawing on the experiences of the impact of regulatory systems for other innovations used in agricultural and food production systems such as genetically modified organisms (GMOs).

Principles for area-based biodiversity conservation

Recent international agreements have strengthened and expanded commitments to protect and restore native habitats for biodiversity protection ("area-based biodiversity conservation"). Nevertheless, biodiversity conservation is hindered because how such commitments should be implemented has been strongly debated, which can lead to suboptimal habitat protection decisions. We argue that, despite the debates, there are three essential principles for area-based biodiversity conservation. These principles are related to habitat geographic coverage, amount, and connectivity. They emerge from evidence that, while large areas of nature are important and must be protected, conservation or restoration of multiple small habitat patches is also critical for global conservation, particularly in regions with high land use. We contend that the many area-based conservation initiatives expected in the coming decades should follow the principles we identify, regardless of ongoing debates. Considering the importance of biodiversity for maintenance of ecosystem services, we suggest that this would bring widespread societal benefits.

Trade-offs in the externalities of pig production are not inevitable

Farming externalities are believed to co-vary negatively, yet trade-offs have rarely been quantified systematically. Here we present data from UK and Brazilian pig production systems representative of most commercial systems across the world ranging from 'intensive' indoor systems through to extensive free range, Organic and woodland systems to explore co-variation among four major externality costs. We found that no specific farming type was consistently associated with good performance across all domains. Generally, systems with low land use have low greenhouse gas emissions but high antimicrobial use and poor animal welfare, and vice versa. Some individual systems performed well in all domains but were not exclusive to any particular type of farming system. Our findings suggest that trade-offs may be avoidable if mitigation focuses on lowering impacts within system types rather than simply changing types of farming.

Ecological filtering shapes the impacts of agricultural deforestation on biodiversity

The biodiversity impacts of agricultural deforestation vary widely across regions. Previous efforts to explain this variation have focused exclusively on the landscape features and management regimes of agricultural systems, neglecting the potentially critical role of ecological filtering in shaping deforestation tolerance of extant species assemblages at large geographical scales via selection for functional traits. Here we provide a large-scale test of this role using a global database of species abundance ratios between matched agricultural and native forest sites that comprises 71 avian assemblages reported in 44 primary studies, and a companion database of 10 functional traits for all 2,647 species involved. Using meta-analytic, phylogenetic and multivariate methods, we show that beyond agricultural features, filtering by the extent of natural environmental variability and the severity of historical anthropogenic deforestation shapes the varying deforestation impacts across species assemblages. For assemblages under greater environmental variability-proxied by drier and more seasonal climates under a greater disturbance regime-and longer deforestation histories, filtering has attenuated the negative impacts of current deforestation by selecting for functional traits linked to stronger deforestation tolerance. Our study provides a previously largely missing piece of knowledge in understanding and managing the biodiversity consequences of deforestation by agricultural deforestation.

Overcoming the impossibility of age-balanced harvest

In many countries, sustainability targets for managed fisheries are often expressed in terms of a fixed percentage of the carrying capacity. Despite the appeal of such a simple quantitative target, an unintended consequence may be a significant tilting of the proportions of biomass across different ages, from what they would have been under harvest-free conditions. Within the framework of a widely used age-structured model, we propose a novel quantitative definition of "age-balanced harvest" that considers the age-class composition relative to that of the unfished population. We show that achieving a perfectly age-balanced policy is impossible if we harvest any fish whatsoever. However, every non-trivial harvest policy has a special structure that favours the young. To quantify the degree of age-imbalance, we propose a cross-entropy function. We formulate an optimisation problem that aims to attain an "age-balanced steady state", subject to adequate yield. We demonstrate that near balanced harvest policies are achievable by sacrificing a small amount of yield. These findings have important implications for sustainable fisheries management by providing insights into trade-offs and harvest policy recommendations.

Land use diversification may mitigate on-site land use impacts on mammal populations and assemblages

Land use is a major cause of biodiversity decline worldwide. Agricultural and forestry diversification measures, such as the inclusion of natural elements or diversified crop types, may reduce impacts on biodiversity. However, the extent to which such measures may compensate for the negative impacts of land use remains unknown. To fill that gap, we synthesised data from 99 studies that recorded mammal populations or assemblages in natural reference sites and in cropland and forest plantations, with or without diversification measures. We quantified the responses to diversification measures based on individual species abundance, species richness and assemblage intactness as quantified by the mean species abundance indicator. In cropland with natural elements, mammal species abundance and richness were, on average, similar to natural conditions, while in cropland without natural elements they were reduced by 28% and 34%, respectively. We found that mammal species richness was comparable between diversified forest plantations and natural reference sites, and 32% lower in plantations without natural elements. In both cropland and plantations, assemblage intactness was reduced compared with natural reference conditions, but the reduction was smaller if diversification measures were in place. In addition, we found that responses to land use were modified by species traits and environmental context. While habitat specialist populations were reduced in cropland without diversification and in forest plantations, habitat generalists benefited. Furthermore, assemblages were impacted more by land use in tropical regions and landscapes containing a larger share of (semi)natural habitat compared with temperate regions and more converted landscapes. Given that mammal assemblage intactness is reduced also when diversification measures are in place, special attention should be directed to species that suffer from land use impacts. That said, our results suggest potential for reconciling land use and mammal conservation, provided that the diversification measures do not compromise yield.

A sustainable food future

The adverse environmental impacts of food production, the ill-health resulting from excess consumption and malnutrition, and the lack of resilience to the increasing number of threats to food availability show that the global system of food provision is not fit for purpose. Here, the causative flaws in the food system are identified and a framework presented for discovering the best ways to eliminate them. This framework is based upon an integrated view of the food system and the socio-economic systems in which it functions. The framework comprises an eight-point plan to describe the structure and functioning of the food system and to discover the optimum ways to bring about the changes needed to deliver a sustainable food future. The plan includes: priorities for research needed to provide options for change; an inclusive analytical methodology that uses the results of this research and incorporates acquisition, sharing and analysis of data; the need for actions at the local and national levels; and the requirements to overcome the barriers to change through education and international cooperation. The prospects for implementation of the plan and the required changes in the outcomes of the food system are discussed.

Economic factors underlying biodiversity loss

Contemporary economic thinking does not acknowledge that the human economy is embedded in Nature; it instead treats humanity as a customer that draws on Nature. In this paper, we present a grammar for economic reasoning that is not built on that error. The grammar is based on a comparison between our demand for Nature's maintenance and regulating services and her ability to supply them on a sustainable basis. The comparison is then used to show that for measuring economic well-being, national statistical offices should estimate an inclusive measure of their economies' wealth and its distribution, not GDP and its distribution. The concept of 'inclusive wealth' is then used to identify policy instruments that ought to be used to manage such global public goods as the open seas and tropical rainforests. Trade liberalization without heed paid to the fate of local ecosystems from which primary products are drawn and exported by developing countries leads to a transfer of inclusive wealth from there to rich importing countries. Humanity's embeddedness in Nature has far-reaching implications for the way we should view human activities-in households, communities, nations and the world. This article is part of the theme issue 'Detecting and attributing the causes of biodiversity change: needs, gaps and solutions'.

Making protected areas effective for biodiversity, climate and food

The spatial extent of marine and terrestrial protected areas (PAs) was among the most intensely debated issues prior to the decision about the post-2020 Global Biodiversity Framework (GBF) of the Convention on Biological Diversity. Positive impacts of PAs on habitats, species diversity and abundance are well documented. Yet, biodiversity loss continues unabated despite efforts to protect 17% of land and 10% of the oceans by 2020. This casts doubt on whether extending PAs to 30%, the agreed target in the Kunming-Montreal GBF, will indeed achieve meaningful biodiversity benefits. Critically, the focus on area coverage obscures the importance of PA effectiveness and overlooks concerns about the impact of PAs on other sustainability objectives. We propose a simple means of assessing and visualising the complex relationships between PA area coverage and effectiveness and their effects on biodiversity conservation, nature-based climate mitigation and food production. Our analysis illustrates how achieving a 30% PA global target could be beneficial for biodiversity and climate. It also highlights important caveats: (i) achieving lofty area coverage objectives alone will be of little benefit without concomitant improvements in effectiveness, (ii) trade-offs with food production particularly for high levels of coverage and effectiveness are likely and (iii) important differences in terrestrial and marine systems need to be recognized when setting and implementing PA targets. The CBD's call for a significant increase in PA will need to be accompanied by clear PA effectiveness goals to reduce and revert dangerous anthropogenic impacts on socio-ecological systems and biodiversity.

Worldviews, values and perspectives towards the future of the livestock sector

The livestock sector is under increasing pressure to respond to numerous sustainability and health challenges related to the production and consumption of livestock products. However, political and market barriers and conflicting worldviews and values across the environmental, socio-economic and political domains have led to considerable sector inertia, and government inaction. The processes that lead to the formulation of perspectives in this space, and that shape action (or inaction), are currently under-researched. This paper presents results of a mixed methods exploration of the influence of environmental worldviews, values, and demographic factors on perspectives towards the future of the livestock sector. The approach combines survey and interview data derived from a sample of livestock representatives (N = 307). Respondents with higher pro-environmental, ecocentric and relational worldviews and values favour more behaviour-oriented solutions. Those with lower pro-environmental and higher techno-centric worldviews and values favour technological solutions to improve the efficiency of production and to enable continued patterns of meat consumption. Demographic variation and qualitative data emphasise the need to recognise cultural and geographic nuance in narratives. This study improves our understanding of the processes that lead to the formulation of perspectives, enabling the development of more holistic solutions that acknowledge all voices in an increasingly polarised debate. Adopting more pluralistic, relational methodologies will therefore be paramount in developing solutions for sustainable livestock futures.

Sharing land via keystone structure: Retaining naturally regenerated trees may efficiently benefit birds in plantations

Meeting food/wood demands with increasing human population and per-capita consumption is a pressing conservation issue, and is often framed as a choice between land sparing and land sharing. Although most empirical studies comparing the efficacy of land sparing and sharing supported land sparing, land sharing may be more efficient if its performance is tested by rigorous experimental design and habitat structures providing crucial resources for various species-keystone structures-are clearly involved. We launched a manipulative experiment to retain naturally regenerated broad-leaved trees when harvesting conifer plantations in central Hokkaido, northern Japan. We surveyed birds in harvested treatments, unharvested plantation controls, and natural forest references 1-year before the harvest and for three consecutive postharvest years. We developed a hierarchical community model separating abundance and space use (territorial proportion overlapping treatment plots) subject to imperfect detection to assess population consequences of retention harvesting. Application of the model to our data showed that retaining some broad-leaved trees increased the total abundance of forest birds over the harvest rotation cycle. Specifically, a preharvest survey showed that the amount of broad-leaved trees increased forest bird abundance in a concave manner (i.e., in the form of diminishing returns). After harvesting, a small amount of retained broad-leaved trees mitigated negative harvesting impacts on abundance, although retention harvesting reduced the space use. Nevertheless, positive retention effects on the postharvest bird density as the product of abundance and space use exhibited a concave form. Thus, small profit reductions were shown to yield large increases in forest bird abundance. The difference in bird abundance between clearcutting and low amounts of broad-leaved tree retention increased slightly from the first to second postharvesting years. We conclude that retaining a small amount of broad-leaved trees may be a cost-effective on-site conservation approach for the management of conifer plantations. The retention of 20-30 broad-leaved trees per ha may be sufficient to maintain higher forest bird abundance than clearcutting over the rotation cycle. Retention approaches can be incorporated into management systems using certification schemes and best management practices. Developing an awareness of the roles and values of naturally regenerated trees is needed to diversify plantations.

Identifying ways of producing pigs more sustainably: tradeoffs and co-benefits in land and antimicrobial use

Pork accounts for the largest proportion of meat consumed globally and demand is growing rapidly. Two important externalities of pig farming are land use and antimicrobial resistance (AMR) driven by antimicrobial use (AMU). Land use and AMU are commonly perceived to be negatively related across different production systems, so those with smaller land footprints pose greater risk to human health. However, the relationship between land use and AMU has never been systematically evaluated. We addressed this by measuring both outcomes for 74 highly diverse pig production systems. We found weak evidence of an AMU/land use tradeoff. We also found several systems characterized by low externality costs in both domains. These potentially promising systems were spread across different label and husbandry types and indeed no type was a reliable indicator of low-cost systems in both externalities. Our findings highlight the importance of using empirical evidence in decision-making, rather than relying on assumptions.

Integrating nature conservation measures in european forest management - An exploratory study of barriers and drivers in 9 european countries

Integrative forest management approaches, aiming to combine the provision of multiple forest ecosystem services in the same forest area, are popular forest management concepts in Europe. Their understanding and application varies, however, across the continent. This paper looks at one dimension of integrative forest management approaches in particular - the integration of nature conservation measures into forest management; focusing on its understanding and application, as well as current and future social, technological, ecological, economic and political factors enabling or hampering this integration. Drawing on 42 qualitative in-depth interviews with national experts and forest practitioners, our study provides insights into the integration of nature conservation measures into forest management systems aimed at wood production and the provision of other forest ecosystem services under various conditions. Across the investigated countries, the main factors perceived to facilitate this integration are the personal motivations and knowledge of forest managers and their long-term economic thinking related to the resilience of the forest in the face of climate and societal change. In turn, the main factors perceived as hampering the integration are current wood-market demands, and a lack of (public) financial incentives. Public pressure is also perceived as an important influencing factor, which can both impede or support integration. Other ambiguous factors include societal knowledge and related knowledge gaps, relationships between local stakeholders, and the legal framework in which forest management operates. The study concludes with suggestions of how to enhance the uptake of the integration of nature conservation measures into forest management in Europe.

Sustainable production of healthy, affordable food in the UK: The pros and cons of plasticulture

An evolving green agenda as the UK seeks to achieve 'net zero' in greenhouse gas emissions by 2050, coupled with our new trading relationship with the European Union, is resulting in new government policies, which will be disruptive to Britain's traditional food and farming practices. These policies encourage sustainable farming and land-sparing to restore natural habitats and will provide an opportunity to address issues such as high emissions of GHGs and dwindling biodiversity resulting from many intensive agricultural practices. To address these and other food challenges such as global conflicts and health issues, Britain will need a revolution in its food system. The aim of this paper is to make the case for such a food revolution where additional healthy food for the UK population is produced in-country in specialised production units for fruits and vegetables developed on sites previously considered unsuitable for crop production. High crop productivity can be achieved in low-cost controlled environments, making extensive use of novel crop science and modern controlled-environment technology. Such systems must be operated with very limited environmental impact. In recent years, growth in the application of plasticulture in UK horticulture has driven some increases in crop yield, quality and value. However, the environmental cost of plastic production and plastic pollution is regarded as a generational challenge that faces the earth system complex. The distribution of plastic waste is ubiquitous, with a significant pollution load arising from a range of agricultural practices. The primary receptor of agriplastic pollution is agricultural soil. Impacts of microplastics on crop productivity and quality and also on human health are only now being investigated. This paper explores the possibility that we can mitigate the adverse environmental effects of agriplastics and thereby exploit the potential of plasticulture to enhance the productivity and positive health impact of UK horticulture.

A systematic review of the definitions and interpretations in scientific literature of 'less but better' meat in high-income settings

'Less but better' is a pragmatic approach to tackling the sustainability challenges of meat consumption and production. Definitions of 'less' and 'better' lack clarity. Here we explore interpretations of these concepts, finding increasing use of 'less but better' in the literature from Western, high-income settings. Despite discrepancies among interpretations of 'less' meat, existing quantifications indicate that significant reduction is needed to achieve desirable food system outcomes. Interpretations of 'better' meat incorporate the delivery of environmental sustainability, improved animal welfare and better health or nutrition, but lack clear principles and omit many sustainability themes. Practices and outcomes are seldom linked, and diverging narratives on interactions between 'less' and 'better' exist. A shared vision of livestock systems with improved sustainability across multiple indicators is needed to establish principles for 'less but better' in order for decision-making to deliver desired outcomes.

Understanding the relative risks of zoonosis emergence under contrasting approaches to meeting livestock product demand

It has been argued that intensive livestock farming increases the risk of pandemics of zoonotic origin because of long-distance livestock movements, high livestock densities, poor animal health and welfare, low disease resistance and low genetic diversity. However, data on many of these factors are limited, and analyses to date typically ignore how land use affects emerging infectious disease (EID) risks, and how these risks might vary across systems with different yields (production per unit area). Extensive, lower yielding practices typically involve larger livestock populations, poorer biosecurity, more workers and more area under farming, resulting in different, but not necessarily lower, EID risks than higher yielding systems producing the same amount of food. To move this discussion forward, we review the evidence for each of the factors that potentially link livestock production practices to EID risk. We explore how each factor might vary with yield and consider how overall risks might differ across a mix of production systems chosen to reflect in broad terms the current livestock sector at a global level and in hypothetical low- and high-yield systems matched by overall level of production. We identify significant knowledge gaps for all potential risk factors and argue these shortfalls in understanding mean we cannot currently determine whether lower or higher yielding systems would better limit the risk of future pandemics.

Extension services can promote pasture restoration: Evidence from Brazil's low carbon agriculture plan

Livestock supply chains account for 14.5% of global greenhouse gases (GHG) emissions. There is a consensus that approaches that improve cattle productivity while enhancing carbon sequestration can contribute to the multiple goals of improving ranchers’ livelihoods and mitigating climate change. Identifying policies that simultaneously increase productivity and sequestration is therefore critical to promote sustainable growth in the livestock sector. This paper documents the impact of training and technical assistance on pasture restoration and productivity in Brazil. We found that providing technical assistance to previously trained producers promoted pasture restoration, induced farmers to use more inputs, helped them improve their practices, and increased productivity and carbon sequestration. These findings highlight the importance of providing customized information to ranchers to help them sustainably intensify.

Innovation and improved practices in the livestock sector represent key opportunities to meet global climate goals. This paper provides evidence that extension services can promote pasture restoration in cattle ranching in Brazil. We use a randomized controlled trial implemented in the context of the ABC Cerrado (a large-scale program launched in 2014 aimed at fostering technology adoption through a combination of training and technical assistance) to examine the effects of different types of extension on agricultural practices, input use, and productivity. Providing technical assistance to previously trained producers promoted pasture restoration, induced farmers to use inputs more intensively, helped them to improve their management and soil conservation practices, and substantially increased revenues. A cost–benefit calculation indicates that US$1 invested in the ABC Cerrado program increased profits by US$1.08 to $1.45. Incorporating carbon savings amplifies this return considerably.