How poverty is measured impacts who gets classified as impoverished.

We test whether the classification of households into poverty categories is meaningfully influenced by the poverty measurement approach that is employed. These classification techniques are widely used by governments, non-profit organizations, and development agencies for policy design and implementation. Using primary data collected in Ethiopia, Ghana, and Uganda, we find almost no agreement in how four commonly used approaches rank 16,150 households in terms of poverty status. This result holds for each country, for urban and rural households, and across the entire socio-economic distribution. Households' poverty rankings differ by an entire quartile on average. Conclusions about progress toward poverty alleviation goals may depend in large part on how poverty is measured.

Ten facts about land systems for sustainability.

Land use is central to addressing sustainability issues, including biodiversity conservation, climate change, food security, poverty alleviation, and sustainable energy. In this paper, we synthesize knowledge accumulated in land system science, the integrated study of terrestrial social-ecological systems, into 10 hard truths that have strong, general, empirical support. These facts help to explain the challenges of achieving sustainability in land use and thus also point toward solutions. The 10 facts are as follows: 1) Meanings and values of land are socially constructed and contested; 2) land systems exhibit complex behaviors with abrupt, hard-to-predict changes; 3) irreversible changes and path dependence are common features of land systems; 4) some land uses have a small footprint but very large impacts; 5) drivers and impacts of land-use change are globally interconnected and spill over to distant locations; 6) humanity lives on a used planet where all land provides benefits to societies; 7) land-use change usually entails trade-offs between different benefits-"win-wins" are thus rare; 8) land tenure and land-use claims are often unclear, overlapping, and contested; 9) the benefits and burdens from land are unequally distributed; and 10) land users have multiple, sometimes conflicting, ideas of what social and environmental justice entails. The facts have implications for governance, but do not provide fixed answers. Instead they constitute a set of core principles which can guide scientists, policy makers, and practitioners toward meeting sustainability challenges in land use.

Social dimensions of fertility behavior and consumption patterns in the Anthropocene.

We consider two aspects of the human enterprise that profoundly affect the global environment: population and consumption. We show that fertility and consumption behavior harbor a class of externalities that have not been much noted in the literature. Both are driven in part by attitudes and preferences that are not egoistic but socially embedded; that is, each household's decisions are influenced by the decisions made by others. In a famous paper, Garrett Hardin [G. Hardin, Science 162, 1243-1248 (1968)] drew attention to overpopulation and concluded that the solution lay in people "abandoning the freedom to breed." That human attitudes and practices are socially embedded suggests that it is possible for people to reduce their fertility rates and consumption demands without experiencing a loss in wellbeing. We focus on fertility in sub-Saharan Africa and consumption in the rich world and argue that bottom-up social mechanisms rather than top-down government interventions are better placed to bring about those ecologically desirable changes.

The demise of caterpillar fungus in the Himalayan region due to climate change and overharvesting.

Demand for traditional medicine ingredients is causing species declines globally. Due to this trade, Himalayan caterpillar fungus (Ophiocordyceps sinensis) has become one of the world's most valuable biological commodities, providing a crucial source of income for hundreds of thousands of collectors. However, the resulting harvesting boom has generated widespread concern over the sustainability of its collection. We investigate whether caterpillar fungus production is decreasing-and if so, why-across its entire range. To overcome the limitations of sparse quantitative data, we use a multiple evidence base approach that makes use of complementarities between local knowledge and ecological modeling. We find that, according to collectors across four countries, caterpillar fungus production has decreased due to habitat degradation, climate change, and especially overexploitation. Our statistical models corroborate that climate change is contributing to this decline. They indicate that caterpillar fungus is more productive under colder conditions, growing in close proximity to areas likely to have permafrost. With significant warming already underway throughout much of its range, we conclude that caterpillar fungus populations have been negatively affected by a combination of overexploitation and climate change. Our results underscore that harvesting is not the sole threat to economically valuable species, and that a collapse of the caterpillar fungus system under ongoing warming and high collection pressure would have serious implications throughout the Himalayan region.

Companies' contribution to sustainability through global supply chains.

Global supply chains play a critical role in many of the most pressing environmental stresses and social struggles identified by the United Nations' Sustainable Development Goals (SDGs). Responding to calls from the global community, companies are adopting a variety of voluntary practices to improve the environmental and/or social management of their suppliers' activities. We develop a global survey of 449 publicly listed companies in the food, textile, and wood-products sectors with annual reports in English to provide insight into how the private sector contributes to advancing the SDGs via such sustainable-sourcing practices. We find that while 52% of companies use at least one sustainable-sourcing practice, these practices are limited in scope; 71% relates to only one or a few input materials and 60.5% apply to only first-tier suppliers. We also find that sustainable-sourcing practices typically address a small subset of the sustainability challenges laid out by the SDGs, primarily focusing on labor rights and compliance with national laws. Consistent with existing hypotheses, companies that face consumer and civil society pressure are associated with a significantly higher probability of adopting sustainable-sourcing practices. Our findings highlight the opportunities and limitations of corporate sustainable-sourcing practices in addressing the myriad sustainability challenges facing our world today.

Natural American Spirit's pro-environment packaging and perceptions of reduced-harm cigarettes.

Natural American Spirit (NAS) cigarettes feature a pro-environment marketing campaign on the packs. The NAS "Respect for the Earth" campaign is the first example of on-the-pack corporate social responsibility advertising. In a randomized survey design, we tested perceptions of NAS relative to other cigarette brands on harms to self, others, and the environment. Never (n = 421), former (n = 135), and current (n = 358) US adult smokers were recruited for an online survey from January through March 2018. All participants viewed packs of both NAS and Pall Mall. Participants were randomized to view NAS vs. Pall Mall and to pack color (blue, green, or yellow/orange), which was matched between brands. Survey items assessed perceptions of health risk of the cigarette brand to self, others, and the environment and corporate perceptions. Consistently on all measures, NAS cigarettes were rated as less harmful for oneself, others, and the environment relative to Pall Mall (p's < .001). Though Reynolds American owns both brands, participants rated the company behind NAS as more socially responsible than the company behind Pall Mall, F[1, 909] = 110.25, p < .001. The NAS advantage was significant irrespective of smoking status, pack color, and brand order, with findings stronger for current than never smokers. Pro-environmental marketing on NAS cigarette packs contributes to misperceptions that the product is safer for people and the environment than other cigarettes and made by a company that is more socially responsible. Stricter government regulations on the use of pro-environment terms in marketing that imply modified risk are needed.

Impacts of nonstate, market-driven governance on Chilean forests.

Global markets for agricultural products, timber, and minerals are critically important drivers of deforestation. The supply chains driving land use change may also provide opportunities to halt deforestation. Market campaigns, moratoria, and certification schemes have been promoted as powerful tools to achieve conservation goals. Despite their promise, there have been few opportunities to rigorously quantify the ability of these nonstate, market-driven (NSMD) governance regimes to deliver conservation outcomes. This study analyzes the impacts of three NSMD governance systems that sought to end the conversion of natural forests to plantations in Chile at the start of the 21st century. Using a multilevel, panel dataset of land use changes in Chile, we identify the impact of participation within each of the governance regimes by implementing a series of matched difference-in-differences analyses. Taking advantage of the mosaic of different NSMD regimes adopted in Chile, we explore the relative effectiveness of different policies. NSMD governance regimes reduced deforestation on participating properties by 2-23%. The NSMD governance regimes we studied included collaborative and confrontational strategies between environmental and industry stakeholders. We find that the more collaborative governance systems studied achieved better environmental performance than more confrontational approaches. Whereas many government conservation programs have targeted regions with little likelihood of conversion, we demonstrate that NSMD governance has the potential to alter behavior on high-deforestation properties.

Land-use policies and corporate investments in agriculture in the Gran Chaco and Chiquitano.

Growing demand for agricultural commodities is causing the expansion of agricultural frontiers onto native vegetation worldwide. Agribusiness companies linking these frontiers to distant spaces of consumption through global commodity chains increasingly make zero-deforestation pledges. However, production and land conversion are often carried out by less-visible local and regional actors that are mobile and responsive to new agricultural expansion opportunities and legal constraints on land use. With more stringent deforestation regulations in some countries, we ask whether their movements are determined partly by differences in land-use policies, resulting in "deforestation havens." We analyze the determinants of investment decisions by agricultural companies in the Gran Chaco and Chiquitano, a region that has become the new deforestation "hot spot" in South America. We test whether companies seek out less-regulated forest areas for new agricultural investments. Based on interviews with 82 companies totaling 2.5 Mha of properties, we show that, in addition to proximity to current investments and the availability of cheap forestland, lower deforestation regulations attract investments by companies that tend to clear more forest, mostly cattle ranching operations, and that lower enforcement attracts all companies. Avoiding deforestation leakage requires harmonizing deforestation regulations across regions and commodities and promoting sustainable intensification in cattle ranching.

An agenda for assessing and improving conservation impacts of sustainability standards in tropical agriculture.

Sustainability standards and certification serve to differentiate and provide market recognition to goods produced in accordance with social and environmental good practices, typically including practices to protect biodiversity. Such standards have seen rapid growth, including in tropical agricultural commodities such as cocoa, coffee, palm oil, soybeans, and tea. Given the role of sustainability standards in influencing land use in hotspots of biodiversity, deforestation, and agricultural intensification, much could be gained from efforts to evaluate and increase the conservation payoff of these schemes. To this end, we devised a systematic approach for monitoring and evaluating the conservation impacts of agricultural sustainability standards and for using the resulting evidence to improve the effectiveness of such standards over time. The approach is oriented around a set of hypotheses and corresponding research questions about how sustainability standards are predicted to deliver conservation benefits. These questions are addressed through data from multiple sources, including basic common information from certification audits; field monitoring of environmental outcomes at a sample of certified sites; and rigorous impact assessment research based on experimental or quasi-experimental methods. Integration of these sources can generate time-series data that are comparable across sites and regions and provide detailed portraits of the effects of sustainability standards. To implement this approach, we propose new collaborations between the conservation research community and the sustainability standards community to develop common indicators and monitoring protocols, foster data sharing and synthesis, and link research and practice more effectively. As the role of sustainability standards in tropical land-use governance continues to evolve, robust evidence on the factors contributing to effectiveness can help to ensure that such standards are designed and implemented to maximize benefits for biodiversity conservation.

Global land use change, economic globalization, and the looming land scarcity.

A central challenge for sustainability is how to preserve forest ecosystems and the services that they provide us while enhancing food production. This challenge for developing countries confronts the force of economic globalization, which seeks cropland that is shrinking in availability and triggers deforestation. Four mechanisms-the displacement, rebound, cascade, and remittance effects-that are amplified by economic globalization accelerate land conversion. A few developing countries have managed a land use transition over the recent decades that simultaneously increased their forest cover and agricultural production. These countries have relied on various mixes of agricultural intensification, land use zoning, forest protection, increased reliance on imported food and wood products, the creation of off-farm jobs, foreign capital investments, and remittances. Sound policies and innovations can therefore reconcile forest preservation with food production. Globalization can be harnessed to increase land use efficiency rather than leading to uncontrolled land use expansion. To do so, land systems should be understood and modeled as open systems with large flows of goods, people, and capital that connect local land use with global-scale factors.

Forest transitions, trade, and the global displacement of land use.

Reducing tropical deforestation is an international priority, given its impacts on carbon emissions and biodiversity. We examined whether recent forest transitions--a shift from net deforestation to net reforestation--involved a geographic displacement of forest clearing across countries through trade in agricultural and forest products. In most of the seven developing countries that recently experienced a forest transition, displacement of land use abroad accompanied local reforestation. Additional global land-use change embodied in their net wood trade offset 74% of their total reforested area. Because the reforesting countries continued to export more agricultural goods than they imported, this net displacement offset 22% of their total reforested area when both agriculture and forestry sectors are included. However, this net displacement increased to 52% during the last 5 y. These countries thus have contributed to a net global reforestation and/or decrease in the pressure on forests, but this global environmental benefit has been shrinking during recent years. The net decrease in the pressure on forests does not account for differences in their ecological quality. Assessments of the impacts of international policies aimed at reducing global deforestation should integrate international trade in agricultural and forest commodities.

Colombian biodiversity is governed by a rich and diverse policy mix.

We lack an understanding of how diverse policymakers interact to govern biodiversity. Taking Colombia as a focal case, we examined six decades of biodiversity governance (1959-2018). Here we analysed the composition of the policy mix, and how it has evolved over time, how policies differ among lead actors and ecosystems, and whether the policy mix addresses the primary threats to biodiversity. We identified 186 biodiversity-related policies that govern multiple ecosystems, use different instruments and address the main threats to biodiversity (that is, agriculture and aquaculture, and biological resource use). We found policy gaps in the governance of invasive species and wildlife trade. Biodiversity policy integration into some sectoral policies, such as climate change, poverty and pollution, has become more common in the past decade. Our results point to an increased need for effective coordination across sectors and actors, as new ones influence and implement the policy mix.

Forest transition in Vietnam and displacement of deforestation abroad.

In some countries across the globe, tropical forest cover is increasing. The national-scale reforestation of Vietnam since 1992 is assumed to contribute to this recovery. It is achieved, however, by the displacement of forest extraction to other countries on the order of 49 (34-70) M m(3), or approximately 39% of the regrowth of Vietnam's forests from 1987 to 2006. Approximately half of wood imports to Vietnam during this period were illegal. Leakage due to policies restricting forest exploitation and displacement due to growing domestic consumption and exports contributed respectively to an estimated 58% and 42% of total displacement. Exports of wood products from Vietnam also grew rapidly, amounting to 84% of the displacement, which is a remarkable feature of the forest transition in Vietnam. Attribution of the displacement and corresponding forest extraction to Vietnam, the source countries or the final consumers is thus debatable. Sixty-one percent of the regrowth in Vietnam was, thus, not associated with displacement abroad. Policies allocating credits to countries for reducing deforestation and forest degradation should monitor illegal timber trade and take into account the policy-induced leakage of wood extraction to other countries.

Agricultural intensification and changes in cultivated areas, 1970-2005.

Does the intensification of agriculture reduce cultivated areas and, in so doing, spare some lands by concentrating production on other lands? Such sparing is important for many reasons, among them the enhanced abilities of released lands to sequester carbon and provide other environmental services. Difficulties measuring the extent of spared land make it impossible to investigate fully the hypothesized causal chain from agricultural intensification to declines in cultivated areas and then to increases in spared land. We analyze the historical circumstances in which rising yields have been accompanied by declines in cultivated areas, thereby leading to land-sparing. We use national-level United Nations Food and Agricultural Organization data on trends in cropland from 1970-2005, with particular emphasis on the 1990-2005 period, for 10 major crop types. Cropland has increased more slowly than population during this period, but paired increases in yields and declines in cropland occurred infrequently, both globally and nationally. Agricultural intensification was not generally accompanied by decline or stasis in cropland area at a national scale during this time period, except in countries with grain imports and conservation set-aside programs. Future projections of cropland abandonment and ensuing environmental services cannot be assumed without explicit policy intervention.

Adolescents' Health Perceptions of Natural American Spirit's On-the-Pack Eco-Friendly Campaign.

PURPOSE: Natural American Spirit (NAS) cigarettes, which have recently grown in popularity, are marketed as eco-friendly and natural. The present study examined whether NAS's on-the-pack messaging influences adolescents' health perceptions of the brand. METHODS: In a mixed-factor design, adolescent participants (N = 1,003, ages 13-17, 75% female) were randomized to one of the six exposure conditions. All viewed images of an NAS and a Pall Mall (comparison brand) cigarette pack, but differed in pack color (blue, green, or gold/orange) and brand viewed first. Perceptions of pack logos, addictiveness, harms to the smoker, others, and the environment were assessed directly after viewing pack images for each brand. RESULTS: Adolescents who perceived NAS as more pro-environment tended to perceive NAS cigarettes to be less addictive, r = -.19, p < .01. NAS cigarettes also were perceived as less addictive and better for the environment than Pall Mall. Most (90%) participants provided nature-friendly words (e.g., environment, recycle) when asked to describe logos on the NAS packs. In adjusted models, relative to Pall Mall, NAS was perceived as healthier for smokers, healthier for smokers' family and friends, and safer for the environment. Findings did not differ by pack color and ever tobacco use. CONCLUSIONS: Adolescents perceived a health advantage for NAS cigarettes with its on-the-pack, eco-friendly and pro-health marketing. The findings are consistent with prior research with adults. Given the accumulating evidence of consumer misperceptions, eco-friendly messaging on cigarettes is a public health concern that warrants further consideration for regulatory intervention.

Climate predicts geographic and temporal variation in mosquito-borne disease dynamics on two continents.

Climate drives population dynamics through multiple mechanisms, which can lead to seemingly context-dependent effects of climate on natural populations. For climate-sensitive diseases, such as dengue, chikungunya, and Zika, climate appears to have opposing effects in different contexts. Here we show that a model, parameterized with laboratory measured climate-driven mosquito physiology, captures three key epidemic characteristics across ecologically and culturally distinct settings in Ecuador and Kenya: the number, timing, and duration of outbreaks. The model generates a range of disease dynamics consistent with observed Aedes aegypti abundances and laboratory-confirmed arboviral incidence with variable accuracy (28-85% for vectors, 44-88% for incidence). The model predicted vector dynamics better in sites with a smaller proportion of young children in the population, lower mean temperature, and homes with piped water and made of cement. Models with limited calibration that robustly capture climate-virus relationships can help guide intervention efforts and climate change disease projections.

Pathogenic landscapes: interactions between land, people, disease vectors, and their animal hosts.

BACKGROUND: Landscape attributes influence spatial variations in disease risk or incidence. We present a review of the key findings from eight case studies that we conducted in Europe and West Africa on the impact of land changes on emerging or re-emerging vector-borne diseases and/or zoonoses. The case studies concern West Nile virus transmission in Senegal, tick-borne encephalitis incidence in Latvia, sandfly abundance in the French Pyrenees, Rift Valley Fever in the Ferlo (Senegal), West Nile Fever and the risk of malaria re-emergence in the Camargue, and rodent-borne Puumala hantavirus and Lyme borreliosis in Belgium. RESULTS: We identified general principles governing landscape epidemiology in these diverse disease systems and geographic regions. We formulated ten propositions that are related to landscape attributes, spatial patterns and habitat connectivity, pathways of pathogen transmission between vectors and hosts, scale issues, land use and ownership, and human behaviour associated with transmission cycles. CONCLUSIONS: A static view of the "pathogenecity" of landscapes overlays maps of the spatial distribution of vectors and their habitats, animal hosts carrying specific pathogens and their habitat, and susceptible human hosts and their land use. A more dynamic view emphasizing the spatial and temporal interactions between these agents at multiple scales is more appropriate. We also highlight the complementarity of the modelling approaches used in our case studies. Integrated analyses at the landscape scale allows a better understanding of interactions between changes in ecosystems and climate, land use and human behaviour, and the ecology of vectors and animal hosts of infectious agents.

The emergence of land change science for global environmental change and sustainability.

Land change science has emerged as a fundamental component of global environmental change and sustainability research. This interdisciplinary field seeks to understand the dynamics of land cover and land use as a coupled human-environment system to address theory, concepts, models, and applications relevant to environmental and societal problems, including the intersection of the two. The major components and advances in land change are addressed: observation and monitoring; understanding the coupled system-causes, impacts, and consequences; modeling; and synthesis issues. The six articles of the special feature are introduced and situated within these components of study.