Peer-reviewed publications

Conversion of temperate grasslands in the North American Great Plains has long been identified as a threat to native species and systems. Avoiding conversion, particularly to agricultural cover, has been modeled to show benefits for preserving species diversity and connectivity and maintaining ecosystem services provided by grasslands such as avoiding nutrient and sediment runoff. To identify areas of likely conversion, we employed a probabilistic ecoregion-wide model using soil, topography, and climate variables to simulate future conversion. Our results indicated that roughly 60% of the ecoregion is at moderate or higher risk of conversion or has previously been converted. These data can be used to direct grassland conservation efforts and as a metric to assess suitability of future crop expansion. Also, with added information on government subsidies, clean energy mandates, conservation incentives, and other economic data, our model can be used to assess the benefits and disadvantages of such programs and policies.

Selective logging causes at least half of the emissions from tropical forest degradation. Reduced-impact logging for climate (RIL-C) is proposed as a way to maintain timber production while minimizing forest damage. Here we synthesize data from 61 coordinated field-based surveys of logging impacts in seven countries across the tropics. We estimate that tropical selective logging emitted 834 Tg CO2 in 2015, 6% of total tropical greenhouse gas emissions. Felling, hauling, and skidding caused 59%, 31%, and 10% of these emissions, respectively. We suggest that RIL-C incentive programs consider a feasible target carbon impact factor of 2.3 Mg emitted per Mg of timber extracted. Operational modifications are needed to achieve this target, such as reduced wood waste, narrower haul roads, and lower impact skidding equipment. Full implementation would reduce logging emissions by 44% (366 Tg CO2 year-1) and deliver 4% of the nationally determined contributions to the Paris Climate Agreement from tropical countries, while maintaining timber supplies.

Calls for coral reef restoration are increasing amidst continued declines, yet we know little about long-term outcomes and conditions that lead to successful coral recovery. Here, we report on one of the longest monitoring studies following 16 years of large-scale, "low-tech" experimental reef rehabilitation on rubble fields created by chronic blast fishing in Komodo National Park, Indonesia. After blast fishing had stopped, in the absence of rehabilitation, hard coral cover in rubble fields remained about 3% from 1999 to 2016, but on rehabilitation treatments, cover increased from 0% in 2002 to 44.5% (± 21.9% SD) in 2016. Coral cover varied among sites and treatments (ranging from <5 to &rt80% in 2016) in patterns that may reflect current strength and turbidity. Our results demonstrate that low-tech substrate stabilization can facilitate natural coral recruitment and growth. We conclude that relatively low-cost methods can deliver sustained rehabilitation of hard coral cover and that long-term monitoring should be incorporated more widely in restoration activities to inform return on investment.

The signing of the Paris climate agreement and sustainable development goals demonstrated an international commitment to halting climate change, increasing energy access, and maintaining biodiversity. Successful implementation requires rapidly expanding renewable energy development, which has a large land footprint and can conflict with maintaining natural lands. To quantify the potential to mediate this land conflict, we converted emission reduction commitments submitted as part of the Paris agreement into actionable energy targets, and assessed whether they can be met by developing renewables on converted lands and waters of lower biodiversity and carbon value. The world has 19 times the required energy targets on converted lands, and most countries, including the top ten emitters, can meet the Paris agreement goals. Furthermore, regions (e.g. Africa) that will experience substantial population growth and that currently have limited energy infrastructure can meet their Paris agreement and future energy targets by developing renewable energy on already converted lands. Guiding renewable energy development to converted lands presents opportunities for sustainable development, but also requires incentives and proactive planning to ensure expansion does not exacerbate other environmental challenges.

Projected climate and environmental change are expected to increase the pressure on global freshwater resources. To prepare for and cope with the related risks, stakeholders need to devise plans for sustainable management of river systems, which in turn require the identification of management-appropriate operational units, such as groups of rivers that share similar environmental and biological characteristics. Ideally, these units are of manageable size and biotically or abiotically distinguishable across a variety of river types. Here, we aim to address this need by presenting a new global river classification framework (GloRiC) to establish a common vocabulary and standardized approach to the development of globally comprehensive and integrated river classifications that can be tailored to different goals and requirements.

Voluntary sustainability standards (VSS) are stakeholder-derived principles with measurable and enforceable criteria to promote sustainable production outcomes. While institutional commitments to use VSS to meet sustainable procurement policies have grown rapidly over the past decade, we still have relatively little understanding of the (i) direct environmental benefits of large-scale VSS adoption; (ii) potential perverse indirect impacts of adoption; and (iii) implementation pathways. Here, we illustrate and address these knowledge gaps using an ecosystem service modeling and scenario analysis of Bonsucro, the leading VSS for sugarcane. We find that global compliance with the Bonsucro environmental standards would reduce current sugarcane production area (-24%), net tonnage (-11%), irrigation water use (-65%), nutrient loading (-34%), and greenhouse gas emissions from cultivation (-51%). Under a scenario of doubled global sugarcane production, Bonsucro adoption would further limit water use and greenhouse gas emissions by preventing sugarcane expansion into water-stressed and high-carbon stock ecosystems. This outcome was achieved via expansion largely on existing agricultural lands. However, displacement of other crops could drive detrimental impacts from indirect land use. We find that over half of the potential direct environmental benefits of Bonsucro standards under the doubling scenario could be achieved by targeting adoption in just 10% of global sugarcane production areas. However, designing policy that generates the most environmentally beneficial Bonsucro adoption pathway requires a better understanding of the economic and social costs of VSS adoption. Finally, we suggest research directions to advance sustainable consumption and production.

This study provides evidence that a heliophilic butterfly, the Glanville fritillary (Melitaea cinxia) has adapted differently to environmental variation across latitudes and elevations. 2. In cool air, basking M. cinxia orient themselves perpendicular to the sun's rays to gain heat and take off. During flight, solar heating is reduced because orientation perpendicular to the sun is no longer possible and convective cooling occurs. Consequently, M. cinxia have been shown to suffer net heat loss in flight, even in full sunshine. When flight duration is restricted in this way, the takeoff temperature becomes an important thermal adaptation. 3. Using a thermal imaging camera, takeoff temperatures were measured in experimental butterflies. Butterflies from the northern range limit in Finland took flight at slightly hotter temperatures than butterflies from the southern limit in Spain, and much hotter than butterflies from the elevational limit (1900-2300 m) in the French Alps. Butterflies from low-elevation populations in southern France also took off much hotter than did the nearby Alpine population. 4. These results suggest that the influence of elevation is different from that of latitude in more respects than ambient temperature. Values of solar irradiance in the butterflies' flight season in each region show that insects from the coolest habitats, Finland and the Alps, experienced similar solar irradiance during basking, but that Finns experienced much lower irradiance in flight. This difference may have favored Finnish butterflies evolving higher takeoff temperatures than Alpine butterflies that also flew in cool air but benefited from more intense radiant energy after takeoff.

Food systems have the potential to nurture human health and support environmental sustainability; however, they are currently threatening both. Providing a growing global population with healthy diets from sustainable food systems is an immediate challenge. Although global food production of calories has kept pace with population growth, more than 820 million people have insufficient food and many more consume low-quality diets that cause micronutrient deficiencies and contribute to a substantial rise in the incidence of diet-related obesity and diet-related non-communicable diseases, including coronary heart disease, stroke, and diabetes. Unhealthy diets pose a greater risk to morbidity and mortality than does unsafe sex, and alcohol, drug, and tobacco use combined. Because much of the world's population is inadequately nourished and many environmental systems and processes are pushed beyond safe boundaries by food production, a global transformation of the food system is urgently needed.

Policymakers and investors have perceived securing soil organic carbon as too difficult, with uncertain returns. But new technical, policy and financial opportunities offer hope for rapid progress. Growing visibility and international frameworks for soil organic carbon are not yet matched by investment and action at scale. Soils, mostly privately owned but delivering public goods, are managed under a miscellany of governance arrangements, from local to global1. While there have been compelling calls for action on soils, diverse protagonists across business1,2, governments and civil society who seek to secure soil organic carbon recognize barriers beyond their individual reach—and hence an urgent need for a cross-sectoral global agenda.

The forest landscapes of the Greater Mekong Subregion (GMS) are changing dramatically, with a multitude of impacts from local to global levels. These changes invariably have their foundations in forest governance. The aim of this paper is to assess perceptions of key stakeholders regarding the state of forest governance in the countries of the GMS. The work is based on a quantitative and qualitative analysis of the perceptions of forest governance in the five GMS countries, involving 762 representatives from government, civil society, news media, and rural communities. The work identified many challenges to good forest governance in the countries in the region, as well as noting reasons for optimism. Generally speaking, there was a feeling that the policies, legislation, and institutional frameworks were supportive, but there are numerous challenges in terms of implementation, enforcement, and compliance. The work also presents a program of activities recommended by the research participants to address governance challenges and opportunities in the GMS countries. These include the development of a forest governance monitoring system, and initiatives that support informed decision-making by forest product consumers in the region as well as the implementation of a capacity development program for non-state actors (e.g., civil society, news media) to ensure they are more able to support the diverse, and often demanding, forest governance initiatives.