Greenhouse gas emissions in US beef production can be reduced by up to 30% with the adoption of selected mitigation measures.

Greenhouse gas (GHG) emissions from beef production in the United States are unevenly distributed across the supply chain and production regions, complicating where and how to reduce emissions most effectively. Using spatially explicit life cycle assessment methods, we quantify the baseline GHG emissions and mitigation opportunities of 42 practices spanning the supply chain from crop and livestock production to processing. We find that the potential to reduce GHGs across the beef sector ranges up to 30% (20 million tonnes COe reduced and 58 million tonnes CO sequestered each year relative to the baseline) under ubiquitous adoption assumptions, largely driven by opportunities in the grazing stage.

Inequity in consumption of goods and services adds to racial-ethnic disparities in air pollution exposure.

Fine particulate matter (PM) air pollution exposure is the largest environmental health risk factor in the United States. Here, we link PM exposure to the human activities responsible for PM pollution. We use these results to explore "pollution inequity": the difference between the environmental health damage caused by a racial-ethnic group and the damage that group experiences.

Five financial incentives to revive the Gulf of Mexico dead zone and Mississippi basin soils.

A central challenge in the Mississippi River Basin is how to continue to support profitable agricultural production, provide water supply, flood control, transportation, and other benefits, while reducing the current burden of environmental degradation. Several practices have been shown to reduce nutrient runoff and water pollution, and improve soil fertility, while often yielding profits for farmers. Yet many of these beneficial practices remain underutilized.

Socio-environmental consideration of phosphorus flows in the urban sanitation chain of contrasting cities.

Understanding how cities can transform organic waste into a valuable resource is critical to urban sustainability. The capture and recycling of phosphorus (P), and other essential nutrients, from human excreta is particularly important as an alternative organic fertilizer source for agriculture. However, the complex set of socio-environmental factors influencing urban human excreta management is not yet sufficiently integrated into sustainable P research.

Physical, technical, and economic accessibility of resources and reserves need to be distinguished by grade: Application to the case of phosphorus.

The amount of phosphorus in the total environment is finite, yet recent estimates suggest that more than enough phosphate ore resources exist in the lithosphere to meet future increases in demand during the next century. Still, it remains unclear how the accessibility of this resource stock - which is heterogeneous in terms of grade and location - will change as currently accessible resources are utilized, as extraction and processing technologies develop, and as the relative economic costs vary. This study uses an economic framework, the World Trade Model with Rectangular Choice-of-Technology, to link estimates of known geological resources of various grades with the technically and economically accessible reserves.

Sustainable Sourcing of Global Agricultural Raw Materials: Assessing Gaps in Key Impact and Vulnerability Issues and Indicators.

Understanding how to source agricultural raw materials sustainably is challenging in today's globalized food system given the variety of issues to be considered and the multitude of suggested indicators for representing these issues. Furthermore, stakeholders in the global food system both impact these issues and are themselves vulnerable to these issues, an important duality that is often implied but not explicitly described. The attention given to these issues and conceptual frameworks varies greatly--depending largely on the stakeholder perspective--as does the set of indicators developed to measure them.

Feeding nine billion people sustainably: conserving land and water through shifting diets and changes in technologies.

In the early 21st century the extensive clearing of forestland, fresh water scarcity, and sharp rises in the price of food have become causes for concern. These concerns may be substantially exacerbated over the next few decades by the need to provide improved diets for a growing global population. This study applies an inter-regional input-output model of the world economy, the World Trade Model, for analysis of alternative scenarios about satisfying future food requirements by midcentury.