Abstract: To fulfill the national bioenergy goals of the United States,conversion of marginal lands to intensive biomass crop production and/or application of greater amounts of nutrients to existing cropland could be expected. Such change in agricultural practices could produce unintended environmental consequences such as water quality degradation. Select Best Management Practices (BMPs) are evaluated for water quality mitigation effectiveness as well as for their relative cost-effectiveness, issues that are often ignored in evaluation of biofuels as a sustainable solution for energy demand. The water quality impacts of converting pastureland to intensive biomass production for biofuel, evaluated using the Soil Water Assessment Tool (SWAT), indicate significant increases in erosion and nutrient loadings to water bodies. Hydrologic and economic evaluation of the BMPs indicate their implementation produced effective water pollution mitigation but at substantial costs, accentuating the sustainability issue related to the economics of renewable fuels. U.S. national energy policy designed around achieving energy independence should also consider environmental and economic trade-offs for biofuels to be an economically and environmentally sustainable alternative to fossil fuels.
Abstract: Municipalities often face increasing demand for limited water supplies with few available alternative sources. Under some circumstances, bulk water transport may offer a viable alternative. This case study documents a hypothetical transfer between a water utility district in northern California and urban communities located on the coast of central and southern California. We compare bulk water transport costs to those of constructing a new desalination facility, which is the current plan of many communities for increasing supplies. We find that using water bags to transport fresh water between northern and southern California is in some instances a low-cost alternative to desalination. The choice is constrained, however, by concerns about reliability and, thus, risk. Case-study results demonstrate the challenges of water supply augmentation in water-constrained regions.
Abstract: If resilience theory is to be of practical value for policy makers and resource managers, the theory must be translated into sensible decision-support tools. We present herein a set of resilience attributes, developed to characterize human-managed systems, that helps system stakeholders to make practical use of resilience concepts in tangible applications. In order to build and maintain resilience, these stakeholders must be able to understand what qualities or attributes enhance—or detract from—a system’s resilience. We describe standardized resilience terms that can be incorporated into resource management plans and decision-support tools to derive metrics that help managers assess the current resilience status of their systems, make rational resource allocation decisions, and track progress toward meeting goals. Our intention is to provide an approachable set of terms for both specialists and non-specialists alike to apply to programs that would benefit from a resilience perspective. These resilience terms can facilitate the modeling of resilience behavior within systems, as well as support those lacking access to sophisticated models. Our goal is to enable policy makers and resource managers to put resilience theory to work in the real world.
Abstract: The long-term availability of mineral resources is crucial in underpinning human society, technology, and economic activity, and in managing anthropogenic environmental impacts. This is increasingly true for metals that do not generally form the primary product of mines (“host” metals), such as copper or iron, but are recovered as by-products (or sometimes co-products during the processing of primary ores). For these “companion” metals, it is therefore useful to develop methodologies to estimate the recoverable resource, i.e., the amount that could, if desired, be extracted and put into use over the next several decades. We describe here a methodological approach to estimating the recoverable resources of companion metals in metal ores, using preliminary data for some particular host/companion pairs in Australia as examples.
Abstract: Although community-level seed-saving initiatives have existed in many countries around the world for about 30 years, they have rarely been the subject of systematic scientific enquiry. Based on a combination of a literature review and field research, we present a novel comprehensive conceptual framework that focuses on the multiple functions and services provided by community-based seed-saving efforts, in particular community seed banks. This framework is output oriented and complements an input oriented typology of community seed banks presented in 1997. The framework identifies three core functions: conserving genetic resources; enhancing access to and availability of diverse local crops; and ensuring seed and food sovereignty. The framework can be used for analysis of existing seed-saving initiatives and serve as a guide for the establishment of new community seed banks. In addition, it can inform the development or revision of national policies or strategies to support community seed banks. The framework’s utility is illustrated by three case studies of community seed banks in Bangladesh, Guatemala and Nepal.
Abstract: Rare earths are used in the renewable energy technologies such as wind turbines, batteries, catalysts and electric cars. Current mining, processing and sustainability aspects have been described in this paper. Rare earth availability is undergoing a temporary decline due mainly to quotas being imposed by the Chinese government on export and action taken against illegal mining operations. The reduction in availability coupled with increasing demand has led to increased prices for rare earths. Although the prices have come down recently, this situation is likely to be volatile until material becomes available from new sources or formerly closed mines are reopened. Although the number of identified deposits in the world is close to a thousand, there are only a handful of actual operating mines. Prominent currently operating mines are Bayan Obo in China, Mountain Pass in the US and recently opened Mount Weld in Australia. The major contributor to the total greenhouse gas (GHG) footprint of rare earth processing is hydrochloric acid (ca. 38%), followed by steam use (32%) and electricity (12%). Life cycle based water and energy consumption is significantly higher compared with other metals.