Abstract: Cellulosic-based biofuels are needed to help meet energy needs and to strengthen rural investment and development in the midwestern United States (US). This analysis identifies 11 categories of indicators to measure progress toward sustainability that should be monitored to determine if ecosystem and social services are being maintained, enhanced, or disrupted by production, harvest, storage, and transport of cellulosic feedstock. The indicator categories are identified using scientific literature, input from two stakeholder meetings, and response information from targeted surveys. Five of the categories focus on environmental concerns (soil quality, water quality and quantity, greenhouse gas emissions, biodiversity, and productivity), and six focus on socioeconomic categories (social well-being, energy security, external trade, profitability, resource conservation, and social acceptability). We hypothesize that by measuring these indicators, it will be feasible to quantify changes in ecosystem and social services related to provisioning (e.g., energy, nutrition and materials), cultural, regulating, and supporting services such as optimum soil water and nutrient balances, remediation of wastes, toxins, or other nuisance compounds, and continuation of physical, biological and chemical conditions. To advance our hypothesis from conceptual to real-world sustainability assessments, the next step will be to work with a team of stakeholders and researchers to implement a Landscape Design Project entitled “Enabling Sustainable Landscape Design for Continual Improvement of Operating Bioenergy Supply Systems.” The desired outcome is to identify a science-based approach so that progress toward sustainability can be assessed and useful management practices can be identified.
landscape design
Defining and measuring sustainability of bioenergy systems are difficult because the systems are complex, the science is in early stages of development, and there is a need to generalize what are inherently contextspecific enterprises. These challenges, and the fact that decisions are being made now, create a need for improved communications among scientists as well as between scientists and decision makers. In order for scientists to provide information that is useful to decision makers, they need to come to an agreement on how to measure and report potential risks and benefits of diverse energy alternatives in a way that allows decision makers to compare options. Scientists also need to develop approaches that contribute information about problems and opportunities relevant to policy and decision making. The need for clear communication is especially important at this time when there is a plethora of scientific papers and reports and it is difficult for the public or decision makers to assess the merits of each analysis. We propose three communication guidelines for scientists whose work can contribute to decision making: (1) relationships between the question and the analytical approach should be clearly defined and make common sense; (2) the information should be presented in a manner that non-scientists can understand; and (3) the implications of methods, assumptions, and limitations should be clear. The scientists’ job is to analyze information to build a better understanding of environmental, cultural, and socioeconomic aspects of the sustainability of energy alternatives. The scientific process requires transparency, debate, review, and collaboration across disciplines and time. This paper serves as an introduction to the papers in the special issue on ‘‘Sustainability of Bioenergy Systems: Cradle to Grave’’ because scientific communication is essential to developing more sustainable energy systems. Together these four papers provide a framework under which the effects of bioenergy can be assessed and compared to other energy alternatives to foster sustainability.
Landscape implications of bioenergy feedstock choices are significant and depend on land-use practices and their environmental impacts. Although land-use changes and carbon emissions associated with bioenergy feedstock production are dynamic and complicated, lignocellulosic feedstocks may offer opportunities that enhance sustainability when compared to other transportation fuel alternatives. For bioenergy sustainability, major drivers and concerns revolve around energy security, food production, land productivity, soil carbon and erosion, greenhouse gas emissions, biodiversity, air quality, and water quantity and quality. The many implications of bioenergy feedstock choices require several indicators at multiple scales to provide a more complete accounting of effects. Ultimately, the long-term sustainability of bioenergy feedstock resources (as well as food supplies) throughout the world depends on land-use practices and landscape dynamics. Land-management decisions often invoke trade-offs among potential environmental effects and social and economic factors as well as future opportunities for resource use. The hypothesis being addressed in this paper is that sustainability of bioenergy feedstock production can be achieved via appropriately designed crop residue and perennial lignocellulosic systems. We find that decision makers need scientific advancements and adequate data that both provide quantitative and qualitative measures of the effects of bioenergy feedstock choices at different spatial and temporal scales and allow fair comparisons among available options for renewable liquid fuels.
The increasing demand for bioenergy crops presents our society with the opportunity to design more sustainable landscapes. We have created a Biomass Location for Optimal Sustainability Model (BLOSM) to test the hypothesis that landscape design of cellulosic bioenergy crop plantings may simultaneously improve water quality (i.e. decrease concentrations of sediment, total phosphorus, and total nitrogen) and increase profits for farmer-producers while achieving a feedstock-production goal. BLOSM was run using six scenarios to identify switchgrass (Panicum virgatum) planting locations that might supply a commercial-scale biorefinery planned for the Lower Little Tennessee (LLT) watershed. Each scenario sought to achieve different sustainability goals: improving water quality through reduced nitrogen, phosphorus, or sediment concentrations; maximizing profit; a balance of these conditions; or a balance of these conditions with the additional constraint of converting no more than 25% of agricultural land. Scenario results were compared to a baseline case of no land-use conversion. BLOSM results indicate that a combined economic and environmental optimization approach can achieve multiple objectives simultaneously when a small proportion (1.3%) of the LLT watershed is planted with perennial switchgrass. The multimetric optimization approach described here can be used as a research tool to consider bioenergy plantings for other feedstocks, sustainability criteria, and regions.