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Abstract An air-drying process was designed to avoid material decomposition and eliminate the high cost involved in other drying and storage methods. This process, which involved no chipping of biomass at the harvest site, was tested at two study sites in Escanaba, Upper Peninsula, Michigan, from June to November 2011. The primary objective of this study was to evaluate the effect of air-drying on biomass moisture content (MC) and higher heating value (HHV) over field storage. In addition the impacts of different positions within a pile, biomass pile sizes, and weather conditions on biomass moisture change were also tested. Results showed that biomass MCs were significantly reduced during the 5-month field storage period. In addition, the biomass MCs at different positions within a biomass pile were found to be statistically uniform. Results further suggested that making a biomass pile smaller is an appropriate way to store woody biomass when it is scheduled for short-term use, while larger piles should be considered as an option for long-term storage. Biomass HHVs were found to be stable during the 5-month storage period. These results indicate that field piling of unprocessed biomass is a reliable solution for year-round biomass supply without incurring additional costs. Regression analysis also showed that field-stored biomass MC can be significantly impacted by air humidity, while the effect of air temperature and cumulative precipitation on biomass MC was minor.

Contamination of surface waters with microbial pollutants from fecal sources is a significant human health issue. Identification of relative fecal inputs from the mosaic of potential sources common in rural watersheds is essential to effectively develop and deploy mitigation strategies. We conducted a cross-sectional longitudinal survey of fecal indicator bacteria (FIB) concentrations associated with extensive livestock grazing, recreation, and rural residences in three rural, mountainous watersheds in California, USA during critical summer flow conditions. Overall, we found that 86% to 87% of 77 stream sample sites across the study area were below contemporary Escherichia coli-based microbial water quality standards. FIB concentrations were lowest at recreation sites, followed closely by extensive livestock grazing sites. Elevated concentrations and exceedance of water quality standards were highest at sites associated with rural residences, and at intermittently flowing stream sites. Compared to national and state recommended E. coli-based water quality standards, antiquated rural regional policies based on fecal coliform concentrations overestimated potential fecal contamination by as much as four orders of magnitude in this landscape, hindering the identification of the most likely fecal sources and thus the efficient targeting of mitigation practices to address them.

Abstract Compared to firewood, charcoal is a relatively clean and convenient fuel. Nevertheless, the mass production of charcoal can contribute substantially to deforestation, rendering it imperative to regulate charcoal use. This article uses nationally representative panel data on Tanzania conducted in 2008 and 2010 to examine how charcoal expenditures change over time within any given household. The focus of the analysis will be on identifying certain socio-economic factors that affect charcoal use at the household level. The framing of the analysis on variation in time within each household addresses the omitted variable bias that often undermines inference from comparisons across different households. We find that while charcoal expenditures increase with household income, the rise in charcoal use with income is relatively gradual. Household size is unrelated to charcoal expenditures, but urban–rural differences in fuel choice are large even though we include household fixed effects in all specifications. In this regard, policymakers and urban planners need to pay particular attention to the role of urbanization in predicting trends in charcoal expenditures in developing countries like Tanzania.

International agricultural carbon market projects face significant challenges in delivering greenhouse gas mitigation objectives whilst also seeking to provide additional benefits for poverty alleviation. The carbon credit producer (the smallholder farmer) and carbon credit buyer in the carbon market transaction typically operate at different spatial and temporal scales. Buyers operate at a global scale, responding to opportunities for financial speculation and both private and public climate actionplans. Farmers operate within households, farms, and immediate agricultural landscapes, pursuing livelihood and food security needs. These different scales often result in mismatches of timing, payment, and knowledge in market transactions and can be partially rectified by project developers who serve to broker the relationship between the farmers and the buyers. We examined eight East African agricultural carbon market projects to determine how project developers function as bridging organizations and minimize the mismatches between these actors. Results show that projects better bridged the timing and payment gap between buyers and producers when project developers provided non-monetary benefits or direct monetary assistance to farmers. However, knowledge gaps remained a significant barrier for farmers wishing to participate in the market. We discuss how project developers brokered relationships in ways that reflected their interests and highlight the limitations, trade-offs, and challenges that must be overcome if win-win outcomes of poverty alleviation and climate change mitigation are to be realized.

AbstractExtreme weather events have become a dominant feature of the narrative surrounding changes in global climate with large impacts on ecosystem stability, functioning and resilience; however, understanding of their risk of co‐occurrence at the regional scale is lacking. Based on the UK Met Office’s long‐term temperature and rainfall records, we present the first evidence demonstrating significant increases in the magnitude, direction of change and spatial co‐localisation of extreme weather events since 1961. Combining this new understanding with land‐use data sets allowed us to assess the likely consequences on future agricultural production and conservation priority areas. All land‐uses are impacted by the increasing risk of at least one extreme event and conservation areas were identified as the hotspots of risk for the co‐occurrence of multiple event types. Our findings provide a basis to regionally guide land‐use optimisation, land management practices and regulatory actions preserving ecosystem services against multiple climate threats.

With concerns of energy shortages, China, like the United States, European Union, and other countries, is promoting the development of biofuels. However, China also faces high future demand for food and feed, and so its bioenergy program must try to strike a balance between food and fuel. The goals of this paper are to provide an overview of China's current bioethanol program, identify the potential for using marginal lands for feedstock production, and measure the likely impacts of China's bioethanol development on the nation's future food self-sufficiency. Our results indicate that the potential to use marginal land for bioethanol feedstock production is limited. Applying a modeling approach based on highly disaggregated data by region, our analysis shows that the target of 10 million t of bioethanol by 2020 seems to be a prudent target, causing no major disturbances in China's food security. But the expansion of bioethanol may increase environmental pressures due to the higher levels of fertilizer use. This study shows also that if China were able to cultivate 45% of its required bioethanol feedstock on new marginal land, it would further limit negative effects of the bioethanol program on the domestic and international economy, but at the expense of having to apply another 750 thousand t of fertilizer.

Significant greenhouse gas (GHG) reductions from all sectors of human enterprise are necessary to avoid further effects and reduce the current effects of climate change. Agriculture and the global food system are estimated to contribute to one-third of all anthropogenic GHGs. In British Columbia, Canada, mandated GHG reduction targets and voluntary climate action programs are challenging local governments to include emission reduction targets, policies, and actions within official planning documents. At this early stage of GHG reductions, local government attention does not yet include agriculture but is directed toward the transportation, buildings, and waste management sectors. Given agriculture's contribution to GHG emissions and local government's engagement with GHG mitigation and food system planning, it seems reasonable to anticipate that over time, local governments should and will engage increasingly in reducing GHGs from agriculture. With the goal of advancing agriculture GHG mitigation by local governments, this paper reviews the jurisdictional powers governing agriculture and climate change within British Columbia. It examines how local governments can support mitigation within the sector through their roles in planning, policy, programming, and public engagement, and identifies potential research agenda items.

AbstractThe history of civilization is biased toward the use of bioenergy because of the biophysics of life and the structure of our natural environment. Energy physically drives the creation and maintenance of complex systems, which is shown here from simple molecular structures to empires. Only a fraction of the complexity currently supported by fossil fuels can be maintained using the energy in plant biomass alone, which is limited by global net primary productivity. From the dawn of civilization, agricultural land has always been used for energy for transportation, via feed for animals, and there has always been a trade‐off between ‘food, fuel, and environment’. The United States (USA), Germany, and Brazil now use roughly 12% of agricultural land for biofuels, but energy efficiency improvements by 2050 could require only 11% ofUSagricultural land or 15% of forest land for biofuels to support all modes ofUStransportation. Despite its limitations, bioenergy has been extensively used for thousands of years and probability theory suggests it will continue to be a critical energy resource. © 2013 Society of Chemical Industry and John Wiley & Sons, Ltd