Greenhouse gas mitigation with scarce land: The potential contribution of increased nitrogen input

Agricultural lands have been identified to mitigate greenhouse gas (GHG) emissions primarily by production of energy crops and substituting fossil energy resources and through carbon sequestration in soils. Increased fertilizer input resulting in increased yields may reduce the area needed for crop production. The surplus area could be used for energy production without affecting the land use necessary for food and feed production. We built a model to investigate the effect of changing nitrogen (N) fertilizer rates on cropping area required for a given amount of crops. We found that an increase in nitrogen fertilizer supply is only justified if GHG mitigation with additional land is higher than 9–15 t carbon dioxide equivalents per hectare (CO₂-eq._./ha). The mitigation potential of bioenergy production from energy crops is most often not in this range. Hence, from a GHG abatement point of view land should rather be used to produce crops at moderate fertilizer rate than to produce energy crops. This may change if farmers are forced to reduce their N input due to taxes or governmental regulations as it is the case in Denmark. However, with a fertilizer rate 10 % below the economical optimum a reduction of N input is still more effective than the production of bioenergy unless mitigation effect of the bioenergy production exceeds 7 t carbon dioxide (CO₂)-eq._./ha. An intensification of land use in terms of N supply to provide more land for bioenergy production can only in exceptional cases be justified to mitigate GHG emissions with bioenergy under current frame conditions in Germany and Denmark.     

Polyethylene microplastic toxicity to the terrestrial snail Cantareus aspersus: size matters

Environmental Science and Pollution Research - Plastic has become the most widespread human-made material and small fragments (< 5mm, so called microplastics, MPs) accumulate in all the...     

From bioavailability to risk assessment of polluted soil using snails: link between excess transfer and inhibition of sexual maturation

Environmental Science and Pollution Research - An accurate assessment of the environmental risk of soils contaminated by metal(loid)s (MEs) requires quantifying exposure and knowing the toxicity of...     

From environmental bioavailability of metal(loid)s to their ecogenotoxicological effects in land snails

Environmental Science and Pollution Research - To date, no study has linked the environmental and the ecogenotoxicological bioavailability of contaminants to land snails. Yet, understanding the...     

Air emission inventories in North America: a critical assessment

Although emission inventories are the foundation of air quality management and have supported substantial improvements in North American air quality, they have a number of shortcomings that can potentially lead to ineffective air quality management strategies. Major reductions in the largest emissions sources have made accurate inventories of previously minor sources much more important to the understanding and improvement of local air quality. Changes in manufacturing processes, industry types, vehicle technologies, and metropolitan infrastructure are occurring at an increasingly rapid pace, emphasizing the importance of inventories that reflect current conditions. New technologies for measuring source emissions and ambient pollutant concentrations, both at the point of emissions and from remote platforms, are providing novel approaches to collecting data for inventory developers. Advances in information technologies are allowing data to be shared more quickly, more easily, and processed and compared in novel ways that can speed the development of emission inventories. Approaches to improving quantitative measures of inventory uncertainty allow air quality management decisions to take into account the uncertainties associated with emissions estimates, providing more accurate projections of how well alternative strategies may work. This paper discusses applications of these technologies and techniques to improve the accuracy, timeliness, and completeness of emission inventories across North America and outlines a series of eight recommendations aimed at inventory developers and air quality management decision-makers to improve emission inventories and enable them to support effective air quality management decisions for the foreseeable future.     

Misunderstanding the “Nature” of Co-Management: A Geography of Regulatory Science and Indigenous Knowledges (IK)

Governments, NGOs, and natural scientists have increased research and policy-making collaborations with Indigenous peoples for governing natural resources, including official co-management regimes. However, there is continuing dissatisfaction with such collaborations, and calls for better communication and mutual learning to create more “adaptive” co-management regimes. This, however, requires that both Western and Indigenous knowledge systems be equal participants in the “co-production” of regulatory data. In this article, I examine the power dynamics of one co-management regulatory regime, conducting a multi-sited ethnography of the practices of researching and managing one transnational migratory species, greater white-fronted geese (Anser albifrons frontalis), who nest where Koyukon Athabascans in Alaska, USA, practice subsistence. Analyzing the ethnographic data through the literatures of critical geography, science studies and Indigenous Studies, I describe how the practice of researching for co-management can produce conflict. “Scaling” the data for the co-management regime can marginalize Indigenous understandings of human–environment relations. While Enlightenment-based practices in wildlife biology avoid “anthropomorphism,” Indigenous Studies describes identities that operate through non-modern, deeply imbricated human–nonhuman identities that do not separate “nature” and “society” in making knowledge. Thus, misunderstanding the “nature” of their collaborations causes biologists and managers to measure and research the system in ways that erase how subsistence-based Indigenous groups already “manage” wildlife: by living through their ethical commitments to their fellow beings. At the end of the article, I discuss how managers might learn from these ontological and epistemological differences to better “co-produce” data for co-management.