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Cellulosic bioenergy is a primary land-based climate mitigation strategy, with soil carbon (C) storage and nitrogen (N) conservation as important mitigation elements. Here, we present 13 years of soil C and N change under three cellulosic cropping systems: monoculture switchgrass (Panicum virgatum L.), a five native grasses polyculture, and no-till corn (Zea mays L.). Soil C and N fractions were measured four times over 12 years. Bulk soil C in the 0–25 cm depth at the end of the study period ranged from 28.4 (± 1.4 se) Mg C ha−1 in no-till corn, to 30.8 (± 1.4) Mg C ha−1 in switchgrass, and to 34.8 (± 1.4) Mg C ha−1 in native grasses. Mineral-associated organic matter (MAOM) ranged from 60% to 90% and particulate organic matter (POM) from 10% to 40% of total soil C. Over 12 years, total C as well as both C fractions persisted under no-till corn and switchgrass and increased under native grasses. In contrast, POM N stocks decreased 33% to 45% across systems, whereas MAOM N decreased by less than 13% and only in no-till corn. Declining POM N stocks likely reflect pre-establishment land use, which included alfalfa and manure in earlier rotations. Root production and large soil aggregate formation explained 69% (p < 0.001) and 36% (p = 0.024) of total soil C change, respectively, and 60% (p = 0.020) and 41% (p = 0.023) of soil N change, demonstrating the importance of belowground productivity and soil aggregates for producing and protecting soil C and conserving soil N. Differences between switchgrass and native grasses also indicate a dependence on plant diversity. Soil C and N benefits of bioenergy crops depend strongly on root productivity and pre-establishment land use. See the Materials and Methods of the associated publication for procedures on sampling and processing, and section 2.9 Statistical analysis for statistical models. The R software was used for all analyses (R Core Team, 2014); the R scripts are provided in the file Statistical_Analysis.R. R Core Team. (2014). R: A language and environment for statistical computing. R Foundation for Statistical Computing. http://www.Rproject.org/ 

This paper presents a unique method for documenting and reflecting learning in interdisciplinary science learning settings, which prioritises the perspectives of marginalised learners and which may be used across cultural contexts. Short for “magazine” or “fanzine,” zines are small DIY booklets which can contain poetry, narrative, drawings, comics, collage and more. Often associated with radical or alternative cultures, they can become a kind of self-made soapbox for the creator, a material artifact that, by its very deconstructed and deconstructing nature, encourages a personalised remixing of ideas. Within this paper, we examine the practical and pedagogical positioning of zines within a STEAM (Science, Technology, Engineering, Arts, and Mathematics) context. As both a visual and text-based artifact, a zine is uniquely capable of capturing broad responses to diverse learning experiences which blur disciplinary boundaries and offers an inclusive and firmly emancipatory approach to reflective practice. 

Abstract Cellulosic bioenergy is a primary land‐based climate mitigation strategy, with soil carbon (C) storage and nitrogen (N) conservation as important mitigation elements. Here, we present 13 years of soil C and N change under three cellulosic cropping systems: monoculture switchgrass (Panicum virgatumL.), a five native grasses polyculture, and no‐till corn (Zea maysL.). Soil C and N fractions were measured four times over 12 years. Bulk soil C in the 0–25 cm depth at the end of the study period ranged from 28.4 (± 1.4 se) Mg C ha⁻¹in no‐till corn, to 30.8 (± 1.4) Mg C ha⁻¹in switchgrass, and to 34.8 (± 1.4) Mg C ha⁻¹in native grasses. Mineral‐associated organic matter (MAOM) ranged from 60% to 90% and particulate organic matter (POM) from 10% to 40% of total soil C. Over 12 years, total C as well as both C fractions persisted under no‐till corn and switchgrass and increased under native grasses. In contrast, POM N stocks decreased 33% to 45% across systems, whereas MAOM N decreased only in no‐till corn and by less than 13%. Declining POM N stocks likely reflect pre‐establishment land use, which included alfalfa and manure in earlier rotations. Root production and large soil aggregate formation explained 69% (p < 0.001) and 36% (p = 0.024) of total soil C change, respectively, and 60% (p = 0.020) and 41% (p = 0.023) of soil N change, demonstrating the importance of belowground productivity and soil aggregates for producing and protecting soil C and conserving soil N. Differences between switchgrass and native grasses also indicate a dependence on plant diversity. Soil C and N benefits of bioenergy crops depend strongly on root productivity and pre‐establishment land use.