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The significance of nitrous oxide emission due to cropping of grain for biofuel production: a Swedish perspective
. Kasimir Klemedtsson,K. A. Smith
Biogeosciences (BG) & Discussions (BGD) , 2011,
Abstract: The current regulations governing production of biofuels in the European Union require that they have to mitigate climate change, by producing >35% less greenhouse gases (GHG) than fossil fuels. There is a risk that this may not be achievable, since land use for crop production inevitably emits the potent GHG nitrous oxide (N2O), due to nitrogen fertilisation and cycling in the environment. We analyse first-generation biofuel production on agricultural land and conclude that efficient agricultural crop production resulting in a good harvest and low N2O emission can fulfil the EU standard, and is possible under certain conditions for the Swedish agricultural and bioethanol production systems. However, in years having low crop yields, and where cropping is on organic soils, total GHG emissions per unit of fuel produced can be even higher than those released by burning of fossil fuels. In general, the N2O emission size in Sweden and elsewhere in northern Europe is such that there is a >50% chance that the 35% saving requirement will not be met. Thus ecosystem N2O emissions have to be convincingly assessed. Here we compare Swedish emission data with values estimated by means of statistical models and by a global, top-down, approach; the measurements and the predictions often show higher values that would fail to meet the EU standard and thus prevent biofuel production development.
Contrasting carbon dioxide fluxes between a drying shrub wetland in Northern Wisconsin, USA, and nearby forests
B. N. Sulman, A. R. Desai, B. D. Cook, N. Saliendra,D. S. Mackay
Biogeosciences (BG) & Discussions (BGD) , 2009,
Abstract: Wetland biogeochemistry is strongly influenced by water and temperature dynamics, and these interactions are currently poorly represented in ecosystem and climate models. A decline in water table of approximately 30 cm was observed at a wetland in Northern Wisconsin, USA over a period from 2001–2007, which was highly correlated with an increase in daily soil temperature variability. Eddy covariance measurements of carbon dioxide exchange were compared with measured CO2 fluxes at two nearby forests in order to distinguish wetland effects from regional trends. As wetland water table declined, both ecosystem respiration and ecosystem production increased by over 20% at the wetland, while forest CO2 fluxes had no significant trends. Net ecosystem exchange of carbon dioxide at the wetland was not correlated with water table, but wetland evapotranspiration decreased substantially as the water table declined. These results suggest that changes in hydrology may not have a large impact on shrub wetland carbon balance over inter-annual time scales due to opposing responses in both ecosystem respiration and productivity.
Patterns of mercury dispersion from local and regional emission sources, rural Central Wisconsin, USA  [PDF]
A. Kolker,M. L. Olson,D. P. Krabbenhoft,M. T. Tate
Atmospheric Chemistry and Physics Discussions , 2010,
Abstract: Simultaneous real-time changes in mercury (Hg) speciation – reactive gaseous Hg (RGM), elemental Hg (Hg°), and fine particulate Hg (Hg-PM2.5), were determined from June to November 2007, in ambient air at three locations in rural Central Wisconsin. Known Hg emission sources within the airshed of the monitoring sites include: 1) a 1114 megawatt (MW) coal-fired electric utility generating station; 2) a Hg-bed chlor-alkali plant; and 3) a smaller (465 MW) coal-burning electric utility. Monitoring sites, showing sporadic elevation of RGM, Hg° and Hg-PM2.5, were positioned at distances of 25, 50 and 100 km northward of the larger electric utility. A series of RGM events were recorded at each site. The largest, on 23 September, occurred under prevailing southerly winds, with a maximum RGM value (56.8 pg m 3) measured at the 100 km site, and corresponding elevated SO2 (10.41 ppbv; measured at 50 km site). The finding that RGM, Hg°, and Hg-PM2.5 are not always highest at the 25 km site, closest to the large generating station, contradicts the idea that RGM decreases with distance from a large point source. This may be explained if: 1) the 100 km site was influenced by emissions from the chlor-alkali facility or by RGM from regional urban sources; 2) the emission stack height of the larger power plant promoted plume transport at an elevation where the Hg is carried over the closest site; or 3) RGM was being generated in the plume through oxidation of Hg°. Operational changes at each emitter since 2007 should reduce their Hg output, potentially allowing quantification of the environmental benefit in future studies.
Population Change and Its Driving Factors in Rural, Suburban, and Urban Areas of Wisconsin, USA, 1970–2000  [PDF]
Guangqing Chi,Stephen J. Ventura
International Journal of Population Research , 2011, DOI: 10.1155/2011/856534
Abstract: Population growth (or decline) is influenced by many factors that fall into the broad realms of demographic characteristics, socioeconomic conditions, transportation infrastructure, natural amenities, and land use and development across space and time. This paper adopts an integrated spatial regression approach to investigate the spatial and temporal variations of these factors' effects on population change. Specifically, we conduct the analysis at the minor civil division level in Wisconsin, USA, from 1970 to 2000. The results suggest that the factors have varying effects on population change over time and across rural, suburban, and urban areas. Their effects depend upon the general trend of population redistribution processes, local dynamics, and areal characteristics. Overall, a systematic examination of population change should consider a variety of factors, temporal and spatial variation of their effects, and spatial spillover effects. The examination should have the flexibility to identify and incorporate influential factors at a given point in time and space, not to adhere to a single set of drivers in all circumstances. The findings have important implications for population predictions used for local and regional planning. 1. Introduction Land-use conflicts, regional/tribal warfare, environmental degradation, and competition for scarce resources are all exacerbated by growing populations. Holistic or systematic approaches are becoming critically important in tackling the complexity of development and population change [1–3]. Research findings have suggested that population growth (or decline) is determined jointly by demographic, social, economic, political, geographic, and cultural forces as well as temporal and spatial influences [4]. However, the majority of existing research is focused on only some of the factors and influences and does not consider others [5]. This might be due to the fact that development and population change are complex and require interdisciplinary knowledge, but existing studies are often conducted within disciplinary boundaries [3, 6]. In addition, simulating the complexity of population change requires well-grounded expertise in methodology, and putting together a dataset with a variety of variables across space and time is expensive. A wide range of results is possible by omitting relevant factors and influences from empirical models [7]. Therefore, because the various studies tend to focus on specific factors and influences within disciplinary boundaries and omit others, the existing research on population change
Patterns of mercury dispersion from local and regional emission sources, rural Central Wisconsin, USA
A. Kolker, M. L. Olson, D. P. Krabbenhoft, M. T. Tate,M. A. Engle
Atmospheric Chemistry and Physics (ACP) & Discussions (ACPD) , 2010,
Abstract: Simultaneous real-time changes in mercury (Hg) speciation- reactive gaseous Hg (RGM), elemental Hg (Hg°), and fine particulate Hg (Hg-PM2.5), were determined from June to November, 2007, in ambient air at three locations in rural Central Wisconsin. Known Hg emission sources within the airshed of the monitoring sites include: 1) a 1114 megawatt (MW) coal-fired electric utility generating station; 2) a Hg-bed chlor-alkali plant; and 3) a smaller (465 MW) coal-burning electric utility. Monitoring sites, showing sporadic elevation of Hg°, Hg-PM2.5, and RGM were positioned at distances of 25, 50 and 100 km northward of the larger electric utility. Median concentrations of Hg°, Hg-PM2.5, and RGM were 1.3–1.4 ng m 3, 2.6–5.0 pg m 3, and 0.6–0.8 pg m 3, respectively. A series of RGM events were recorded at each site. The largest, on 23 September, occurred under prevailing southerly winds, with a maximum RGM value (56.8 pg m-3) measured at the 100 km site, and corresponding elevated SO2 (10.4 ppbv; measured at 50 km site). The finding that RGM, Hg°, and Hg-PM2.5 are not always highest at the 25 km site, closest to the large generating station, contradicts the idea that RGM decreases with distance from a large point source. This may be explained if: 1) the 100 km site was influenced by emissions from the chlor-alkali facility or by RGM from regional urban sources; 2) the emission stack height of the larger power plant promoted plume transport at an elevation where the Hg is carried over the closest site; or 3) RGM was being generated in the plume through oxidation of Hg°. Operational changes at each emitter since 2007 should reduce their Hg output, potentially allowing quantification of the environmental benefit in future studies.
OBIS-USA: A Data-Sharing Legacy of the Census of Marine Life
George R. Sedberry,Daphne G. Fautin,Michael Feldman,Mark D. Fornwall
Oceanography , 2011,
Abstract: The United States Geological Survey’s Biological Informatics Program hosts OBIS-USA, the US node of the Ocean Biogeographic Information System (OBIS). OBIS-USA gathers, coordinates, applies standard formats to, and makes widely available data on biological collections in marine waters of the United States and other areas where US investigators have collected data and, in some instances, specimens. OBIS-USA delivers its data to OBIS international, which then delivers its data to the Global Biodiversity Information Facility (GBIF) and other Web portals for marine biodiversity data. OBIS-USA currently has 145 data sets from 36 participants, representing over 6.5 million occurrence records of over 83,000 taxa from more than 888,000 locations. OBIS-USA, a legacy of the decade-long (2001–2010) international collaborative Census of Marine Life enterprise, continues to add data, including those from ongoing Census projects. Among the many challenges in creating OBIS, including OBIS-USA, were developing a community of trust and shared value among data providers, and demonstrating to providers the value of making their data accessible to others. Challenges also posed by the diversity of data sets relevant to marine biodiversity stored on thousands of computers, in a variety of formats, not all widely accessible, have been met in OBIS-USA by implementing a uniform standard and publishing platform that is easily accessible to a broad range of users.
Gone with transgenic cotton cropping in the USA. A perception of the presentations and interactions at the Beltwide Cotton Conferences, New Orleans (Louisiana, USA), 4-7/01/2010  [PDF]
Fok, M.
Biotechnologie, Agronomie, Société et Environnement , 2011,
Abstract: The 2010 Beltwide Cotton Conferences provided a new vision of the consequences of about 15 years of widespread and uncoordinated cropping of transgenic cotton in the United States. Insect-resistant and/or herbicide-tolerant cotton varieties modified parasite complexes, namely those of insects and weeds damaging cotton crops. The Conferences have revealed that the adaptation solutions so far proposed make illusory the expectations at the launch of transgenic cotton, in terms of effective pest control, cost reduction, and antagonism between chemical and biotech methods. The USA case points out that the technical and economic sustainability of transgenic varieties must lie in a systemic and coordinated approach.
Development of Profitable Phytoremediation of Contaminated Soils with Biofuel Crops  [PDF]
Kokyo Oh, Tao Li, Hongyan Cheng, Xuefeng Hu, Chiquan He, Lijun Yan, Yonemochi Shinichi
Journal of Environmental Protection (JEP) , 2013, DOI: 10.4236/jep.2013.44A008
Abstract:

Contamination of agricultural soil has been a worldwide concern, and phytoremediation is a promising alternative to conventional soil clean-up technology as a low cost and environment-friendly technology. However, the field application of phytoremediation is still limited, because of its low efficiency and long-period needed. In this paper, with discussion of the characteristics, mechanisms and development of phytoremediation, we suggested a profitable phytoremediation strategy using biofuel crops for both utilization and remediation of contaminated soil. In this strategy, the owners of contaminated sites possibly cost nothing, but obtain income through selling the biofuel crop for factories produced biofuel, thus the practical application of phytoremediation can be effectively promoted. In order to test the feasibility of the suggested strategy, a hydroponic cultural experiment and a pot experiment were carried out to assess the phytoremediation potential of some biofuel crops. The hydroponic cultural experiment showed that the two biofuel plants, sunflower and maize, had a better or similar accumulation level of Pb, Cu and Cd than the two accumulator plants. The pot cultural experiment showed that wheat and barley with white-rot-fungus inoculation greatly promoted crop biomass, soil microbial population, and dioxins removal efficiency. These results indicate that phytoremediation using biofuel plants possibly works effectively for remediation of contaminated soils as well as provide economic benefits to the owners of contaminated sites. Therefore, biofuel crops would be a reasonable choice for phytoremediation of contaminated soils.

The Wisconsin Plasma Astrophysics Laboratory  [PDF]
C. B. Forest,K. Flanagan,M. Brookhart,C. M. Cooper,M. Clark,V. Desangles,J. Egedal,D. Endrizzi,M. Miesch,I. V. Khalzov,H. Li,J. Milhone,M. Nornberg,J. Olson,E. Peterson,F. Roesler,A. Schekochihin,O. Schmitz,R. Siller,A. Spitkovsky,A. Stemo,J. Wallace,D. Weisberg,E. Zweibel
Physics , 2015, DOI: 10.1017/S0022377815000975
Abstract: The Wisconsin Plasma Astrophysics Laboratory (WiPAL) is a flexible user facility designed to study a range of astrophysically relevant plasma processes as well as novel geometries that mimic astrophysical systems. A multi-cusp magnetic bucket constructed from strong samarium cobalt permanent magnets now confines a 10 m$^3$, fully ionized, magnetic-field free plasma in a spherical geometry. Plasma parameters of $ T_{e}\approx5$ to $20$ eV and $n_{e}\approx10^{11}$ to $5\times10^{12}$ cm$^{-3}$ provide an ideal testbed for a range of astrophysical experiments including self-exciting dynamos, collisionless magnetic reconnection, jet stability, stellar winds, and more. This article describes the capabilities of WiPAL along with several experiments, in both operating and planning stages, that illustrate the range of possibilities for future users.
The LEP Legacy  [PDF]
Giorgio Giacomelli,Roberto Giacomelli
Physics , 2005,
Abstract: In this lecture we shall summarize the scientific legacy of LEP, in particular in connection with the Standard Model of Particle Physics; we shall also discuss some historical and sociological aspects of the experimentation at LEP.
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