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891.
Biochar and hydrochar effects on greenhouse gas (carbon dioxide, nitrous oxide, and methane) fluxes from soils 总被引:5,自引:0,他引:5
With a growing world population and global warming, we are challenged to increase food production while reducing greenhouse gas (GHG) emissions. We studied the effects of biochar (BC) and hydrochar (HC) produced via pyrolysis or hydrothermal carbonization, respectively, on GHG fluxes in three laboratory incubation studies. In the first experiment, ryegrass was grown in sandy loam mixed with equal amounts of a nitrogen-rich peanut hull BC, compost, BC+compost, double compost, or no addition (control); wetting-drying cycles and N fertilization were applied. Biochar with or without compost significantly reduced NO emissions and did not change the CH uptake, whereas ryegrass yield was significantly increased. In the second experiment, 0% (control) or 8% (w/w) of BC (peanut hull, maize, wood chip, or charcoal) or 8% HC (beet chips or bark) was mixed into a soil and incubated at 65% water-holding capacity (WHC) for 140 d. Treatments included simulated plowing and N fertilization. All BCs reduced NO emissions by ~60%. Hydrochars reduced NO emissions only initially but significantly increased them after N fertilization to 302% (HC-beet) and 155% (HC-bark) of the control emissions, respectively. Large HC-associated CO emissions suggested that microbial activity was stimulated and that HC was less stable than BC. In the third experiment, nutrient-rich peanut hull BC addition and incubation over 1.5 yr at high WHCs did not promote NO emissions. However, NO emissions were significantly increased with BC after NHNO addition. In conclusion, BC reduced NO emissions and improved the GHG-to-yield ratio under field-relevant conditions. However, the risk of increased NO emissions with HC addition must be carefully evaluated. 相似文献
892.
Silvia Espín Jovan Andevski Guy Duke Igor Eulaers Pilar Gmez-Ramírez Gunnar Thor Hallgrimsson Bjrn Helander Dorte Herzke Veerle L. B. Jaspers Oliver Krone Rui Loureno Pedro María-Mojica Emma Martínez-Lpez Rafael Mateo Paola Movalli Pablo Snchez-Virosta Richard F. Shore Christian Sonne Nico W. van den Brink Bert van Hattum Al Vrezec Chris Wernham Antonio J. García-Fernndez 《Ambio》2021,50(1):95
Birds of prey, owls and falcons are widely used as sentinel species in raptor biomonitoring programmes. A major current challenge is to facilitate large-scale biomonitoring by coordinating contaminant monitoring activities and by building capacity across countries. This requires sharing, dissemination and adoption of best practices addressed by the Networking Programme Research and Monitoring for and with Raptors in Europe (EURAPMON) and now being advanced by the ongoing international COST Action European Raptor Biomonitoring Facility. The present perspective introduces a schematic sampling protocol for contaminant monitoring in raptors. We provide guidance on sample collection with a view to increasing sampling capacity across countries, ensuring appropriate quality of samples and facilitating harmonization of procedures to maximize the reliability, comparability and interoperability of data. The here presented protocol can be used by professionals and volunteers as a standard guide to ensure harmonised sampling methods for contaminant monitoring in raptors.Electronic supplementary materialThe online version of this article (10.1007/s13280-020-01341-9) contains supplementary material, which is available to authorized users. 相似文献
893.
Jarle EidKathryn Mearns Gerry LarssonJon Christian Laberg Bjørn Helge Johnsen 《Safety Science》2012,50(1):55-61
In this theory-driven literature review we examine how leadership and emerging research in positive organizational behaviour (POB) may inform our understanding of human mechanisms that affect safety outcomes. According to authentic leadership theory, leader self-awareness and self-regulation processes are vital mechanisms in the leader-follower exchange. From emerging research on authentic leadership, we propose that production management values, attitudes, and behaviour are linked to safety climate and safety outcomes in safety critical organizations (SCOs). According to recent developments in management theory, “psychological capital” is comprised of four distinct aspects that can be linked to desirable organizational outcomes and sustained high quality performance in individual workers. From this we offer a research model and five research propositions implicating that authentic leadership directly affects safety outcomes via promoting positive safety climate perceptions. Furthermore, we propose a second path where psychological capital mediates the relationship between authentic leadership, safety climate and safety outcomes in SCOs. 相似文献
894.
Touma JS Isakov V Ching J Seigneur C 《Journal of the Air & Waste Management Association (1995)》2006,56(5):547-558
The current requirements and status of air quality modeling of hazardous pollutants are reviewed. Many applications require the ability to predict the local impacts from industrial sources or large roadways as needed for community health characterization and evaluating environmental justice concerns. Such local-scale modeling assessments can be performed by using Gaussian dispersion models. However, these models have a limited ability to handle chemical transformations. A new generation of Eulerian grid-based models is now capable of comprehensively treating transport and chemical transformations of air toxics. However, they typically have coarse spatial resolution, and their computational requirements increase dramatically with finer spatial resolution. The authors present and discuss possible advanced approaches that can combine the grid-based models with local-scale information. 相似文献
895.
Meinelt T Schreckenbach K Pietrock M Heidrich S Steinberg CE 《Environmental science and pollution research international》2008,15(1):17-22
GOALS, SCOPE AND BACKGROUND: Changing environmental conditions and handling stress are well known to cause chronic or acute stress situations in fish with subsequent infections. These requires a therapy by means of antibiotics and chemicals. In contrast to the huge number of pathogens, only a few substances are permitted for application as therapeutics in German aquaculture. Hence, there emerges an urgent need for highly effective and residueless alternatives. MAIN FEATURES: The prophylactic stimulation and training of the defense system of fish by alternative approaches becomes increasingly necessary. One approach is the application of dissolved humic substances (HS) of natural or artificial origin. For example, there exist several reports on the positive effect of HS to fishes. These effects shall be considered in detail. Furthermore, the impact of HS on the constitution of parasites and pathogens will be displayed. The reports on this issue are diverse, if not inconsistent. We try to shed some light on these discrepancies. The last aspect covered by this review is the outdated paradigm that calcium ions act as antidotes. In the presence of HS, even the opposite effect may occur. APPROACH: To overcome old paradigms on HS and their potential interactions with fish and fish parasites, we reviewed recent international literature, as well as 'grey' literature. We also include results from own former and ongoing studies. RESULTS AND DISCUSSION: HS are able to increase the physiological condition of the individuals and to reduce adverse physiological and histological consequences caused by stress; the mechanism behind remains obscure. HS detoxify heavy metals and organic pollutants. Damages caused by several fish pathogens, such as bacteria and parasites, can be repaired more quickly in the presence of HS. Some parasites--mainly fungi--appear to be directly affected by HS. Comparing the fungicidal effects of HS from various sources, evidence is increasing that the aliphatic moiety may be the effective structures. However, further research is necessary to relate more physiological and anti-pathogenic effects to the chemical characteristics of HS. CONCLUSIONS: HS are not real alternatives to strong traditional therapeutics. However, they show different advantages in repairing secondary, stress induced damages in fish. The ecophysiological relevance of HS in either aquatic systems or aquaculture is getting conspicuously. PERSPECTIVES: The lack of therapeutic and antiparasitic substances in aquaculture requires new strategies and ways of thinking. The search for alternatives to the 'traditional' chemical therapeutics calls for the intensive research. Inevitably, this search will lead to an intensive contemplation on HS as 'health promoting substances' and/or even therapeutics. Basic research is needed to detect the functional groups of the HS responsible for the effects observed. Health promoting effects of first investigations made in vitro to affect pathogens via application of HS and several field studies with HS raises hopes for a broader utilisation of HS to reduce stress consequences in fish and fish pathogens residuelessly. 相似文献
896.
Gégo E Gilliland A Godowitch J Rao ST Porter PS Hogrefe C 《Journal of the Air & Waste Management Association (1995)》2008,58(4):580-588
In this paper, we examine the changes in ambient ozone concentrations simulated by the Community Multiscale Air Quality (CMAQ) model for summer 2002 under three different nitrogen oxides (NOx) emission scenarios. Two emission scenarios represent best estimates of 2002 and 2004 emissions; they allow assessment of the impact of the NOx emissions reductions imposed on the utility sector by the NOx State Implementation Plan (SIP) Call. The third scenario represents a hypothetical rendering of what NOx emissions would have been in 2002 if no emission controls had been imposed on the utility sector. Examination of the modeled median and 95th percentile daily maximum 8-hr average ozone concentrations reveals that median ozone levels estimated for the 2004 emission scenario were less than those modeled for 2002 in the region most affected by the NOx SIP Call. Comparison of the "no-control" with the "2002" scenario revealed that ozone concentrations would have been much higher in much of the eastern United States if the utility sector had not implemented NOx emission controls; exceptions occurred in the immediate vicinity of major point sources where increased NO titration tends to lower ozone levels. 相似文献
897.
Eleven drinking water treatment plants, located downstream of textile plants or pulp and paper mills, have been sampled monthly during a year for the analysis of 17 nonylphenol ethoxylates (NP1-17EO) and two nonylphenoxycarboxylic acids (NP1-2EC). At all but one plant, results in the drinking water, for the sum of these 19 substances, range between below detection levels and 6.7 microg/l. Annual means are between 0.02 and 2.8 microg/l. At the other plant, the yearly average concentration is 10.4 microg/l and the monthly maximum is 43.3 microg/l. In the surface (pre-treatment) water, the annual mean concentrations of the 11 plants range between 0.14 and 17.8 microg/l and the recorded instantaneous maximum is 55.3 microg/l. According to Canadian health authorities, drinking water is a negligible route of human exposure to nonylphenolic compounds, even at the highest concentrations found in this study. After transformation of the data into nonylphenol equivalents, about 20% of the surface water samples exceed the Canadian 1 microg/l nonylphenol water quality guideline for the protection of aquatic life. Some results also exceed Québec's 6 microg/l nonylphenol guideline. The efficiency of the plants in removing nonylphenolic compounds from drinking water is highly variable, ranging from 11% to 99%. 相似文献
898.
Christian Kuhlicke Annett Steinführer Chloe Begg Chiara Bianchizza Michael Bründl Matthias Buchecker Bruna De Marchi Marina Di Masso Tarditti Corina Höppner Bla? Komac Louis Lemkow Jochen Luther Simon McCarthy Luigi Pellizzoni Ortwin Renn Anna Scolobig Meera Supramaniam Sue Tapsell Gisela Wachinger Gordon Walker Rebecca Whittle Matija Zorn Hazel Faulkner 《Environmental Science & Policy》2011,14(7):804-814
Social capacity building for natural hazards is a topic increasingly gaining relevance not only for so-called developing countries but also for European welfare states which are continuously challenged by the social, economic and ecological impacts of natural hazards. Following an outline of recent governance changes with regard to natural hazards, we develop a heuristic model of social capacity building by taking into account a wide range of existing expertise from different fields of research. Particular attention is paid to social vulnerability and its assessment, as well as to risk communication and risk education as specific strategies of social capacity building. We propose to distinguish between interventionist and participatory approaches, thus enabling for a better understanding of existing practices of social capacity building as well as their particular strengths and weaknesses. By way of conclusion, we encourage more research on social capacity building for natural hazards in the European context which at present is highly diverse and, at least in parts, only poorly investigated. 相似文献
899.
Factors affecting trace element content in periurban market garden subsoil in Yunnan Province, China 总被引:1,自引:0,他引:1
Field investigations were conducted to measure subsoil trace element content and factors influencing content in an intensive periurban market garden in Chenggong County,Yunnan Province,South-West China.The area was divided into three different geomorphological units:specifically,mountain (M),transition (T) and lacustrine (L).Mean trace element content in subsoil were determined for Pb (58.2 mg/kg),Cd (0.89 mg/kg),Cu (129.2 mg/kg),and Zn (97.0 mg/kg).Strong significant relationships between trace element con... 相似文献
900.
The lower troposphere is an excellent receptacle, which integrates anthropogenic greenhouse gases emissions over large areas. Therefore, atmospheric concentration observations over populated regions would provide the ultimate proof if sustained emissions changes have occurred. The most important anthropogenic greenhouse gas, carbon dioxide (CO(2)), also shows large natural concentration variations, which need to be disentangled from anthropogenic signals to assess changes in associated emissions. This is in principle possible for the fossil fuel CO(2) component (FFCO(2)) by high-precision radiocarbon ((14)C) analyses because FFCO(2) is free of radiocarbon. Long-term observations of (14)CO(2) conducted at two sites in south-western Germany do not yet reveal any significant trends in the regional fossil fuel CO(2) component. We rather observe strong inter-annual variations, which are largely imprinted by changes of atmospheric transport as supported by dedicated transport model simulations of fossil fuel CO(2). In this paper, we show that, depending on the remoteness of the site, changes of about 7-26% in fossil fuel emissions in respective catchment areas could be detected with confidence by high-precision atmospheric (14)CO(2) measurements when comparing 5-year averages if these inter-annual variations were taken into account. This perspective constitutes the urgently needed tool for validation of fossil fuel CO(2) emissions changes in the framework of the Kyoto protocol and successive climate initiatives. 相似文献