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S.J.Lennon 《生态毒理学报》2001,23(3):34-37
本文概括了12个南部非洲国家电力联营的一体化电力计划(IEP)过程,阐述了使用IEP的长期计划,本文同时也着重讨论了关于未来生产量的决策过程,提出了有利于在南非采纳更清洁技术的角色和措施. 相似文献
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Eoin O’Neill Catherine Devitt Mick Lennon Phoebe Duvall Laura Astori Ruaidhri Ford 《Environmental Communication: A Journal of Nature and Culture》2018,12(4):451-461
Policy reform can be complex and fraught with contending arguments. Although much research has been conducted into the politics of coalition formation, less attention has been devoted to legitimating logics in policy reform. Drawing on the work of Boltanski and Thévenot, this exploratory study addresses this deficit by examining the influence of justifications deployed in policy debates. The paper analyses the role of shifting reasoning in contentious debates concerning attempts to reform water policy, including the introduction of domestic water charges in Ireland. Employing data from parliamentary deliberations, the paper traces the changing forms of justification used by those favouring and opposing the reforms. This examination suggests the importance of aligning an argument’s content with the shifting context into which it is introduced. The paper highlights the benefits of an investigative approach concerning policy justification for understanding policy reform dynamics at the intersection of politics and environmental communication. 相似文献
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S.?A.?PouletEmail author M.?Richer de Forges A.?Cueff J.-F.?Lennon 《Marine Biology》2003,143(5):889-895
Two double-labelling methods, Tunel+propidium iodide and Annexin V-FITC+propidium iodide, have been tested to diagnose cell degradation processes in N1–N2 nauplius stages produced by spawning females of the copepod Calanus helgolandicus fed either non-toxic (PRO: control) or toxic (TR1) diets under laboratory conditions. Observation of labelled samples with a confocal laser-scanning microscope revealed that the maternal-food effect, following absorption of the toxic diet, induced cell apoptosis and necrosis in 80–100% of the offspring, which sooner or later died. Similar cell damages were also observed in 18–50% of the nauplii produced by females incubated in filtered seawater. Such cell degradation processes and high mortality were not observed in nauplii produced by females fed the non-toxic diet. Our protocols allowed detection of cell degradations before death of unhealthy larvae, preferentially with a confocal microscope or a conventional visible-fluorescent-light microscope.Communicated by O. Kinne, Oldendorf/Luhe 相似文献
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The rate, timing, and quality of resource supply exert strong controls on a wide range of ecological processes. In particular, resource-mediated changes in microbial activity have the potential to alter ecosystem processes, including the production and respiration of organic matter. In this study, we used field experiments and simulation modeling to explore how aquatic heterotrophic bacteria respond to variation in resource quality (low vs. high) and resource schedule (pulse vs. press). Field experiments revealed that one-time pulse additions of resources in the form of dissolved organic carbon (DOC) caused short-lived (< or =48 h) peaks in bacterial productivity (BP), which translated into large differences across treatments: cumulative BP was twice as high in the pulse vs. press treatment under low resource quality, and five times as high under high resource quality. To gain a more mechanistic understanding of microbial productivity in variable resource environments, we constructed a mathematical model to explore the attributes of bacterial physiology and DOC supply that might explain the patterns observed in our field experiments. Model results suggest that the mobilization rate of refractory to labile carbon, an index of resource quality, was critical in determining cumulative differences in BP between pulse and press resource environments (BPPu:Pr ratios). Moreover, BPPu:Pr ratios were substantially larger when our model allowed for realistic changes in bacterial growth efficiency as a function of bacterial carbon consumption. Together, our field and modeling results imply that resource schedule is important in determining the flow of material and energy from microbes to higher trophic levels in aquatic food webs, and that the effects of resource quality are conditional upon resource schedule. An improved understanding of the effects of resource variability on microorganisms is therefore critical for predicting potential changes in ecosystem functioning in response to environmental change, such as altered DOC fluxes from terrestrial to aquatic ecosystems. 相似文献
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We examined variability in hierarchical beta diversity across ecosystems, geographical gradients, and organism groups using multivariate spatial mixed modeling analysis of two independent data sets. The larger data set comprised reported ratios of regional species richness (RSR) to local species richness (LSR) and the second data set consisted of RSR:LSR ratios derived from nested species-area relationships. There was a negative, albeit relatively weak, relationship between beta diversity and latitude. We found only relatively subtle differences in beta diversity among the realms, yet beta diversity was lower in marine systems than in terrestrial or freshwater realms. Beta diversity varied significantly among organisms' major characteristics such as body mass, trophic position, and dispersal type in the larger data set. Organisms that disperse via seeds had highest beta diversity, and passively dispersed organisms showed the lowest beta diversity. Furthermore, autotrophs had lower beta diversity than organisms higher up the food web; omnivores and carnivores had consistently higher beta diversity. This is evidence that beta diversity is simultaneously controlled by extrinsic factors related to geography and environment, and by intrinsic factors related to organism characteristics. 相似文献
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Jim Lennon 《Natural resources forum》1990,14(3):187-192
The average LME nickel price in 1988 was $6.26/lb and in 1989 was $6.00/lb. This contrasts with an average price of $2.11/lb over the period 1982–87. The reasons for this run up on price include increased demand for stainless steel (the largest use of nickel), reflecting the period of sustained economic growth in the OECD countries, and the decline in market stocks which reached unusually low levels in 1987 and 1988. Forecasts of nickel supply and demand for 1990 and beyond are presented and the need for additional capacity estimated. In general new greenfield capacity will not be needed until the late 1990s. 相似文献
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Environmental Fluid Mechanics - We introduce a mathematical model with a mesh-free numerical method to describe contact-line motion in lubrication theory. We show how the model resolves the... 相似文献
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Mick Lennon 《Local Environment》2015,20(8):957-980
Advocates of the green infrastructure (GI) concept claim it offers a progressive planning approach that facilitates synergies between economic growth, environmental conservation and social development. Although widely endorsed by both planning practitioners and academics, little academic literature exists critically evaluating what GI entails or the potential implications of its institutionalisation within planning practice. This paper addresses this deficit by critically examining the interpretation and representation of the GI concept in planning policy. The paper first critically analyses international interpretations of GI. Following this, the particular attributes of GI's interpretation in the Republic of Ireland are investigated. The paper demonstrates how the emergence of GI in Ireland relates to broader debates on attempts to reconcile environmental concerns with development aspirations in planning policy. It is deduced that GI may represent an approach to planning policy formulation wherein habitat conservation initiatives are primarily designed and justified relative to the ecosystems services they are seen to provide to society. The paper also cautions against the risks posed by confining GI debates to the deliberations of technical specialist. The paper concludes by identifying some issues that may arise in the implementation of a GI approach and suggests ways to enhance the potential benefit of the concept's use in spatial planning. 相似文献