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481.
Carl Death 《环境政策》2016,25(1):116-135
Whilst the ‘green state debate’ has primarily focused on a narrow range of usual suspects in the developed world, the debate can be enriched and challenged by considering more diverse cases. Viewing African states from a green state perspective invites empirical reassessment of the geographical scope of the concept, and introduces a new set of conceptual questions about the political significance of transitions in environmental governance. Ecological modernisation theory has largely neglected African states because it is assumed that African states are weak, failing, or failed, and that environmentalism is a post-materialist phenomenon. Whilst both assumptions can be challenged empirically, a biopolitical perspective on the African environmental state, drawing on the work of Michel Foucault, can both position African state development within a longer-term context and challenge some assumptions of ecological modernisation. Examples from Egypt, South Africa, and the Kavango-Zambezi Trans-frontier Conservation Area highlight underestimated continuities in environmental state practices. The international and transnational drivers of the green state in Africa are emphasised, as well as the political dangers of a green ‘state building’ project. 相似文献
482.
The study showed that the open water of the Bothnian Sea (BS) is likely to have shifted from altering nitrogen and phosphorous limitations of the spring bloom to more nitrogen-limited conditions during the last 20 years. This is affected by the by inflow of phosphate-rich and oxygen-depleted water from depths near the halocline in the northern Baltic Proper, where severe oxygen conditions currently cause extreme phosphate concentrations in the deep water. The change in relation between inorganic nitrogen and phosphorous in the BS occurs first in the deep water and then progresses to the surface water. The change can potentially cause increased production in the BS and more frequent cyanobacterial blooms. There does not appear to be any immediate concern in the short-term perspective for the state of the BS, but a progression of the processes may lead to a more eutrophic state of the BS.
Electronic supplementary material
The online version of this article (doi:10.1007/s13280-015-0675-3) contains supplementary material, which is available to authorized users. 相似文献483.
Yohannes Yared Beyene Ikenaka Yoshinori Ito Gengo Nakayama Shouta M. M. Mizukawa Hazuki Wepener Victor Smit Nico J. Van Vuren Johan H. J. Ishizuka Mayumi 《Environmental science and pollution research international》2017,24(30):23763-23770
Environmental Science and Pollution Research - Ethiopia and South Africa are among the few countries to still implement indoor residual spraying with dichloro-diphenyl-trichloroethane (DDT) for... 相似文献
484.
Judith Schleicher Johanna Eklund Megan D. Barnes Jonas Geldmann Johan A. Oldekop Julia P. G. Jones 《Conservation biology》2020,34(3):538-549
The awareness of the need for robust impact evaluations in conservation is growing and statistical matching techniques are increasingly being used to assess the impacts of conservation interventions. Used appropriately matching approaches are powerful tools, but they also pose potential pitfalls. We outlined important considerations and best practice when using matching in conservation science. We identified 3 steps in a matching analysis. First, develop a clear theory of change to inform selection of treatment and controls and that accounts for real-world complexities and potential spillover effects. Second, select the appropriate covariates and matching approach. Third, assess the quality of the matching by carrying out a series of checks. The second and third steps can be repeated and should be finalized before outcomes are explored. Future conservation impact evaluations could be improved by increased planning of evaluations alongside the intervention, better integration of qualitative methods, considering spillover effects at larger spatial scales, and more publication of preanalysis plans. Implementing these improvements will require more serious engagement of conservation scientists, practitioners, and funders to mainstream robust impact evaluations into conservation. We hope this article will improve the quality of evaluations and help direct future research to continue to improve the approaches on offer. 相似文献
485.
Brent W. Hall Carl Singer Wojciech Jozewicz Charles B. Sedman Michael A. Maxwell 《Journal of the Air & Waste Management Association (1995)》2013,63(1):103-110
The following report discusses current bench- and pilot-plant advances in preparation of ADVAnced siliCATE (ADVACATE) calcium silicate sorbents for flue gas desulfurization. It also discusses current bench- and pilot-plant advances in sorbent preparation. Fly ash was ground in a laboratory scale grinder prior to slurring in order to decrease the slurring time needed for the sorbent to be reactive with SO2. Reactivity of ADVACATE sorbents with SO2 in the bench-scale reactor correlated with their surface area. ADVACATE sorbents produced with ground fly ash were evaluated in the 50 cfm (85 m3/h) pilot plant providing 2 s duct residence time. ADVACATE sorbent was produced by slurrying ground fly ash (median particle size of 4.3 µm) with Ca(OH)2 at the weight ratio of 3:1 at 90°C (194°F) for 3hto yield solids with 30 weight percent of initial free moisture. When this sorbent was injected into the duct with 1500 ppm SO2 and at 11°C (20°F) approach to saturation, the measured SO2 removal was approximately 60percent at a Ca/S stoichiometric ratio of 2. Previously, when ADVACATE sorbent was produced at 90°C (194°F) and at the same fly-ash-to-Ca(OH)2 weight ratio using unground fly ash, removal under the same conditions in the duct was approximately 50 percent following 12 h slurring. The report presents the results of pilot-scale recycle tests at the recycle ratio of 2. Finally, the report discusses future U.S. Environmental Protection Agency plans for commercialization of ADVACATE. 相似文献
486.
Carl Ensfield Jay Gordon Jr. Jim Lindner 《Journal of the Air & Waste Management Association (1995)》2013,63(9):1098-1108
Abstract A study was performed at a Gordon-Darby centralized inspection and maintenance (I/M) test lane in Phoenix, AZ, in December 1999 for the purpose of evaluating the accuracy of production Vehicle Mass Analysis System (VMAS) equipment relative to standard IM240 equipment. Simultaneous transient mass measurements were made on random vehicles using VMAS and IM240 systems on two test lanes during regular I/M testing. Cumulative mass emissions for 846 valid tests were correlated using least-squares regression analysis. Correlation indices were >0.99 for both carbon monoxide (CO) and nitric oxide (NO) and 0.93 for hydrocarbon (HC), and the standard errors of regression were 1.38 g/mi, 0.123 g/mi, and 0.245 g/mi for CO, NO, and HC, respectively. These strong correlation results are reflected by high excess emission identification rates of 99.4% for CO, 99.3% for NO, and 94.5% for HC when applying final IM240 cut points with a <2% error of commission for all pollutants. 相似文献
487.
Many chemicals in use today lack appropriate documentation on their environmental properties, fate, and effects. To counteract this lack of documentation it is vital to thoroughly investigate a compound’s fate in the environment before it comes into use. The present study is describing a novel method for assessing the reduction potential of polybrominated diphenyl ethers (PBDEs), as a part of a project aimed to create an experimental model for determination of chemical persistence. The reductive transformation of 15 PBDE congeners using sodium borohydride was determined. Pseudo-first-order reaction rate constants of the transformations were determined by monitoring the disappearance of the investigated congeners. The reductions lead primarily to formation of lower brominated PBDEs. Each PBDE congener was tested in a total of ten replicates which showed a relative standard deviation of 31% or less. The decaBDE, BDE-209 was approximately 3 times as prone to reductive transformation as BDE-207. The three nonaBDEs, BDE-206, BDE-207, and BDE-208, showed similar reductive potential. The reactivity of the tested octaBDEs was quite variable, from 5% to 24% of the reactivity of BDE-209 for BDE-196 and BDE-198, respectively. The heptaBDEs studied were in the range of the less reactive octaBDEs, except for BDE-181 which was as high as 13% of the reactivity of BDE-209. The results presented give a method for measuring the propensity of PBDEs, and possibly similar compounds, to undergo reductions. They indicate a potential route to a vital piece of information in the assessment of environmental persistence of chemicals. 相似文献
488.
Forest Fragmentation and Landscape Transformation in a Reindeer Husbandry Area in Sweden 总被引:1,自引:0,他引:1
Reindeer husbandry and forestry are two main land users in boreal forests in northern Sweden. Modern forestry has numerous
negative effects on the ground-growing and arboreal lichens that are crucial winter resources for reindeer husbandry. Using
digitized historical maps, we examined changes in the forest landscape structure during the past 100 years, and estimated
corresponding changes in suitability of forest landscape mosaics for the reindeer winter grazing. Cover of old coniferous
forests, a key habitat type of reindeer herding system, showed a strong decrease during the study period, whereas clear-cutting
and young forests increased rapidly in the latter half of the 20th century. The dominance of young forests and fragmentation
of old-growth forests (decreased patch sizes and increased isolation) reflect decreased amount of arboreal lichens as well
as a lowered ability of the landscape to sustain long-term persistence of lichens. The results further showed that variation
in ground lichen cover among sites was mainly related to soil moisture conditions, recent disturbances, such as soil scarification
and prescribed burning, and possibly also to forest history. In general, the results suggest that the composition and configuration
of the forest landscape mosaic has become less suitable for sustainable reindeer husbandry. 相似文献
489.
Humanity has entered a new phase of sustainability challenges, the Anthropocene, in which human development has reached a
scale where it affects vital planetary processes. Under the pressure from a quadruple squeeze—from population and development
pressures, the anthropogenic climate crisis, the anthropogenic ecosystem crisis, and the risk of deleterious tipping points
in the Earth system—the degrees of freedom for sustainable human exploitation of planet Earth are severely restrained. It
is in this reality that a new green revolution in world food production needs to occur, to attain food security and human
development over the coming decades. Global freshwater resources are, and will increasingly be, a fundamental limiting factor
in feeding the world. Current water vulnerabilities in the regions in most need of large agricultural productivity improvements
are projected to increase under the pressure from global environmental change. The sustainability challenge for world agriculture
has to be set within the new global sustainability context. We present new proposed sustainability criteria for world agriculture,
where world food production systems are transformed in order to allow humanity to stay within the safe operating space of
planetary boundaries. In order to secure global resilience and thereby raise the chances of planet Earth to remain in the
current desired state, conducive for human development on the long-term, these planetary boundaries need to be respected.
This calls for a triply green revolution, which not only more than doubles food production in many regions of the world, but
which also is environmentally sustainable, and invests in the untapped opportunities to use green water in rainfed agriculture
as a key source of future productivity enhancement. To achieve such a global transformation of agriculture, there is a need
for more innovative options for water interventions at the landscape scale, accounting for both green and blue water, as well
as a new focus on cross-scale interactions, feed-backs and risks for unwanted regime shifts in the agro-ecological landscape. 相似文献
490.