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1.
What matters for work engagement? A diary study on resources and the benefits of selective optimization with compensation for state work engagement 下载免费PDF全文
This diary study addresses the benefits of employees' daily use of selective optimization with compensation (SOC) for state work engagement. We hypothesized that day‐level SOC not only directly fosters work engagement but that SOC also reveals its beneficial effects for work engagement in interaction with both external and internal resources. Specifically, we proposed SOC substitutes for job control, role clarity, and state of being recovered, thus helping employees manage low daily levels of these resources. We tested our hypotheses with a sample of 138 employees who completed two daily surveys over a total of 545 workdays. Results of multilevel analyses revealed that SOC benefits work engagement in both proposed ways. First, day‐level SOC was positively related to state work engagement. Additionally, day‐level role clarity and state of being recovered predicted state work engagement, but day‐level job control did not. Second, SOC benefitted state work engagement by offsetting low levels of role clarity and being recovered, and by boosting job control in their respective relationships with work engagement. The results suggest that by using SOC at work, employees can actively enhance their own work engagement on a given workday. This knowledge provides promising starting points for the development of interventions. 相似文献
2.
Under what conditions do critical events trigger large-scale public discussion and mobilisation, and can these lead to policy change? In a comparative study of nuclear energy policy after the Japanese Fukushima disaster in March 2011, a theory-development approach is adopted, mobilising data collected from national news agencies’ newswires, public surveys, legislation and parliamentary databases, and newspaper editorials in 12 established democracies between March 2011 and March 2013. The analysis suggests two main hypotheses that can guide future research: critical events are more likely to trigger policy change when intense (contentious) mobilisation from policy challengers aligns with the views of the general public, and is backed by major political allies; and critical events are more likely to trigger intense (contentious) mobilisation when policy challengers articulate their opposition around pre-existing policy debates on the issue and resort to pre-existing organisational and mobilisation resources. 相似文献
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4.
Norman Myers 《The Environmentalist》1992,12(1):15-27
Summary Tropical forests are being destroyed faster than ever, the rate having almost doubled during the 1980s. The main agent of deforestation now turns out to be the displaced peasant or landless farmer, sometimes known as the shifted cultivator; that group accounts for more forest loss than the combined impacts of the commercial logger, the cattle rancher and all other better known sources of deforestation. Yet, the over-riding target of conservation efforts remains the minor players in the forest's decline. All too little attention is directed towards the shifted cultivator, and next to nothing is done to address the problem which this group represents. Policy purviews need to be expanded to include the key factor of the shifted cultivator. In turn, it must determined what impels these people to abandon established farming areas in the countries concerned and to migrate into the forests. It appears that these people are driven by an array of forces: population growth, maldistribution of arable lands, inadequate rural infrastructure and lack of government attention to subsistence agriculture. In other words, the source problem is an amalgam of non-forestry factors, and conservationists will not achieve success in safeguarding the remaining forests unless they direct much more emphasis towards these root causes of deforestation.Dr Norman Myers is a consultant in environment and development, a member of this journal's Advisory Board and a regular contributor to the journal (seeThe Environmentalist,8(3), 187–208 and10(4), 243–256). 相似文献
5.
Biomonitoring dissolved heavy metals within estuaries,particularly at their upper reaches, frequently has to relyon several biomonitors; rarely a single species thrives allalong the salinity gradient. To properly do so, it must beestablished whether those biomonitors actually accumulateheavy metals alike. In this study, two brown seaweeds fromthe upper section of three NW Spain estuaries – the widely-known Fucus vesiculosus and the estuarine Fucusceranoides – were compared as metal biomonitors. Bothspecies were collected at five locations where they eithercoexist or live close to each other and their heavy metalcontent (Cu, Cr, Mn, Zn, Fe, Al) was measured. Analyseswere appropriately replicated for each species x locationcombination to allow a statistically reliable detection ofdifferences in bioaccumulation, with particular emphasis onthe magnitude of interspecific differences. The lack of significant differences for Cu, Mn, and Zncontents in F. ceranoides and F. vesiculosussupports the feasibility of their joint use to monitorthese metals along the estuaries. Conversely, F.ceranoides concentrated significantly higher levels of Cr,Fe, and Al than F. vesiculosus and hence combiningdata for both fucoids to monitor these elements seemsimpractical. The correlation of species differencestogether with a similar Al:Fe ratio in both weed tissue andsediment suggest that Cr, Fe, and Al tissue-burdens mightbe considerably biased by sediment retained on the surfaceof the weed. Parallel analyses of Al and/or Fe in seaweedsand sediments could serve to keep track of thisinterference and may help to combine data from both fucoidsfor monitoring elements like Cr. 相似文献
6.
Kelsey RH Scott GI Porter DE Thompson B Webster L 《Environmental monitoring and assessment》2003,81(1-3):337-348
Multiple Antibiotic Resistance (MAR) analysis and regression modeling techniques were used to identify surface water areas impacted by fecal pollution from human sources, and to determine the effects of land use on fecal pollution in Murrells Inlet, a small, urbanized, high-salinity estuary located between Myrtle Beach and Georgetown, South Carolina. MAR analysis was performed to identify areas in the estuary that are impacted by human-source fecal pollution. Additionally, regression analysis was performed to determine if an association exists between land use and fecal coliform densities over the ten-year period from 1989 to 1998. Land-use variables were derived using Geographic Information System (GIS) techniques and were used in the regression analysis.MAR analyses were conducted by comparing the frequency and patterns of antibiotic resistance found in Escherichia coli isolates derived from surface water samples and from sewage sources in the Murrells Inlet sewage collection system. The MAR results suggest that the majority of the fecal pollution detected in the Murrells Inlet estuary may be from non-human sources, including fecal coliforms isolated from areas in close proximity to high densities of active septic tanks.A MAR Index, which measures the frequency of antibiotic resistance, was calculated for each of twenty-three water samples and nine sewage samples. The antibiotic resistance pattern comparisons were performed using cluster analysis. Although the MAR indices indicated that several surface water sites had potential human-source contamination, the cluster analysis suggests that only one sampling site had MAR patterns that were similar to those found in the sewage samples. This site was in close proximity to several large pleasure boats as well as a sewage collection system lift station, but was not near areas with active septic tanks. The results of the regression analysis also suggest that sewage sources and rainfall runoff from urbanized areas may contribute to fecal pollution in the estuary. 相似文献
7.
生态学与经济学的合流 总被引:2,自引:0,他引:2
生态学家和经济学家在环境问题上各持己见,误解很深。近年来,生态学家和经济学家逐渐认识到了合作的重要性。但是,他们的合作一直磕磕碰碰。其中,最大的分歧在于如何合作才是最有效的。促进双方的沟通和理解可使经济学家更多地将环境问题纳入经济范畴,使生态学家探索运用经济手段解决环境问题的新思路。 相似文献
8.
Paula Muukkonen Helin Hartikainen Kirsti Lahti Asko Srkel Markku Puustinen Laura Alakukku 《Agriculture, ecosystems & environment》2007,120(2-4):299-306
No-tillage (NT) is a method adopted to reduce erosion and particulate phosphorus (P) load from arable land to watercourses. However, it has been found to increase the loss of dissolved P with surface runoff, but the reasons for that have rarely been examined in detail. The objective of the present study was to determine the chemical factors explaining this response by investigating the impact of NT on the type and distribution of P reserves as well as on organic carbon (C) in the 0–35 cm topsoil layer of clay soil profiles (Vertic Cambisols). Soil samples were taken from two experimental fields (Jokioinen and Aurajoki) at 0–5, 5–20 and 20–35 cm depths in conventionally tilled (CT) and non-tilled (for 4–5 years) plots. The plots had been cultivated and fertilized according to the common field practices in Finland (15–18 kg P and 100–128 kg N ha−1 year−1).Inorganic and organic P reserves characterized by a modified Chang and Jackson fractionation procedure were not significantly affected by the cultivation methods. However, in the uppermost soil layer (0–5 cm) in NT of the Jokioinen field, the labile P determined by water extraction (Pw) increased significantly, whereas the increase in P extracted with acid ammonium acetate (PAAC) remained statistically insignificant. The increase in labile P coincided with a significant increase in organic carbon (C), which supports the theory that competition between organic anions and phosphate for the same sorption sites on oxide surfaces will enhance the lability of soil P. In the Aurajoki field with distinct soil cracking, Pw and PAAC were not affected by NT in the uppermost soil layer, but they increased in the deepest soil layer (20–35 cm) concomitantly with an increase in Al-bound P and organic C. However, the increases were not statistically significant. In both fields, soil acidification due to the repeated application of N fertilizers at a shallow soil depth as well as the accumulation of organic C lowered pH of the uppermost soil layer in NT compared to the deeper soil layers. The results indicated that even short-term NT can increase the labile P in clay soil. However, further studies are needed to assess the long-term changes in lability of surface soil P and, consequently, the possible need for readjustment of the fertilization level in NT. 相似文献
9.
Catherine Potvin Petra Tschakert Frédéric Lebel Kate Kirby Hector Barrios Judith Bocariza Jaime Caisamo Leonel Caisamo Charianito Cansari Juan Casamá Maribel Casamá Laura Chamorra Nesar Dumasa Shira Goldenberg Villalaz Guainora Patrick Hayes Tim Moore Johana Ruíz 《Mitigation and Adaptation Strategies for Global Change》2007,12(8):1341-1362
This paper is part of a two-year study to investigate the feasibility of initiating a Clean Development Mechanism (CDM) project
in an indigenous community of Eastern Panamá, Ipetí-Emberá. We use participatory mapping and matrices as well as household
surveys to develop a land-use/land-cover baseline scenario and examine the role of local participation in assessing land-use
change. In Ipetí, land-use change has not occurred in a linear way over the last decades, and our data unveils socio-economic
factors as potential key drivers of change. The concordance that we observed between geographic information and individual
and collective perceptions of land-use change substantiates the possibility of using local knowledge in the establishment
of baseline data for CDM projects. Our calculations suggest that the total carbon (C) stocks in the Tierra Colectiva (TC) of Ipetí-Emberá in 2004 represents a 47% reduction from the estimated C stock at the onset of settlement in the early
1970’s. Results from the participatory assessments predict that, in 2024 and in absence of a CDM project, the C stocks will
decline from 301,859 t C in 2004 to 155,730 t C, which constitutes a reduction of 52%. The scenario with CDM estimates C stocks
of 305,853 t C for 2024, a value slightly superior to the 2004 value. In the TC there is ground to believe that cattle ranching
is likely to become an ever more important activity as the population is young and growing and cannot easily move elsewhere.
Forests tend to be cleared for cultivation while pastures are established on short fallows. Our baseline scenario underlines
the potential for a CDM project to make a significant difference in the future C stocks of this landscape. 相似文献
10.
Norman Myers 《The Environmentalist》1996,16(1):37-47
A large proportion of existing species — possibly half, conceivably even more — may be lost within the foreseeable future. But this may not prove to be the most consequential outcome of the current biodiversity crisis. More significant could be the disruption and degradation of several basic processes of evolution. It appears likely that for mass extinction episodes (MEEs) in the geological past, the recovery period usually lasted at least five million years. Because of certain unique features of the present MEE — notably the near elimination of biomes such as tropical forests, wetlands and coral reefs, which have served as powerhouses of evolution in the past — the bounce-back phase could extend several times longer than five million years. Among distinctive features of future evolution could be; in the short term, homogenization of biotas, a proliferation of opportunistic species, an outburst of speciation among particular taxa, and a pest-and-weed ecology; and, in the long term, a decline of biodisparity, the elimination of megavertebrates, an end to speciation among large vertebrates, and multiple constraints on origination, innovation and adaptive radiation. These disruptive phenomena would rank among the most prominent departures in the entire course of evolution. Full knowledge and understanding of what may characterize future evolution remains largely a black hole of research. As a consequence, conservation policies fail to reflect a further problem of the biodiversity prospect, perhaps exceeding the better recognized problem of the mass extinction of species.Professor Norman Myers is an Editorial Board member and regular contributor toThe Environmentalist. He is an Honorary Visiting Fellow at Green College, Oxford. This paper is a greatly expanded version of a preliminary probing in a popular magazine a decade ago (Myers, 1985). It has been prompted by a major international conference organized by the US National Academy of Sciences, scheduled for late 1996. 相似文献