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381.
In a field experiment with 517 job applicants, the processes underlying the formation of procedural justice judgments were investigated. It was hypothesized that procedural justice judgments may be based not only on content information (e.g., “What are fair aspects of the selection procedure?”), but also on the felt ease or difficulty with which this content information can be retrieved from memory (ease‐of‐retrieval; e.g., “How easily can I recall fair aspects of the selection procedure?”). Evaluations of the company's online application procedure show that job candidates based procedural justice judgments on content information or on ease‐of‐retrieval, depending on their uncertainty regarding the online application procedure as well as their prior experiences with online applications. Specifically, experienced applicants who felt certain based their judgments on ease‐of‐retrieval, whereas all other applicants based their judgments on content information. Implications for research on the formation of justice judgments as well as practical applications are discussed. Copyright © 2010 John Wiley & Sons, Ltd.  相似文献   
382.
Flood-pulse and riverscape dynamics in a braided glacial river   总被引:1,自引:0,他引:1  
Malard F  Uehlinger U  Zah R  Tockner K 《Ecology》2006,87(3):704-716
River ecosystems are increasingly viewed as dynamic riverscapes; their extent, composition, and configuration vary in response to the pulsing of discharge. Although compositional and configurational shifts in riverscapes are thought to control ecosystem processes and biodiversity, attempts to quantify riverscape dynamics of braided rivers are scarce. We measured monthly changes in the length, spatial arrangement, and age distribution of clear (groundwater-fed) and turbid-water (glacial-fed) channels during two annual cycles in a braided glacial river. Biological data from concurrent studies were used to assess the effects of seasonal changes in the size and pattern of the riverscape on local zoobenthic density, standing crop of epilithic algae, and spatiotemporal distribution of the hyporheos. The hydrological processes involved in the expansion-contraction cycle of the riverscape resulted in a complex, albeit predictable, pattern of change in the proportion and spatial arrangement of clear and turbid channels. On average, 30% of the riverscape was renewed at monthly intervals. Surface hydrological connectivity and the length of turbid channels increased logarithmically with increasing discharge. The length of clear channels increased up to a threshold discharge of 1.5 m3/s, above which surface flooding resulted in the contraction and fragmentation of clear water bodies. Turbid channels exhibited a unimodal age distribution, whereas clear channels had two cohorts that appeared during the expansion and contraction phases. The renewal pattern and configuration of the riverscape changed little between years despite differences in discharge and the occurrence of several rainfall-induced spates. The density of benthic invertebrate communities in the main channel decreased with increasing size of aquatic habitats indicating that local zoobenthic density was affected by dilution-concentration effects. The disproportionate increase in the proportion of glacial-fed habitats during summer high flows limited the standing crop of epilithic algae in this braided river. The spatial arrangement of inhospitable glacial-fed habitats probably impeded the colonization of newly created suitable habitats by invertebrates with poor dispersal capacities. Quantification of riverscape dynamics is critical to understanding how changes in size, composition, and configuration of braided rivers affect biodiversity, bioproduction, and ecosystem processes.  相似文献   
383.
Young Populus tremula, Salix viminalis, Betula pendula and Picea abies trees were grown together in large open-top chambers. The treatments were: without or with (Cu/Zn/Cd/Pb=640/3000/10/90 mg kg-1) metal contamination in the topsoil, irrigation pH 3.5 or 5.5, and acidic or calcareous subsoil. Growth, metal allocation to foliage and wood, as well as leaf gas exchange were measured. Biomass was reduced in P. tremula and B. pendula by the metal-contaminated topsoil relative to uncontaminated topsoil, whereas in P. tremula photosynthesis and transpiration were decreased. These effects were related to the elevated foliar Zn accumulation in P. tremula. S. viminalis showed a significant reduction in growth and an increased Zn and Cd accumulation on acidic vs. calcareous subsoil. Acidic irrigation produced only a few significant effects. P. abies showed the lowest metal uptake and no growth response to metal contamination.  相似文献   
384.
A comparison of the concentration of the total suspended particulate (TSP) matter measured by the tapered element oscillating microbalance (TEOM) monitor and the isokinetic TSP samplers developed at the University of Illinois was carried out in several types of confinement livestock buildings. In a majority of the measurements done, the dust concentration measured by the TEOM monitor was lower than the University of Illinois at Urbana-Champaign (UIUC) isokinetic TSP sampler; the TEOM monitor tended to underestimate the total dust concentration by as much as 54%. The difference in measurements can be attributed to the sampling efficiency of the TEOM monitor sampling head and the loss of some semivolatile compounds and particle-bound water because of heating of the TEOM monitor sampling stream to 50 degrees C. Although several articles in the literature supported the latter argument, this study did not investigate the effect of heating the sampling stream or the effect of moisture on the relative difference in dust concentration measurements. The model that best describes the relationship between the two methods was site specific, that is, the linear regression model was applicable only to four of the sites monitored. The measured total dust concentration in livestock buildings range from approximately 300 to 4000 microg/m3; a higher correlation coefficient between TEOM-TSP and UIUC-TSP monitors was obtained in swine facilities than those obtained in a laying facility.  相似文献   
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