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Correlation estimates from a meta‐analysis of 108 studies including 126 independent samples and nearly 70 000 participants were used to test multiple path models of the antecedents of militant and nonmilitant union participation. Variables moderating the relationship between union commitment and participation were examined. The magnitude of the relationship between commitment and militant participation was moderated by status‐based group membership (i.e., white collar versus blue collar), supporting a contingency model of union participation. Results updated and further developed an integrative model of union participation. Copyright © 2010 John Wiley & Sons, Ltd.  相似文献   
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Environmental Science and Pollution Research - National Environmental Quality Standards (EQS) for zinc used for the assessment of ecological status in freshwaters have been shown to vary by over...  相似文献   
996.
We employed qualitative methods to explore how conflict over water collection and use impacts women, and the role that women play in water management and conflict resolution in Marsabit, Kenya. Conflicts between domestic and livestock water led to insufficient water for domestic use and intra-household conflict. Women’s contributions to water management were valued, especially through informal initiatives, though involvement in statutory water management committees was not culturally appropriate. Promoting culturally appropriate ways to involve women in water management, rather than merely increasing the percentage of women on water committee, may reduce conflicts and increase women’s access to domestic water supplies.  相似文献   
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Little is known about the impact of agricultural legacy on subsurface biogeochemical processes in the years following restoration of riparian wetlands (WLs). More knowledge is also needed on the relative importance of seasons, precipitation events, and inputs of water and nutrients driving nitrogen (N), phosphorus (P), sulfur (S), and greenhouse gas (GHG) (N2O, CO2, CH4) dynamics in these systems. This investigation of a riparian zone comprising a restored WL area and a nonrestored well‐drained alluvium (AL) area in the United States Midwest revealed that despite successful hydrological restoration a decade earlier, biogeochemical conditions in the WL area remained less anoxic than in natural WLs, and not significantly different from those in the AL area. No significant differences in N, P, S, and C compound concentrations or fluxes were observed between the AL and WL areas. Over the duration of the study, nitrate (NO3?) and soluble reactive phosphorus appeared to be primarily driven by hillslope contributions. Ammonium (NH4+), sulfate (SO42?), and CO2 responded strongly to seasonal changes in biogeochemical conditions in the riparian zone, while N2O and CH4 fluxes were most influenced by large rewetting events. Overall, our results challenge overly simplistic assumptions derived from direct interpretation of redox thermodynamics, and show complex patterns of solutes and GHGs at the riparian zone scale.  相似文献   
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The link between sediment contamination and flooding is not well established, since flooding may exacerbate problems by spreading pollutants throughout the floodplain, or alternatively may dilute contaminants in source areas. To determine the substance of such relationships, the pattern of sediment contamination was examined in a small Idaho town following flooding in 1996. Four heavy metals were tested, nickel, chromium, zinc and copper, in 97 soil samples obtained from sites across the floodplain of the St. Joe River. Flood history and land-uses at each sample site were noted. Results showed that contamination levels generally were not high, with flood areas having lower concentrations than non-flood areas. A stronger relationship could be argued for land-use, with higher concentrations of contamination associated with some industrial sites. High levels of contamination were also found in several samples taken from recreational areas. Further research looking at the potential sources of contamination in relation to characteristics of the flood hydrology would seem pertinent.  相似文献   
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Investment into reproduction is influenced by multiple factors and varies substantially between males and females. Theory predicts that males should adjust their ejaculate size or quality in response to variation in female experience or phenotypic quality. In addition, sperm investment by males may also be influenced by their own status and experience. Although such adjustments of male ejaculate size can impact reproductive success (via fertilization success), fitness returns from male sperm investment may be influenced (either limited or facilitated) by the level of maternal investment. To test this hypothesis, we conducted an experiment that simultaneously evaluated the effect of paternal and maternal experience (which incorporates mating status, age, body size, and other related variables) on paternal sperm investment and maternal reproductive allocation in the lizard Anolis sagrei. During staged mating trials, experienced males were more likely to copulate with females, but these individuals were less likely to transfer sperm during mating than were naïve individuals. Maternal experience had no impact on these mating behaviors. In contrast to expectations, experience and phenotypic quality (of both sexes) had no impact on male ejaculate size or quality (proportion of live sperm) or on maternal reproductive investment (in terms of egg size and yolk steroids). These findings were intriguing given the mating system and past evidence for differential maternal investment in relation to sire quality in A. sagrei. The results found in this study highlight the complexity of reproductive investment patterns, and we urge caution when applying general conclusions across populations or taxa.  相似文献   
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