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781.
We draw on the economic, corporate governance, and family business literatures to explain why the effects of family on family firms makes this governance form theoretically distinct from those of public and private non‐family firms. Our thesis is that parental altruism, when combined with private ownership and owner‐management, influences the ability of the firm's owner‐manager to exercise self‐control, which, in turn, can expose some family firms to conflicts rooted in the agency threats of moral hazard, hold‐up, and adverse selection. We then discuss why some other family firms are able to minimize these dark side threats and thereby attain altruism's brighter side. Finally, we discuss how altruism's influence changes over time as ownership becomes dispersed among family members and across generations. Copyright © 2005 John Wiley & Sons, Ltd.  相似文献   
782.
The current study used Mintzberg's (1983) conceptualization of political will and political skill to evaluate the predictors and consequences of political behavior at work. As elements of political will, we hypothesized that need for achievement and intrinsic motivation would predict the use of political behavior at work. Furthermore, we argued that political skill would moderate the relationship between political behavior and emotional labor. Data gathered from employees (N = 193) representing a wide array of organizations substantiated the proposed relationships. Specifically, need for achievement and intrinsic motivation were positively associated with political behavior. In turn, those opting to employ political behavior at work experienced a higher degree of emotional labor, but this relationship was found to operate differently at low and high levels of political skill. Specifically, emotional labor was a consequence of political behavior for those low in political skill, but emotional labor reactions from political behavior were neutralized for individuals high in political skill. Implications of these results, strengths and limitations, and directions for future research are discussed. Copyright © 2005 John Wiley & Sons, Ltd.  相似文献   
783.
Soil respiration is a large C flux which is of primary importance in determining C sequestration. Here we ask how it is altered by atmospheric CO2 concentration and N additions. Swards of Lolium perenne L. were grown in a Eutric cambisol under controlled conditions with and without the addition of 200 kg NO? 3 ?N ha?1, at either 350 ppm or 700 ppm CO2, for 3 months. Soil respiration and net canopy photosynthesis were both increased by added N and elevated CO2, but soil respiration increased proportionately less than fixation by photosynthesis. Thus, both elevated CO2 and N appeared to increase potential C sequestration, although adding N at elevated CO2 reduced the C sequestered as a proportion of that fixed relative to elevated CO2 alone. Across all treatments below-ground respiratory C losses were predicted by root biomass, but not by soil solution C and N concentrations. Specific root-dependent respiration was increased by elevated CO2, such that below-ground respiration per unit biomass and per unit plant N was increased.  相似文献   
784.
Critical N loads for ombrotrophic bogs, which often contain rare and N-sensitive plants (especially those in lower plant groups: lichens, mosses and liverworts), are based on very few experimental data from measured, low background N deposition areas. Additionally the relative effects of reduced versus oxidised N are largely unknown. This paper describes an automated field exposure system (30 km S. of Edinburgh, Scotland) for treating ombrotrophic bog vegetation with fine droplets of oxidised N (NaNO3) and reduced N (NH4Cl). Whim Moss exists in an area of low ambient N deposition (ca. 8 kg N ha?1 y?1), the sources and quantification of which are described. The wet N treatment system is run continuously, and is controlled/activated by wind speed and rainfall to provide a unique simulation of “real worl” treatment patterns (no rain=no treatment). Simulated precipitation is supplied at ionic concentrations below 4 mM in rainwater collected on site. Treatments provide a replicated dose response to 16, 32 and 64 kg N ha?1 y?1 adjusted for ambient deposition (8 kg N ha?1 y?1). The 16 and 64 kg N ha?1 y?1 are duplicated with a P+K supplement. Baseline soil chemistry and foliar nutrient status was established for all 44 plots for Calluna vulgaris, Sphagnum capillifolium, Hypnum jutlandicum and Cladonia portentosa.  相似文献   
785.
Providing an accurate estimate of the dry component of N deposition to low N background, semi-natural habitats, such as bogs and upland moors dominated by Calluna vulgaris is difficult, but essential to relate nitrogen deposition to effects in these communities. To quantify the effects of NH3 inputs to moorland vegetation growing on a bog at a field scale, a field release NH3 fumigation system was established at Whim Moss (Scottish Borders) in 2002. Gaseous NH3 from a line source was released along of a 60 m transect, when meteorological conditions (wind speed >2.5 m s?1 and wind direction in the sector 180–215°) were met, thereby providing a profile of decreasing NH3 concentration with distance from the source. In a complementary study, using a NH3 flux chamber system, the relationships between NH3 concentrations and cuticular resistances were quantified for a range of NH3 concentrations and micrometeorological conditions for moorland vegetation. Cuticular resistances increased with NH3 concentration from 11 s m?1 at 3.0 μg m?3 to 30 s m?1 at 30 μg m?3. The NH3 concentration data and the concentration-dependent canopy resistance are used to calculate NH3 deposition taking into account leaf surface wetness. The implications of using an NH3 concentration-dependent cuticular resistance and the importance for refining critical loads are discussed.  相似文献   
786.
A field ammonia (NH3) release experiment and open top chambers containing moorland monoliths continuously fumigated with NH3 or sprayed with NH4Cl were used to assess the potential for using δ15N values in determining the area of influence around a point NH3 emission source. δ15N values are being increasingly used as environmental tracers and we tested the hypothesis that the δ15N signal from an NH3 emission source is observable in nearby vegetation. Using modified monitoring devices, atmospheric NH3 concentrations were found to decrease with distance from source, with δ15N values also reflecting this trend, producing a signal shift with changing concentration. Open top chamber studies of δ15N values of Calluna vulgaris (L.) Hull indicated a correlation with deposition treatments in current year shoots. Analysis of Calluna shoots from the NH3 release showed a similar trend of δ15N enrichment. Significant linear correlations between δ15N and percent N in plant material were found, both in the controlled conditions of the open top chambers and at the NH3 release site, illustrating the possible use of this technique in N deposition biomonitoring.  相似文献   
787.
The results from three long-term field manipulation studies of the impacts of increased nitrogen deposition (0–120 kg N ha?1 yr?1) on lowland and upland heathlands in the UK were compared, to test if common responses are observed. Consistent increases in Calluna foliar N content and decreases in litter C:N ratios were found across all sites, while increases in N leaching were not observed at any site over the range 0–80 kg ha?1 yr?1. However, the response of Calluna biomass did vary between sites, possibly reflecting site differences in nutrient status and management histories. Five versions of a simulation model of heathland responses to N were developed, each reflecting different assumptions about the fate and turnover of soil N. Model outputs supported the deduction from mass balance calculations at two of the field sites that N additions have resulted in an increase in immobilisation; the latter was needed to prevent the model overestimating measured N leaching. However, this version of the model significantly underestimated Calluna biomass. Model versions, which included uptake of organic N by Callunaand re-mobilisation of N from the soil organic store provided some improvement in the fit between modelled and field biomass data, but re-mobilisation also led to an overestimation of N leaching. Quantification of these processes and their response to increased N deposition are therefore critical to interpreting experimental data and predicting the long-term impacts of atmospheric deposition on heathlands and moorlands.  相似文献   
788.
Model estimates of NOy and NHx deposition across Britain for 1996 (5 km square resolution) were applied as explanatory variables to account for national-scale, fine-grained changes in plant species composition between 1990 and 1998. Plant species data were recorded from up to 27 fixed plots located within a stratified random sample of 596 1 km2. The response variable was a cover-weighted Ellenberg fertility score for each plot. Analyses were carried out separately for woodlands, semi-natural grasslands and heaths/bogs. Most of the variation in the botanical response variable occurred between plots within squares and so could not be explained by the model deposition data. NHx deposition estimates accounted for significant, but small components of between 1 km2 variation in the change in Ellenberg score in grasslands (5.6%) and heath/bogs (9.8%) but not woodlands. NOy deposition estimates were not significantly associated with vegetation change. Linear models provided the best fit and the slope of the relationship was lower for heath/bogs than grasslands. Further signal attribution at sub-kilometre square scales requires the development of fine-grained models of N deposition that can be generalised across regional sampling domains.  相似文献   
789.
In 1995, the U.S. Environmental Protection Agency (US EPA) initiated the Brownfields Program to help local governments clean up and reuse hundreds of thousands of contaminated former factories and transportation and other commercial sites in cities and industrialized suburbs. By the end of 2002, the Brownfields Program had distributed grants of about $200,000 each to 436 local governments. Program grants have diffused through federal, state, regional, and local levels of government and private and not‐for profit organizations, and have reached into economically distressed neighborhoods. As expected, grant recipients disproportionately had a legacy of contaminated industrial sites and relatively large African American and/or Latino populations. But abandoned factories and environmental justice concerns do not completely explain the geographical distribution of recipients. Award winners tended to be larger cities with more capacity to compete for grants and were likely to be connected to sources of information about the grant opportunity and to decision makers. With a few exceptions, recipients consider the program to be highly successful at stimulating entrepreneurs to remediate and redevelop sites and, sometimes, surrounding neighborhoods. © 2005 Wiley Periodicals, Inc.  相似文献   
790.
This article discusses creating a sustainably protective engineered and human management system in perpetuity for sites with long‐lived radiological and chemical hazards. This is essential at this time because the federal government is evaluating its property as assets and attempting to reduce its holdings, while seeking to assure that health and ecosystems are not put at risk. To assist those who have a stake in the remediation, management, and stewardship of these and analogous privately owned sites, this article discusses current end‐state planning by reviewing the federal government's accelerated efforts to reduce its footprint and how those efforts relate to sustainability. The article also provides a list of questions organized around six elements of risk management and primary, secondary, and tertiary disease and injury prevention. Throughout the article, the U.S. Department of Energy (DOE) is used as an example of an organization that seeks to reduce its footprint, manage its budget, and be a steward of the sites that it is responsible for. However, the approach and questions are appropriate for land controlled by the Department of Defense (DOD), the General Services Administration (GSA), and other public and private owners of sites with residual contamination. © 2005 Wiley Periodicals, Inc.  相似文献   
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