STREAM-CHANNEL INCISION FOLLOWING DRAINAGE-BASIN URBANIZATION1

ABSTRACT: Urbanization of a drainage basin results in pervasive hydrologic changes that in turn initiate long-term changes in stream channels. Increases in peak discharges and in durations of high flows result in either quasi-equilibrium channel expansion, where cross-section area increases in near-proportion to the discharge increase, or catastrophic channel incision, where changes occur far out of proportion to the discharge increases that initiated them. Field data and hydrologic modeling of rapidly urbanizing basins in King County, Washington, define conditions of flow, topography, geology, and channel roughness that identify streams susceptible to incision. Channel slope and geologic material are particularly critical; thus simple map overlays, nearly irrespective of contributing drainage area, provide a valuable planning tool for identification of susceptible terrain. Where such conditions exist, basal shear stress provides a quantifiable parameter for predicting likely problems, although knickpoints are typical in such settings and confound simple calculation of sediment-transport rates. Where urbanization proceeds in such areas, effective mitigation of the incision hazards requires a degree of stormwater control far in excess of standards typically applied to present development activity.     

Reviewing the carbon footprint analysis of hotels: Life Cycle Energy Analysis (LCEA) as a holistic method for carbon impact appraisal of tourist accommodation

This study discusses the potential for Life Cycle Assessment (LCA) to be utilized for the environmental assessment of tourism accommodation facilities, and their contribution to global carbon footprint. To demonstrate the viability of employing LCA in the hotel sector, its simplified derivative, Life Cycle Energy Analysis (LCEA), is applied to two tourism accommodation facilities in Poole, Dorset (UK) to quantify their CO₂ emissions. The results indicate that the reviewed hotels are less energy and carbon-intense than the tourism accommodation establishments reported in the literature. This may indirectly imply the continuous progress of hotel’s energy efficiency over time. The implications of the current energy use practices in the reviewed hotels are discussed and suggestions are made on how to further improve the energy performance and therefore cut the carbon footprint. Recommendations for hotel management and policy-making are developed to reduce the energy and carbon intensity of the hotel industry. A method for energy and carbon footprint analysis of outsourced laundries and breakfast services is also proposed.     

A time‐lagged investigation of the impact of coworker behavior on the effects of demographic dissimilarity

Although it is clear that coworker absenteeism, tardiness, and turnover can influence an employee's actions, scholars have yet to consider the impact of relational demography on the adoption of these behavioral norms. Inspired by social identity, situational strength, and attraction‐selection‐attrition theories, we proposed that individuals who differ from their coworkers in age, sex, or racioethnicity would feel threatened by their outnumbered status and subsequently motivated to be absent, tardy, or more likely to turnover. However, we expected coworker withdrawal behavior to moderate whether or not dissimilar personnel act on these desires. Results from hierarchical multilevel modeling analyses of data from 470 U.S. call center workers nested in 51 work groups revealed that racioethnic dissimilarity was positively related to time‐lagged changes in absenteeism and tardiness as well as heightened turnover likelihood. These effects emerged only among employees whose coworkers engaged in greater withdrawal behavior. Importantly, racioethnically dissimilar employees working in more permissive climates (i.e., those with high levels of coworker absenteeism, tardiness, or turnover) exhibited the greatest increases in absenteeism and tardiness over three months and had the highest supervisor‐rated turnover likelihood. Implications for diversity management are discussed. Copyright © 2015 John Wiley & Sons, Ltd.     

Development and Implementation of Strategic Frameworks for Air Quality Management in the UK and the European Community

The UK and the EC have recognized that the application of national and EC policies alone may not be cost effective in improving air quality in some areas, especially in traffic-congested urban centres and along major road transport corridors. Consequently both have introduced new strategic frameworksfor air quality management.This paper outlines and compares the UK National Air Quality Strategy (NAQS) and the EC approach, set out in the Air Quality Framework and Daughter Directives. Both frameworks shift responsibility for reviewing, assessing and managing air quality on to local authorities. The UK considers the NAQS will provide the principal means of carrying out its commitments under the new EC framework.Local authorities in the UK have begun the review and assessment phase of the NAQS. This paper examines the support that central government has had to provide to local authorities to ensure the NAQS will be effective. It offers insights into what other Member States are likely to face when implementing their interpretation of the EC air quality management framework. The paper highlights that many UK local authorities lacked even basic air quality management capabilities when the NAQS was being formulated. Consequently the UK Government has had to expand the national pollution monitoring networks (this was achieved primarily by affiliating the growing number of local authority funded sites), commission new detailed urban emissions inventories, and develop and validate a suite of air quality dispersion models. Training events in air quality assessment techniques have had to be offered and many detailed guidance notes issued to ensure an appropriate and consistent interpretation of the NAQS. Some government initiatives to support the implementation of the NAQS suffered delays which initially caused some unnecessary uncertainties and inconsistencies amongst local authorities conducting their review and assessment of air quality. This points to the importance of the Governmentensuring that the support for the management phase of the NAQS will be in place in time. This includes providing additional pollution-control powers and reformulating transport and planning policies in order to integrate air quality management more fully.     

Maximizing returns on mentoring: factors affecting subsequent protégé performance

This study examined the effects of mentor success, relationship duration, and the amount of mentoring received on protégés' performance after the supervisory mentoring relationship had ended. Data collected from former protégés paired with objective measures of performance indicated that a mentor's success moderated the impact of mentoring functions received on subsequent protégé success. Additionally, the strength of these relationships depended on the length of the mentoring relationship. The present study suggests more emphasis should be placed on the capabilities of the mentor. Copyright © 2006 John Wiley & Sons, Ltd.     

Demography and disappearing merchandise: How older workforces influence retail shrinkage

Prior research on retail shrinkage has taken a largely individual‐level approach to theorizing about why it occurs, showing that older employees are less prone to theft and more vigilant in preventing customer shoplifting than younger personnel. However, given the influence of organizational contexts on organizational behavior, theorizing about shrinkage may be enhanced by the consideration of business‐unit level contextual variables. The present study addressed this concern by examining the relationship between store‐level age composition, whistle‐blowing (WB) climate, and shrinkage in 726 retail stores. Results indicated that the negative mean age–shrinkage relationship was stronger when there was less age diversity or a climate more supportive of WB. Moreover, the negative WB climate–shrinkage linkage was stronger when the mean age was higher. Copyright © 2011 John Wiley & Sons, Ltd.     

A molecular genetic analysis of social structure, dispersal, and interpack relationships of the African wild dog (Lycaon pictus )

The African wild dog is a highly social, pack-living predator of the African woodland and savannah. The archetypal wild dog pack consists of a single dominant breeding pair, their offspring, and non-breeding adults who are either offspring or siblings of one of the breeding pair. Non-breeding adults cooperate in hunting, provisioning and the protection of young. From these observations follows the prediction that the genetic structure of wild dogs packs should resemble that of a multigenerational family, with all same-sexed adults and offspring within a pack related as sibs or half-sibs. Additionally, a higher kinship between females from neighboring packs should be evident if females tend to have small dispersal distances relative to males. We test these predictions through analysis of mitochondrial DNA control region sequences and 14 microsatellite loci in nine wild dog packs from Kruger National Park, Republic of South Africa. We show that as predicted, African wild dog packs generally consist of an unrelated alpha male and female, subdominant close relatives, and offspring of the breeding pair. Sub-dominant wild dogs occasionally reproduce but their offspring rarely survive to 1 year of age. Relatedness influences the timing and location of dispersal events as dispersal events frequently coincide with a change in pack dominance hierarchy and dispersers often move to areas with a high proportion of close relatives. Received: 22 February 1996 / Accepted after revision: 16 November 1996     

Aphid population response to agricultural landscape change: A spatially explicit,individual-based model

A spatially explicit individual-based simulation model has been developed to represent aphid population dynamics in agricultural landscapes. The application of the model to Rhopalosiphum padi (L.) population dynamics is detailed, including an outline of the construction of the model, its parameterisation and validation. Over time, the aphids interact with the landscape and with one another. The landscape is modified by varying a simple pesticide regime, and the multi-scale spatial and temporal implications for a population of aphids is analysed. The results show that a spatial modelling approach that considers the effects on the individual of landscape properties and factors such as wind speed and wind direction provides novel insight into aphid population dynamics both spatially and temporally. This forms the basis for the development of further simulation models that can be used to analyse how changes in landscape structure impact upon important species distributions and population dynamics.     

Principal biogeochemical factors affecting the speciation and transport of mercury through the terrestrial environment

It is increasingly becoming known that mercury transport and speciation in the terrestrial environment play major roles in methyl-mercury bioaccumulation potential in surface water. This review discusses the principal biogeochemical reactions affecting the transport and speciation of mercury in the terrestrial watershed. The issues presented are mercury-ligand formation, mercury adsorption/desorption, and elemental mercury reduction and volatilization. In terrestrial environments, OH-, Cl- and S- ions have the largest influence on ligand formation. Under oxidized surface soil conditions Hg(OH)2, HgCl2, HgOH+, HgS, and Hg0 are the predominant inorganic mercury forms. In reduced environments, common mercury forms are HgSH+, HgOHSH, and HgClSH. Many of these mercury forms are further bound to organic and inorganic ligands. Mercury adsorption to mineral and organic surfaces is mainly dictated by two factors: pH and dissolved ions. An increase in Cl- concentration and a decrease in pH can, together or separately, decrease mercury adsorption. Clay and organic soils have the highest capability of adsorbing mercury. Important parameters that increase abiotic inorganic mercury reduction are availability of electron donors, low redox potential, and sunlight intensity. Primary factors that increase volatilization are soil permeability and temperature. A decrease in mercury adsorption and an increase in soil moisture will also increase volatilization. The effect of climate on biogeochemical reactions in the terrestrial watershed indicates mercury speciation and transport to receiving water will vary on a regional basis.