ERD of Residual TCE DNAPL Achieving Nondetect from a Single Injection of Food‐Grade Waste

Residual dense nonaqueous phase liquid (DNAPL) composed of trichloroethene (TCE) was identified in a deeper interval of an overburden groundwater system at a manufacturing facility located in northern New England. Site hydrostratigraphy is characterized by two laterally continuous and transmissive zones consisting of fully‐saturated fine sand with silt and clay. The primary DNAPL source was identified as a former dry well with secondary contributions from a proximal aboveground TCE storage tank. A single additive‐injection mobilization in 2001 utilizing a food‐grade injectate formulated with waste dairy product and inactive yeast enhanced residual TCE DNAPL destruction in situ by stimulating biotic reductive dechlorination. The baseline TCE concentration was detected up to 97,400 μg/L in the deeper interval of the overburden groundwater system, and enhanced reductive dechlorination (ERD) achieved >99 percent reduction in TCE concentrations in groundwater over nine years with no evidence of sustained rebound. TCE concentrations have remained nondetect below 2.0 μg/L for the last five consecutive sampling rounds between 2013 and 2015. ERD utilizing a food‐grade injectate is a green remediation technology that has destroyed residual DNAPL at the site and achieved similar results at other residual DNAPL sites during both pilot‐ and full‐scale applications. ©2016 Wiley Periodicals, Inc.     

Unraveling the impact of workforce age diversity on labor productivity: The moderating role of firm size and job security

Previous literature has suggested both positive and negative effects of age diversity on labor productivity: positive because of the potential knowledge complementarities between employees of different ages and negative because of the age‐related value differences that might reduce cohesion and cooperation, hampering firm performance. Using a Belgian sample of 5892 organizational observations (2008–2011), we unraveled these countervailing effects in two ways. First, we built on prior studies to suggest that the effect of age diversity depends on the particular shape of the age distribution: positive when it is heterogeneous (i.e., variety) and negative when it is polarized (i.e., polarization). This was supported by our findings. Second, we explored the moderating impact of two contextual contingencies, firm size and job security. As expected, the positive effect of age variety is reinforced in large firms and in firms where job security is high. Although firm size also emphasizes the negative effect of age polarization on productivity, job security, unexpectedly, does not moderate this relationship. Our study offers a valuable contribution to the literature as it reveals the boundary conditions of the competing implications of age diversity and, thus, allows one to account for the inconclusive findings reported in previous literature. Copyright © 2015 John Wiley & Sons, Ltd.     

A new look at the psychological contract during organizational socialization: The role of newcomers' obligations at entry

Previous studies have demonstrated that the psychological contract is largely shaped during socialization. This study adopts a complementary perspective and analyzes how the psychological contract at the start of employment shapes the subsequent socialization process. Drawing upon social exchange theory, we propose that newcomers with a higher sense of their personal obligations at entry will perceive orientation training as more useful and develop better relationships with their supervisors and peers, which in turn will facilitate their work adjustment. Results of a longitudinal survey on a sample of 144 recruits from a European Army show that newcomers with a higher initial sense of their employee obligations toward their employer report higher perceived training utility, higher leader–member exchange (LMX) with their instructors, and higher team–member exchange (TMX) with their platoon peers. Moreover, perceived training utility and LMX predict the fulfillment of employers' obligations; and training utility predicts the level of newcomers' employee obligations. Finally, training utility, LMX, and TMX predict some of three indicators of newcomers' adjustment, namely, role clarity (training utility and LMX), group integration (TMX), and organizational values understanding (training utility). These results highlight how newcomers' obligations at the start of employment contribute to the social exchange dynamic underlying organizational socialization. Copyright © 2015 John Wiley & Sons, Ltd.     

Land management in rural Burkina Faso: the role of socio‐cultural and institutional factors

Farmers in the Sahel have been acknowledged for reclaiming degraded lands and improving food security by ingeniously modifying traditional agroforestry, water, and soil management practices. Despite the advantages offered by this range of farming techniques, their adoption rate is influenced by several factors. Using multivariate probit models and a correlation coefficient, this article examines the factors influencing the adoption of five land management practices based on 220 household and 40 farm surveys in four adjacent rural communities in southern Burkina Faso. The model results indicate that household labor force, education of household head, land tenure security, livestock holding, and membership in farmers’ groups influence the adoption of zaï practice, composting, improved fallow, stone bunds, and live hedges. However, two of the surveyed factors ‐ number of farms and visit by agricultural extension staff during the 12 months prior to the survey ‐ were not significant. Furthermore, a significant correlation was found between different land management practices, e.g., the decision to practice zaï is significantly linked to that of live hedges and composting. Zaï practice and stone bunds are considered labor intensive, which explains their significant correlations with household labor force at the 1% and 5% levels of significance, respectively.     

Bird Species Assemblages as Indicators of Biological Integrity in Great Basin Rangeland

The study evaluates the potential for bird species assemblages to serve as indicators of biological integrity of rangelands in the Great Basin in much the same way that fish and invertebrate assemblages have been used as indicators in aquatic environments. Our approach was to identify metrics of the bird community using relatively simple sampling methods that reflect the degree of rangeland degradation and are consistent over a variety of vegetation types and geographic areas. We conducted the study in three range types (i.e., potential natural plant community types) in each of two widely separated areas of the Great Basin: south-eastern Idaho (sagebrush steppe range types) and west-central Utah (salt-desert shrub range types). Sites were selected in each range type to represent three levels of grazing impact, and in Idaho included sites modified for crested wheatgrass production. Birds were sampled by point counts on 9 100-m radius plots at 250-m spacing on each of 20 sites in each area during the breeding season. In sagebrush-steppe, 964 individuals in 8 species of passerine birds were used in analyses. Five metrics were significantly related to impact class, both when analyzed within range type and when analyzed with all range types combined. Species richness, relative abundance of shrub obligate species, and relative abundance of Brewer's sparrow were generally lower for the higher impact classes, whereas the reverse was true for dominance by a single species and for relative abundance of horned larks. In contrast, total number of individuals did not differ significantly as a function of impact class. In salt-desert shrub, a total of 843 birds in 4 species were included in analyses, 98% of which were horned larks. None of the metrics identified above was significantly related to impact class. Two metrics for breeding birds in sagebrush steppe (species richness and dominance) showed little overlap between values for the extremes of impact class, and thus they have potential as indicators of biological integrity. However, the sensitivity of these metrics appears to be greatest at the high impact end of the spectrum, which suggests they may have limited utility in distinguishing between sites having light and moderate impact.     

An Exploratory Study of Meanings of Risk Control for Long Term and Acute Effect Occupational Health and Safety Risks in Small Business Construction Firms

A qualitative study of employers' and employees' meanings of occupational health and safety (OHS) risk control was conducted among a sample of small businesses engaged in the Australian construction industry. Two OHS risks relevant to the construction industry were selected for study. One risk (falls from height) represented an immediate consequence, whereas the other (occupational skin disease) represented a long-term health effect. Meanings of the sources and control for these risks were explored during in-depth interviews. Participants perceived the immediate effect, falls from height OHS risk, as being more important in their workplaces than the delayed effect, skin disease OHS risk. The risk of falls from height was perceived to be controllable but requiring a great deal of effort to prevent, whereas there was a fatalistic resignation to the risk of occupational skin disease. Meanings of risk control for both occupational skin disease and falls from height focused on individual rather than technological risk controls. Organizational barriers to the adoption of technological OHS risk controls in the construction industry were identified.     

EVALUATION OF RUNOFF,EROSION, AND PHOSPHORUS MODELING SYSTEM—SIMPLE1

ABSTRACT: The purpose of this study was to evaluate the performance of Spatially Integrated Models for Phosphorus Loading and Erosion (SIMPLE) in predicting runoff volume, sediment loss, and phosphorus loading from two watersheds. The modeling system was applied to the 334 ha QOD subwatershed, part of the Owl Run watershed, located in Fauquier County, Virginia, and to the 2240 ha watershed, Battle Branch, located in Delaware County, Oklahoma. Simulation runs were conducted at cell and field scales, and simulation results were compared with observed data. Runoff volume and dissolved phosphorus loading were measured at the Battle Branch watershed. Runoff volume, sediment yield, and total phosphorus loading were measured at the QOD site. SIMPLE tended to underestimate runoff volumes during the dormant period, from November to March. The comparison between observed and predicted dissolved phosphorus showed better correlation than for observed and predicted total phosphorus loading. Cell level simulations provided similar estimates of runoff volume and phosphorus loading when compared to field level simulations for both watersheds. However, observed sediment yields better compared with the values predicted from the cell level simulation when compared to field level simulation. Finally, results of model evaluation indicated that SIMPLE's predictive ability is acceptable for screening applications but not for site-specific quantitative predictions.     

Environmental space and barriers to local sustainability: Evidence from Edinburgh, Scotland

This paper steps into the minefield that is urban sustainability studies. It defends a rigorous definition of sustainable development called Environmental Space. This approach starts from the assumption that (1) there are limits to the biophysical capacity of the ecosystem and (2) that — within these limits — each individual has equal access rights to natural capital. On this basis, per capita sustainable consumption targets are calculated which can be (and are being) used as policy objectives. The paper explores how environmental space has influenced local sustainability politics in Edinburgh, Scotland. By doing so, it finds that environmental space targets are still far from being achieved. Reasons for this failure are investigated and Edinburgh's continued commitment to the material growth of her economy is identified as one key barrier. This point is illustrated through the investigation of recent policy decisions in Edinburgh which were justified as being necessary for growth, but which clearly contradict the aims of sustainable development.