Measurement of particulate aliphatic and polynuclear aromatic hydrocarbons in Santiago de Chile: source reconciliation and evaluation of sampling artifacts

Using a novel sampler, particulate organic compounds were collected in Santiago de Chile from June 9 to August 10, 1997. This sampler consists of a diffusion denuder to remove gas-phase organics prior to particle collection, a Teflon filter, and a PUF cartridge downstream of the filter. PAHs and n-alkanes were measured using gas chromatography/mass spectrometry analysis. Volatilization of particles collected on the Teflon filter varied from 15 to 85% for both n-alkanes and PAHs, with strong dependence on molecular weight. The relative distribution of n-alkanes and the values of molecular diagnostic ratios, such as Carbon preference index, indicated a mixed origin with strong anthropogenic input. Indeed, CPI values ranged from 0.66 to 1.96 (for the whole range of n-alkanes). The percent contribution of leaf “wax” n-alkanes (4.55–20.83%) indicated the low contribution of biogenic sources. In addition, the distribution pattern of PAHs was characteristic of anthropogenic emissions. The dominant contribution of combustion-related PAHs (CPAHs), 74–84%, indicated that vehicular emissions was the major source of PAHs.     

Relationships Between Landscape Characteristics and Nonpoint Source Pollution Inputs to Coastal Estuaries

The model can help in examining the relative sensitivity of water-quality variables to alterations in land use made at varying distances from the stream channel. The model also shows the importance of streamside management zones, which are key to maintenance of stream water quality. The linkage model can be considered a first step in the integration of GIS and ecological models. The model can then be used by local and regional land managers in the formulation of plans for watershed-level management.     

A meta‐analytic comparison of self‐reported and other‐reported organizational citizenship behavior

Given the common use of self‐ratings and other‐ratings (e.g., supervisor or coworker) of organizational citizenship behavior (OCB), the purpose of this meta‐analysis was to evaluate the extent to which these rating sources provide comparable information. The current study's results provided three important lines of evidence supporting the use and construct‐related validity of self‐rated OCB. The meta‐analysis of mean differences demonstrated that the mean difference in OCB ratings is actually quite small between self‐ and other‐raters. Importantly, the difference between self‐ and other‐raters was influenced by neither the response scale (i.e., agreement vs. frequency) nor the use of antithetical/reverse‐worded items on OCB scales. The meta‐analysis of correlations showed that self‐ and other‐ratings are moderately correlated but that self–other convergence is higher when antithetical items are not used and when agreement response scales are used. In addition, self‐ratings and supervisor‐ratings showed significantly more convergence than self‐ratings and coworker‐ratings. Finally, an evaluation of self‐rated and other‐rated OCB nomological networks showed that although self‐rated and other‐rated OCBs have similar patterns of relationships with common correlates, other‐rated OCB generally contributed negligible incremental variance to correlates and only contributed appreciable incremental variance to other‐rated behavioral variables (e.g., task performance and counterproductive work behavior). Implications and future research directions are discussed, particularly regarding the need to establish a nomological network for other‐rated OCB. Copyright © 2013 John Wiley & Sons, Ltd.     

It takes more than a village: the challenges of co-management in Uganda's fishery and forestry sectors

Decentralisation policies in least developed countries have emerged in response to failed centralised natural resource governance programmes because high-value natural resources are distributed unequally, with central governments often reaping more than local-level users. Current natural resource governance institutions have been created to remedy the problems that central governments formerly posed. Here, we argue that Uganda's forestry and fishery resources are biologically diverse and thus amenable to current decentralised management programmes, provided that there is compromise between market values and local cultural and subsistence values and uses. We observe, however, Uganda's current institutional arrangement favours the former over the latter and determine that successful natural resource decentralisation requires strengthening local-level natural resource institutions with increased fiscal flow, enforcement, monitoring and judicial powers. A strong and reliable partnership between local-level resource users and the central government is necessary for this to occur.     

Growth and damping of interfacial waves on a diffuse interface

The resonant interaction of surface and internal waves produces a nonlinear mechanism for energy transfer among wave components in oceans, lakes, and estuaries. In many field situations, the stratification may be well approximated by a two-layer fluid with a diffuse interface. The growth and damping rates of sub-harmonic interfacial waves generated by a surface wave through a three-wave resonant interaction are measured in the laboratory. These measurements are compared with theoretical predictions. A diffuse interface reduces the damping rate and increases the growth rate. The predicted growth rate provides excellent comparison with the laboratory measurements. The inclusion of the effects of a diffuse interface significantly improve the comparison.     

Increased primary production shifts the structure and composition of a terrestrial arthropod community

Numerous studies have examined relationships between primary production and biodiversity at higher trophic levels. However, altered production in plant communities is often tightly linked with concomitant shifts in diversity and composition, and most studies have not disentangled the direct effects of production on consumers. Furthermore, when studies do examine the effects of plant production on animals in terrestrial systems, they are primarily confined to a subset of taxonomic or functional groups instead of investigating the responses of the entire community. Using natural monocultures of the salt marsh cordgrass Spartina alterniflora, we were able to examine the impacts of increased plant production, independent of changes in plant composition and/or diversity, on the trophic structure, composition, and diversity of the entire arthropod community. If arthropod species richness increased with greater plant production, we predicted that it would be driven by: (1) an increase in the number of rare species, and/or (2) an increase in arthropod abundance. Our results largely supported our predictions: species richness of herbivores, detritivores, predators, and parasitoids increased monotonically with increasing levels of plant production, and the diversity of rare species also increased with plant production. However, rare species that accounted for this difference were predators, parasitoids, and detritivores, not herbivores. Herbivore species richness could be simply explained by the relationship between abundance and diversity. Using nonmetric multidimensional scaling (NMDS) and analysis of similarity (ANOSIM), we also found significant changes in arthropod species composition with increasing levels of production. Our findings have important implications in the intertidal salt marsh, where human activities have increased nitrogen runoff into the marsh, and demonstrate that such nitrogen inputs cascade to affect community structure, diversity, and abundance in higher trophic levels.     

Multifoci effects of injustice on counterproductive work behaviors and the moderating roles of symbolization and victim sensitivity

Past research suggests that employees, in response to workplace experiences, selectively engage in targeted counterproductive work behaviors (CWBs). Taking a retributive justice and target similarity perspective, we predict that employee perceptions of unfairness from the organization uniquely predict CWB specifically targeted at the organization whereas employee perceptions of supervisory unfairness uniquely predict CWB specifically targeted at the supervisor. We further hypothesized that moral identity‐symbolization would strengthen these target‐similar relationships. Finally, drawing from the sensitivity to mean intentions model, we hypothesized that victim sensitivity would not only strengthen these target‐similar relationships but also lead to cross‐foci effects of multifoci fairness perceptions on targets of CWB. Results from 3 field studies of full‐time employees provided support for most of our hypothesized relationships.     

Trophic dynamics of U, Ni, Hg and other contaminants of potential concern on the Department of Energy’s Savannah River Site

The Department of Energy’s Savannah River Site is a former nuclear weapon material production and current research facility located in South Carolina, USA. Wastewater discharges from a fuel and nuclear reactor target manufacturing facility released depleted and natural U, as well as other metals into the Tims Branch-Steed Pond water system. We investigated the current dynamics of this system for the purposes of environmental monitoring and assessment by examining metal concentrations, bioavailability, and trophic transfer of contaminants in seven ponds. Biofilm, detritus, and Anuran and Anisopteran larvae were collected and analyzed for stable isotopes (δ ¹⁵N, δ ¹³C) and contaminants of potential concern (COPC) with a focus on Ni, U, and Hg, to examine metal mobility. Highest levels of Ni and U were found in biofilms U (147 and 332 mg kg^?1 DW, respectively), while highest Hg levels were found in tadpoles (1.1 mg kg^?1 DW). We found intraspecific biomagnification of COPCs as expressed through stable isotope analysis. Biofilms were the best indicators for contamination and Anuran larvae with the digestive tract removed were the best indicators of the specific bioavailability of the focal metals. Monitoring data showed that baseline δ ¹⁵N values differed between ponds, but within a pond, values were stable throughout tadpole Gosner stage, strengthening the case to use this species for monitoring purposes. It is likely that there still is risk to ecosystem integrity as COPC metals are being assimilated into lower trophic organisms and even low levels of this mixture has shown to produce deleterious effects to some wildlife species.