Contribution of Roads to Forest Fragmentation in the Rocky Mountains

The contribution of roads to forest fragmentation has not been adequately analyzed. We quantified fragmentation due to roads in a 30,213-ha section of the Medicine Bow-Routt National Forest in sout heastern Wyoming with several indices of landscape structure using a geographic information system. The number of patches, mean patch area, mean interior area, mean area of edge influence, mean patch perimeter, total perimeter, and mean patch shape identified patch- and edge-related landscape changes. Shannon-Wiener diversity, dominance, contagion, contrast, and angular second moment indicated effects on landscape diversity and texture. Roads added to forest fragmentation more than clearcuts by dissecting large patches into smaller pieces and by converting forest interior habitat into edge habitat. Edge habitat created by roads was 1.54–1.98 times the edge habitat created by clearcuts. The total landscape area affected by clearcuts and roads was 2.5–3.5 times the actual area occupied by these disturbances. Fragmentation due to roads could be minimized if road construction is minimized or rerouted so that its fragmentation effects are reduced. Geographic information system technology can be used to quantify the potential fragmentation effects of individual roads and the cumulative effects of a road network on landscape structure.     

Transport,deposition and biodegradation of particle bound polycyclic aromatic hydrocarbons in a tidal basin of an industrial watershed

Polycylic aromatic hydrocarbons (PAHs) are commoncontaminants in industrial watersheds. Their origin,transport and fate are important to scientists,environmental managers and citizens. The Philadelphia NavalReserve Basin (RB) is a small semi-enclosed embayment nearthe confluence of the Schuylkill and Delaware Rivers inPennsylvania (USA). We conducted a study at this site todetermine the tidal flux of particles and particle-boundcontaminants associated with the RB. Particle traps wereplaced at the mouth and inside the RB and in the Schuylkilland Delaware Rivers. There was net particle deposition intothe RB, which was determined for three seasons. Spring andfall depositions were highest (1740 and 1230 kg ofparticles, respectively) while winter deposition wasinsignificant. PAH concentrations on settling particlesindicated a net deposition of 12.7 g PAH in fall and 2.1 gPAH in spring over one tidal cycle. There was nosignificant PAH deposition in the winter. Biodegradationrates, calculated from ¹⁴C-labeled PAH substratemineralization, could attenuate only about 0.25% of the PAHdeposited during a tidal cycle in fall. However, in thespring, biodegradation could be responsible for degrading50% of the settling PAHs. The RB appears to be a sink forPAHs in this watershed.     

Information,beliefs, and motivation: The antecedents to human resource attributions

Despite significant interest in the attributions employees make about their organization's human resource (HR) practices, there is little understanding of the antecedents of HR attributions. Drawing on attribution theory, we suggest that HR attributions are influenced by information (perceptions of distributive and procedural fairness), beliefs (organizational cynicism), and motivation (perceived relevance). We test a model through a two‐wave survey of 347 academic faculty in the United Kingdom, examining their attributions of the purpose of their institution's workload management framework. After two preliminary studies (an interview study and a cross‐sectional survey) to establish contextually relevant attributions, we find that fairness and cynicism are important for the formation of internal attributions of commitment but less so for cost‐saving or exploitation attributions. Fairness and cynicism also interact such that distributive fairness buffers the negative attributional effect of cynicism, and individuals are more likely to attribute fair procedures to external forces if they are cynical about their organization. This study furthers the application of attribution theory to the organizational domain while making significant contributions to our understanding of the HR‐performance process.     

Estimating industrial solid waste and municipal solid waste data at high resolution using economic accounts: an input–output approach with Australian case study

In publicly available waste reports only the totals of waste produced for municipal, or industry waste typically feature. The types of waste generated and the generating industry sector are usually omitted. We propose the direct inputs waste estimation methodology to create a detailed estimate of municipal solid waste and industrial solid waste for an economy (including sectoral and waste type disaggregation) using a top-down estimation methodology that links the aforementioned limited publicly available waste data with an input–output table’s direct inputs (A) matrix. We then provide an application of the direct inputs waste estimation methodology upon the 2008 waste generation of Australia resulting in a 344 industry sector and 14 waste type data set. The resulting estimation gives unique insights into Australian waste generation; including the large C&I tonnages of waste estimated to be produced from the Service sectors such as the Education, Hospitality, and Health sectors as well as the large amount of food waste produced throughout the economy.     

Quantitative tools for implementing the new definition of significant portion of the range in the U.S. Endangered Species Act

In 2014, the Fish and Wildlife Service (FWS) and National Marine Fisheries Service announced a new policy interpretation for the U.S. Endangered Species Act (ESA). According to the act, a species must be listed as threatened or endangered if it is determined to be threatened or endangered in a significant portion of its range (SPR). The 2014 policy seeks to provide consistency by establishing that a portion of the range should be considered significant if the associated individuals’ “removal would cause the entire species to become endangered or threatened.” We reviewed 20 quantitative techniques used to assess whether a portion of a species’ range is significant according to the new guidance. Our assessments are based on the 3R criteria—redundancy (i.e., buffering from catastrophe), resiliency (i.e., ability to withstand stochasticity), and representation (i.e., ability to evolve)—that the FWS uses to determine if a species merits listing. We identified data needs for each quantitative technique and considered which methods could be implemented given the data limitations typical of rare species. We also identified proxies for the 3Rs that may be used with limited data. To assess potential data availability, we evaluated 7 example species by accessing data in their species status assessments, which document all the information used during a listing decision. In all species, an SPR could be evaluated with at least one metric for each of the 3Rs robustly or with substantial assumptions. Resiliency assessments appeared most constrained by limited data, and many species lacked information on connectivity between subpopulations, genetic variation, and spatial variability in vital rates. These data gaps will likely make SPR assessments for species with complex life histories or that cross national boundaries difficult. Although we reviewed techniques for the ESA, other countries require identification of significant areas and could benefit from this research.     

Health impact assessment of air pollutants during the COVID-19 pandemic in a Brazilian metropolis

Environmental Science and Pollution Research - Studies around the world have revealed reduced levels of atmospheric particulate matter in periods of greatest human mobility restriction to contain...     

Dynamic stoichiometric response to food quality fluctuations in the heterotrophic dinoflagellate Oxyrrhis marina

With respect to nutrients, plants are rather non-homoeostatic while most metazoans have much more confined ranges of nutrient ratios. It was recently highlighted that the homoeostatic ability of microzooplankters lies in between these two extremes. Nevertheless, we know very little on the dynamics of stoichiometric changes. Hence, we investigated how the stoichiometry of the heterotrophic dinoflagellate Oxyrrhis marina is affected (1) during a starvation period and (2) when fed nutrient deplete Rhodomonas salina after having been pre-conditioned on nutrient replete algae and vice versa. We observed that the dinoflagellate was able to maintain its N:P ratio constant over 78 h of starvation. We inferred that under starvation, nitrogen-limited O. marina mainly used fat as energy source while nitrogen-rich individuals also used proteins as fuel in cellular respiration. Further, we showed that O. marina presents resistance to nutrient limitation, with stronger regulation against P-limitation than against N-limitation. This resilience in microzooplankton stoichiometry following food quality stress would have great implications for both top-down (nutrient remineralisation) and bottom-up controls (quality as food).