Spatial and temporal dynamics at manakin leks: reconciling lek traditionality with male turnover

Leks, display grounds where males congregate and females visit to copulate, are typically traditional in location, despite often high turnover of individual males. How leks can persist in face of male turnover is not well understood, in part due to a lack of detailed field data allowing for a clear understanding of lek dynamics. We followed the fate of individual males at 11 to 15 leks of the blue-crowned manakin Lepidothrix coronata across four breeding seasons to gain insights on how leks are formed and changed in space and time. Between years, leks were traditional in location despite changes in territory ownership due to male disappearance and recruitment. New males were equally likely to recruit by taking over existing territories or by establishing new territories. Recruitment was influenced by age, as recruits were more likely to be adults than subadults. Lek size did not affect the probabilities of a male recruiting or persisting at a territory, and vocalization rate, a correlate of mating success in this population, did not affect male persistence. We used our field data to model changes in lek size and composition over longer periods of time (100 years) to understand how lek traditionality can be reconciled with high male turnover. Our simulations showed that leks in our population rapidly stabilize in size despite changes in territory ownership and that rates of male recruitment and disappearance compensate each other, such that leks have the potential to persist for several decades after the original males have disappeared from them.     

Mediated Modeling in Water Resource Dialogues Connecting Multiple Scales

We observe a paradigm shift toward collaborative, multi‐level (from local to global) water management and suggestions for scale‐related design principles in the literature. Decision‐support tools are needed that can help achieve scale design principles. Mediated modeling (MM) refers to model building with people, rather than for people. This tool belongs to a family of participatory, systems oriented tools. This article explores their suitability for addressing challenges and principles that arise at multiple‐scales. MM can promote the understanding of cross‐level and cross‐scale links, creating salient, credible, and legitimate knowledge and encouraging boundary functions. Prerequisites for successful MM processes include an openness and willingness to collaborative learning. As new “meso‐level” institutions emerge to address complex challenges in water management collaboratively, tools like MM may play an important role in structuring dialogues, developing adaptive management capacity and advance an ecosystem services approach.     

Changes in Sediment Sources following Wildfire in Mountainous Terrain: A Paired–Catchment Approach,British Columbia,Canada

This paper describes a study examining the potential of mineral magnetic, geochemical and organic properties to determine if a 2003 wildfire in a catchment in British Columbia, Canada, caused a change in the sources of the suspended sediment transported in the channel relative to a nearby unburnt (reference) catchment. The results show that some of the properties offer the potential to determine sediment sources in the unburnt catchment. However, the 2003 wildfire modified the concentrations of some properties and this can either compromise or enhance their ability as tracers in the burnt catchment. At present, the source tracing results are inconclusive. This has implications for the use of certain properties as fingerprints and raises important issues about approaches to sediment source identification.     

Alumni and their alma mater: A partial test of the reformulated model of organizational identification

Organizational identification is defined as a perceived oneness with an organization and the experience of the organization's successes and failures as one's own. While identification is considered important to the organization, it has not been clearly operationalized. The current study tests a proposed model of organizational identification. Self-report data from 297 alumni of an all-male religious college indicate that identification with the alma mater was associated with: (1) the hypothesized organizational antecedents of organizational distinctiveness, organizational prestige, and (absence of) intraorganizational competition, but not with interorganizational competition, (2) the hypothesized individual antecedents of satisfaction with the organization, tenure as students, and sentimentality, but not with recency of attendance, number of schools attended, or the existence of a mentor, and (3) the hypothesized outcomes of making financial contributions, willingness to advise one's offspring and others to attend the college, and participating in various school functions. The findings provide direction for academic administrators seeking to increase alumni support, as well as for corporate managers concerned about the loyalty of workers in an era of mergers and takeovers.     

Book reviews

Ecological Politics in an Age of Risk. Ulrich Beck, translated by Amos Weisz, 1995 Cambridge, Polity Press, first published Germany 1988. ISBN 0 7456 077632, hb £39.50; ISBN 0 7456 13772, pk £12.95

Environmentally Sustainable Business: a local and regional perspective. Peter Roberts, 1995, London, Paul Chapman. ISBN 1 85396 240 6, price not given

Methods of Environmental Impact Assessment. Peter Morris & Riki Therivel (Eds) 1995, London, UCL Press, 378 pp. ISBN 1 85728 117 9, hb £45.00; 1 85728 118 7, pb £14.95

A Guide to Local Environmental Auditing. Hugh Barton & Noel Bruder, 1995, London, Earthscan, 370 pp. ISBN 1 85 383 2340, pb £18.95

Household Waste Recycling. Richard Waite, 1995, London, Earthscan, ISBN 1 8538 3 2421, hb £29.95

A Seed in Time: Proceedings of the 3rd International Conference on Urban and Community Forestry. Forestry Commission, 1994. ISBN 0 885 38 328 3, £9.50 inc p&p (Copies available from: Marcus Sangster, Forestry Commission, 231 Corstorphine Road, Edinburgh EH12 7AT)

Environmental Policy in New Zealand: the politics of clean and green? Tom Buhrs & Robert Bartlett, 1993, Auckland, Oxford University Press viii + 192 pp.

Green Politics. Stephen Rainbow, 1993, Auckland, Oxford University Press xv + 106 pp.

The Future of Community Lands: human resources. E. Ndione, P. DeLeener, M. Ndiaye, P. Jacolin & J.-P. Perier, 1995, London, Intermediate Technology, 236 pp. ISBN 1 339 2480, £14.95     

Social learning and sustainable communities: An interim assessment of research into sustainable communities projects in the UK

The delivery of many of the most pressing environmental issues will rely on changes in environmental attitudes and behaviour at community level. At a UN Special Session in 1997, the British Government highlighted its initiatives on Local Agenda 21 (LA21) and Going for Green (GFG) as significant advances. This paper adds a new perspective, drawing on the range of experiences of some of the research teams that have been working with local authorities on pilot Sustainable Community Projects (SCPs) in England and Scotland. It sheds light on three substantive themes: the tensions inherent in the implementation of internationally and nationally agreed goals through local action; the ambiguity of local agencies acting as facilitators of community ownership of processes, and the requirements for successful partnership between local authorities and higher education.     

Effects of petroleum contamination on soil microbial numbers, metabolic activity and urease activity

The influence of petroleum contamination on soil microbial activities was investigated in 13 soil samples from sites around an injection water well (Iw-1, 2, 3, 4) (total petroleum hydrocarbons (TPH): 7.5-78 mg kg⁻¹), an oil production well (Op-1, 2, 3, 4, 5) (TPH: 149-1110 mg kg⁻¹), and an oil spill accident well (Os-1, 2, 3, 4) (TPH: 4500-34 600 mg kg⁻¹). The growth rate constant (μ) of glucose stimulated organisms, determined by microcalorimetry, was higher in Iw soil samples than in Op and Os samples. Total cultivable bacteria and fungi and urease activity also decreased with increasing concentration of TPH. Total heat produced demonstrated that TPH at concentrations less than about 1 g kg⁻¹ soil stimulated anaerobic respiration. A positive correlation between TPH and soil organic matter (OM) and stimulation of fungi-bacteria-urease at low TPH doses suggested that TPH is bound to soil OM and slowly metabolized in Iw soils during OM consumption. These methods can be used to evaluate the potential of polluted soils to carry out self-bioremediation by metabolizing TPH.     

A New Method for the Rapid Determination of Volatile Organic Compound Breakthrough Times for a Sorbent at Concentrations Relevant to Indoor Air Quality

Abstract

The use of sorbents has been proposed to remove volatile organic compounds (VOCs) present in ambient air at concentrations in the parts-per-billion (ppb) range, which is typical of indoor air quality applications. Sorbent materials, such as granular activated carbon and molecular sieves, are used to remove VOCs from gas streams in industrial applications, where VOC concentrations are typically in the parts-per-million range. A method for evaluating the VOC removal performance of sorbent materials using toluene concentrations in the ppb range is described. Breakthrough times for toluene at concentrations from 2 to 7500 ppb are presented for a hydrophobic molecular sieve at 25% relative humidity. By increasing the ratio of challenge gas flow rate to the mass of the sorbent bed and decreasing both the mass of sorbent in the bed and the sorbent particle size, this method reduces the required experimental times by a factor of up to several hundred compared with the proposed American Society of Heating, Refrigerating, and Air-Conditioning Engineers method, ASHRAE 145P, making sorbent performance evaluation for ppb-range VOC removal more convenient. The method can be applied to screen sorbent materials for application in the removal of VOCs from indoor air.     

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.