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121.
Carabeo-Pérez Annerys Odales-Bernal Leyanet López-Dávila Edelbis Jiménez Janet 《Journal of Material Cycles and Waste Management》2021,23(4):1404-1411
Journal of Material Cycles and Waste Management - Anaerobic digestion technology is a feasible alternative for wastes environmental treatment, nutrients recovery (as biofertilizer) and biomethane... 相似文献
122.
Fraser McLeod Gunes Erdogan Tom Cherrett Tolga Bektas Nigel Davies Duncan Shingleton Chris Speed Janet Dickinson Sarah Norgate 《Waste management (New York, N.Y.)》2014,34(2):273-280
Collection costs associated with servicing a major UK charity’s donation banks and collecting unsold goods from their retail shops can account for up to 20% of the overall income gained. Bank and shop collections are commingled and are typically made on fixed days of the week irrespective of the amounts of materials waiting to be collected. Using collection records from a major UK charity, this paper considers what vehicle routing and scheduling benefits could accrue if bank and shop servicing requirements were monitored, the former using remote sensing technology to allow more proactive collection scheduling. A vehicle routing and scheduling algorithm employing tabu search methods was developed, and suggested time and distance savings of up to 30% over the current fixed schedules when a minimum bank and shop fill level of between 50% and 60% was used as a collection trigger. For the case study investigated, this led to a potential revenue gain of 5% for the charity and estimated CO2 savings of around 0.5 tonnes per week across the fleet of six heterogeneous vehicles. 相似文献
123.
124.
R. Terry Bowyer Janet L. Rachlow Kelley M. Stewart Victor Van Ballenberghe 《Behavioral ecology and sociobiology》2011,65(12):2251-2260
Evidence of female fomentation of male–male aggression as a mechanism of mate choice is rare, especially in mammals. Female
choice of mates in polygynous species may be masked by intense male competition or by males attempting to restrict female
choice. We studied protest moans of female Alaskan moose Alces alces gigas in interior Alaska, USA, from 1987 to 1990, to determine if moans incited male–male aggression. Alaskan moose exhibit a mating
system in which one dominant male (the harem master) herds, defends, courts, and attempts to mate with females in his harem.
Protest moans were given by females only in response to courtship. We hypothesized that if protest moans were related to females
reducing harassment and exercising mate choice, females should give protest moans more frequently when courted by small males
and less often when courted by large males, and that rates of male–male aggression would be elevated following protest moans.
Harems were composed of one large male, with a mean of 4.4 females (median = 3 females); 10% of 132 harems included ≥10 females.
The temporal pattern of protest moans from late August through November was associated with, but tended to lag behind, mating
behavior. The rate of protest moans given by females decreased with increasing size of males courting them. Male–male aggression
was significantly less during periods without protest moans than during periods in which protest moans occurred. These results
indicate that female moose gave protest moans to reduce harassment by smaller males, and assure a mating opportunity with
the most dominant male. Such a subtle mechanism of indirect mate choice by females may occur in other vertebrates in which
choice is limited by a mating system in which male–male combat and male dominance over females reduces opportunities for female
choice. The importance of female choice may be undervalued in studies of sexual selection in mammals. 相似文献
125.
Studies of collaborative watershed groups show that effective leadership is an important factor for success. This research
uses data from in-depth interviews and meeting observation to qualitatively examine leadership in a Midwestern collaborative
watershed group operating with government funding. One major finding was a lack of role definition for volunteer steering-committee
members. Lack of role clarity and decision-making processes led to confusion regarding project management authority among
the group, paid project staff members, and agency personnel. Given the important role of government grants for funding projects
to protect water quality, this study offers insight into leadership issues that groups with Clean Water Act Section 319 (h)
funds may face and suggestions on how to resolve them. 相似文献
126.
127.
Janet M. Lapierre Daniel J. Mennill Elizabeth A. MacDougall-Shackleton 《Behavioral ecology and sociobiology》2011,65(11):2149-2160
In many songbirds, individuals have repertoires of multiple song types, some of which may be shared with others in the local
area. Hypotheses about the evolution of song repertoires differ as to whether selection acts primarily on repertoire size
itself or the ability to match songs of neighbours. We used a 16-channel acoustic location system to record neighbourhoods
of song sparrows (Melospiza melodia melodia) during the dawn chorus. We asked whether males sing all songs with similar frequency as predicted by the Repertoire Size Hypothesis, whether males preferentially sing highly shared songs as predicted by the General Sharing Hypothesis, or whether use of highly shared songs is associated with phenotype as predicted by the Conditional Sharing Hypothesis. Contrary to the Repertoire Size Hypothesis, most males did not sing all songs equally often. Contrary to the General Sharing
Hypothesis, we found no general tendency to overproduce highly shared songs. The degree to which males overproduced highly
shared songs was repeatable across days, indicating consistent individual differences, and varied across neighbourhoods. Moreover,
and consistent with the Conditional Sharing Hypothesis, older males were more likely to overproduce highly shared songs. If
highly shared song is a conventional signal of aggression, with the threat of receiver retaliation maintaining honesty, older
males may be more willing or able to risk conflict. Alternatively, males may learn which songs are effective signals for an
area. Finally, age-related variation in vocal performance may shape the adaptive value of highly shared song. 相似文献
128.
Sara M. Aschmann Janet Arey Roger Atkinson 《Atmospheric environment (Oxford, England : 1994)》2010,44(32):3970-3975
Aromatic hydrocarbons are important constituents of vehicle exhaust and of non-methane volatile organic compounds in ambient air in urban areas. It has recently been proposed that dealkylation is a significant pathway for the OH radical-initiated reactions, leading to the formation of phenolic compounds and/or oxepins (Noda, J., Volkamer, R., Molina, M.J., 2009. Dealkylation of alkylbenzenes: a significant pathway in the toluene, o-, m-, and p-xylene + OH reaction. Journal of Physical Chemistry A 113, 9658–9666.). We have investigated the formation of cresols from the reactions of OH radicals with m-xylene and p-cymene, and obtain upper limits of <1% for formation of each cresol isomer from OH + m-xylene and <2% for formation of each cresol isomer from OH + p-cymene. In addition, we have measured the formation yield of 4-methylacetophenone (the major product formed subsequent to H-atom abstraction from the CH(CH3)2 group) in the OH + p-cymene reaction to be 14.8 ± 3.2%, and estimate that H-atom abstraction from the CH3 and CH(CH3)2 groups in p-cymene accounts for 20 ± 4% of the overall OH radical reaction. We also used a relative rate technique to measure the rate constant for the reaction of OH radicals with 4-methylacetophenone to be (4.50 ± 0.43) × 10?12 cm3 molecule?1 s?1 at 297 ± 2 K. 相似文献
129.
The chaotic physical and chemical environment at deep-sea hydrothermal vents has been associated with an ecosystem with few
predators, arguably allowing the habitat to provide refuge for vulnerable species. The dominance of endemic limpets with thin,
open-coiled shells at north Pacific vents may support this view. To test their vulnerability to predation, the incidence of
healed repair scars, which are argued to reflect non-lethal encounters with predators, were examined on the shells of over
5,800 vent limpets of Lepetodrilus fucensis McLean (1988) that were collected from 13 to 18 August 1996. Three vent fields on the Juan de Fuca Ridge at ca. 2,200 m depth were sampled,
two within 70 m of 47°56.87′N 129°05.91′W, and one at 47°57.85′N 129°05.15′W with the conspicuous potential limpet predators,
the zoarcid fish Pachycara gymninium Anderson and Peden (1988), the galatheid crab Munidopsis alvisca Williams (1988), and the buccinid snail Buccinum thermophilum Harasewych and Kantor (2002). Limpets from the predator-rich vent were most often scarred, a significant difference created by the high incidence of
scars on small (<4 mm long) limpets in this sample. Collected with the limpets were small (median shell diameter 4.4 mm) buccinids.
They, rather than the larger, more conspicuous mobile fishes and crabs are argued to be the shell-damaging predator.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
130.
Groundwater management by watershed agencies: an evaluation of the capacity of Ontario's conservation authorities 总被引:4,自引:0,他引:4
Watershed-based resource management organizations around the world are becoming more involved in groundwater management. This reflects, among other considerations, growing awareness of the critical role that these local agencies can and should play in the management of groundwater resources. Ontario's conservation authorities (CAs) are an important example. CAs are taking on new responsibilities for groundwater data collection, monitoring and planning. Unfortunately, not all local organizations are equally capable of participating effectively in groundwater management. This certainly is the case among Ontario's 38 CAs, which have highly variable levels of financial and staff resources. Local capacity for water management can be explored from the perspective of the institutional environment, the watershed community, and the financial, technical and staff resources of the organizations. This paper presents an evaluation of the groundwater management capacity of Ontario's conservation authorities, drawing on two detailed case studies (the Upper Thames River CA and the Ganaraska Region CA), and additional data gathered from all 38 CAs. Institutional issues, such as the clarity of management roles and senior government commitment to local management, as well as resourcing concerns, local working relationships, and public support, largely determine the capacity of CAs to expand their involvement in groundwater management. Strengthening the capacity of watershed-based agencies to participate in groundwater management is an important challenge in all jurisdictions, as these agencies are well placed to reinforce municipal groundwater management by identifying local needs and trends, facilitating communication and cooperation, and promoting best management practices. 相似文献