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David Alexander JC Gaillard Ilan Kelman Fausto Marincioni Edmund Penning‐Rowsell Dewald van Niekerk Lauren J. Vinnell 《Disasters》2021,45(1):5-18
Nowadays there are approximately 80 Anglophone journals that deal primarily with disaster risk reduction (DRR) and allied fields. This large array signals a sustained, if uneven, growth in DRR scholarship but also competition between the offerings of different publishers and institutions. The purpose of this article is first to summarise the development of academic publishing on DRR from its early beginnings to the present day. The paper then evaluates the current state of publishing in this field and discusses possible future trends. Next, it identifies some possible opportunities, challenges, expectations, and commitments for journal editors both within DRR and academia more broadly, including those that refer to changes in the use of terminology, the relentless increase in the number of papers submitted, the expansion and dangers of predatory journals, different peer review models, open access versus paywalls, citations and bibliography metrics, academic social networks, and copyright and distribution issues. 相似文献
74.
The evolution of empty nuptial gifts in a dance fly, Empis snoddyi (Diptera: Empididae): bigger isn't always better 总被引:2,自引:0,他引:2
Jennifer A. Sadowski Allen J. Moore Edmund D. Brodie III 《Behavioral ecology and sociobiology》1999,45(3-4):161-166
Adaptive female choice is thought to have led to the evolution of nutritionally valuable nuptial gifts in many insect species.
However, in several dance fly species, males offer and females accept “empty gifts” with no nutritional value. In the species
studied here, Empis snoddyi Steyskal, males produce empty balloons comprised of hundreds of silk bubbles and form mating swarms that females approach
to investigate males. Males within the swarm engage in agonistic interactions. The empty balloon has been hypothesized to
be an indicator of male condition such that males with larger balloons are predicted to have higher mating success and be
more successful in male-male interactions than males with smaller balloons. We examined the role of male body size and balloon
size in the context of intersexual and intrasexual selection. We found that neither male body size nor balloon size affected
the outcome of pairwise male-male interactions. Using multiple-regression techniques, we found significant linear selection
for increasing male body size and decreasing balloon size associated with mating success, a surprising result given a positive
relationship between male body size and balloon size. A visualization of selection showed the highest peak of male mating
success for larger males with intermediate-size balloons. These results can be explained by a trade-off between long-range
attraction of females using large balloons and close-range attraction of females via improved flying efficiency associated
with smaller balloons. Both male body size and balloon size are important components in determining male mating success; however,
the empty balloon does not appear to play a typical role as a sexually selected ornament.
Received: 29 December 1997 / Accepted after revision: 7 October 1998 相似文献
75.
Tidal streams are ecologically important components of lotic network, and we identify dissolved oxygen (DO) depletion as a potentially important stressor in freshwater tidal streams of northern New Zealand. Other studies have examined temporal DO variability within rivers and we build on this by examining variability between streams as a basis for regional-scale predictors of risk for DO stress. Diel DO variability in these streams was driven by: (1) photosynthesis by aquatic plants and community respiration which produced DO maxima in the afternoon and minima early morning (range, 0.6-4.7 g/m(3)) as a product of the solar cycle and (2) tidal variability as a product of the lunar cycle, including saline intrusions with variable DO concentrations plus a small residual effect on freshwater DO for low-velocity streams. The lowest DO concentrations were observed during March (early autumn) when water temperatures and macrophyte biomass were high. Spatial comparisons indicated that low-gradient tidal streams were at greater risk of DO depletions harmful to aquatic life. Tidal influence was stronger in low-gradient streams, which typically drain more developed catchments, have lower reaeration potential and offer conditions more suitable for aquatic plant proliferation. Combined, these characteristics supported a simple method based on the extent of low-gradient channel for identifying coastal streams at risk of DO depletion. High-risk streams can then be targeted for riparian planting, nutrient limits and water allocation controls to reduce potential ecological stress. 相似文献
76.
Qing Huang Shuiyuan Cheng Rhoda E. Perozzi Edmund F. Perozzi 《Environmental Modeling and Assessment》2012,17(5):527-538
A coupled MM5–CAMx air quality modeling system was used to simulate SO2 concentrations in Beijing, China during the heating season. Particulate matter source apportionment technology was employed to investigate the apportionment of SO2 sources in the study area. Comprehensive analysis of the industry and region revealed that the most important SO2 contributors were publicly and privately supplied heating emission sources and other industry emission sources from the urban areas of Beijing, with 66.1?% of the emission source contribution ratio. Four SO2 emission reduction scenarios based on our SO2 source apportionment research were established to assess the potential for improving the SO2 air quality in Beijing during the heating season. By weighing the desired SO2 improvement, the availability of technology, and economic considerations, a suitable SO2 reduction plan was able to be recommended for Beijing city. 相似文献
77.
Devolution of responsibilities is transforming how flood risk is managed in many countries. Research assessing the emergence and role of a new element in the governance of flood risk management in England explored the numerous ‘flood action groups’ that have developed over the last decade. We identified two broad categories of relationship between the public and authorities. The first displays ‘contractual’ characteristics: a level of protection provided by the authority in exchange for taxes or similar support. The second embodies a ‘collaborative’ relationship: public knowledge, social and financial resources are equal and complementary to those of authority, and seeking ‘collective security’. In general, the former were more successful than the latter, but common lessons were that success in FRM should not be defined purely as the ability to prevent flooding, but as the ability to access a variety of resources across different levels of society at different stages of flood risk management. 相似文献
78.
79.
Samuel S. Butcher Edmund M. Sorenson 《Journal of the Air & Waste Management Association (1995)》2013,63(7):724-728
Particulate emission factors for two wood stove models have been determined for two types of fuel and a range of operating conditions. The emission factors range from 1 g/kg (fuel) to 24 g/kg. A model is presented which represents the emission factor as a simple function of the ratio of fuel load to combustion rate, or the length of time between refueling. This model is felt to be appropriate for evaluating the impact of wood-based residential space heating on ambient air concentrations of particulate matter If certain assumptions can be made about stove operating conditions. An application of the emission factor model to a typical community suggests that the contribution of wood stoves to ambient particulate levels might reach 100 μg/m3 if the entire heating load were carried by wood. Preliminary analyses of the particulate matter Indicate that benzene extractables range from 42% of the total particulate mass at short refuel times to 67% at longer refuel times. About 45% of the mass of benzene extractables appeared in the neutral fraction of acid base extractions. Polycyclic aromatic hydrocarbons are expected to be included in this neutral fraction. 相似文献
80.
A comparison of mussels (Perna viridis) and semi-permeable membrane devices (SPMDs) was carried out at five sites, representing a gradient of contaminant concentrations, in Hong Kong coastal waters. Mussels, originally collected from a “clean” location, were deployed along with SPMDs at each site for 30 days. Analyses for chlorinated pesticides and polychlorinated biphenyls (PCBs) indicated that SPMDs have potential as monitoring tools, and to some extent can overcome the problems associated with mussels, such as natural variability, differing age, sex, and physical condition. However, in most cases, SPMDs failed to rank the sites in the same order as mussels in terms of contaminant concentrations. Nonetheless, in localities where mussels cannot survive – as shown at Kwun Tong in the present experiment – SPMDs may be valuable in providing an indication of potentially bio-available lipophilic pollutants. 相似文献