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461.
462.
Public Participation Mechanisms in Environmental Disasters 总被引:1,自引:0,他引:1
This paper examines the role of public participation mechanisms in certain major environmental disasters. It examines situations in which people’s lifestyles or their lives have been directly threatened, and thus elicited citizen participation. Threatening issues often seem morally, physically, socially, economically, religiously, and otherwise unacceptable to a group. As will be presented in this paper, citizens voluntarily participate in a community activity when they see that their way of life has been threatened. An introductory historical perspective, the legal framework upon which it is based, and background information on the participatory mechanisms, all emphasizing the importance and need for empowering citizens with participatory skills so as to bring changes in the existing educational, legal, and social systems are presented. The major environmental accidents/disasters of Minamata, Japan; Bhopal, India; Seveso, Italy; Chernobyl, Ukraine; and Exxon-Valdez, Alaska are discussed, mainly to indicate the reaction, and the participatory mechanisms used by the affected communities in each of the sudden disasters that occurred. If citizens worldwide had been active participants in the environmental issues, it is quite possible that we would have experienced fewer environmental accidents. 相似文献
463.
(Crustacea:Hippidae) from three southern California (U.S.A.) beaches contained 0.9 to 24.1 μg/g dry wt saturated hydrocarbons, and 3.6 to 21.4 μg/g dry wt unsaturated hydrocarbons. Major constituents were (in wt. % total): n-alkanes (13.1%), heneicosapentaene plus heneicosahexaene (1.0%), squalene (5.1%), and unidentified polyenes (7.8%). Crabs from beaches exposed to small boat traffic and natural oil seepage were slightly and severely tainted, respectively, with petroleum hydrocarbons. Animals from San Nicolas Island (85 km offshore) contained only biogenic compounds. 相似文献
464.
Population dynamics and maturity parameters were analysed for seasonal samples of the oceanic ommastrephid squid Todarodes filippovae from off the coast of Tasmania Australia from 2002 to 2004. Based on assumed daily periodicity in statolith increments, T. filippovae had a life cycle of about a year with the sexually dimorphic females reaching their larger size by predominantly growing faster than males. Due to the small sample size of males, analysis was undertaken on female individuals only. Growth in all samples was best described by a power curve and varied annually, with significantly faster growth in 2001 compared to the subsequent 2 years. Seasonal growth rates also varied with autumn- and winter-hatched squid significantly faster than summer-hatched squid. Spring growth rates were intermediate but not significantly different to the other three seasons. Peak hatching periods occurred in late autumn and early winter. ANOVA revealed a season × year interaction for mantle length and total body weight. Pairwise comparisons showed that the annual differences were likely driven by smaller squid in autumn 2002 compared to autumn samples in the other 2 years. Pairwise comparisons also revealed seasonal differences with winter-caught squid smaller than those from the majority of other samples. There were no seasonal effects on mature female gonad weights but females caught in 2002 had significantly lighter gonad weights than females from the following 2 years. There were no consistent trends among seasons or years in the age structure of mature females. This study revealed the plasticity and flexibility in growth and maturity parameters in this species, with a preference for faster growth during cooler periods. 相似文献
465.
Ronald L. Rutowski George W. Gilchrist Barbara Terkanian 《Behavioral ecology and sociobiology》1987,20(5):319-322
Summary During copulation, males of the alfalfa butterfly, Colias eurytheme, transfer nutrients and sperm to the female. Recently mated males produce only about 40% of the quantity of material produced by males that have not recently mated (Rutowski and Gilchrist 1986). In this study, females that mated with recently mated males died sooner, had a lower lifetime egg output, and laid fewer eggs per day overall, but especially during the first 2 days after mating. We conclude that the effect of the materials (nutrients and sperm) passed by males at copulation on female oviposition and receptivity is such that the male's genetic return from nutrients passed is maximized. 相似文献
466.
Javier Tomás Audrey J. Geffen Richard S. Millner Carmen G. Piñeiro George Tserpes 《Marine Biology》2006,148(6):1399-1413
The composition of the opaque and translucent bands in the otoliths of European hake (Merluccius merluccius) from three different populations (Celtic Sea, Galicia shelf and Cretan Sea) was analysed with wavelength dispersive spectrometry
(WDS) and differences in Ca, Sr and Na were compared. The translucent bands (annual marks and checks altogether) were significantly
richer in Sr and Ca and significantly poorer in Na than opaque bands. Results support the idea of a more compact arrangement
of crystals in translucent bands compared to opaque. Analyses did not help to discriminate between putative annual marks and
checks. Clear differences in the range of Sr/Ca variation across the otolith as well as in the composition of the otolith
core were observed among the three populations. As a result it was possible to discriminate the natal origin of each fish
using the composition of the otolith core in Ca, Sr and Na. Nevertheless, the overall pattern across the otolith was similar
among the three populations suggesting the existence of ontogenetic trends. Variation of Na/Ca ratios was largely uninformative.
Based on these results, a conceptual model for hake is proposed which integrates the different sources of otolith Sr/Ca variation:
ambient Sr/Ca, endogenous cues (ontogeny) and exogenous cues (environment). 相似文献
467.
George Y. Jumper Edmund A. Murphy Frank H. Ruggiero John R. Roadcap Anthony J. Ratkowski Jean Vernin Hervé Trinquet 《Environmental Fluid Mechanics》2007,7(5):351-370
In July 2002, a multi-sensor campaign was conducted in southern France to investigate the hypothesized connection between
gravity waves and optical turbulence. A generalized scidar (GS) was mounted on the 1.93 m diameter telescope at l’Observatoire
de Haute-Provence (OHP). The GS provides continuous profiles of optical turbulence with 300 m vertical resolution from telescope
altitude up to 25 km. Thermosondes, which provide in situ measurement of optical turbulence by measuring temperature variance,
were launched at the OHP site and at a site approximately 20 km west-northwest of OHP. Gravity wave activity was deduced from
temperature and wind velocity measured by radiosondes, which are part of the thermosonde system. In this paper, gravity waves
were analyzed using techniques for simple two-dimensional mountain waves, with only fair results. Mesoscale models were run
at moderately high resolution for the period. The forecasts were analyzed for wave activity, and a post processor model was
used to diagnose the optical turbulence. Mountain waves were evident in the forecast, but quantitative comparison showed the
forecast to be inadequate in predicting wave strength. The forecast optical turbulence was in fair agreement with measurements
with notable exceptions.
This paper is declared a work of the U.S. Government and is not subject to copyright protection in the United States. The
U.S. Government’s right to retain a non-exclusive, royalty-free license in and to any copyright is acknowledged.
Presented at the Turbulence and Waves in Stably Stratified Atmospheric Shear Flows: Measurements, High Resolution Simulations
and Numerical Prediction Challenges Conference, 13–15 September 2004, Lighthill Institute of Mathematical Sciences, University
College London, London, UK. 相似文献
468.
J. Alan Pounds Michael P. L. Fogden Jay M. Savage & George C. Gorman 《Conservation biology》1997,11(6):1307-1322
469.
Summary Gregarious nymphs of the desert locust,Schistocerca gregaria (Forsk.) (Orthoptera: Acrididae) were more attracted to volatiles from mechanically damaged food plants used for rearing than to either the undamaged or damaged food plants not used as diet in Y-tube olfactometer assays. Comparative analysis of the volatile emissions from plants used for rearing and food plants not used for rearing,e.g. Sorghum bicolor, Pennisetum clandestinum, Schouwia thebaica, wheat (Triticum sp., var. Nyangumi),Zygophyllum simplex, Heliotropium undulatum andTribulus terrestris was carried out by GC, GC-EAD and GC-MS. Significant quantitative and qualitative differences were found in the volatile emissions and olfactory responses of nymphs in GC-EAD assays. Up to 33 compounds were identified in volatiles of the plants of which 9 evoked EAGs. EAG-active components included common green leaf compounds (E)-2-pentenal, (E)-2-hexenal, 4-methyl-3-pentenal, (E)-3-hexenyl acetate, (Z)-3-hexenyl acetate, (Z)-2-hexenyl acetate, (Z)-3-hexen-1-ol and (Z)-2-hexen-1-ol. (Z)-3-Hexenyl butyrate and (Z)-3-hexenyl isovalerate were detected in stimulatory amounts only in the volatiles ofS. thebaica. (E, Z)-2,6-Nonadienal was detected as a component in the volatiles ofT. terrestris and was highly stimulatory. In EAG assays with seven common green leaf volatiles, (Z)-3-hexenyl acetate was most stimulatory while hexanal was the least. No significant differences were recorded between antennal responses of males and females to the tested compounds. These results are discussed with regard to current hypotheses on host plant recognition through detection of their airborne volatiles and the learning behaviour by nymphs ofS. gregaria. 相似文献
470.
George A. Meindl Nicholas Schleissmann Brianna Sander Michael Lam Wyatt Parker Courtney Fitzgerald 《Chemistry and Ecology》2020,36(3):194-204
ABSTRACTHuman activity has led to widespread chemical alteration of natural environments. Aquatic ecosystems are especially susceptible to chemical changes, including those caused by runoff and invasive species. Here, we examined the effects of water chemistry, specifically sodium chloride as well as three metals (Ca, K, and Mn) known to differ between native and invasive wetland plant species’ leaf tissues, on the development of two model amphibians: the native Northern leopard frog, Lithobates pipiens, and the non-native African clawed frog, Xenopus laevis. We exposed frog eggs to metal treatment solutions and measured time to hatching (TTH), and following hatching, we exposed tadpoles to a lethal concentration of sodium chloride and recorded time to death (TTD). We found that increasing metal concentrations generally resulted in acceleration of TTH for Xenopus tadpoles, but had no effect on leopard frogs. However, increasing metal concentrations (Ca, Mn) increased leopard frog tadpole susceptibility to NaCl (decreased TTD), while increasing metal concentrations (Ca, K) generally resulted in decreased Xenopus tadpole susceptibility to NaCl. Overall, our data suggest that invasive amphibians may be more tolerant to chemical changes than native amphibians, including those driven by the introduction of invasive plant species. 相似文献