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11.
The first part of this paper discusses the links between hazard, risk and vulnerability (HRV) analysis and the development of mitigative strategies. The second part discusses the need to include public participation when completing an HRV analysis. Two current HRV models are used to illustrate the general failure of HRV analysis to include public participation. The third part of this paper provides a brief overview of the Hazard, Impact, Risk and Vulnerability (HIRV) model and its use of public participation. The paper concludes by offering a synopsis of a case study in the town and regional area surrounding Barriere, British Columbia, Canada. This case study demonstrates a positive outcome when public participation is incorporated into an HIRV analysis.  相似文献   
12.
越南的养虾业正处在对生产体系的基础改造,使其转变成一个重要产业的过程中.该地区其他国家的经验,特别是高投入生产体系占主导地位的泰国的经验表明,现在正是通过干预使养虾业改道进入在生态、社会和经济上更可持续的道路.在泰国,实施强化的体系和复杂的产业组织的多年经验并没有获得可持续的解决办法.这里所面临的任务是使社会重新赢得控制并沿着更有效和良性发展的道路改变改革的发展方向.我们的分析结果表明,这两个国家的现行方法不可能使养虾业可持续的发展,需要对整个对虾的生产、喂养、加工、供销及管理的方式进行全面改革.  相似文献   
13.
The integrity of social insect colonies is maintained by members recognising and responding to the chemical cues present on the cuticle of any intruder. Nevertheless, myrmecophiles use chemical mimicry to gain access to these nests, and their mimetic signals may be acquired through biosynthesis or through contact with the hosts or their nest material. The cuticular hydrocarbon profile of the myrmecophilous salticid spider Cosmophasis bitaeniata closely resembles that of its host ant Oecophylla smaragdina. Here, we show that the chemical resemblance of the spider does not arise through physical contact with the adult ants, but instead the spider acquires the cuticular hydrocarbons by eating the ant larvae. More significantly, we show that the variation in the cuticular hydrocarbon profiles of the spider depends upon the colony of origin of the ant larvae prey, rather than the parentage of the spider.  相似文献   
14.
Foraging desert ants, Cataglyphis fortis, encounter different sequences of visual landmarks while navigating by path integration. This paper explores the question whether the storage of landmark information depends on the context in which the landmarks are learned during an ant's foraging journey. Two experimental set-ups were designed in which the ants experienced an artificial landmark panorama that was placed either around the nest entrance (nest marks) or along the vector route leading straight towards the feeder (route marks). The two training paradigms resulted in pronounced differences in the storage characteristics of the acquired landmark information: memory traces of nest marks were much more robust against extinction and/or suppression than those of route marks. In functional terms, this result is in accord with the observation that desert ants encounter new route marks during every foraging run but always pass the same landmarks when approaching the nest entrance.  相似文献   
15.
Population differences in anti-predator behaviour have been demonstrated in several species, although less is known about the genetic basis of these traits. To determine the extent of genetic differences in boldness (defined as exploration of a novel object) and shoaling within and between zebrafish (Danio rerio) populations, and to examine the genetic basis of shoaling behaviour in general, we carried out a study that involved laboratory-raised fish derived from four wild-caught populations. Controlling for differences in rearing environment, significant inter-population differences were found in boldness but not shoaling. A larger shoaling experiment was also performed using one of the populations as the basis of a North Carolina type II breeding design (174 fish in total) to estimate heritability of shoaling tendency. A narrow-sense heritability estimate of 0.40 was obtained, with no apparent dominance effects.  相似文献   
16.
17.
Community mitigation of hazard impact requires hazard knowledge and preparedness on the part of the members of diverse and complex communities. Longitudinal research in the tropical cyclone prone north of Australia has gathered extensive datasets on community awareness, preparedness and knowledge, in order to contribute to education campaigns and mitigation strategies. Data have been used to identify issues of vulnerability to cyclones and capacity to deal with the hazard. This has been developed as a community vulnerability and capacity model that may be applied to diverse communities in order to assess levels of capability to mitigate and deal with the cyclone hazard. The model is presented here in a simplified form as its development is evolving and ongoing.  相似文献   
18.
Environmental problems in China can be divided into two large classes: pollution and destruction of natural environment. Environmental degradation is particularly serious in areas with rapid population growth. In this paper, some of China's major environmental problems, particularly those concerned with land, forests, and continental waters are introduced in order to see how population growth and management have affected these resources over the past few decades. It is also explained how the Chinese plan to cope and eventually solve these problems.  相似文献   
19.
The Henze precipitate, a peculiar blue-green microparticulate obtained by lysis of the blood cells of the ascidian Phallusia mammillata (Protochordata), was investigated with atomic force microscopy (AFM), scanning electron microscopy (SEM) and X-ray microanalysis. The precipitate was collected from the Henze solution, an unstable red-brown product obtained by treating blood with distilled water, whose degradation yields a characteristic blue-green product. The microparticulates measured 50–100 µm in diameter and appeared irregular in shape. SEM examination showed smooth, roughly round boundaries. The microparticulate surface examined with AFM appeared as an irregular matrix formed by 70–320-nm-wide mammillate composites, including and embedding small (500–800 nm wide) crystal-like multilayered formations. X- ray analysis showed that the elements present in these same precipitates were mainly C, Si, Al and O. The microparticulate composition appeared close to those of natural waxes or lacquers, embedding amorphous silicates and/or other Si–Al components. The unusual occurrence of Si in ascidian blood and its role are discussed.  相似文献   
20.
In Acromyrmex octospinosus leaf-cutting ants the metapleural glands produce an array of antibiotic compounds that serve as a general defence against unwanted microbes on the cuticle. Leaf-cutting ants also grow mutualistic Pseudonocardiaceae bacteria on their cuticle that produce antibiotics controlling a microfungal parasite of their fungus gardens. Interaction between this bacterium and gland secretion therefore seems unavoidable. We document the typical development of bacterial growth on the cuticle of young major workers, show that growth starts a few days after eclosion, and that the maximal cover is reached after 2–3 weeks and gradually declines when workers mature. Experimental closure of the metapleural glands had no effect on the initial exponential growth phase of the bacterium, but significantly reduced the cover during the decline phase. The age-dependent abundance of the bacterium and its partial dependence on metapleural gland secretion support the hypothesis that the abundance of this mutualist is actively regulated.  相似文献   
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