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21.
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   
22.
1 IntroductionMercury(Hg)asaglobalpollutanthascausedconcernworldwidesincetheendof 1980s.Itisemittedtotheatmospherefrombothanthropogenicandnaturalsources.Importantsourceoftheformeristhedischargefrom productionanduseofHgaswellasthecombustionoffossilfuels(Nri…  相似文献   
23.
Large scale dairy operations are common. In many cases the manure is deposited on a paved surface and then removed with a flushing system, after which the solids are separated, the liquid stored in ponds, and eventually the liquid applied on adjacent crop land. Management of liquid manure to maximize the fertilizer value and minimize water quality degradation requires knowledge of the interactive effects of mineralization of organic N (ON) to NH4+, crop uptake of mineral N, and leaching of NO3 on a temporal basis. The purpose of the research was to use the ENVIRO-GRO model to simulate how the amount of applied N, timing of N application, ON mineralization rates, chemical form of N applied, and irrigation uniformity affected (1) yields of corn (Zea mays) in summer and a forage grass in winter in a Mediterranean climate and (2) the amount of NO3 leached below the root zone. This management practice is typical for dairies in the San Joaquin Valley of California. The simulations were conducted for a 10-year period. Steady state conditions, whereby an equivalent amount of N applied in the organic form will be mineralized in a given year, are achieved more rapidly for materials with high mineralization rates. Both timing and total quantity of N application are important in affecting crop yield and potential N leaching. Major conclusions from the simulations are as follows. Frequent low applications are preferred to less frequent higher applications. Increasing the amount of N application increased both the crop yield and the amount of NO3 leached. Increasing irrigation uniformity increased crop yields but had variable effects on the amount of NO3 leached. A winter forage crop following a summer corn crop effectively reduced the leaching of residual soil N following the corn crop.  相似文献   
24.
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   
25.
本文以呼市发电厂废水、粉尘和灰场污染治理为例,研究制定发电厂粉煤灰综合治理与回收利用技术方案、旧灰场的生态工程建设和冲灰水的回收利用方案,通过污染物治理,废水的利用率达到85%,粉煤灰处理后的产草量和年利用率为98%,灰场的植被覆盖度达到97%,通过治理使发电厂的污染物排放量减少,废弃物资源得以利用,灰场变成环境优美的生态旅游区,为我国电厂的治理工作提供一个切实可行的科学依据。  相似文献   
26.
介绍了长岭炼油化工股份有限公司循环冷却水处理技术开发和管理的经验,分析了取得的经济效益。  相似文献   
27.
为了对大气环境监测点进行优化选择 ,以大气质量分级标准为训练样本 ,构造BP网络进行训练 ,用训练好的BP网络对某地的大气环境监测采样点进行了优选 ,并与物元分析法优选结果进行比较。结果表明 ,BP网络用于环境测点优选具有较好的客观性和应用性  相似文献   
28.
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   
29.
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   
30.
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