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151.
集宁-二连浩特铁路干线防护林土壤的理化特性   总被引:2,自引:0,他引:2  
应用经典统计学方法,对集宁-二连浩特铁路沿线防护林土壤理化特性进行了研究. 结果表明,与林带外相比,林带内土壤容重显著减小,影响其容重大小的主要因素是由林带内外和不同林带类型差异造成的. 林带内表土层物理性砂粒所占比例显著增大,物理性黏粒所占比例降低,心土层、底土层无明显变化. 土壤水分在垂直方向呈先增后降趋势,时间变化表现为减小趋势,林带内土壤含水量以及水贮量损失均显著增大. 林带内表土层有机质、速效钾含量显著增加,心土层、底土层无明显变化. 全氮、速效磷含量无明显变化. 结合不同林带土壤理化性质分析表明,在草原铁路沿线造林工作中,如果立地条件允许,适宜造锦鸡儿林带和榆树林带,锦鸡儿林带起固沙作用,榆树林带起防风作用.   相似文献   
152.
Bob Baulch 《Disasters》1987,11(3):195-204
The traglic recent events in Ethiopia and other parts of Africa have again foccussed attention on the different anaytical approaches to the problems iof famine. Perhaps the most important analytical contribution to this field has been Sen's "entitlements approach." One of the case studies Sen used to articulate this approach was of the 1972–1973 famine in Wollo Province, Ethiopia. This article provides a provisional assessment of the famine process in the Wollo during 1982–1985 to set against the analysis by Sen of the earlier famine. Some striking contrasts are revealed.  相似文献   
153.
建立汕头港溢油应急反应体系的设想   总被引:2,自引:1,他引:2  
庄小洪 《交通环保》1999,20(3):38-40
根据汕头港水域状况及溢油事故概况,阐述了建立汕头港溢油应急反应体系的必要性,并提出了建立这一体系的设想。  相似文献   
154.
Introduction: Beach and patio umbrellas may cause injury. There is limited published information on injuries due to beach and patio umbrellas. This study sought to describe beach and patio umbrella injuries reported to United States emergency departments (EDs). Method: An analysis was performed of beach and patio umbrella injuries using data from the National Electronic Injury Surveillance System during 2000–2019. Results: An estimated 5,512 beach umbrella injuries and 7,379 patio umbrella injuries were identified. The patient was age 40 years or older in 62.1% of the beach umbrella and 65.1% of the patio umbrella injuries. The patient was female in 68.0% of the beach umbrella and 66.9% of the patio umbrella injuries. Wind was reported involved in 50.6% of the beach umbrella and 27.5% of the patio umbrella injuries. The most frequently reported injuries with beach and patio umbrella injuries, respectively, were laceration (44.0% vs 33.0%), contusions or abrasions (19.8% vs 19.0%), and internal organ injury (16.6% vs 17.0%) and most often affected the head/neck (60.2% vs 44.0%) and upper extremity (16.3% vs 30.1%). Conclusions: The majority of patients with beach and patio umbrella injuries treated at EDs were age 40 years or older and most patients were female. For both types of umbrella injury, the most frequently reported injury was laceration followed by contusions or abrasions and internal organ injury, and the body part with the highest proportion of injuries was the head/neck followed by the upper extremity. Practical Applications: Persons should use sturdier models of beach or patio umbrella, use a rocking motion to dig into the sand and secure the beach umbrella with a metal anchor and screws, add weight to the bottom of the umbrella, and tilt the umbrella into the wind. Policy-makers should educate the public about the potential dangers of beach and patio umbrellas.  相似文献   
155.
徐州市三环西路硝基苯泄漏事故应急监测案例分析及研究   总被引:1,自引:1,他引:0  
2006年4月徐州市三环西路发生一起硝基苯泄漏事故。通过对该环境应急监测案例的分析与研究,认识到我们在突发性污染事故环境监测与管理方面的不足,提出了加强与改进的措施,使环境应急监测系统更完善。  相似文献   
156.
This study examines the normative functioning of the volcano warning system on the Island of Hawaii. The research seeks to identify the combination of factors, both environmental and social, which allows the system to operate with success. On the basis of the findings, several recommendations are offered for improving environmental hazard warning systems.  相似文献   
157.
Summary. Oviposition site selection of herbivorous insects depends primarily on host plant presence which is essential for offspring survival. However, parasitoids can exploit host plant cues for host location. In this study, we hypothesised that herbivores can solve this dilemma by ovipositing within high plant diversity. A diverse plant species composition might represent an ‘infochemical shelter’, as a potentially complex volatile blend can negatively affect the host location ability of parasitoids. We examined this exemplarily for the egg-laying response of the generalist leaf beetle, Galeruca tanaceti, in relation to (1) host plant availability and (2) plant species diversity in the field. Further, we investigated the effect of odours from mixed plant species compositions on (3) leaf beetle oviposition site selection and on (4) the orientation of its specialised egg parasitoid, Oomyzus galerucivorus. In the field, egg clutch occurrence was positively related to the presence and quantity of two major host plants, Achillea millefolium (yarrow) and Centaurea jacea, and to the number of herbaceous plant species. In two-choice bioassays, female beetles oviposited more frequently on sites surrounded by an odour blend from a diverse plant species composition (including yarrow) than on sites with a pure grass odour blend. In the presence of yarrow odour and an odour blend from a diverse plant mixture (including yarrow) no difference in the oviposition response was recorded. Experienced parasitoid females were attracted to yarrow odours, but showed no response when yarrow odours were offered simultaneously with odours of a non-host plant. In conclusion, it could be shown in laboratory bioassays that the parasitoid responds only to pure host plant odours but not to complex odour blends. In contrast, the herbivore prefers to oviposit within diverse vegetation in the field and in the laboratory. However, the laboratory results also point to a priority of host plant availability over the selection of a potential ‘infochemical shelter’ for oviposition due to high plant diversity.  相似文献   
158.
环境应急监测准备及其保障   总被引:7,自引:0,他引:7  
环境突发性事故应急监测工作包括日常的应急监测准备和应急事故监测两部分内容,做好应急监测日常工作,对于及时、准确、有效地开展应急监测工作十分重要。  相似文献   
159.
Performance of a Lagrangian dispersion model was examined in connection with its dependency on the boundary layer modelling and the input data resolution. The European Tracer Experiment (ETEX) data were used as reference. According to the sensitivity analysis of the model performance, the long-range dispersion model with the sparse input data was not noticeably different from that with the finer resolution data. The assumption of the prescribed constant mixing depth did not largely degrade the prediction results as compared with the simulation results with the temporally changing boundary layer. It is, therefore, concluded that the model is practical, considering the limited input data in the operational mode. However, it was also pointed out that the parameterization for the horizontal and vertical diffusion processes used in the present model enhanced the growth of plume. The improvement of input data resolution in time and space caused further dispersion of tracer deterministically. These resulted in the underestimation of the maximum concentration and the unfocussed concentration distribution map although the mean concentration was predicted fairly well.  相似文献   
160.
For a community to manage hazards successfully, those who are responsible for planning and implementing responses to a disaster threat situation must understand the social and economic realities of populations at risk. A random sample survey of residents in the vicinity of a US Army chemical weapons storage depot in Alabama confirms that those in the lowest quartile of household income (i.e., less than US $25,000 in 1999) differ in important ways from the rest of the sample. Using economic status as a grouping variable resultedin identifying a concentration of individuals with special needs. This group differed significantly from the remainder of the sample as to demographic and attitudinal characteristics, hazard knowledge and concerns, emergency preparedness, and emergency decision-making and their likelihood of taking protective actions. Respondents in the lowest income quartile reported greater restrictions in physical abilities, fewer community contacts, a heightened concern about area hazards, and limited resources for taking preparedness and response actions.  相似文献   
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