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721.
自然灾害综合预报和年度会商   总被引:4,自引:2,他引:2  
本文从系统论的观点和高度上分析了自然灾害综合预报的必要性和重要意义,同时结合陕西省近几年开展年度综合会商的实际和体会,就自然灾害综合预报和年度会商的具体内容、形式和方法等建设问题进行了讨论,最后提出了今后进一步改进会商质量、提高预报水平的建议。  相似文献   
722.
申曙光  叶谦吉 《灾害学》1992,7(1):18-22
本文从灾害的产生与灾害概念的发展、灾害的成因与过程、灾害的后果等多个方面论证和论述了灾害的生态经济性质。灾害生态经济性质的揭示为开展各类灾害的系统总体研究—灾害的生态经济研究提供了理论依据。  相似文献   
723.
攀西地区实施退耕和天保工程的问题及对策   总被引:4,自引:1,他引:3  
攀西地处长江上游,在西南地区乃至全国的可持续发展战略中具有重要地位,目前生态退化严重。论述了攀植实施退耕还林还草和天然林保护工程的问题,如产业结构的单一性和脆弱性及地方财政的弱势地位造成对森林依赖性砍伐,法律法规等各项具体配套措施不到位,利益分享补偿机制等制度建设落后于实践,群众的落后思维方式和发展观念难以摒除等都使工程实施初期的经济效益不明显,当地群众脱贫又返贫,社会矛盾激化等。对此提出了相关对策,即区分当前和长远两个层次,在当前主要依靠国家加大财政转移支付和吸引民间投资,加强资金监督管理,强化普法执法,加强现有技术措施的推广应用等;远期内,完善基础设施,发展水电,旅游等资源商品型替代产品,重视农村科教文卫普及,摒除陈规陋习,控制人口增长,树立“环境容量/土承载力”的可持续发展意义.等  相似文献   
724.
The problem of management of industrial residuals can be reduced through a rational system for siting and planning major industrial facilities. In the United States, Wyoming has moved in the direction of establishing a one-stop permitting system that provides important information for air and water quality planning and solid waste management with a minimum of regulatory overlap. This paper describes Wyoming's Industrial Development Information and Siting Act of 1975 and suggests ways in which the Wyoming permitting system can be improved and applied elsewhere.  相似文献   
725.
The USA is heavily dependent on foreign sources for supplies of key materials essential to the nation's defence and to the operation of its vital industries. For example, it depends on foreign sources for 22 of the 27 metals considered vital to the country's economy. A public workshop on Conservation and Substitution Technology for Critical Materials was held from 15–17 June 1981 at Vanderbilt University, Nashville, Tennesse, to examine national policies towards resolving the supply problems associated with chromium, cobalt, tantalum and titanium.  相似文献   
726.
Biomass and productivity were compared in two plantations and in one stand of natural regeneration on similar sites in a premontane moist forest region of Puerto Rico. While initial growth rates of plantation species were higher, after four decades productivity of the natural regeneration plots was equal to or greater than productivity of the plantations. For the first 44 years, aboveground biomass of natural regeneration increased at an average annual rate of 3.8t·ha–1·yr–1, but the last year of the study it was 14.7t·ha–1. Biomass increment of a pine plantation averaged between 8 and 10.5t·ha–1·yr–1 except for one year when the rate was much lower, possibly because of hurricane damage. A tropical hardwood plantation averaged close to 4t·ha–1·yr–1 for 41 years. It is suggested that in countries where funds for land reclamation are limited, intensive plantations may not always be the best strategy. Natural regeneration or shelterbelt plantations may be suitable alternatives.  相似文献   
727.
可持续发展与灾害类型的分析研究   总被引:3,自引:1,他引:2  
王占礼 《灾害学》1999,14(1):85-90
在人口与经济快速增长的条件下,人与自然关系的不协调发展导致了灾害的频繁发生,为了拓展、良化人类生存空间,对灾害的类型与危害进行了系统分析,并提出了防灾减灾的措施.  相似文献   
728.
Morgan R 《Disasters》1986,10(1):30-34
This article discusses the initiative of the Government of Botswana in formulating and introducing a programme to assist recovery in rural areas after the present drought period as an important aspect of the national development effort. It examines the process by which this Post Drought Recovery Programme was arrived at, its limitations, the extent of its appropriateness to longer-term factors which render rural households more vulnerable to drought, and suggests conclusions which may be drawn to inform the design of similar programmes elsewhere.  相似文献   
729.
本文根据1951~1995年我国336个站逐旬降水量资料,采用服从皮尔逊Ⅲ型分布的旱涝Z指数,分析了40多年来我国夏季风活跃期的旱涝事实,并对旱涝灾的影响进行了评述  相似文献   
730.
Mercury (Hg) is among the most concerned contaminants in the world. It has three major chemical forms in the environment, including Hg0, Hg2 +, and methylmercury (MeHg). Due to their differences in toxicity, mobility, and bioavailability, speciation analysis is critical for understanding Hg cycling and fate in the environment. SnCl2 reduction-atomic fluorescence spectrometry detection is the most commonly used method for analyzing inorganic Hg. However, it should be noted that MeHg may also be reduced by SnCl2, which would result in the overestimation of inorganic Hg. In this study, the reduction of MeHg by SnCl2 in both de-ionized (DI) water and four natural waters was investigated. The results showed that MeHg could be reduced by SnCl2 in DI water whereas this reaction was hard to occur in tested natural waters. By investigating the effects of water chemical characteristics (dissolved organic matter, pH and common anions and cations) on this reaction, SO42 ? was identified to be the dominant factor prohibiting SnCl2 induced MeHg reduction in natural waters. SO42 ? in natural waters was evidenced to be reduced to S2 ? by SnCl2 and the generated S2 ? can complex with MeHg to form MeHgS? which is hard to be reduced by SnCl2. Findings of this study indicate that the effect of MeHg reduction by SnCl2 on inorganic Hg analysis is negligible in natural waters; however, at simulated experimental systems without SO42 ?, SO42 ? should be added as protecting agents to prevent MeHg reduction when analyzing inorganic Hg if it would not cause any other unwanted effects.  相似文献   
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