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361.
362.
Foreword Inglobalview ,droughtdisasterisregardedasthemostserioustypeofnaturaldisasterintheworld ,whichhascausedthewidestrangeofeffectsandthebiggesteconomiclosses .Se veredroughtsmainlyoccurinAfrica ,India ,China ,formerSovietUnion ,NorthAmerica ,andAustralia,accountingforalmosthalfofcountriesintheworld .Droughtdisasteroccursfre quentlyinChina ,withwiderangeofinfluence ,whichisthemostseriousmeteorologicaldisas ter ,causingeconomiclossesinagriculture .Fromthe 50’stothe 80’sinthe 2 0thcent… 相似文献
363.
Foreword Asoneofthethreegreatdiscoveriesin 1 970s ,thefractaltheoryhasbeenwidelyappliedinmanyfieldsconcerningthesciencesofnatureandthehumanities .Atpresent ,thefractaltheoryhasbeenappliedintherelatedanalysisofwatersystemordisaster .However ,thestud iesonnatureofrelationshipbetweenthewholewatersysteminChinaanddisasterfractalanaly sisarestillintheirinitialperiod .Thepaperpresentsafractaldimensionof 7drainagebasinsandthefloodinChinaaswellastheirpossiblerelations .Itishopedthatthepaperwouldbehe… 相似文献
364.
在"十一五"即将起步之时,在全面建设小康社会的关键时期,国务院发布了<关于落实科学发展观加强环境保护的决定>(以下简称<决定>),这是深入贯彻十六届五中全会精神,落实科学发展观,构建社会主义和谐社会,指导我国经济、社会与环境协调发展的一份纲领性文件.深入学习贯彻<决定>,对于广泛调动全社会力量,加快推进环保事业发展,实现全面建设小康社会的宏伟目标将产生巨大的推动作用. 相似文献
365.
现在全球的职业种类正在改变,这些改变在职业安全健康(劳动保护)方面给我们提出了新的挑战。这些挑战要求我们找出新的解决方法,这一切都是因为全球经济一体化发展促使我们拥有共同的利益和需求。我们的解决方案必须充分考虑差别甚 相似文献
366.
Cadmium solubility and sorption in an arable clay loam soil that had received sewage sludge for 41 years were compared to an unsludged control in batch studies. Soil pH dominated Cd sorption, explaining >92% of the variation in Kd values in both treatments. At any pH, Cd sorption was apparently slightly but significantly (p < 0.05) smaller in the sludge-amended soil compared to the control, even though the organic carbon content was 70% larger and the ammonium oxalate-extractable iron content was roughly doubled. Correction for dissolved organic carbon (DOC) complexation with the speciation model WHAM reduced the difference in sorption between treatments, but the sludged soil still had significantly smaller Kd values (p < 0.01). Batch equilibrations without addition of Cd showed that there was no significant difference in the solubility of "native" cadmium (defined as EDTA-extractable Cd) in sludged and control soils. The reason for the lack of increase in Cd sorption in the sludge-amended soil has not been established, but it may be due to competition for sorption sites on humic compounds with sludge-derived Fe and trace metals such as zinc. The fact that the pyrophosphate-extractable (i.e., organically associated) iron content was seven times larger in the sludged soil provides some supporting evidence for this hypothesis. 相似文献
367.
Hackett AG Gustafson DI Moran SJ Hendley P van Wesenbeeck I Simmons ND Klein AJ Kronenberg JM Fuhrman JD Honegger JL Hanzas J Healy D Stone CT 《Journal of environmental quality》2005,34(3):877-889
A surface drinking water monitoring program for four corn (Zea mays L.) herbicides was conducted during 1995-2001. Stratified random sampling was used to select 175 community water systems (CWSs) within a 12-state area, with an emphasis on the most vulnerable sites, based on corn intensity and watershed size. Finished drinking water was monitored at all sites, and raw water was monitored at many sites using activated carbon, which was shown capable of removing herbicides and their degradates from drinking water. Samples were collected biweekly from mid-March through the end of August, and twice during the off-season. The analytical method had a detection limit of 0.05 microg L(-1) for alachlor [2-chloro-N-(2,6-diethylphenyl)-N-(methoxymethyl)-acetamide] and 0.03 microg L(-1) for acetochlor [2-chloro-N-(ethoxymethyl)-N-(2-ethyl-6-methylphenyl)-acetamide], atrazine [6-chloro-N-ethyl-N'-(1-methylethyl)-1,3,5-triazine-2,4-diamine], and metolachlor [2-chloro-N-(2-ethyl-6-methylphenyl)-N-(2-methoxy-1-methylethyl)-acetamide]. Of the 16528 drinking water samples analyzed, acetochlor, alachlor, atrazine, and metolachlor were detected in 19, 7, 87, and 53% of the samples, respectively. During 1999-2001, samples were also analyzed for the presence of six major degradates of the chloroacetanilide herbicides, which were detected more frequently than their parent compounds, despite having higher detection limits of 0.1 to 0.2 microg L(-1). Overall detection frequencies were correlated with product use and environmental fate characteristics. Reservoirs were particularly vulnerable to atrazine, which exceeded its 3 microg L(-1) maximum contaminant level at 25 such sites during 1995-1999. Acetochlor annualized mean concentrations (AMCs) did not exceed its mitigation trigger (2 microg L(-1)) at any site, and comparisons of observed levels with standard measures of human and ecological hazards indicate that it poses no significant risk to human health or the environment. 相似文献
368.
Geneletti D 《Journal of environmental management》2005,76(3):255-262
One of the main objectives of landscape ecology is to orient land-use planning by providing indications of optimal ecosystem patterning to support nature conservation. A frequent limitation to the practical use of the findings of landscape ecological studies is that they tend to focus on the identification and computation of indicators rather than on their interpretation and assessment. This paper presents and discusses the use of a methodology to formalise expert opinion through the elicitation of multi-attribute value functions. In particular, the value functions aim at assessing spatial indicators so as to provide an overall judgment of the viability of different ecosystem patches. The result consisted of the ranking of the ecosystems according to their degree of viability and therefore their suitability for nature conservation. The method of formalising expert opinion and knowledge complements traditional analyses based on the measurement of spatial ecological indicators. 相似文献
369.
This study was conducted to investigate microbial organisms that can be used for preventing clogging in drip irrigation systems caused by biological factors. A total of 25 fungi isolate and 121 bacterial strains were isolated from water samples collected from drip irrigation systems in tomato greenhouses in the eastern Anatolia region of Turkey in the spring season of 2001. Biological clogging of emitters in a model drip irrigation system was experimentally caused by application of the microorganisms (fungi and bacteria) isolated in the study. Three antagonistic bacterial strains in the genus Bacillus spp (ERZ, OSU-142) and Burkholdria spp (OSU-7) were used for treatment of biological clogging of the emitters. The results showed that the antagonistic bacterial strains tested have the potential to be used as anti-clogging agents for treatment of emitters in drip irrigation system. This is the first study that demonstrated that antagonistic microorganisms can be utilized for treatment of clogging in drip irrigation systems. 相似文献
370.
Science in the public process of ecosystem management: lessons from Hawaii, Southeast Asia, Africa and the US Mainland 总被引:1,自引:0,他引:1
Gutrich J Donovan D Finucane M Focht W Hitzhusen F Manopimoke S McCauley D Norton B Sabatier P Salzman J Sasmitawidjaja V 《Journal of environmental management》2005,76(3):197-209
Partnerships and co-operative environmental management are increasing worldwide as is the call for scientific input in the public process of ecosystem management. In Hawaii, private landowners, non-governmental organizations, and state and federal agencies have formed watershed partnerships to conserve and better manage upland forested watersheds. In this paper, findings of an international workshop convened in Hawaii to explore the strengths of approaches used to assess stakeholder values of environmental resources and foster consensus in the public process of ecosystem management are presented. Authors draw upon field experience in projects throughout Hawaii, Southeast Asia, Africa and the US mainland to derive a set of lessons learned that can be applied to Hawaiian and other watershed partnerships in an effort to promote consensus and sustainable ecosystem management. Interdisciplinary science-based models can serve as effective tools to identify areas of potential consensus in the process of ecosystem management. Effective integration of scientific input in co-operative ecosystem management depends on the role of science, the stakeholders and decision-makers involved, and the common language utilized to compare tradeoffs. Trust is essential to consensus building and the integration of scientific input must be transparent and inclusive of public feedback. Consideration of all relevant stakeholders and the actual benefits and costs of management activities to each stakeholder is essential. Perceptions and intuitive responses of people can be as influential as analytical processes in decision-making and must be addressed. Deliberative, dynamic and iterative decision-making processes all influence the level of stakeholder achievement of consensus. In Hawaii, application of lessons learned can promote more informed and democratic decision processes, quality scientific analysis that is relevant, and legitimacy and public acceptance of ecosystem management. 相似文献