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81.
梁隆彪 《中国环境管理干部学院学报》2004,14(4):85-86,105
通过对医疗废物的危害和相关处理技术等问题的研究,提出枣庄市医疗废物处理对策的研究方案,为建立枣庄市医疗废物集中处理中心提供参考,可作为政府及相关业务主管部门的决策依据。 相似文献
82.
83.
Different criteria have been proposed for the rapid ecological evaluation of wooded areas. It is difficult, however, to determine the criteria most likely to yield results similar to those that would be obtained through detailed surveys and exhaustive evaluation. In order to identify such synthetic criteria, data from a detailed evaluation of Montreal Urban Community woodlots were studied with the help of multivariate analysis. This detailed evaluation was undertaken at two levels—woodlot unit and the woodlots themselves—using 16 different criteria.At the woodlot unit level, area and abundance indices of shade intolerant species in the tree layer could be used as synthetic criteria, while at the woodlot level the ecological value of the constituent units stand out as the first synthetic criterion. These results are compared with criteria proposed in the literature, and the use of multivariate analysis in ecological evaluation is briefly discussed. 相似文献
84.
Roger Smith 《Journal of Environmental Planning and Management》1984,27(1):18-22
The British Ecological Society has suggested that computer‐based techniques could be used in the coordination of policies across different land uses in upland planning. This paper looks briefly at one such technique — a linear programming model — and describes its use at a regional scale for the Sedburgh area in north‐west England. The paper concludes with consideration of why such models are not in more common use. 相似文献
85.
Robert H. Montgomery Kenneth H. Reckhow 《Journal of the American Water Resources Association》1984,20(1):43-52
ABSTRACT: With the advent of standards and criteria for water quality variables, there has been an increasing concern about the changes of these variables over time. Thus, sound statistical methods for determining the presence or absence of trends are needed. A Trend Detection Method is presented that provides: 1) Hypothesis Formulation - statement of the problem to be tested, 2) Data Preparation - selection of water quality variable and data, 3) Data Analysis - exploratory data analysis techniques, and 4) Statistical Tests - tests for detecting trends. The method is utilized in a stepwise fashion and is presented in a nonstatistical manner to allow use by those not well versed in statistical theory. While the emphasis herein is on lakes, the method may be adopted easily to other water bodies. 相似文献
86.
微污染水处理技术研究进展 总被引:8,自引:0,他引:8
饮用水水源微污染日益严重,给传统的饮用水处理工艺提出新的挑战.本文阐述了饮用水处理技术的研究进展,包括:强化传统处理工艺、预处理技术、深度处理技术及应用,并给出了各种技术的优缺点. 相似文献
87.
废水厌氧处理工艺的发展 总被引:5,自引:0,他引:5
分析了厌氧工艺的产生和发展的原因,介绍了厌氧反应器的第1代、第2代和第3代反应器的发展内容和过程. 相似文献
88.
Dénis B. Akouwerabou 《Natural resources forum》2023,47(1):42-59
This study shows that farmers in arid and semi-arid land can improve their efficiency if they have access to agricultural extension services. An exhaustive survey was used to obtain data from 423 cotton producers in the arid zones and 144 of wetlands in Burkina Faso. The method of the directional distance function modeling a multi-output technology was used. The results show that cotton farmers in the arid zones are not technically more inefficient than those in wetlands. On average, arid zone producers have a technical inefficiency of 0.056 while that of wetland producers is around 0.052. The agricultural extension, defined as receiving visits and advice from technical agents, is important for producers because it helps farmers choose soil and water conservation techniques and fertilizers adapted to the Agro-climatic conditions of their respective zones. Agriculture extension also helps farmers of the arid zones to reduce their technical inefficiency by advising them to cultivate small agricultural plots. On average, in these zones, the size of an agricultural plot is around 1.03 ha compared to those of wetlands which is about 1.6 ha. 相似文献
89.
系统安全评价方法对比研究 总被引:3,自引:0,他引:3
吴昊 《中国安全生产科学技术》2009,5(6):209-213
安全评价是衡量风险,实现安全生产的重要途径。为了不同的评价目标开发出来的各种安全评价方法都有其针对性和局限性。认清这些方法的优点和缺点有助于系统地运用安全评价方法衡境目标的风险。安全评价软件有助于弥补安全评价方法的不足,并提高安全评价的效率和可靠性。 相似文献
90.
Respiration induced by substrate and bacteria diversity after application of diuron,hexazinone, and sulfometuron-methyl alone and in mixture 总被引:1,自引:0,他引:1
Fabrícia Cristina Dos Reis Valdemar Luiz Tornisielo Bianca A. B. Martins Adijailton José de Souza Pedro Avelino Maia De Andrade Fernando Dini Andreote 《Journal of environmental science and health. Part. B》2013,48(7):560-568
AbstractAfter application, herbicides often reach the soil and affect non-target soil microorganisms, decreasing their population, diversity or affecting metabolic activity. Therefore, laboratory studies were performed to evaluate the effects of diuron, hexazinone and sulfometuron-methyl alone and mixed upon carbon transformation by soil microorganisms in clayey and sandy soils and the effect on bacterial diversity and structure. Control treatment without herbicide application was also performed. Sub-samples from the control and herbicide treatments (10?g – in triplicate) were collected before herbicide application and 7, 14, 28 and 42?days after treatment (DAT), then 1?mL of 14C-glucose solution was applied. The released 14CO2 was trapped in 2?M NaOH solution and the radioactivity was analyzed by liquid scintillation counting (LSC), 12?h after glucose application. The effect of herbicides on bacterial diversity was evaluated by T-RFLP. The experiment was conducted in a complete randomized design. Hexazinone did not affect 14CO2 evolution. Diuron showed a greater 14CO2 evolution in sandy and clayey soil, while sulfometuron-methyl led to an increase in sandy soil, at 42 DAT. A greater evolution of carbon was observed in the treatment with herbicide mixture in sandy soil, compared with the same treatment in clayey soil or control. However, the herbicide mixture application did not affect the soil biological activity measured by the respiration rate induced by substrate. On the other hand, the herbicide mixtures affected the bacterial diversity in both soils, being the strongest effect to diuron and sulfometuron-methyl in clayey soil and hexazinone in sandy soil. 相似文献