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311.
自导式解说系统设计要素研究--以邓小平故居景区为例   总被引:7,自引:0,他引:7  
杨强  杨振之 《资源开发与市场》2004,20(3):227-228,189
以邓小平故居自导式解说系统的实际设计、制作为例,重点研究了自导式解说系统在设计中应当把握的四大要素,并对这四大设计要素在设计过程中的相互关系进行了理论研究和实例分析,指出这四大要素是旅游区设计出高水平、高质量的自导式解说系统的关键核心,从而使自导式解说系统成为提升旅游区整体形象的重要组成部分.  相似文献   
312.
因子分析法在江安河地表水水质评价中的应用   总被引:3,自引:1,他引:3  
道里刚  唐亚  王安 《四川环境》2004,23(2):75-77,83
因子分析法是主成份分析方法的推广和深化,是把原来多个变量化为少数几个综合指标的一种统计方法。本文通过该法对江安河四川大学双流校区段水质进行了评价,结果表明,该水体受到了不同程度的有机物污染,其中非离子氨、阴离子洗涤剂、化学耗氧量,溶解氧所占的负荷最大。  相似文献   
313.
ABSTRACT: Voluntary water transfers through markets have been advocated by many diverse groups as a means to reallocate scarce water supplies in the semi-arid western U.S. Although transfers of water rights have occurred almost since the creation of prior appropriation laws over a century ago, functioning water markets have been very slow to develop and are few in number. The structure, composition, administration and transactions of one of the most well established water markets, shares in the Bureau of Reclamation, Colorado-Big Thompson project, are examined to better understand the institutional and transfer conditions that sustain an active water market. Results from a detailed study of C-BT project records reveal that between 1970 and 1993 there were 2,698 transactions through which over one-third of the project water changed ownership or type of use. Further analysis shows that the transactions involved many individual sellers and categories of buyers with different uses, including agricultural buyers. The transfer activity and efficiency of the C-BT market has lead some to suggest that it be used as a model for other markets. However, because this market has fewer institutional restrictions, a well developed infrastructure and unique market conditions, it will be difficult to transfer this model to other areas without accompanying modifications in water right administration and institutions.  相似文献   
314.
Subsequent to modeling of natural attenuation processes to predict contaminant trends and plume dynamics, monitoring data were used to evaluate the effectiveness of natural attenuation at reducing contaminant concentrations in groundwater at seven fuel-contaminated sites. Predicted and observed contaminant trends at seven sites were compared in order to empirically assess the accuracy of some fundamental model input parameters and assumptions. Most of the models developed for the study sites tended to overestimate plume migration distance, source persistence, and/or the time required for the benzene, toluene, ethyl benzene, and xylenes (BTEX) plumes to attenuate. Discrepancies between observed and predicted contaminant trends and plume behavior suggested that the influence of natural attenuation process may not have been accurately simulated. The conservatism of model simulations may be attributed to underestimation of natural source weathering rates, overestimation of the mass of contaminant present in the source area, and/or use of overly conservative first-order solute decay rates.  相似文献   
315.
This article reports on the technique for the determination of selenium at ppt level and the procedure for the speciation of dissolved selenium in the environmental samples. By combining the high-performance liquid chromatography (HPLC) and a fluorescent detector (FLD), this technique permits the determination of selenium at 0.001 μg/L for Se(IV) and 0.005 μg/L for Se(VI) and the total concentration of selenium for a sample volume of 20 ml. In the speciation procedure, Se(IV) is firstly determined based on the selectivity of 2, 4 - diaminonaphthalene (DAN), the Se (VI) and the total element concentration are determined after reduced to Se(IV) by boiling in 4 mol/L HCl and by digesting in HNO3-HClO4 mixture, respectively. Discussions are given on the relationship between selenium speciation in waters and soil water extract and solution pH, EH and total organic carbon concentration (TOC).  相似文献   
316.
Natura 2000 is a network of natural sites whose aim is to preserve species and habitats of relevance in the European Union. The policy underlying Natura 2000 has faced widespread opposition from land users and received extensive support from environmentalists. This paper addresses the ethical framework for Natura 2000 and the probable moral assumptions of its main stakeholders. Arguments for and against Natura 2000 were analyzed and classified according to “strong” or “weak” versions of the three main theories of environmental ethics – anthropocentrism, biocentrism, and ecocentrism. Weak (intergenerational) anthropocentrism was found to underlie the Natura 2000 network itself and the positions of environmentalists, while strong (traditional) anthropocentrism pervaded the positions of economic developers. Land users seemed to fall somewhere between weak and strong anthropocentrism. The paper discusses the relation between ethics and different attitudes towards Natura 2000, highlighting some of the implications for the network’s ongoing implementation. It is shown that Natura 2000 achieves a strong reversal of the burden of proof from conservation to economic development and land use change under anthropocentrism. It is argued that the alleged theoretical divide between anthropocentrism and non-anthropocentrism in relation to the burden of proof does not seem to hold in practice. Finally, it is predicted that the weak versions of anthropocentrism, biocentrism, and ecocentrism, are likely to converge extensively in respect to nature conservation policy measures.“Charting the depths of law and policy disputes yield an understanding of ethical differences.” Paul B. Thompson (2002, p. 189).  相似文献   
317.
泥沙灾害与泥沙灾害链的分类分级   总被引:7,自引:0,他引:7  
泥沙灾害是泥沙在其侵蚀、输移和沉积运动发生变异时产生的特殊灾害过程,在本质上不同于通常的气象灾害、水灾害、生物灾害和地质灾害.泥沙灾害有着自身的分类系统和分级规则.泥沙灾害可以按照不同的方法进行分类,从而获得不同的分类结果.泥沙灾害链是泥沙灾害过程的主要表现形式之一.基于泥沙灾害特征及泥沙圈与其他圈层相互关系的考虑,从强度和破坏程度两个方面提出了泥沙灾害系统的分类方法,获得了较为完备的泥沙灾害分类.在泥沙灾害分类分级的基础上,还研究了泥沙灾害链的分类分级.泥沙灾害链的分类可以从受灾体和致灾体两个角度采用单指标和分级分类两种方法进行划分,但采用分级分类法更能体现出泥沙灾害链的特点.  相似文献   
318.
环境激素对地球生态系统带来严重威胁.大量难降解环境激素(如多氯联苯、二噁英)危害全球脆弱的生态环境,其直接后果之一就是人类乳腺癌等恶性疾病发病率急剧上升.因此,当今世界各国均十分重视环境激素的环境生物学机理研究.辐射化学作为一门高新技术,在环境激素污染物处理、降解机理与生命科学研究等方面可发挥重要作用,例如:同步辐射可用于直接观测溶液口的雌激素受体ER真实结构,脉冲辐解、激光光解和电子自旋共振用于研究环境激素活性瞬态粒子动力学等等.  相似文献   
319.
固定化细胞小球降解三氟甲苯的特性研究   总被引:2,自引:0,他引:2  
制备了包埋菌种z3的海藻酸钙小球,对固定化细胞小球的机械强度和三氟甲苯的降解率做了研究。通过改变海藻酸钙凝胶组成,添加硅藻土、蛋白质,使用交联剂己二胺、戊二醛等方法,提高了固定化包埋小球交联的密度和机械强度,保持了固定化小球对三氟甲苯的降解活性。扫描电镜显示了包埋小球经过己二胺一戊二醛处理之后,小球的表面结构成网格状,内部网格复杂化,不均匀程度增加。  相似文献   
320.
试论荒漠生态监测的特点和监测指标的确定   总被引:3,自引:0,他引:3  
从监测目的、监测对象、监测指标和监测数据的获取四个方面,论述了进行荒漠生态环境监测工作的特点.从干旱荒漠区自然环境的基本特征和主要生态环境问题及生态环境管理工作的需要出发,提出了在我国开展荒漠生态环境监测工作的监测指标,以供商榷.  相似文献   
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