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81.
园林树木栽培学是一门实践性很强的有关园林绿化领域的专业课、必修课.1995年以来,本人在园林树木栽培学各论教学中尝试重点讲解、课堂点评的教学方法,取得了较好的教学效果.  相似文献   
82.
An evaluation of coastal landscape of pine forest in Greece by summer visitors of various nationalities was carried out. The visual preferences for a set of landscape, represented in photographs, expressed by these various nationality groups were compared. The subjects used in this research came from Greece, Germany, Italy, France, Great Britain, Austria, Yugoslavia, and Scandinavian countries. The findings show that there is an agreement over the basic preference, but, nevertheless, there are differences of opinion between the nationality groups that might be attributed to cultural influences and the effect of being familiar with their own environments. Since coastal landscape plays an important role in the tourist industry, these findings could be very useful to policy-making agencies.  相似文献   
83.
The study attempts to separate the effects of forest fragmentation related to landscape (patch area, isolation) and habitat (altitude, vegetation structure) on bird community composition in a mountain pine forest. Bird composition was related, using a multivariate approach (canonical correspondence analyses), to either habitat or to landscape, eliminating the effect of habitat statistically. Bird composition and species richness varied with patch area and isolation from large pine stands, but this effect could be assigned principally to variation in vegetation structure and altitude. Another effect, that of increasing occurrence and numbers of Anthus trivialis with decreasing distance to nearest low-altitude forest, could be assigned to both habitat (grass cover) and landscape (connectivity effects). Management implications are drawn from the results.  相似文献   
84.
The paper attempts to conceptualise a range of problems arising from project appraisals. The author presents some general considerations concerning the role of social appraisal in territorial planning, the theoretical weaknesses of cost‐benefit analysis in assessing the effects of projects on territorial resources and some questions relating to assessment methodologies and the welfare foundations of social appraisal within planning practices. The author moves away from evaluation as a technical process towards one which also incorporates ‘practical’ knowledge in a process of argumentation.  相似文献   
85.
This paper presents an integrated system for the assessmentof technical and non-technical measures that are putforward in order to reduce air pollution levels in urbanareas. In contrast to the majority of the currentlyemployed assessment tools, this system allows for theevaluation of any proposed air pollution control measure interms of its combined impact on air quality and socialwelfare, by correlating the environmental and economicaspects of alternative air pollution abatement solutions.Based on the multi-pollutant, multi-effect concept, thesystem presented aims in providing policy-makers with areliable tool for the objective assessment of the mostcost-effective packages of measures, the latter beingallocated according to the particular features and needs ofthe areas examined.  相似文献   
86.
ABSTRACT: Bringing water from Colorado River via the Central Arizona Project was perceived as the sole solution for Tucson Basin's water problem. Soon after Central Arizona Project's water arrived in Tucson in 1992, its quality provoked a quarrel over its use for potable purposes. A significant outcome of that quarrel was the enactment of the 1995 Proposition 200. The Proposition 200 precludes the use of Central Arizona Project's water for potable purposes, unless it is treated. Yet, it encourages using it for non‐potable purposes and for replenishing the Tucson aquifer through recharge. This paper examines the economic issues involved in utilizing Central Arizona Project's water for recharge. Four planning scenarios were designed to measure and compare the costs and benefits with and without Central Arizona Project's water recharge. Cost‐benefit analysis was utilized to measure recharge costs and benefits and to derive a rough estimate of cost savings from preventing land subsidence. The results indicate that the institutional requirements can be met with Central Arizona Project's water recharge. The economic benefits from reducing pumping cost and saving groundwater are not economically significant. Yet, when combining the use of Central Arizona Project's water for recharge and non‐potable purposes, it demonstrates positive net economic benefits.  相似文献   
87.
污水的人工湿地系统处理技术   总被引:9,自引:4,他引:9  
黄时达  冷冰 《四川环境》1993,12(2):48-51
本文通过了人工湿地系统处理技术及其发展、应用的综述介绍,并以深圳白泥坑人工湿地处理系统工程与二级生化污水处理厂相比较。结果表明,用人工湿地系统处理污水具有投资少,耗能低,运行简便等优点,提出研究、推广应用湿地系统技术处理污水的建议,可供环境保护科研及管理人员参考。  相似文献   
88.
吴志文 《四川环境》1999,18(2):42-45
运用川北广元历年飞播成效调查以及固定标准地观测的结果,结合笔者从事飞播造林技术与管理工作的经验,得出:飞播造林是速度快、省劳力、投资少、成本低、效益高的造林方式,推广飞机播种造林是绿化川北山地,迅速治理流域生态环境和实现山区经济可持续发展的有效措施  相似文献   
89.
利用煤矸石制备低环境负荷型水泥的研究   总被引:3,自引:0,他引:3  
煤矸石是我国排放量最大的工业废渣之一,破坏生态环境,不利于可持续发展。本文分析与研究了煤矸石的综合利用现状,着重探讨了煤矸石在我国水泥工业中的应用,并从材料学、热学和环境学等交叉学科入手研究了利用煤矸石生产低环境负荷型水泥的控制理论与技术及其社会经济效益。  相似文献   
90.
景观生态学在建设项目生态环境影响评价中的应用   总被引:13,自引:0,他引:13  
田红  何晓静 《四川环境》2003,22(4):13-15,22
景观生态学目前是国家环境保护总局《非污染生态影响评价技术导则》引入的概念框架和理论方法。本文通过景观生态学在不同性质建设项目中的运用分析,进行了一定的尝试,更加希望在今后建设项目生态环境影响评价工作中得到修正和完善。  相似文献   
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