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311.
The content of main chemical components (total nitrogen and carbon, soluble and polymeric sugars, organic acids, and mineral substances) were studied in the leaves of 73 boreal plant species with different types of Grime–Ramenskii strategies. The type of ecological strategy was demonstrated to be related to the chemical composition of the leaf, with the substances studied falling into two groups. The concentrations of the substances belonging to the first group (nitrogen, organic acids, and mineral substances) were minimum in stress-tolerant and maximum in ruderal species. With respect to the type of strategy, these concentrations increased in the following series: S C R. Conversely, the concentrations of the substances of the second group (carbon and soluble sugars) decreased in this series. The nitrogen concentration and the carbon-to-nitrogen concentration ratio in leaves may be used for identifying the types of strategies. 相似文献
312.
This paper analyzes the human–nature interaction in a village in rural South Africa. It discusses preconditions, perceptions,
and consequences of natural resource use, and places these findings into a regional and historical context. Applying an interdisciplinary
perspective, the study uses interviews, questionnaires, remote sensing, and participatory mapping to analyze land cover changes
and local perceptions of the environment. The study area is located in a former homeland (Transkei), a setting where well-recorded
conflicts in the human–nature sphere have previously been triggered by population pressure, apartheid policies, and other
historical, political, and social reasons. A small-scale and subjective conceptualization of environmental security is used
as an approach to analyze local livelihood strategies in a selected village. The results indicate that the environment is
not the highest priority in local survival strategies. Instead, formal and informal jobs and governmental grants are the most
important security strategies. There are thus no major conflicts resulting from the interaction between the local population
and the natural resources in this specific area. Explanations to this pattern can partly be found in historical contexts,
which include apartheid policies, re-localizations, and a system of migrant labor. The study also suggests that general truths
about a region such as Transkei might be misleading in specific localities. For relevant and successful environmental management
and development planning however, it is crucial that decision-makers be able to get a clear picture of local situations and
adjust their plans accordingly. 相似文献
313.
魏玉金 《中国环境管理干部学院学报》2005,15(3):48-51
在环境纠纷的非诉讼解决方面,我国虽然已有运用各种非诉讼纠纷解决方式来处理环境纠纷的实践,但在立法方面以及运作方式上仍然不完善,通过对该机制的各种程序进行分析和阐述,提出我国在环境纠纷解决中运用非诉讼解决机制进行重构. 相似文献
314.
我国气象灾害的分类与防灾减灾对策 总被引:2,自引:2,他引:2
本文根据气象灾害特征、致灾因子和天气现象类型,将我国的气象灾害划分为7大类20种.为了适应科学防灾减灾和社会、经济快速发展的需求,必须加快大气监测、信息加工和气象灾害预警能力为主要内容的气象现代化建设;加强气象灾害的机理研究;制定科学防灾减灾对策. 相似文献
315.
This paper describes a heuristic model which helps to relate a developing nation's environmental risk to the level of sophistication appropriate in adjusting management strategy to dealing with environmental hazards. The model takes into account three factors: the degree of risk, the stage of economic growth, and the sophistication of adjustment. The interrelationship of these factors is examined, and the role of international cooperation in establishing strategies is outlined. 相似文献
316.
I. F. Salkin 《Journal of Material Cycles and Waste Management》2003,5(1):0009-0012
The limited scientific information about infectious waste, and the heightened public awareness of this special component
of the waste stream, have contributed to the implementation or strengthening of the regulations in this area. This paper proposes
a general working definition of infectious waste, and describes the systems used to limit its potential occupational and public
health impacts. Although incineration and autoclaving are the most widely used methods of treating infectious waste, the introduction
of more stringent air-quality standards for incinerators, and the inherent limitations to the application of autoclaves, have
created a demand for other methods of processing this segment of the solid and liquid waste streams. These alternative technologies
use one or more of the following methods: (1) heating the waste to a minimum of 90–95°C; (2) exposing the waste to suitable
chemicals; (3) subjecting the waste to heated chemicals; (4) irradiating the infectious waste with ionizing sources. The advantages
and disadvantages of each of these alternative forms of treatment are discussed in this paper.
Received: April 22, 2002 / Accepted: October 14, 2002 相似文献
317.
Management of natural environment sites is becoming increasingly complex because of the influx of urbanized society into wildland areas. This worldwide phenomenon impacts a wide range of countries. In southern California ethnicity is often a major factor influencing recreation site use and behavior at sites in the wildland-urban interface. This study investigated the role of ethnicity and race on the use patterns, perception of environment, and recreation behaviors at an outdoor recreation site visited by an ethnically diverse population. Two research questions were asked: (1) What ethnic groups engage in outdoor recreation at this site, and (2) what differences can be assigned to these various groups? Data were collected from 250 recreationists during 1991. Three major ethnic groups were identified, and statistically significant differences were found in the importance of site attributes, activity participation, and in preferred and actual communication channels. Management implications and strategies based on group differences are discussed. 相似文献
318.
旅游用地是一种特殊的土地资源类型,一直没有得到应有的重视。在实际利用中存在着许多突出问题,如旅游景点的土地利用规划与旅游规划不协调,旅游用地中的景观设计的人为性,旅游用地资源环境污染和破坏,旅游用地中的产权关系混乱,以及打生态旅游牌搞房地产开发等。研究提出了加强旅游用地立法,做好土地规划与旅游规划,对旅游用地进行估价,实行用地来源的多途径化与统一管理等对策。它是一项探索式研究,具有开创性,旨在为旅游资源的可持续发展做初步探讨。 相似文献
319.
320.
The United Nations Population Fund (UNFPA) coordinated efforts to integrate RH into contingency planning for the 2003 Iraq crisis and the 2003 regional response for displaced populations in West Africa. Using UNFPA's network of country offices in the Middle East, staff developed logistics plans, conducted workshops and pre-positioned RH supplies. Though refugee movements did not occur, the contingency planning enhanced the response capacity of UNFPA offices and made it possible to rapidly provide assistance inside Iraq. In West Africa, multi-country workshops and follow-up resulted in country-level and regional action plans useful during the renewed crises of 2003; scarce funding, however, limited their full implementation. UNFPA's experiences show that contingency planning requires committing resources for crises, some of which will not occur; new staff skills; and follow-up. Moreover, RH is considered by some to be additional to the core elements of contingency planning. RH's political sensitivity, particularly with certain donors, further complicated integrated planning. 相似文献