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1.
缺乏共同语言与理解,是适当利用志愿举措的最重要障碍之一.因此,这份“问答指南”提供了对正在使用的不同类型志愿举措的综述,和一份进一步信息源的清单.联合国环境署利用志愿举措改善公司环境表现的经验可追溯到1992年地球高峰会议以前很久的时候.关于志愿举措...  相似文献   

2.
缺乏共同语言与理解,是适当利用志愿举措的最重要障碍之一.因此,这份"问答指南"提供了对正在使用的不同类型志愿举措的综述,和一份进一步信息源的清单.  相似文献   

3.
缺乏共同语言与理解,是适当利用志愿举措的最重要障碍之一.因此,这份"问答指南"提供了对正在使用的不同类型志愿举措的综述,和一份进一步信息源的清单.  相似文献   

4.
目前我国的英语听力教学中还存在许多问题,英语学习者常常出现看得懂而听不懂的情况.通过分析听力理解的过程以及朗读的本质,过程证明朗读有利于促进语音识别系统的发展和完善,从而有利于提高听力水平.  相似文献   

5.
中小企业越来越期望对他们自已环境和社会影响负起责任来(正如跨国公司所做的那样),理解不同利益相关者的兴趣和要求,并且通过更大的透明度证明自己的行为是负责任的,许多要素既可以阻碍也可以驱动较小企业推动法人环境与社会责任战略的实施,为了克服实施这类战略的障碍,适合小型或中等企业需要的方法才可用,在某此领域,会同跨国公司这个关键的利益相关者团体一起,这方面的促进努力已经行动起来了。  相似文献   

6.
中小企业越来越期望对他们自己环境和社会影响负起责任来(正如跨国公司所做的那样),理解不同利益相关者的兴趣和要求,并且通过更大的透明度证明自己的行为是负责任的.许多要素既可以阻碍也可以驱动较小企业推动法人环境与社会责任战略的实施.为了克服实施这类战略的障碍,适合小型或中等企业需要的方法才可用.在某些领域.会同跨国公司这个关键的利益相关者团体一起,这方面的促进努力已经行动起来了.  相似文献   

7.
相对于传统的"独白式"教学而言,对话教学是一种尊重主体性、体现创造性、追求人性化的教学.提问是课堂教学中实施对话的基本方式,是英语阅读教学重要组成部分.传统的英语阅读课堂存在忽视学生提问和提问的效果等种种问题.从对话教学的视野来看,英语阅读课堂提问应注重开放性、过程性、情境性和探究性,让学生更透彻地读懂文本,从而提高英语阅读理解能力.参11.  相似文献   

8.
联合国环境署技术、工业与经济司(UNEP DTIE)对工业化国家和发展中国家的六个城市的700多位“全球消费者”进行的一项调查突出了目前的消费方式和消费者期望值的相似性。一般来说,消费者(尤其是中高收入人群中的消费者)似乎准备支持引导消费方式实现可持续性的举措,但是,不同国家的消费者对全球化的理解也不同。  相似文献   

9.
建筑业内部与清洁技术和综合资源管理有关的重要问题包括废旧建筑物拆除和建筑材料再循环.根据材料与建筑工程试验和研究实验室国际联合会最近的工作(技术委员会No.121,《废旧建筑物拆除和水泥与石料重复利用指南》)介绍了欧盟及其它国家中目前的发展.讨论了不同层次的技术研究、经济机会和政治战略,特别注意到有关应用和现实目标.描述了最典型的障碍.关于如何克服这些障碍的讨论侧重于灾后重建.  相似文献   

10.
本文介绍了在马来西亚吉隆坡由国际石油工业环境保护协会(IPIECA)组织的和在哥斯达黎回圣约瑟由拉丁美洲和加勒比海地区石油和天然气公司协会(ARPEL)及联合国环境规划署(UNEP)于2002年组织的两个高级区域研讨会的主要发现,这些研讨会的目的是提高对区域发展和气候变化问题的理解,并且识别有效的近期和长期行动的机会,特别是通过清洁发展机制(CDM),对于清洁发展机制项目,私营部门投资仍然存在经济上、方法上和体制上的障碍,围绕清洁发展机制规则的不确定性,已经从设想的关心发展到更为实际的对能力的关心,即组织机构能否以一种及时和成本有效的方式审查和批准项目应用。  相似文献   

11.
Nature reserves have developed rapidly over the decades in China and play a significant role in the function of ecosystem services. The function of ecosystem services in nature reserves, however, has tended to decline in recent years due to natural hazards and human activities. Based on land use, the variation of ecosystem services value (ESV) during 2000–2010 in national nature reserves in Sichuan was evaluated. We analyzed the comprehensive effects of natural disasters and human activities on the decline of ESVs. Total ESV in the national nature reserves in Sichuan was approximately 2741.35 million US$ in 2000, 2616.81 million US$ in 2005, and 2499.06 million US$ in 2010, representing a decrease of 242.29 million US$, or 8.84%, in the decade. Forestland, grassland, wetland, and water bodies played vital roles in the function of ecosystem services, with an aggregated ESV of 99% of the total. The largest proportion of the total ESV was the protection of biodiversity at 48.6%. ESV of all land use types and single ecosystem services continued to decline during 2000–2010. A mechanism of adaptable risk prevention should be established, and unreasonable human activities should be avoided to protect ecosystems and to improve the functions of ecosystem services.  相似文献   

12.
森林土壤固碳机理研究进展   总被引:2,自引:0,他引:2  
全球碳平衡中,土壤有机碳储量为2000 Pg,植被碳储量500 Pg,大气碳储量785 Pg,土壤中有机碳变化是影响大气温室气体含量的重要因素。中国人工林总量世界第一,可以通过造林树种的选择,增加森林土壤的碳汇功能,它主要通过4种机理来实现,包括稳定性有机-矿物复合体的形成、持久性封存的深层碳的增加、耐分解有机物成份的积累、以及土壤团聚体结构中碳的物理性保护。中国近年来对木材的需求上升,导致大量短轮伐期人工林的种植,采伐、火烧炼山、施肥与整地等营林措施对土壤碳汇功能形成重大影响。因而,通过加强对中国人工林土壤固碳机理的研究,通过人为措施实现具有较强固碳能力的森林类型,从而提高人工森林生态系统的固碳能力,它对中国减排增汇战略具有重要意义,而加强对不同营林措施对碳汇功能影响的研究是中国当前面临的重大课题。  相似文献   

13.
中国水稻土碳循环研究进展   总被引:9,自引:1,他引:9  
许信旺  潘根兴 《生态环境》2005,14(6):961-966
文章首先分析了水稻土在碳循环研究中的地位和重要性,进而对我目水稻土碳循环的研究现状作了较为详尽的阐述,对其主要研究结论进行了深入的剖析。中国大而积的水稻土自1980年以来显示出有机碳库增加现象,说明水稻田对大气CO2可能产生汇效应。水耕熟化过程足有机碳的积累过程,水稻土的碳密度是早作土碳密度的2-3倍。水稻土的同碳能力与土壤的微团聚体的粒径有关。但对于水稻土中有机碳的分布和结合状态与农业管理措施、水稻土质量变化、农业生态环境变化的关系仍不清楚。因而建议就这一问题从土壤物理学、化学和生物学的相互作朋与土壤微团聚体中矿物质、有机质和微生物的相互结合关系的层面上进行多学科研究。同时提出了今后我困水稻土碳循环的重点研究方向和领域,即从整体和系统的角度来研究碳循环和平衡,从不同的时空区域来研究碳循环的过程和强度。  相似文献   

14.
Predation risk has been shown to alter various behaviours in prey. Risk alters activity, habitat use and foraging, and weight decrease might be a consequence of that. In mammals, studies on physiological measures affected by risk of predation, other than weight, are rare. We studied in two separate laboratory experiments foraging, hoarding behaviour and expression of stress measured non-invasively from the faeces in the bank vole (Clethrionomys glareolus), a common boreal rodent. Voles were exposed to predation risk using odours of the least weasels (Mustela nivalis nivalis). Distilled water served as control. In the first experiment, we found that foraging effort, measured as sunflower seeds taken from seed trays filled with sand, was significantly lower in trays scented with weasel odour. Both immediate consumption of seeds and hoarding were affected negatively by the weasel odour. Females hoarded significantly more than males in autumn. In the second experiment, the negative effect of weasel odour on foraging was consistent over a 3-day experiment, but the strongest effect was observed in the first night. Foraging increased over the time of the experiment, which might reflect either energetic compensation during a longer period of risk, predicted in the predation risk allocation hypothesis, or habituation to the odour-simulated risk. Despite decreased foraging under predation risk, stress measured as corticosteroid metabolite concentration in vole faeces was not affected by the weasel odour treatment. In conclusion, we were able to verify predation-risk-mediated changes in the foraging effort of bank voles but no physiological stress response was measured non-invasively, probably due to great individual variation in secretion of stress hormones.  相似文献   

15.
中国公众参与环境管理的研究   总被引:18,自引:0,他引:18  
回顾了中国公众参与环境管理的发展历程,分析了公众参与环境管理存在的问题。针对公众参与环境保护管理的有效性的影响因子,例如主观因素、传统背景、时效因素及执行技巧等进行一系列的探讨,并根据公众参与计划的设计构思、公众参与计划的关键两方面的讨论,提出增加公众参与环境保护管理有效性的一些建议。  相似文献   

16.
17.
Time-weighted average concentrations of selected volatile compounds were measured in chosen residences in a Tri-City area of Poland by means of passive sampling. The results were compared to those obtained by dynamic technique – sorption tubes filled with Tenax TA sorbent. Results obtained by employing the two techniques were similar. Total volatile organic compound (TVOC) parameters were also determined. An attempt was also made to evaluate the influence of outdoor air pollutants on indoor air quality.  相似文献   

18.
The background levels of lead in Jamaica in soils and sediments, estimated at 37 mg kg–1, are relatively high compared with world averages. Several areas have values in excess of this due to mineralisation and pollution. One such is the residential Hope Flats/Kintyre area in which levels of lead up to 2.5% are found in the soils and up to 8 g kg–1 in the water of the nearby Hope River. The blood lead levels of a sample of children were in the range 5.7–57 g dl–1. The high lead levels suggest a potential health risk, particularly for the children. This can be minimised by programmes which include community education, case management and abatement to reduce the lead exposure.  相似文献   

19.
硝基芳香化合物是环境中难以降解的污染物之一。因其用途广泛,大量残留于土壤,水体和大气中,造成的环境污染日趋严重。多种植物对该类污染物具有吸收、富集和代谢降解作用,利用植物对其环境污染进行治理是一种有效的方法。文章在总结国内外有关硝基芳香化合物的植物作用研究基础上,重点阐述了植物对硝基芳香化合物的吸收、转运和代谢过程,分析了吸收、代谢机理以及影响吸收的因素;硝基芳香化合物的理化特性、浓度和植物自身特性及其它外界条件都会影响植物对该类化合物的吸收,植物可以通过体内降解、体外联合代谢、根部释放酶催化的机制实现该类化合物的降解。目前,硝基芳香化合物进入植物细胞膜的机理认知不足,模拟模型缺乏有力数据验证;代谢机制中参与反应的酶、化合物等体系和反应产物环境特性仍不明确,植物修复可行性缺乏有力证据。未来将在模型预测构建、降解机理和修复工程的实际应用方面作进一步探究,以形成系统的认知,为硝基芳香化合物污染土壤和农产品的生态风险评价以及植物修复提供理论依据。  相似文献   

20.
The new institution of comprehensive high school, in Greece today, aims to relate the school with the natural, social, economical and cultural environment. In this frame of process, interrelation and dynamic contact of school with the holistic environment, the subject “Ecology and Environment”; of the 2nd class (16–17 years old), informs, sensitizes and activizes the anxious young generation. The textbook of the subject determines and analyzes the human impact and their consequences to the natural ecosystems. In the total content there are also numerous examples from the natural, man‐made and cultural environment of Greece.  相似文献   

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