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171.
Jeffrey Barber 《Environment, Development and Sustainability》2003,5(1-2):63-93
At the World Summit on Sustainable Development (WSSD), world leaders agreed that eliminating unsustainable production and consumption is one of the three overriding objectives of sustainable development. Achieving that objective should have been a major priority for the WSSD Plan of Implementation. Increases in consumption and production over the past decade were largely responsible for the worsening environmental and social trends. Unfortunately, the negotiators of the Plan paid insufficient attention to the lessons from 10 years of discussions about the concepts, the available policies and tools and their effectiveness, the impacts of those policies on developing countries, and the political commitment of countries in an era of globalization. Despite a promising proposal for a new ten-year work programme aimed at bridging the gap implementing the Agenda 21 commitments from Rio, Summit negotiators produced barely more than a muted echo of recommendations from the past which have yet to be taken seriously enough by the world's leaders in a comprehensive intergovernmental strategy. In the ten-year review of progress to achieve sustainable production and consumption (SPAC), governments quickly skipped past the critical work of examining why things are getting worse, avoiding the task of identifying the obstacles (which in some cases were themselves) and in turn avoiding the commitment to time-bound measurable targets. If nothing else, the WSSD demonstrated that a global strategy to achieve SPAC will come not from a UN consensus of world leaders but from a strategic alliance of responsible governments, civil society and others with a vision beyond the next election cycle. 相似文献
172.
Walter M. Farina 《Behavioral ecology and sociobiology》1996,38(1):59-64
Dancing and trophallactic behaviour of forager honey bees, Apis mellifera ligustica >Spinola, that returned from an automatic feeder with a regulated flow rate of 50% weight-to-weight sucrose solution (range:
0.76–7.65 μl/min) were studied in an observation hive. Behavioural parameters of dancing, such as probability, duration and
dance tempo, increased with the nectar flow rate, though with very different response curves among bees. For trophallaxis
(i.e. mouth-to-mouth exchange of food), the frequency of giving-contacts and the transfer rate of the nectar increased with
the nectar flow rate. After unloading, foragers often approached other nest mates and begged for food before returning to
the food source. This behaviour was less frequent at higher nectar flow rates. These results show that the profitability of
a food source in terms of nectar flow rate had a quantitative representation in the hive through quantitative changes in trophallactic
and dancing behaviour. The role of trophallaxis as a communication channel during recruitment is discussed.
Received: 14 January 1995/Accepted after revision: 14 August 1995 相似文献
173.
F.E. Trainer 《Resources Policy》1982,8(1):41-52
There are a number of factors which are likely to limit the proportion of potentially recoverable resources that will actually be recovered. The most important of these concern the way minerals are distributed within the crust and trends in energy costs associated with mineral production. This article offers a pessimistic view of the prospects for mineral supplies early in the 21st century. The resource situation is even less hopeful when the possibility of extending the material living standards of the developed countries to everyone likely to be living on earth late next century is considered. 相似文献
174.
Walker P 《Disasters》2005,29(4):323-336
This paper reflects on the genesis of the Code of Conduct for the International Red Cross and Red Crescent Movement and Non-Governmental Organizations (NGOs) in Disaster Relief, on the tenth anniversary of its adoption. The origins, usage and future of the code are examined with respect to three debates, current at the time of its inception, namely: the debate about the core content of humanitarianism; the debate about coherence and the consensual nature of the humanitarian community; and the debate about the need for, and the ability to demonstrate, accountability. The paper concludes that although the Code of Conduct was very much a product of its time, its content remains relevant today. However, its future application hinges on the capacity of those who purport to follow it to realise true accountability, and on proving that the code, written essentially for natural disasters, is relevant to contemporary complex emergencies. 相似文献
175.
可持续发展下的生态经济学理论透视 总被引:10,自引:1,他引:9
生态经济学是一门正在蓬勃发展的新兴交叉学科,可持续发展是生态经济学研究的中心问题。人类对可持续发展问题的极大关注推动了生态经济学的发展。本文从宏观角度分析了可持续发展问题的凸显和生态经济学的兴起,着重指出生态经济学是关于可持续发展的科学的认识;阐述了可持续发展条件与状态的生态经济学理论内涵;论述了生态经济系统的本质特征及其可持续发展评估的核心内容;概括了可持续发展评估与绿色国民经济核算的框架及其目标和衡量方法。 相似文献
176.
从开采方法、土地复垦与综合治理、经济和政策等方面采取措施,可以最大限度地减小采矿对土地资源的破坏,治理好矿区土地资源,保护好耕地,实现粮食产需总量的大体平衡。“保护粮食安全”关键是抓好耕地保护,根据可持续发展原则,综合考虑矿业经济发展与矿区生态环境保护的关系,走矿业“绿色开采”的道路,研究有利于矿区耕地保护的采矿新技术,使资源开发与耕地保护协调发展,同时还应对煤矸石和粉煤灰进行充分利用、防治水体受到污染、采用先进的土地复垦技术对土地资源的浪费和破坏进行治理,把土地复垦中的经济效益、社会效益和生态效益统一起来,为粮食生产奠定基础。 相似文献
177.
Kirkpatrick AJ Gerhardt A Dick JT Laming P Berges JA 《Environmental science and pollution research international》2006,13(4):242-250
Background Biological monitors are increasingly important in 'Biological Early Warning Systems' (BEWS) for monitoring water quality.
This study examines the freshwater amphipod Crangonyx pseudogracilis as a potential new indicator species when used in the
Multispecies Freshwater Biomonitor (MFB). The MFB is an online continuous biomonitor which uses impedance conversion to record
behavioural responses of vertebrates and invertebrates.
Methods Four experiments were undertaken to establish: (1) if the electrical field generated by the MFB affected the organisms' behaviour,
(2) if defined behaviours and their response to a gradient of ammonium chloride could be detected by the MFB, (3) if there
was variation in the behaviour of C. pseudogracilis over a diel cycle, and (4) if behaviour changed significantly in response
to a pulse of ammonium chloride.
Results and Discussion Results showed no significant effect of the MFB's current on behaviour of C. pseudogracilis. Four behaviours; swimming, walking,
grooming and inactivity, were observed and identified in the MFB. In the MFB, each behaviour changed significantly in response
to an increasing gradient of ammonium chloride exposure. The MFB also detected increases in nocturnal activity by C. pseudogracilis.
The MFB also detected a significant increase in activity after a pulse of ammonium chloride.
Conclusion The range of behaviours exhibited by Crangonyx pseudogracilis, together with its ease of culture, suggest future potential
of this species as an indicator species for the Multispecies Freshwater Biomonitor.
Recommendations and Perspective . Further testing is required over a range of toxicants and concentration gradients to establish threshold responses and the
full compliment of behaviours that could be useful in online biomonitoring. 相似文献
178.
中美两国经济发展与铜消费量对比研究 总被引:4,自引:0,他引:4
发达国家的发展过程表明,经济增长与铜消费量密切相关。本文由IPAT方程推导了铜消费指标与GDP间的关系式,得出GDP的年增长率(g)的单位GDP铜消费量的年下降率(t)是影响铜消费量变化的两个重要参数。给出了中、美两国铜消费指标与GDP间的关系曲线;中国1960-2004年间单位GDP的铜消费量并未形成明显的上升或下降趋势;美国1941-2004年间单位GDP铜消费量的变化总体上逐年降低,1941年为17.80kg/10^4USD,2003年为2.56kg/10^4USD,单位GDP的铜消费量降低近7倍。对应不同的单位GDP铜消费量年下降率的假设,估计了未来25年内中国经济增长与铜消费指标间的关系以及单位GDP铜消费量降低的倍数。 相似文献
179.
180.
城市绿色空间及对城市热岛效应的影响 总被引:43,自引:0,他引:43
采用遥感技术结合实地测定的研究方法,利用1987年至2001年遥感卫星影像数据,建立了北京市不同年份的城市绿色空间专题图和热岛分布图,分析了13年中北京城市绿色空间及热岛效应的演变特点,评价了城市发展及城市绿化对热岛效应的影响。结果表明:受城市化的影响,14年中北京城市绿色空间变化明显,城市热岛效应也随之发生明显变化;随着城市建设范围的扩大,原有自然植被不断减少,热岛影响范围随之扩大;随着市区内的绿化建设,绿色空间总量增加,热岛效应有缓解的趋势。 相似文献