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81.
A coalition framework is proposed to address the contentious issues facing agriculture and the environment in urbanising areas, by bringing stakeholders together in homogeneous focus groups to identify areas of common interests, and then in heterogeneous groups to validate the results of the framework. Such a framework encourages greater understanding, consensus building, the resolution of conflicts, and the establishment of coalition efforts in areas of mutual interest and agreement by allowing stakeholder groups collectively to pursue agenda-building on issues of common interests. Based on the authors' observation of the process over an 18-month period, it is encouraging that the coalition framework is an appropriate strategy for building consensus among diverse audiences.  相似文献   
82.
This study is part of a three-year project on biogenic volatile organic compound (VOC) emissions from trees of the temperate warm Atlantic rainforest found in the metropolitan area of Sao Paulo City (MASP). No study of VOC emission rates from plant species has been carried out in the temperate warm Atlantic rainforest of Brazil prior to this work. Eleven species were selected (Alchornea sidifolia, Cupania oblongifolia, Cecropia pachystachia, Syagrus romanzoffiana, Casearia sylvestris, Machaerium villosum, Trema micrantha, Croton floribundus, Myrcia rostrata, Solanum erianthum and Ficus insipida) and some of them were studied in urban, sub-urban and forest areas inside the MASP in order to evaluate biogenic VOC composition at sites characterized by different emission sources. Biogenic VOC emissions were determined by placing branches of plants in a dynamic enclosure system, an all-Teflon cuvette, and by sampling the compounds in the air leaving the cuvette. Pre-concentration using adsorbents to retain the VOC, followed by GC-MS after thermal desorption of the sample, was employed to determine the amount of biogenic hydrocarbons. The collection of carbonyl compounds on a 2,4-dinitrophenylhydrazine coated silica followed by HPLC-UV was used to analyze low molecular weight carbonyl compounds. Emission rates of isoprene, alpha-pinene, camphene and limonene ranged from 0.01 to 2.16 microg C h(-1) g(-1) and emission rates of aldehydes (C(2)-C(6)), acrolein, methacrolein and 2-butanone ranged from 1.5 x 10(-2) to 2.3 micro g C h(-1) g (-1). Ambient and leaf temperatures, relative humidity, light intensity, O(3) and NO(x) levels in the local atmosphere were monitored during experiments. It was possible to identify different biogenic VOCs emitted from typical plants of temperate warm Atlantic rainforest. The emission rates were reported as a function of the type of site investigated and were only provided for compounds for which quantification was feasible. Other biogenic compounds were only identified.  相似文献   
83.
This paper looks at the increasingly complex problems which face physical planners in the urban environment and considers the type of training required in the future for those who have to advise the government of the day on physical planning matters.Using the examples of planning problems which have been experienced in Hong Kong and Saudi Arabia, an analysis shows that they fall into three main categories: (a) physical problems (b) social problems, and (c) visual problems.It is considered that the conventional professionals do not possess the necessary basic training skills to deal with these problems as a whole, nor to discover the hidden opportunities. This is particularily relevant in the context of the growing green debates which are becoming of increasing importance worldwide.As populations grow, the demand from pressure groups for scarce land resources will become more and more intensive. Singapore may face these problems because the government whishes to increase the population from 21/2 to four million.In conclusion it is considered that we shall need a new type of environmental planner in the future. This environmentalist should have a basic training in the earth sciences, the social sciences and the visual arts.  相似文献   
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