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81.
ABSTRACT

We greatly enjoyed reading the paper by Liu et al., which is both timely and rich in insight, as it discusses the challenges in operationalizing the water–energy–food security (WEF) nexus. The nexus approach is gaining increasing attention, both in research and in policy documents, as reflected in the number and content of published documents in the past years and highlighted by the authors.  相似文献   
82.
The first significant government sponsored community‐based forest management project in Australia was initiated in Central Victoria in 2002. This paper analyses the initial stage of the Wombat Community Forest Management Pilot Project. The paper develops a functional concept of ‘effective community’ for structuring community engagement in these kinds of natural resource management projects. The effective community has characteristics in common with a community of interest, adopts a bioregional perspective, embodies the values of environmental stewardship and interacts in a fully informed way as a ‘discursive community’ (Meppam 2000 Meppam, T. 2000. ‘The discursive community: evolving institutional structures for planning sustainability’, Ecological Economics, 34: 4761.  [Google Scholar]). The paper offers general advice for organising effective community engagement in such projects and 12 recommendations for governments developing similar initiatives elsewhere.  相似文献   
83.
第四纪科学发展展望   总被引:12,自引:0,他引:12       下载免费PDF全文
刘东生 《第四纪研究》2003,23(2):165-176
第四纪科学是地球科学的一个分支.20世纪中国第四纪研究的发展历史,可以分为两个阶段:1909~1949年,强调理论研究与实际应用的结合,适当地采用"全盘西化"的办法,将中国与世界先进的差距,由100年缩短为50年,跨越了一大步;1950~2000年,在完成国家需求的鼓励下,适当地越过经典研究范畴,参与环境问题和全球变化的研究,使得中国第四纪科学追赶了50年的差距.在21世纪开始之时,中国与国际第四纪研究的步伐有前有后,但基本上是站在同一起跑线上.对21世纪的第四纪研究,作者提出了以"研究过去只是为了未来"和"地学的文艺复兴在呼唤未来"为题的两个思路,从1)以人为本--务实社会需求;2)地球和人类共同的历史--人与自然和谐;3)我们需要自己提出理论--一种科学文化;4)群众需要第四纪--极大地提高人民的素质等4个方面展望了中国第四纪研究的新形势.  相似文献   
84.
Rapid economic development in the aftermath of the Chinese post-1978 reforms has resulted in a shrinking of grain grown area in the southern and eastern regions of the country which in turn is believed to have put the marginal northern regions under increased pressure. This paper examines key indicators of agricultural performance as well as cultivated land area development of the pre- and post-1978 reform periods focusing on the agro-pastoral Tongliao City Prefecture, eastern Inner Mongolia. The results are related to the village level development through a case study as well as to the provincial level. Average annual grain per capita production increased from about 400 kg in the late 1970s to more then 1000 kg in the late 1990s. This was achieved through a combination of intensification and reclamation of cropland, with the latter restricted to pastoral classified counties. Production variability, in particular for the low producing counties, has also increased possibly as an effect of the substitution of traditional mixed pattern of crops with HYV monocultures. Average living standards have improved but have been accompanied by widening income gaps. Poor farmers’ livelihoods continue to be insecure, particularly during dry years. Concern is raised regarding the sustainability of the rapid agricultural development; an increased use of costly fertilisers constrains poorer farmer’s economy and may lead to deteriorating water quality while increasing irrigation depletes water resources.  相似文献   
85.
Abstract:  The Untouched World Sustainable Cities Youth pilot project was held in Auckland in July 2005. This article outlines the activities that school students were involved in during the week and reflects on the nature of the learning experience. Whilst not specifically targeted at geography students or teachers, the project does support the outcomes of senior high school geography programmes.  相似文献   
86.
We present the hydrometeorology of eastern Asia during April 1995 simulated by the Regional Climate System Model. The amount and location of simulated monthly precipitation agrees well with observations. Soil water content variation was closely correlated with precipitation. Land-surface evaporation and the surface energy budget were strongly controlled by soil moisture content. A sensitivity test with reduced initial soil moisture content suggested that near-surface soil moisture spins up quickly after heavy precipitation events. However, variations in the initial soil moisture field may alter details of the simulated precipitation which can introduce further complexity in climate simulations.  相似文献   
87.
绿洲可持续性评价——以张掖绿洲为例   总被引:6,自引:1,他引:5  
随着绿洲经验的发展,人口的剧增,使得人们对自然资源的需求持续扩大,再加上掠夺式经营和不合理开发,导致了绿洲生态破坏,环境污染等一系列问题,对绿洲的可持续性构成了威胁。本文以张掖绿洲为例,从资源承载力和“三生”指标分析其可持续性,从而提出走向可持续发展的对策建议。  相似文献   
88.
TransportandplanningisuesoftheParisRegion:aquestionofsustainabilityWONGTai-CheDivisionofGeographyNanyangTechnologicalUnivers...  相似文献   
89.
持续农业及其中国态势   总被引:31,自引:0,他引:31  
蔡运龙 Smit  B 《地理学报》1995,50(2):97-106
农业是发生在生物-自然、社会-政治、经济-技术这三重环境内各种过程的综合体,因此农业的持续性也可归纳为生态、经济、社会三重定义。持续农业在不同的空间尺度上具有不同的意义,在地方和区域尺度上就是生态农业,在国家和全球尺度上,则更注意食物及其分配问题,据此,本文分析了中国持续农业面临的挑战与具有的潜力。  相似文献   
90.
This paper examines the differing modes of insertion of the Australian and New Zealand apple industries into world apple markets, part of the evolving global fresh fruit complex. It is argued that the mix and behaviours of key actors in the global apple industry are realigning market links and production systems. Industry actors in Australia and New Zealand are confronting issues of quality and sustainability as a result of pressures from consumers, regulatory measures in traditional and emerging markets, and new technologies of production and distribution. Governments are laying the foundations of national, regional and industry sustainability policies. An examination of the detailed structure and adjustments of the apple industry in Hawkes Bay and Tasmania reveals considerable differences in local responses, institutions and degree of restructuring of markets. The preferences and quality control requirements of export markets are increasingly important, to the extent that cultural dimensions appear to be altering the commodification process.  相似文献   
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