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This study investigated the establishment dynamics of strangler figs and the constraints on their development in the urban parklands of Brisbane, Queensland, Australia. Of 3580 trees and palms in the study parks, approximately 5% support at least one Ficus species. Six Ficus species occur epiphytically in older parkland. Four are Brisbane natives: F. macrophylla, F. obliqua, F. platypoda and F. virens; and two are from elsewhere in Australia: F. benjamina and F. rubiginosa. A lack of pollinator wasps in the Brisbane area prevents exotic and other native Ficus spp. from reproducing. Though they form predominantly open communities, the percentage of phorophytes (support trees) in the study parks is similar to that associated with natural, closed communities. Ficus spp. become established in structural features that accumulate humic soil, such as the forks of trunks and branches on trees, and behind marcescent leaf bases on palms. Plants with few humus pockets support few Ficus species. Environmental factors such as atmospheric quality, canopy shade, bark texture and whether or not a park is irrigated, seem not to be consequential to Ficus establishment. Significantly greater numbers of Ficus occur on deciduous trees, perhaps because avian seed dispersers favour them as perches over evergreen trees. Ficus also occur significantly more frequently on the western sides of palms with marcescent leaf bases. These western flanks offer shelter from the prevailing sea breezes: fewer Ficus are therefore likely to be torn from these sides in strong winds.  相似文献   

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Urban Political Ecology, Justice and the Politics of Scale   总被引:7,自引:0,他引:7  
This and the subsequent papers in this special issue set out the contours of Marxian urban political ecology and call for greater research attention to a neglected field of critical research that, given its political importance, requires urgent attention. Notwithstanding the important contributions of other critical perspectives on urban ecology, Marxist urban political ecology provides an integrated and relational approach that helps untangle the interconnected economic, political, social and ecological processes that together go to form highly uneven and deeply unjust urban landscapes. Because the power-laden socioecological relations that shape the formation of urban environments constantly shift between groups of actors and scales, historical-geographical insights into these ever-changing urban configurations are necessary for the sake of considering the future of radical political-ecological urban strategies. The social production of urban environments is gaining recognition within radical and historical-materialist geography. The political programme, then, of urban political ecology is to enhance the democratic content of socioenvironmental construction by identifying the strategies through which a more equitable distribution of social power and a more inclusive mode of environmental production can be achieved.  相似文献   

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美国城市史学中的人文生态学理论   总被引:2,自引:1,他引:2  
城市史学作为历史学的一个分支学科是在20世纪60年代出现的,它是以埃里克.E.兰帕德的《美国历史学家和城市化研究》一的发表作为新城市史学与旧的方志式的城市史相区别的标志。他在章中明确提出了城市化研究应该作为城市史学家主要致力.的任务,应该把城市社会诸多关联的方面作为一个生态复合体来研究。以后,关于城市化的理论在这一学科范围内不断深化和发展,直至今天,人们约定俗成,承认60年代是城市史学诞生的年代。  相似文献   

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Biological invasions by deliberately introduced organisms seriously compromise the integrity of ecosystems, but their early stages have seldom been documented, especially in urban contexts. Since the 1940s, the small Asian tree Pistacia chinensis has been widely planted in streets and gardens in Armidale, New South Wales, Australia, where it makes a major contribution to the autumn colours that are exploited to promote the city. Numerous wild plants are now becoming established in and near Armidale. This ongoing biological invasion may have been accelerated by the large size of the initial (planted) population, and by the presence of efficient avian seed dispersers. It is now at the stage of the first wild generation reaching reproductive maturity. While it is probably still possible to halt the invasion, various human factors appear to make this an unlikely prospect.  相似文献   

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本共有两则札记。第一则是《S.10号(毛诗传笺)卷背注音之性质》。S.10号《毛诗传笺》卷背有145字之注音,潘重规认为这是六朝《音隐》类作之遗迹,《英藏敦煌献》据之定名为《毛诗郑笺音隐》。本从卷背注音与正面字的关系上考察,认为卷背注音是抄写人据某种《毛诗音》移录,并非是与正字合成有机整体的《毛诗郑笺音隐》,只是它用以注音的方法与六朝的音隐类作相同而已。第二则是《S.541号写卷的正面与背面》,S.541号写卷的一面抄写有《诗经》,另一面抄写有佛典《因缘心释论开决记》。本否定了以前诸家目录以抄写《诗经》一面为背面的说法,认为抄写有《诗经》的一面应是写卷的正面,而抄有佛典一面的内容则为其背面。  相似文献   

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This paper provides an overview of our adaptation of Norton Long's concept of the “ecology of games” into a theoretical framework for analyzing institutional complexity. I discuss the basic concepts of the framework, discuss hypotheses related to fundamental questions in governance and policy, and outline some basic analytical approaches. The conclusion assesses the future prospects of the ecology of games framework, including future research needs for theoretical and empirical development.  相似文献   

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The devastation wrought by landmines on local populations is well known. However, the broader effects of mine presence on postwar recovery, and the progress of a ‘peace process’, remain largely unexamined. Both the academic and the practitioner literature regarding landmines lack a framework within which the mix of economic, political, social, agricultural, and ecological repercussions of mine presence in a context of postwar recovery can be investigated. Here, we consider the utility of political ecology to examine the influence of landmine presence on the socioecological relations important to postwar recovery in Mozambique. Landmines constitute the primary obstacle to the reconstruction and development in Mozambique. Because mine presence influences different aspects of recovery differently, we have selected three cases in the country where mine presence has impacted important components of recovery: agriculture, transportation corridors, and international investment. Peace process and recovery efforts by the international community do not presently address the broader, non-medical influences of landmine presence on recovery, and it is the intention of this article to contribute to an initial examination of these issues.  相似文献   

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The paper concerns the relationships between the physical form of the urban environment and leisure activities. It examines how urban space morphology - i.e. spatial patterns and formal patterns - may have an impact on tourists' attraction and preferences in the contemporary cultural context of urban tourism. Can urban design and the physical form of space in themselves determine anything in urban tourism development?  相似文献   

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Reforms,Globalization, and Urban Growth in China: The Case of Hangzhou   总被引:1,自引:0,他引:1  
Chinese cities have experienced unprecedented growth and restructuring during the reform period. This study by two geographers examines the rapid growth of urban population in the relatively typical large city of Hangzhou (one of China's historical capitals), and investigates underlying factors by highlighting the significance of reforms and globalization in the growth of Chinese cities. The authors also discuss problems that Hangzhou (currently with ca. 4 million inhabitants) faces in coping with rapid urban growth and restructuring. They argue that "control" and "management" approaches to urban growth have limitations in China's transitional cities, and that the gradual process of reform is incompatible with the nature of urban planning in China. Journal of Economic Literature, Classification Numbers: O18, O20, R23. 4 figures, 44 references.  相似文献   

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