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41.
加拿大的城市旅游开发评述 总被引:6,自引:0,他引:6
旅游业是加拿大发展最快的产业之一,加拿大也是国际上开展城市旅游比较成熟的国家,其城市和地方政府都把旅游业看作创造就业机会和增加税收的源泉。加拿大的城市旅游开发包括文化旅游、体育旅游、会议旅游三个主要方面。文章指出加拿大城市在城市吸引旅游者方面采取和其他商业活动类似的竞争手段,如参与市场促销、创建城市形象和建设基础设施等。30多年来城市增加了博物馆、体育运动场、会议中心和大型节事活动等项目吸引旅游者。这些投资重新塑造了城市结构,城市旅游景观也已经有了雏形。本文对此作出了评述。 相似文献
42.
1986―2008年广东沿海海平面变化趋势 总被引:3,自引:0,他引:3
根据1993-2008年TOPEX和Jason-1观测的南海海面高度资料和1986-2008年广东省沿海验潮站潮位资料,分析南海绝对海平面及广东沿海相对海平面变化趋势,结果显示:近16年南海(绝对)海平面平均上升率为4.5 mm/a,近23年广东沿海相对海平面上升率为2~3 mm/a,较南海绝对海平面上升率低1~2 mm/a:月平均海平面及年平均海平面变化均存在极强的同步性,在年平均海平面变化中,验潮站的最高值一致出现于2001年.预估未来30年南海海平面比常年升高9~17 cm.海平面上升将加剧珠江口感潮河段的咸潮灾害. 相似文献
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ABSTRACT Environmental sustainability and the long-term wellbeing of Māori (the indigenous people of New Zealand) are interdependent and degradation of landscapes risks the progressive degradation of Māori wellbeing. The present study developed an analysis framework based on Ki Uta Ki Tai (holistic-mountains to the sea- management philosophy advocated by Ngāi Tahu) for exploring relationships between landcover and Māori values to enable predictions of cultural values through space and time. We used this framework to predict how two Māori values (Overall Health and Cultural Land Use) have been altered as a result of landcover change between 2001–2012 in three Canterbury catchments. The area of native vegetation declined while exotic pasture increased between 2001–2012, and there were corresponding declines in both cultural health scores. These results suggest that the change in landcover has reduced the ability of the landscape to support Māori values. This framework for assessing changes in Māori values with respect to changing environmental conditions may identify opportunities for Māori to better engage in land use management decisions. 相似文献
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The main features of upper atmosphere dynamics as an important part of upper atmosphere climatology are presented. The dynamics
of the mesosphere and lower thermosphere (MLT) are of special interest. The results are based on the long series of investigations
in East Siberia and data from a world-wide network of observatories. We present the regional climatic norms for the prevailing
wind and semi-diurnal tide and the main features of the quasi-periodic structure of the wind field. The non-zonality of MLT
dynamics is demonstrated as well as regional differences in the response of the wind field to stratospheric disturbances,
solar activity variations and geomagnetic storms. 相似文献
47.
Topographic shading curtails the period and complicates the geographic patterns of insolation in mountainous areas. Maps derived from oblique aerial photographs of shadow lines cast by the irregular, mountainous east horizon in Provo, Utah are used as a case study to illustrate an alternative to existing techniques of solar radiation data collection. For study areas of several hundred square kilometers, this method may be superior in resolution and at the same time more error free and economically feasible than other methods. Measurement of solar inputs received at sample stations scattered through the mapped area show that the phenomenon of topographically delayed sunrise has a distinct effect on daily totals of radiation in the manner suggested by the maps. 相似文献
48.
Gerald Spreitzhofer 《Natural Hazards》2000,21(1):35-53
Based on the daily fresh-snowrecordings of a set of 81 stations of the AustrianHydrographic Service, covering a 19-year period,various aspects of extraordinarily long-lasting severesnowfalls are investigated. Starting from an exactdefinition of periods of Heavy Snowfall Events (HSE),some of the discussed items include the annual andseasonal frequencies of intense snowfall episodes, thelocation and migration paths of the storm centers andthe volume of snow dropped by the individual storms.Another part of the study, designed to visualize thebig variability of snow-related parameters over Alpineterrain, determines for all involved sites maximalobserved and theoretical extreme fresh-snowaccumulations for periods of variable length. Heavythree-day snowfall events are analyzed with specialregard of the resulting avalanche threat. 相似文献
49.
Becky Mansfield 《Geoforum》2003,34(3):329-342
This paper addresses the cultural economy of nature and the material culture of economic practice. Attending to ways that cultural notions about the biophysical world play key roles in political economic conflicts, discussion centers on two recent debates involving the cultural economy of seafood production and trade. The first debate is over whether the label “catfish” should include catfish imported from Vietnam into the United States; the second deals with whether fish and shellfish should be eligible to be certified “organic” under new US regulations. Analysis reveals that the key dynamic in these debates is not necessarily how people think about “nature”, but instead is how people make distinctions about the world. Rather than focusing on what is natural or not, key actors make distinctions among both organisms and environments. The ways that different groups define and enclose the biophysical world works to distinguish places as either appropriate or not for certain kinds of production activities. The overall argument is that significance and meaning of the biophysical become implicated in economic geographies by making distinctions about the world that then become important for how economic activity can work. As such, cultural economic approaches should attend to the ways that the biophysical is involved in relations such as competition and international trade, while nature-society approaches should shift focus from Nature to specific aspects of the biophysical world. 相似文献
50.
通过定义一个能客观定量描述大气环流四维时空变化的风向改变指数WI,用以研究大气环流的时空演变规律和季节转换。在对纬向平均的WI做了经验正交函数(EOF)分析后,得到了其前四个模态。第一模态揭示的是全年平均的WI空间分布的基态。第二模态反映的是WI场的偏差中呈现准调和变化的部分,热带、副热带、温寒带季风区在该模态中均有明显体现。第三模态反映的是WI场的偏差中呈现非调和变化的部分,该部分揭示了因南北半球海陆分布的差异和因大气、海洋流体的非线性效应,其所造成的从春到秋与从秋到春的季节变化的不对称性以及平流层的二月突变现象。第四模态反映的是全球各层盛行风反向区域从春到夏的北进和从夏到秋南撤的现象。 相似文献