共查询到20条相似文献，搜索用时 15 毫秒
1.
2.
Bird-watching is an increasingly popular leisure activity. Previous research has taken for granted the identity of people who watch birds, often categorised by their level of skilled practice as ‘dude’, ‘birder’ or ‘twitcher’. Feminist geographers encourage us to explore identity work as an outcome of the reciprocal relationships between practices and place. Our feminist approach illustrates that the practices of bird-watching are always much more than categorising birds as species. This paper illustrates how the practices of bird-watching are integral to the making and remaking of sense of place as ‘home’ and ‘away’, to sustain identities beyond accepted categories of ‘dude’, ‘birder’ and ‘twitcher’. The creation and application of different types of ‘bird-lists’ helps to explain the ways in which practices of bird-watching facilitate making sense of place as simultaneously ‘home’, ‘away’ and habitat, as well as the identity work of home-maker, citizen-scientist and tourist. Our insights into these leisure practices of bird-watching are drawn from analysis of data gathered from 21 people who actively bird-watch and reside on the South Coast, New South Wales, Australia by combining research methods of talking, walking, drawing and photography. 相似文献
3.
《热带地理》2001,21(3):282-289
编者的话 <热带地理>自1999年第4期起开辟了"争鸣园地”栏目,并以粤东"‘冰臼'与‘壶穴'之争”为题开展热烈讨论.至今两年来,在广大读者竭诚支持下,本栏目在国内外地学界已产生了广泛影响,争鸣至今热度未减.现因内容安排等原因,对本专题的讨论只能暂告一段落.
为继续贯彻"学术争鸣”方针,加强地学各相关专业之间的交流,促进学科发展,本刊编辑部于7月20日在广州地理研究所组织举行了关于"‘冰臼'与‘壶穴'之争”的专题讨论会.与会者有来自广州地区有关的专家、学者和专业科技人员共20多人,南方日报并派记者到会采访.会议自始至终充满热烈气氛,专家们以严肃认真、实事求是的科学态度进行了全面深入的探讨.在此基础上,为满足广大读者的迫切要求,现将所收到的专家书面发言稿,包括未能到会的专家为本栏目撰写的稿件一并刊出.为客观地反映会议情况,同时解决稿件多而版面不足的矛盾,特别是为持不同见解者提供发表意见的一席之地,稿件一律以简短的笔谈形式编发.又根据"文责自负”原则,稿件处理力求在内容、观点、风格等方面保留其"原汁原味”.
虽然,对本专题的讨论现已暂告一段落,但这绝不意味着争鸣已"划上了圆满句号”.广大读者通过对两年来争鸣过程的深入了解和分析,当可作出各自的判断.今后,如有新的意见和建议,还可直接向本刊提出,我们仍会以各种适当方式予以及时反映.
<争鸣园地>将是一个常设栏目,希望广大读者继续给予有力支持,我们也将一如既往竭诚为读者提供周到服务.
曾昭璇(华南师范大学地理系教授):
近来争论的冰臼和壶穴问题看来应该结束了.想利用"冰臼”这个珍奇地貌现象来办旅游点的同志是不会放弃他的观点的,学术界对"冰臼”论的错误,也不会同意的.
本人认为所谓冰臼,实为壶穴,即为近代流水作用所成.理由可举几个例说明.
1. 40年前,本人研究红土荒坡时见到,大雨后红土荒坡被流水冲蚀一条小沟.小沟内的水流呈急速旋涡状流动.因此,很快小沟两坡就被蚀出一个个小型的"壶穴”地形来了.可见壶穴是近代流水所成的.
2. 1956年考察"韩江上游地形”时,在急流冲刷的花岗岩河床上,即可见到壶穴成群发育,并且有些呈"管状”壶穴,成行成排时,就把河床掘出一条深深刻入岩体中的小沟,成为河谷加深的部分.这表明洪水期流水涡流侵蚀作用的强烈.
3. 北方我去黄河壶口瀑布考察时,也在瀑布两侧的石质河床面上看见散布的壶穴.在陕西岸段看到一个标准的壶穴,它的上覆地层为红色土及黄土层,不见冰碛物.这也说明即使在北方,壶穴地貌也是流水侵蚀的结果.
4. 有一年,黄河修刘家峡水库,我有幸随水利部工程车去参观.亦见峡底出露后呈现巨型壶穴群的地貌,壶穴直径大至5～8 m,使河底每呈小型瀑布式的涡流,正如今天山区的瀑布潭一般,也说明黄河峡谷水下峡谷底部壶穴地貌,也是现代流水侵蚀的结果.
5. 在新出版<热带地理>2001年第21卷第2期封三照片②"揭西石肚溪冰碛砾石表面形成的‘钉头鼠尾'冰川擦痕”是错定的.这是泥石流中的擦痕,泥石流流动时,石块互相撞击产生的.因为本人在北欧平原(波兰)及北美冰碛区(加拿大地区)所见的"钉头鼠尾”砾石上刻痕,有它的特征,不是这样的.
①冰川刻痕石块是成群分布,不是个别出现,要小心去找才能找到.我曾在庐山大校场冰川末端找到过,所以不相信李四光教授说这是冰川堆积物.那里大小石块是一起堆着的.
②冰刻条痕是有个磨面的,磨面很光滑.磨面上还有一群不同走向的磨痕,也是成群的作同一走向.
③冰刻痕是在光滑磨面上,以几组深度不同、大小不等、方向不一的刻痕存在的.
④"钉头鼠尾”刻痕与石块节理、矿物成分无关.如庐山的石壁上冰川水平擦痕,是花岗岩体近水平排列的长石成带状时,长期风化后呈槽状水平刻痕似的风化槽形凹入.故本人不相信这几条凹槽是冰川U形谷两侧的冰磨痕.
⑤刻痕冰碛层产状也是每呈层状,磨圆也不错,且下部多在冰川磨光岩面上堆积着,即冰碛物也是呈层状产出,不像"蛇形丘”(冰川下河流)的大小不同石块与沙泥堆积在一起.
以上的成果都是国际地理学会、地质学会的野外共同考察后的共识.本人参加国内学会组织的考察所见所谓"冰碛物”没有这些情况,而是与泥石流的情况一致的. 相似文献
4.
《热带地理》自 1999年第 4期起开辟了“争鸣园地”栏目 ,并以粤东“‘冰臼’与‘壶穴’之争”为题开展热烈讨论。至今两年来 ,在广大读者竭诚支持下 ,本栏目在国内外地学界已产生了广泛影响 ,争鸣至今热度未减。现因内容安排等原因 ,对本专题的讨论只能暂告一段落。为继续贯彻“学术争鸣”方针 ,加强地学各相关专业之间的交流 ,促进学科发展 ,本刊编辑部于 7月 2 0日在广州地理研究所组织举行了关于“‘冰臼’与‘壶穴’之争”的专题讨论会。与会者有来自广州地区有关的专家、学者和专业科技人员共 2 0多人 ,南方日报并派记者到会采访。会议自始至终充满热烈气氛 ,专家们以严肃认真、实事求是的科学态度进行了全面深入的探讨。在此基础上 ,为满足广大读者的迫切要求 ,现将所收到的专家书面发言稿 ,包括未能到会的专家为本栏目撰写的稿件一并刊出。为客观地反映会议情况 ,同时解决稿件多而版面不足的矛盾 ,特别是为持不同见解者提供发表意见的一席之地 ,稿件一律以简短的笔谈形式编发。又根据“文责自负”原则 ,稿件处理力求在内容、观点、风格等方面保留其“原汁原味”。虽然 ,对本专题的讨论现已暂告一段落 ,但这绝不意味着争鸣已“划上了圆满句号”。广大读者通过对两年来争鸣过程的深入了解和分析 , 相似文献
5.
‘98洪涝灾害的深层次原因系统分析 总被引：2，自引：1，他引：1
彭珂珊 《云南地理环境研究》1998,10(2):14-24
１９９８年６月～１９９８年９月长江流域发生特大洪灾,以高水迎峰,上压下顶,峰急水猛,时长量大为特征,百万军民齐心协力,坚持到底,夺取了抗洪救灾斗争的决定性胜利。分析洪灾形成的主要原因,除气候反常、降雨集中等自然因素外,也存在水土流失,植被减少,围湖造田,河道淤积,水利工程失修、老化,法制观念淡薄,投入问题尖锐,承灾功能脆弱,人口急剧增长,协调失误等深层次的问题。对此作系统分析,以期能供决策部门在以后抗洪救灾中参考,对职能部门起到咨询作用 相似文献
6.
《新闻早报》【天宫一号与神舟九号今日将实施手控交会对接】组合体在轨飞行6天后,天宫一号与神舟九号2012年6月24日11时9分将短暂分离,并在12时58分实施第二次交会对接,12时55分成功完成。此次对 相似文献
7.
《The Professional geographer》2013,65(2):124-129
Abstract This study examines the role of surface geomorphic features in tree establishment at the alpine treeline in Glacier National Park, Montana, through the presentation of a multiscale, conceptual model of biogeomorphic relationships at alpine treeline. Empirical observations gathered through a multiscale field methodology over three summers serve as a base for the model. The model highlights the importance of surface geomorphic features, specifically boulders and terrace risers, in creating favorable local site conditions, largely by protecting seedlings from wind. The sheltering effect of surface features enables initial seedling establishment, and in some cases survival, above current treeline locations, thereby initiating a positive feedback effect that encourages subsequent tree establishment. Geomorphic features are therefore important in linking scales of pattern and process at the alpine treeline ecotone. 相似文献
8.
Gretel Boswijk 《New Zealand geographer》2010,66(2):124-137
This paper explores how the recent history of kauri is remembered and commemorated on the Kauri Coast, western Northland, focusing on three specific heritage sites: The Kauri Museum at Matakohe, Trounson Kauri Park, and Waipoua Forest Sanctuary. Each site was established to preserve elements of the past before they were lost or irrevocably altered. The museum commemorates the pioneers and the kauri timber and gum industries, while Trounson Kauri Park and Waipoua Forest were intended to represent primeval forest and stand as monuments to people who advocated their protection. 相似文献
9.
10.
Our sedimentological study of Lobos Lake sediments has shown that, below modern deposits, there is a clastic and biological record of three different paleoenvironments: two aquatic (freshwater and mixohaline respectively) and one subaereal. This record documents the climatic and geomorphologic changes that affected the basin during its evolution up to its present water level, from the upper Pleistocene to the Holocene.This is the seventh in a series of papers published in this issue on Paleolimnology in Southern South America. Dr. C. A. Fernández served as guest editor for these papers. 相似文献
11.
Kiribati: an environmental ‘perfect storm’ 总被引：1，自引：0，他引：1
Recent environmental discourses and headlines on small island developing states (SIDS) have heralded the grave and impending threats of global warming and associated sea-level rise. These are undoubtedly significant challenges for SIDS, including atoll nations such as Kiribati. Nevertheless, securing small island state futures also requires a renewed commitment to addressing the obvious and immediate threats of urbanisation, pollution and sanitation. Looking at pressures of development on freshwater, this article argues that the future survival of small island states and their societies also greatly depends on managing the impacts of development. Approaches which can concurrently strengthen the resilience of communities and their ecosystems will result in mutual benefits for both sustainable development and climate change adaptation. 相似文献
12.
Tim Frewer 《The Australian geographer》2013,44(1):97-114
Two fundamental pillars of what it is to be a contemporary NGO and ‘do’ development work are being a part of and promoting civil society, and extending ‘good governance’. This article will provide insights into how supposedly universally applicable concepts and models for NGOs to ‘improve’ post-conflict ‘developing countries’ are incorporated into different social and cultural landscapes. Ethnographic fieldwork highlights some of the particularities of governance, as well as everyday challenges of doing NGO work in a remote province of north-eastern Cambodia. In the context of an authoritarian government, where kinship relations cross-cut all aspects of society, NGOs can be understood as embedded in neo-patrimonial networks rather than as a separate and autonomous realm of society as classic liberal theory understands ‘civil society’. Fear also plays a significant role in configuring peoples’ attitude towards authority and is rarely acknowledged in the project of ‘good governance’ which simplistically tends to see post-colonial governments situated on a linear trajectory which will eventually, with significant NGO interventions, reach advanced liberal democracy status. 相似文献
13.
14.
广东‘94特大洪水与防洪涝对策 总被引：2，自引：2，他引：2
本文介绍了广东自然地理概况和主要河流的洪水特点，分析了广东‘９４物大暴雨洪水的特性和防洪涝中出现的主要问题，提出了进一步采取有效的综合防治洪涝灾害的对策。 相似文献
15.
Hawai‘i's agricultural landscape was previously dominated by large monocrop plantations of sugar cane and pineapple, but following a sweeping series of plantation closures beginning at the end of the twentieth century, that era has concluded. The last spatial assessment of Hawai‘i's agricultural footprint was completed in 1980, during the active plantation period. Here we present the results of a 2015 statewide assessment of the commercial crop footprint for Hawai‘i, based on World-View 2 satellite imagery and supporting datasets. We analyzed changes relative to the 1980 baseline on both a statewide and regional basis, to better understand how Hawai‘i's agricultural system has evolved in the post-plantation era. Sugar cane and pineapple saw dramatic reductions during this period, collectively losing more acres (257,000) than were planted for all crops combined (152,000) in 2015. Idle plantation lands and past plantation-era investments in irrigation and other infrastructure have created opportunities for other types of agriculture, despite rising land values, new and existing tropical diseases, and other challenges. Seed crops, primarily for genetically modified corn trials, were the second largest crop in 2015 (24,000 acres) despite having no mapped footprint in 1980. Commercial forestry, also absent in 1980, covered 23,000 acres in 2015. Macadamia nut, coffee, and diversified agriculture also all saw significant gains in their footprints, with coffee plantings increasing >250% during this period. Despite these gains, the Hawaiian Islands continue to have an extremely low degree of self-reliance for food production. The Oahu plain, adjacent to the major population center of Honolulu, has the most potential for considerably increasing the production of local produce, but without changes in consumption patterns and significant efforts to protect agricultural land from development, any increases in local food production will continue to be incremental. The post-plantation agricultural landscape in Hawaii is smaller, more diversified, and more nimble than it was in 1980, reflecting inter-island geographic differences in land use, history, and ownership. Mapping and assessing spatial changes in agricultural activity over time can provide valuable insights for decision-makers and communities as they continue to define what agriculture should look like in the post-plantation era. Our results suggest that Hawai‘i's agricultural landscape and overall production capability will continue to contract without substantial changes in policy and practice. 相似文献
16.
James D. Wickham† Kurt H. Riitters Robert V. O'Neill K. Bruce Jones Timothy G. Wade 《International journal of geographical information science》2013,27(7):891-899
Abstract Raster land cover data has been used to construct adjacency matrices by scanning the pixel edges and calculating proportions according to the land cover types joined. Like joins (e.g., forest to forest) are most common because pixel size is typically much smaller than the average patch size. The dominance of like joins (the matrix diagonal) of the adjacency matrix has led to one interpretation of the matrix as landscape contagion (the tendency of land cover to cluster into a few, large patches). Construction of the adjacency matrix in a vector environment results in a different measurement. In a vector environment, land cover patches are not sub–divided into pixels. Therefore, the main diagonal of the adjacency matrix is zero. Construction of an adjacency matrix in a vector environment estimates the evenness of distribution of edge types, not contagion. The same edge type evenness metric is estimated in a raster environment by ignoring the matrix diagonal and re-scaling the off-diagonal elements so that they sum to one (1). 相似文献
17.
‘98嫩江,松花江洪水与流域综合管理 总被引：16，自引：4，他引：12
１９９８年夏季,嫩江,松花江流域发生历史罕见的洪水,此次洪水主要特征是水位高,水量大、持续时间长,灾情严重,由于嫩江支流相继发生洪水,致使嫩江干流再现三次较大的洪峰。农作物受灾面积４５６×１０＾４ｈｍ＾２,洪灾的主要原因是雨量大,汛期长,土地利用不合理,区域生态环境退化,缺乏控制性水利工程,亟需开展流域综合管理工作,加强水利工程建设,尤其是控制性水利工程建设,发展生态安全型农业。 相似文献
18.
The 167 sample lake-water pH-diatom calibration data-set created as part of the Palaeolimnology Programme within the Surface Water Acidification Project (SWAP) is re-analysed numerically using nine different numerical methods, six based on simple two-way weighted-averaging (WA), and the other three involving Gaussian logit regression (GLR) and maximum-likelihood (ML) calibration, the modern analogue technique, or weighted-averaging partial least-squares regression and calibration. Root mean squared error of prediction and maximum bias were estimated for all nine methods based on 10,000 internal and 10,000 external cross-validations involving a training-set, an optimisation-set, and a test-set. The results show that WA with a monotonic deshrinking spline equals or slightly outperforms WA with linear inverse deshrinking, especially in external cross-validation. Methods that employ tolerance downweighting generally have an inferior performance except when combined with monotonic deshrinking. It appears that simple two-way WA extensively used in SWAP cannot be significantly bettered. Thanks to increased computing power, better software, and more rigorous cross-validations, GLR shows good performance, especially in external cross-validation. 相似文献
19.
K. A. McL. ADLAM A. R. CLAYTON B. KELK 《International journal of geographical information science》2013,27(2):161-170
Abstract A survey of users of geosciences data in Great Britain, carried out as part of the Databank Pilot Study jointly supported by the Department of the Environment and the British Geological Survey, indicated a priority requirement for a central geosciences data index. The consultations suggested that the system should contain information about the sources, accessibility and nature of data held in both centralized and widely-distributed collections. To illustrate to users how such a system would appear in its final implementation, and in order to refine the system's specification, the British Geological Survey developed, on an Intergraph Interpro 32 Workstation, a working demonstration of a ‘user-friendly’, interactive graphical index, capable of satisfying the requirements of a wide range of users of geosciences data. This paper describes the development of the ‘demonstrator’, its structure, content and implementation, and the benefits of adopting such an approach. 相似文献
20.