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1.
华山树木年轮年表的建立   总被引:83,自引:2,他引:83  
邵雪梅  吴祥定 《地理学报》1994,49(2):174-181
本文以秦岭东部的华山为例,论述了建立常规标准化、差值、自回归标准化这三种树木年轮年表的途径,指出了在半湿润地区利用这种途径建立树木年轮气候学年表的必要性,并进一步分析了三种年表对气候要素的响应及其差异。在取样环境较复杂的地点,建立多种年表有利于深入探讨气候要素与树木生长之间的关系,有推广的价值。  相似文献   
2.
树轮年代学的若干进展   总被引:60,自引:10,他引:60       下载免费PDF全文
邵雪梅 《第四纪研究》1997,17(3):265-271
树轮年代学是一门研究树木木质部年生长层,以及利用年生长层来定年的科学。由于树轮不仅是一种定年工具,它本身还可提供树轮生成时的环境要素信息,为一种环境变化的代用资料。在全球变化特别是在过去全球气候变化研究中,树轮年代学受到愈来愈广泛的重视,在近期内取得了长足的、惊人的进展。本文仅在树轮长年表的建立,树轮年代学生物基础研究──模式研究,利用树轮对环境要素变化的研究,以及树轮的图像分析等几个与环境变化研究相关的方面和本学科目前研究热点的若干进展,予以概要的论述。  相似文献   
3.
4.
RADIAL GROWTH OF HUASHAN PINE AND ITS RESPONSE TO CLIMATE   总被引:4,自引:0,他引:4  
Intr0ducti0nltiswell-knownthattl1eannualringSoftreeprovideuniqueinformationfOrdeductionofpastclimaticchange.ProPertiesoftreeringrsuchaswooddensityandringwidthvaryinresPOnsetoclimaticc0nditionsthatlimittreegrowth[7,l4].ByunderstandingtherelationsllipsbetweentreegroWthandclimatevariables,PaStclimaticvariationscanbederivedfromtree-ringdata.InChina,mostdendroclimaticstudieshavebeenconductedonclimaicallyextremesites[l2,l8,l9].TreesgrOwingonsuchsiteshavestrongandstraightfO~relationshipswithclim…  相似文献   
5.
中国树木年轮气候学研究动态与展望   总被引:23,自引:0,他引:23  
介绍了我国的树木年轮气候学研究取得的新进展,包括野外取样、建立年表,“年轮—气候”相关分析、密度分析和模式研究等方面。同时,还论及了今后在我国开展该项研究的前景与潜力。  相似文献   
6.
The Sudetes Mountains (Central Europe) were under a particularly intense long-term air pollution load during the 1970s and 1980s. Intense industrial activity in this area led to large-scale forest dieback and reductions in tree growth rates, potentially limiting the use of tree-ring data from this region in dendroclimatic research. In this paper, ring-width chronologies were constructed for 493 Norway spruce trees (Picea abies L. Karst.) from 17 sampling sites within five major mountain ranges in the Sudetes Mountains of Poland. Growth-climate response data indicate that April?July temperatures are the main factor affecting radial growth of trees in the study area. Our data also indicate the strong influence of slope aspect on temperature signal strength. The lowest correlation values were obtained for sites located on western slopes with effective fog deposition, which are strongly affected by pollution. An appropriate sampling strategy resulted in the creation of a temperature-sensitive proxy record (rAMJJ = 0.70), exceptional for areas under strong pressure from human activity. Based on a regional master chronology, growing season (April?July) temperatures over the past 200 years were then reconstructed. Four warm and four cold periods were distinguished and compared with other reconstructions and long-term instrumental data.  相似文献   
7.
BOOK REVIEWS     
Book Reviewed in this article: Geography and the Third World. International Seminar, 14–18 May 1980, Kuala Lumpur, Malaysia . Ishmail Ahmad and Jamaluddin Md Jahi, eds. The Growth Dilemma: Residents' Views and Local Population Change in the United States . Mark Baldassare. Sport and Place: A Geography of Sport in England, Scotland & Wales . John Bale. The Deindustrialization of America: Plant Closings, Community Abandonment, and the Dismantling of Basic Industry . Barry Bluestone and Bennett Harrison. Selected Essays 1963–1975: Carl O. Sauer . Bob Callahen, ed. Housing and Planning in the Countryside . G. Clark. Conflict, Politics and the Urban Scene . Kevin R. Cox and R. J. Johnston, eds. Thematic Maps: Their Design and Production . David J. Cuff and Mark T. Mattson. Wine: A Geographic Appreciation . Harm Jan de Blij. USSR in Maps . J. C. Dewdney. Political Geography: A Contemporary Perspective . Ramesh D. Dikshit. Rethinking Human Adaptation . Rada Dyson-Hudson and Michael A. Little, eds. Sacred Sands: The Struggle for Community in the indiana Dunes . J. Ronald Engel. Geography of the Biosphere . A. Furley and Walter W. Newey. Disaster and Reconstruction . Robert Geipel. Glasgow: The Making of a City . Andrew Gibb. Design for Arid Regions . Giden S. Golany, ed. Urbanization and Cancer Mortality: The United States Experience, 1950–1975 . Michael R. Greenberg. Geology in the Nineteenth Century: Changing Views of a Changing World . Mott T. Greene. Colonización y Destrucción de Bosques en Panamá . Stanley Heckadon Moreno and Alberto McKay, eds. Urban Geography: A First Approach . David T. Herbert and Colin J. Thomas. The Visual and Spatial Structure of Landscapes . Tadahiko Higuchi. Climate from Tree Rings . M. K. Hughes, P. M. Kelly, J. R. Pilcher, and V. C. LaMarche, Jr., eds. The structure of Nineteenth Century Cities . James H. Johnson and Colin G. Pooley, eds. The American Planner: Biographies and Recollections . Donald A. Krueckeberg, ed. Urban Land Policy For the 1980s, the Message for State and Local Government . George Lefcoe, ed. Regional Planning: Evolution, Crisis and Prospects . Gill C. Lim, ed. Relevance and Ethics In Geography . Bruce Mitchell and Dianne Draper. China: The Geography of Development and Modernization . Clifton W. Pannell and Laurence J. C. MA. The Urban Retailing System . Robert B. Potter. Hants. Nonconventional Energy Resources . Philip R. Pryde. Caribbean Migrants: Environment and Human Survival on St. Kitts and Nevis . Bonham C. Richardson. Population and Resources . Harry Robinson. East Los Angeles: History of A Barrio . Ricardo Romo. Integrated Impact Assessment . Frederick A. Rossini and Alan L. Porter, eds. Environmental Aesthetics: Essays in Interpretation . Barry Sadler and Allen Carlson, eds. Earthwatch . Charles Sheffield. Field Techniques and Research Methods in Geography . Robert H. Stoddard. Haiti: Land of Poverty . Robert J. Tata. Weathering and Erosion: Sources and Methods in Geography . Stephen T. Trudgill. Once Beneath the Forest. Prehistoric Terracing in the Río Bec Region of the Maya Lowlands . B. L. Turner, II. The Historical Geography of Scotland since 1707 . David Turnock.  相似文献   
8.
Timber removal on publicand private land surrounding Redwood National Park exacerbates naturally high rates of erosion that are common to this region and alters hydrologic processes within the park boundaries. These alterations of the natural environment complicate the efforts of the National Park Service to preserve a remnant of the once extensive coastal redwood ecosystem in the park. A watershed model for Redwood Creek calibrated to pre-logging conditions is employed to define and quantify changes in the hydrologic response of the basin during the years when timber harvesting reduced significantly the acreage of redwoods. Analysis of modeled and observed runoff indicates that timber removal is related to increased runoff during wet months and wet years, but runoff is reduced during dry months and dry years. These alterations in the hydrologic system occur at the least beneficial time because they augment high flows, whereas low flows are depleted. Such changes in runoff contribute to magnified erosion and deposition problems and increased stress for the flora and fauna that reside in and along Redwood Creek. [Key words: Redwood National Park, hydrology, watershed model, timber harvesting.]  相似文献   
9.
贺敏慧  杨保 《中国沙漠》2014,34(4):1133-1142
在全球气候变化背景下,明确评估树木生长对气候变化的响应机制,包括年际、年内径向生长变化及其物候现象,是深刻了解现在森林生态系统中树木生长状况及精准模拟其未来生长态势所必须的前提条件。另外,研究年内树木径向生长与气候因子的关系将会更加丰富当前从传统树轮气候学或树轮生态学研究中所得到的认识。然而,目前在高分辨率水平上(年内)直接观测树木径向生长变化对气候因子响应过程的方法或手段仍然有限。其中,微树芯方法以其独特的优势而得到了广泛的应用,尤其是在欧洲及北美加拿大地区,但在热带及亚洲的研究还相对较少。涉及内容除其最直接的监测树木径向生长变化外,也开展了不同方面的对比研究,如分析年龄效应、海拔效应、健康状况等对树木生长的影响。此外,研究者也在部分区域尝试了控制对比试验,如探讨了人为增温/冷却、干旱胁迫、森林抚育间伐措施是如何影响树木径向生长变化的。本文就以上各方面进行了详细评述。  相似文献   
10.
The least annual precipitation in the western interior of North America occurs in the northern Great Plains, including an area that encompasses parts of south-eastern Alberta, south-western Saskatchewan and eastern Montana. During 1999–2001, most climate stations in this region had record low precipitation. This paper examines this three-year drought in the context of historical climate records from Medicine Hat, Alberta and Havre, Montana and summer (June–July) and annual (August–July) precipitation reconstructed from standardized tree-ring widths (residual chronologies) from Pinus contorta (lodgepole pine) sampled in the Cypress Hills of Alberta and Saskatchewan and the Bears Paw Mountains of north-central Montana. Drought is operationally defined as precipitation in the lower 10th and 20th percentiles. Plots of reconstructed precipitation and cumulative departure from median values indicate a shift in climate variability prior to the twentieth century, when EuroCanadians settled in this region. The eighteenth and nineteenth centuries are characterized by sustained periods of progressively wetter and drier conditions, including prolonged drought. Various archival sources document the significant impacts of these prolonged droughts. While drought was frequent in the twentieth century, it tended to be of short duration and the impacts also were ameliorated by intervening periods of relatively high precipitation. Increasing aridity in response to global warming could expose a larger area of the northern Great Plains to the impacts of drought.  相似文献   
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