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1.
Reconstructing climate change quantitatively over millennial timescales is crucial for understanding the processes that affect the climate system. One of the best methods for producing high resolution, low error, quantitative summer air temperature reconstructions is through chironomid analyses. We analysed over 50 lakes from NW and W Iceland covering a range of environmental gradients in order to test whether the distribution of the Icelandic chironomid fauna was driven by summer temperature, or whether other environmental factors were more dominant. A range of analyses showed the main environmental controls on chironomid communities to be substrate (identified through loss-on-ignition and carbon content) and mean July air temperature, although other factors such as lake depth and lake area were also important. The nature of the Icelandic landscape, with numerous volcanic centres (many of which are covered by ice caps) that produce large quantities of ash, means that relative lake carbon content and summer air temperature do not co-vary, as they often do in other chironomid datasets within the Arctic as well as more temperate environments. As the chironomid–environment relationships are thus different in Iceland compared to other chironomid training sets, we suggest that using an Icelandic model is most appropriate for reconstructing past environmental change from fossil Icelandic datasets. Analogue matching of Icelandic fossil chironomid datasets with the Icelandic training set and another European chironomid training set support this assertion. Analyses of a range of chironomid-inferred temperature transfer functions suggest the best to be a two component WA-PLS model with r 2 jack = 0.66 and RMSEP = 1.095°C. Using this model, chironomid-inferred temperature reconstructions of early Holocene Icelandic sequences show the magnitude of temperature change compared to contemporary temperatures to be similar to other NW European chironomid sequences, suggesting that the predictive power of the model is good.  相似文献   

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3.
Multi-proxy data, both lithostratigraphic and biostratigraphic, are presented from Efstadalsvatn, a lake in NW Iceland. The sequence covers the period 10,000 to 3500 14C yr B.P. The biostratgraphic data include the first Icelandic chironomid-based reconstruction of Holocene mean July air temperatures, using a Norwegian training set in the absence of modern Icelandic data. The results show that deglaciation and ecosystem development probably began before 10,000 14C yr B.P. and that July temperatures were around 4°C at ca. 9500 14C yr B.P. Temperatures then rose to ca. 8°C at the time of the deposition of the Saksunarvatn tephra (9100 14C yr B.P.), reaching ca. 10°C by 8500 14C yr B.P., high enough for the growth of tree birch, although successful birch colonisation did not take place until 6750 14C yr B.P. There is some evidence for cooling immediately preceding 9100 14C yr B.P. There is little firm biostratigraphic evidence for the 8200 cal. B.P. event, although this may be due to a relatively low resolution pollen sampling interval, but there are changes at this time in the total carbon (TC) and mass susceptibility (MS) data. Optimal temperatures and relative vegetation stability may have occurred between 8000–6100 14C yr B.P. but the chironomid assemblages indicate higher temperatures after 5000 14C yr B.P. This latter interpretation may, however, reflect delayed colonisation of thermophilous taxa and requires further investigation. There is evidence in the lithostratigraphy for greater local terrestrial instability after 6100 14C yr B.P. but it seems unlikely that this led to the redevelopment of ice in the catchment. The biostratigraphic records appear to show a degree of resistence to climate forcing throughout the early and middle Holocene. The new chironomid-based temperature reconstruction needs to be refined by further studies in Iceland, particularly the development of an Icelandic training set, but has already demonstrated the problems of paleoclimatic interpretations based on pollen and/or macrofossil evidence alone.  相似文献   

4.
A stratigraphic sequence exposed by river erosion in the foreland of Skalafellsjokull, southern Iceland, displays five lithofacies documenting glaciofluvial deposition followed by glaciotectonic disturbance and subglacial deformation. Lithofacies 1a and 1b are glaciotectonically thrust glaciofluvial outwash and subglacial deformation till respectively from an early advance of Skalafellsjokull. Lithofacies 2, massive gravels and clast–supported diamictons, documents the deposition of glaciofluvial outwash in the proto–River Skala prior to overriding by Skalafellsjokull during the Little Ice Age. During overriding, lithofacies 2 was glaciotectonically disturbed and now possesses the clast fabric and structural characteristics of G B (non–penetratively deformed) and G A (penetratively deformed) type glaciotectonites. A shear zone separates lithofacies 2 from overlying lithofacies 3, the latter possessing the clast fabric signature of a D A (dilatant) type deformation till although it was originally deposited as a discontinuous diamicton within a glaciofluvial sequence, probably as a hyperconcentrated flow, and appears to have been at least partially derived from underlying materials by glaciotectonic cannibalization. Lithofacies 4 is a glaciofluvial deposit comprising two coarseningupward sequences of gravel and diamicton. These facies have been overprinted with G B glaciotectonite and D A?B (dilatant to non–dilatant) deformation till structures and clast fabrics recording a vertical progression towards more pervasively deformed material. The sequence is capped by lithofacies 5, a two–tiered deformation till possessing the characteristics of D A and D B horizon subglacial tills previously reported from Icelandic glacier snouts. The whole sequence comprising lithofacies 2–5 represents a gravel outwash/deformation till continuum displaying variable strain signaturesproduced in response to stress induced by the overriding of Skalafellsjokull during the Little Ice Age. These signatures are dictated by the sediment rheology and a vertical strain profile for the sediment pile during glacier overriding is reconstructed.  相似文献   

5.
To explore landscape properties using language, we analyzed the semantics and associated physical properties of four generic landscape terms through spatially located microtoponyms in the Swiss canton of St. Gallen. We applied quantitative methods to physical and etymological data to understand how four common generic terms (Wald, Holz, Riet, and Moos) were used in microtoponyms in the canton. We observe that the meaningful elements associated with those generic terms characterize general properties of landscape independent of the feature type as well as specific properties linked to the feature. Moreover, using a toponym taxonomy, we compared co-occurrences of different terms (e.g., those associated with spatial relationships or vegetation) for the four generic terms. Holz, which we argue is more associated with land use than land cover, was markedly different in naming patterns from the other three generic terms, and we suggest that this was driven by a distinction between nature and culture. We conclude that the act of naming natural features is influenced not only by properties of the referent but also by broader scale landscape patterns and cognitive associations with landscape terms. Key Words: ethnophysiography, landscape, language, microtoponyms.  相似文献   

6.
Ecosystem variability must be assessed over a range of timescales in order to fully understand natural ecosystem processes. Long-term climate change, at millennial and centennial scales, is a major driver of natural ecosystem variability, but identifying evidence of past climate change is frequently confounded by human-induced impacts on the ecosystem. Iceland is a location where it is possible to separate natural from anthropogenic change in environmental archives, as the date of settlement is accepted to be around AD 874, prior to which the island was free from proven human impacts. We used a lake sediment core from Breieavatn, near Reykholt, a major farm of the Norse period in western Iceland, to examine landscape development. A change in pollen concentration in the sediments, especially the decline in Betula, indicated initial landscape degradation immediately post-settlement, whereas the chironomid fauna and reconstructed temperatures were relatively complacent during this period. The pollen evidence is corroborated by 14C analyses, which indicate an increase in older carbon entering the lake, inferred to have been caused by increased erosion following settlement. Further decreases in Betula pollen occurred around AD 1300, pre-dating a drop in chironomid-inferred temperatures (CI-T) of ~1°C over 100–200 years. The CI-T reconstruction also shows a significant cooling after ~AD 1800, likely indicative of the coldest phase of the Little Ice Age. The evidence suggests that the chironomid record was relatively unaffected by the increased landscape degradation and hence reveals a temperature reconstruction independent of human impact.  相似文献   

7.
Landscape metrics have been widely used to characterize geographical patterns which are important for many geographical and ecological analyses. Cellular automata (CA) are attractive for simulating settlement development, landscape evolution, urban dynamics, and land-use changes. Although various methods have been developed to calibrate CA, landscape metrics have not been explicitly used to ensure the simulated pattern best fitted to the actual one. This article presents a pattern-calibrated method which is based on a number of landscape metrics for implementing CA by using genetic algorithms (GAs). A Pattern-calibrated GA–CA is proposed by incorporating percentage of landscape (PLAND), patch metric (LPI), and landscape division (D) into the fitness function of GA. The sensitivity analysis can allow the users to explore various combinations of weights and examine their effects. The comparison between Logistic- CA, Cell-calibrated GA–CA, and Pattern-calibrated GA–CA indicates that the last method can yield the best results for calibrating CA, according to both the training and validation data. For example, Logistic-CA has the average simulation error of 27.7%, but Pattern-calibrated GA–CA (the proposed method) can reduce this error to only 7.2% by using the training data set in 2003. The validation is further carried out by using new validation data in 2008 and additional landscape metrics (e.g., Landscape shape index, edge density, and aggregation index) which have not been incorporated for calibrating CA models. The comparison shows that this pattern-calibrated CA has better performance than the other two conventional models.  相似文献   

8.
This article presents a study of the Icelandic landscape concept, and its meaning and embedded connotations. The present-day understanding of the concept provides the point of departure to some of the oldest preserved examples of the term. The analysis thus centres upon the sagas of Icelanders that were written in the Middle Ages. The paper reveals that in the 14th century the concept referred to morphological qualities of land, and was often associated with an aesthetic appreciation thereof. The meaning of landscape as natural scenery has been explained as the outcome of artistic articulations of social relations in the wake of the Renaissance and Romanticism. Such accounts, however, do not explain the aesthetic connotations associated with the Icelandic landscape concept in the Middle Ages, described in this article. The results of the study thus indicate that there may be more to the landscape concept within the cultural domain defined by the Germanic languages than hitherto revealed, particularly in terms of aesthetic experiences of the natural environment. Subsequently, this article emphasises the importance of identifying the culturally embedded meaning of landscape as a concept in the Icelandic context, for successful implementation of the concept in planning practices.  相似文献   

9.
This article considers the history of a particular Latvian cultural landscape, located on the coast of the Baltic Sea. Known as an aizjomi landscape, it consists of small, humanly made tilths on the seashore. These features are both physical elements and repositories of historical and cultural meaning. In one sense, through hard labor humans created the aizjomi landscape, adjusting the morphological and dynamic elements of the landscape and continually maintaining them. These human efforts made agriculture possible in the dunes, and in so doing they fashioned a means for producing a livelihood and, indeed, for sustaining life. The aizjomi landscape became a materialization of the people's day‐to‐day life in the middle and late nineteenth century and can thus be considered a “taskscape,” pulsating simultaneously with the rhythm of nature and historical events. I have analyzed empirical evidence from archival documents, reviewed ecological and historical studies, and conducted field research on specific farming practices that shaped the landscape that, in turn, shaped agricultural activities. Through a retrospective analysis I trace the development and decline of the aizjomi landscape.  相似文献   

10.
ABSTRACT

Gardens in Australia are considered an important site of heritage maintenance and negotiation for their capacity to materialise transformations in everyday life, design, lifestyles, demographics, environment, as well as social and cultural practices. In the case of conservation areas, gardens tend to be valued in terms of their closeness and potential to preserve specific historical elements. Plants in these gardens are cultivated to evoke period designs, such as Federation (c.1890–1915) and cottage gardens. In this article we turn to gardens and gardening to make sense of entanglements between cultural, historical and environmental elements, and we ask: what role do plants play in shaping our understanding of suburban heritage? To answer this question, we draw on oral histories, archival research and ethnography in Haberfield, the first model garden suburb in Australia. We show how plants channel and mediate multiple concerns that contest and extend ideas of heritage circulating in public discourse. Foregrounding the centrality of plants, this article contributes a dynamic definition of heritage that includes the entanglement of environmental stewardship and individual and collective heritage.  相似文献   

11.
This paper presents geomorphological and sedimentological evidence for three large‐scale floods to the west of the ice‐capped volcano Katla around the time of Norse settlement or Landnám (AD 870–930). These glacial outburst floods (jökulhlaups), the most recent prehistoric events in a series of Holocene floods in the Markarfljót valley, are securely dated by tephrochronology and radiocarbon dating to between c. AD 500 and c. AD 900. The environmental impact of these events would have been extensive, affecting both the highlands and about 40–50 km2 of the coastal lowlands where about 15 of the 400 or so landnám farms in Iceland were sited. An awareness of environmental conditions and landscape stability around the time of the Norse colonisation of Iceland is important to understand the earliest settlement patterns because of the different constraints and opportunities that they represent.  相似文献   

12.
Sjøholt, P. 1974. Norwegian industrial estates (SIVA) as a measure in regional development policy. Norsk geogr. Tidsskr. 28, 19–40.

This short study deals with the special role of SIVA in Norwegian regional policy. The article first examines the background to the introduction of the system into Norway, then discusses the locational requirements and decisions, emphasizing the nature of the estates as a decentralizing concentration. The second part gives information on how the estates and the individual plants function, with special emphasis on their effects on local society, both regarding other economic activities and growth of settlement.  相似文献   

13.
ABSTRACT. After the Mexican Revolution of 1910 the Mexican federal government created a communal resource‐holding institution, the ejido, to redress long‐standing land‐tenure inequality. Between the 1930s and the late 1970s, the period of active redistribution of federalized and previously private resources, half of Mexico's entire area was transferred to the ejido sector. Local ejidos became the driving political and economic force at the municipio level for agrarian reform, redistributing local power and affirming the national stamp of the Partido Revolucionario Institucional, the dominant national party of the twentieth century. Although the 1992–1993 reforms to Article 27 of the Mexican Constitution prohibited any future expansion of communal lands and allowed privatization of communal resources, few widespread privatization schemes have taken hold in the vast majority of ejidos. In this article I provide examples of this new communal framework and its implications, with illustrations based on fieldwork in the states of Guanajuato and Sonora.  相似文献   

14.
ABSTRACT

Geographic text analysis (GTA) research in the digital humanities has focused on projects analyzing modern English-language corpora. These projects depend on temporally specific lexicons and gazetteers that enable place name identification and georesolution. Scholars working on the early modern period (1400–1800) lack temporally appropriate geoparsers and gazetteers and have been reliant on general purpose linked open data services like Geonames. These anachronistic resources introduce significant information retrieval and ethical challenges for early modernists. Using the geography entries of the canonical eighteenth-century Encyclopédie, we evaluate rule-based named entity recognition (NER) systems to pinpoint areas where they would benefit from adjustments for processing historical corpora. As we demonstrate, annotating nested and extended place information is one way to improve early modern GTA. Working with Enlightenment sources also motivates a critique of the landscape of digital geospatial data.  相似文献   

15.
园林湿地——一种独特的人工湿地类型   总被引:2,自引:0,他引:2  
确认园林湿地是人工湿地的一种独特类型。定义园林湿地为:在以隔离物为边界的空间范围内,构建具有协调建筑物和文化装饰的人工水景湿地,并具有审美、文化娱乐、休憩与居住等综合功能的自然—人文复合湿地系统。园林湿地具有不同的类型和结构,按风格可分为欧美西方园林与中国园林,古典园林与现代园林。苏州园林是中国古典园林的代表,具有极高的世界文化遗产价值。园林湿地是生态城市的重要基础,对城市可持续发展具有重要意义。  相似文献   

16.
全球文化景观遗产的时空分布及列入标准分析   总被引:1,自引:0,他引:1  
经过长期的探索,自1992 年文化景观被正式列入世界文化遗产类型到2013 年的20 余年间,共有54个国家和地区的85 项文化景观遗产诞生。文章以联合国教科文组织世界遗产官网的文化景观遗产信息为数据源,统计并分析其时空分布、评价标准和遗产类别,结果显示:1)文化景观遗产数量在20 a间呈持续增长趋势,欧洲增长趋势与全球类似,亚洲增长潜力大;2)文化景观遗产集中分布在气候条件适宜人类生活且经济较发达的北半球中纬地区,欧美地区文化景观遗产数量超过全球的50%。大洲中欧洲约占全球的一半,亚洲其次,遗产大国以欧洲发达国家如意大利(6 项)、法国(5 项)、英国(4 项)和德国(4 项)为主,中国也已有4 项;3)入选的85 项遗产主要符合评价标准(iii)、(iv)和(v),说明文化景观遗产价值的评价焦点为表现遗产地独特人地关系的持续演进和延续能力;4)对51 项文化景观遗产类型进行的统计表明:具有持续特征的有机演进类约占60%,是国际主要关注类型;5)世界文化景观遗产全球共识将在未来使其空间分布相对均衡,中国尚有较大的申报空间,重构文化景观遗产类别将利于其申报和保护。  相似文献   

17.
Nilsen, R. 2014. Rural modernisation as national development: The Norwegian case 1900–1950. Norsk Geografisk TidsskriftNorwegian Journal of Geography Vol. 68, 50–58. ISSN 0029-1951.

The aim of the article is to explain the maintenance of a pattern of scattered rural settlement in Norway during industrialisation and modernisation. The ‘master narrative’ of Norwegian transformation, based on the development of waterpower and the metallurgical and fertiliser industries, is only one of three narratives that can be told about the national transformation in the 20th century. A second narrative concerns the modernisation along the coast, and a third concerns the development of a varied, mostly rural, manufacturing and import-substituting industry. It is suggested that this attempt at rewriting the history of Norwegian modernisation can do what the master narrative does not do, namely explain the transformation from a poor to a rich society while more than half of the national population continued to live in rural areas.  相似文献   

18.
王云才  韩丽莹 《地理研究》2014,33(1):143-156
在城镇化、现代化和商业化快速发展的今天,传统文化景观的破碎化已成为传统地域文化景观的重要空间特征和现象,破碎化直接催生了传统文化景观空间的孤岛化现象,直接影响着传统地域文化景观的整体性,成为传统文化景观整体性保护的重要障碍。本文以苏州市甪直镇为例,在分析区域特征及对当地居民进行问卷调查的基础上,通过构造孤岛化评价指数,评价甪直古镇传统文化景观的格局的综合特征和景观孤岛化现象、特征及形成过程。在传统文化景观孤岛化评价的基础上,通过确定保护圈层、构建文化景观遗产廊道和景观生态网络格局,实现传统文化景观空间的拓展、连接和传统文化景观与缓冲空间的有机复合,成为传统地域文化景观区域性整体保护的空间模式。  相似文献   

19.
The short article makes a small selection of early German literature containing the term ‘cultural landscape’ accessible for an English-language readership with the aim of enabling a broader discussion of the term. After a brief overview of the usage of ‘cultural landscape’ in geographical research, four German authors and their publications are presented. Carl Ritter appears to have been the first to use Culturlandschaft, in 1832. He was followed by Carl Vogel in 1851, Joseph Wimmer in 1882 and 1885, and Friedrich Ratzel in 1893. Analysis of their use of ‘cultural landscape’ reveals different dimensions of the term: a developmental perspective on cultural landscapes, i.e. cultural landscapes developed from natural landscapes; an opposition of nature and culture; and an understanding of cultural landscape as agricultural or park landscape. The process of cultivation is described with words with a positive connotation. The comparison of these dimensions with recent geographical literature shows that long-standing ideas continue to influence present-day usage.  相似文献   

20.
陕西传统村落文化遗产景观基因识别   总被引:4,自引:1,他引:3  
文化遗产景观是地域文化的符号表征,文化遗产景观基因则是地域文化代际传承的基本“遗传”单位和文化遗产景观形成的决定性因子。目前文化遗产景观基因研究已成为文化地理学的重要方向之一。通过识别与提取隐藏在文化遗产景观内的文化基因,可反映出地域文化的基本特质。传统村落是最具代表性的地域文化遗产景观,整体上延续和传承了中国优秀的传统文化,并集中体现在传统村落内的文化遗产景观之中,对传统村落进行遗产性景观基因识别研究可揭示地域文化的人文地理性和传统村落的社会文化性。基于地域文化遗产景观基因理念,以陕西省35个代表性传统村落为例,首先从宏观和中观尺度,分析了传统村落遗产性景观的文化环境特征;其次从微观视角,建立了传统村落文化遗产景观基因识别指标体系,综合运用景观基因识别与提取方法,对传统村落文化遗产景观的基因特征进行分析,识别出传统村落的地域文化特质。本文旨在从文化地理学的视角认识和保护传统村落文化遗产景观,为实现传统村落的文化复兴提供科学依据。  相似文献   

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