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1.
《The Professional geographer》2013,65(2):115-125
This study utilizes linguistically disaggregated region-to-region migration data between 1981 and 1986 to demonstrate that French and English speaking Canadians react differently to place attributes. A series of log transformed linear regression models suggest that the two populations differ very little in their response to traditional labor market variables but that they diverge dramatically in their response to the linguistic composition of each region. Each group prefers regions with a greater percentage of their own co-linguists, but Francophones are less sensitive than Anglophones to linguistic composition. 相似文献
2.
Trocsanyi A 《Population geography : a journal of the Association of Population Geographers of India》1994,16(1-2):1-10
"This study focuses on some aspects of the linguistic geography of Hungary.... Hungary today is a small country having a relatively homogeneous ethnic composition. However, it shows several interesting peculiarities when examined in terms of its linguistic pattern. The main goal of the study is to reveal these peculiarities and to find explanations for the great territorial differences therein. Along with a universal use of Hungarian as the first language, an east-west, a core-periphery and a north-south dichotomy is observed in respect of the second language knowledge." 相似文献
3.
The author uses Norf'k fishing ground names on Norfolk Island (South Pacific) to illustrate how toponyms can be exposed to geographic, anthropological, and linguistic scrutiny. The grammar of the names demonstrates how Norf'k, the language of the Pitcairn descendants, typifies an esoteric insider language because of its ecologically connected toponyms and pragmatic determinants. Norf'k fishing ground names vary in their linguistic form and hence in their geography and spatiality. The toponymic and linguistic landscape of Norfolk Island reveals several processes that are significant for understanding sea-based geographies and the intertwining of creole languages, other contact languages, and the environment. 相似文献
4.
当代自然地理学态势 总被引：9，自引：2，他引：7
认识自然地理学的发展态势,有助于把握学术前沿。当代自然地理学不仅研究组成自然环境的各个要素及其相互作用,研究空间过程和区域差异,也研究随时间进程而发生的各种过程及其中的各种关系,将一定时间或空间尺度上获得的结果推演到其他尺度,将自然地理学的研究成果应用于解决实际的资源、环境管理问题。国际自然地理学的新领域可以概括为自然地理系统、自然地理过程、景观与环境变化、人类活动与环境变化、全球自然地理学和文化自然地理学。中国现代自然地理学源于本土地理学并受欧美地理学和俄罗斯地理学的影响,在满足国家和社会需求方面表现突出,但在学术思想、理论和方法方面,独立的建树和自主创新尚待加强。我国自然地理学未来发展趋势是走向更加综合、站在全球变化的高度、走向更深入地揭示关键过程及其动态变化的机理机制、更加重视高新技术的运用、更加密切地为实现区域可持续发展服务,并需要加强科学思维、科学方法和科学工具的研究和创新。 相似文献
5.
This paper calls for more analysis of contemporary transnational linguistic movements. Geographers have hitherto focused on linguistic problems within states and paid less attention to issues that arise as languages, notably English, are used internationally across state boundaries. It does this by examining a conflict that arose when forces integrating the supranational European Single Market space came into conflict with a Member State's determination to protect the linguistic 'integrity' of its national territory. This conflict would appear to be a precursor of similar ones to come as languages increasingly compete in a linguistic market within an integrating Europe and a globalizing world. 相似文献
6.
Snow cover is one of the most important factors controlling microclimate and plant growing conditions for Arctic and alpine ecosystems. Climate change is altering snowfall regimes, which in turn influences snow cover and ultimately tundra plant communities. The interest in winter climate change and the number of experiments exploring the responses of alpine and Arctic ecosystems to changes in snow cover have been growing in recent years, but their outcomes are difficult to summarize because of the large variability in manipulation approaches, extents and measured response variables. In this review, we (1) compile the ecological publications on snow manipulation experiments, (2) classify the studies according to the climate scenarios they simulate and response variables they measure, (3) discuss the methods applied to manipulate snow cover, and (4) analyse and generalize the response in phenology, productivity and community composition by means of a meta-analysis. This meta-analysis shows that flowering phenology responded strongly to changes in the timing of snowmelt. The least responsive group of species were graminoids; however, they did show a decrease in productivity and abundance with experimentally increased snow covers. The species group with the greatest phenological response to snowmelt changes were the dwarf shrubs. Their abundance also increased in most long-term snow fence experiments, whereas species richness generally declined. We conclude that snow manipulation experiments can improve our understanding of recently observed ecosystem changes, and are an important component of climate change research. 相似文献
7.
The effects of grazing on the endangered Sinai Thyme (Thymus decussatus) in a hyper-arid environment
Herbivores play a key role in determining plant community composition. Historically grazing has been deemed detrimental for plants, but recent theoretical and empirical studies suggest that grazing may in fact be beneficial. Grazing is more likely to improve primary productivity in areas with a grazing history, where the plants are adapted to tolerate grazing, and also in arid environments because water stress and grazing select for comparable plant traits. Sinai Thyme (Thymus decussatus) in the arid St Katherine Protectorate of South Sinai has high apparent mortality rates and poor condition, both of which have detrimental consequences for its associated herbivores, particularly the Critically Endangered Sinai Baton Blue (Pseudophilotes sinaicus) whose larval stage feeds exclusively upon this plant. One recent conservation action banned grazing but there has been no obvious improvement in the thyme with continued high mortality, and local Bedu claim that grazing is in fact advantageous for plant health. We carried out a factorial experiment that manipulated simulated grazing, fertilizing and watering of thyme. This showed no evidence of any negative response to grazing or that watering or fertilizing had any effect either, presumably their impact is smaller than the current inter-annual variability caused by climatic fluctuations. 相似文献
8.
9.
Subfossil remains of the Pediastrum-algae group (Fam. Hydrodictyaceae) are frequently found in lake sediments, but very few studies have used them as palaeoclimate and palaeolimnological indicators. This study explored the species composition of Pediastrum assemblages in shallow floodplain lakes in northern Germany during two transitional periods from cold to temperate climate conditions (GS-2/GI-1 and GI-1/Holocene). We identified Pediastrum taxa to subspecies level and used multivariate statistics (constrained clustering, principal component analysis and redundancy analysis) to show that shifts in taxonomic composition reflected the strong Late Glacial climate oscillations. The Pediastrum assemblages indicate that climate amelioration already begun shortly before the main GS-2/GI-1 summer-temperature transition. In contrast to previous studies that identified trophic state as the main driver of change in Pediastrum species composition, we identified climate shifts and related factors as the major drivers of community change. Water depth and trophic state probably acted as secondary factors that were responsible for differences in Pediastrum response between the first and second investigated climate transitions. During cold periods, Pediastrum algae composition was controlled mainly by environmental variables, whereas during warm periods, Pediastrum assemblages may have been influenced to a greater extent by intra- and intergeneric competition. This study contributes to knowledge about ecological niches of Pediastrum species. Size-measurements on Pediastrum coenobia reveal that one response of Pediastrum algae to climate shifts probably was size change. Coenobia of Pseudopediastrum boryanum var. boryanum were significantly smaller during cold climate periods than during temperate periods. The shifts in Pediastrum species composition and coenobium size suggest this algae group has great potential for enabling palaeoecological and palaeoclimate inferences. 相似文献
10.
自然环境溶解有机碳（DOC）的组成影响着微生物群落结构,不同微生物类群对有机碳源类型的利用表现出差异。然而,纯菌株的碳源利用选择性及其和盐度的关系却仍不是很清楚。本文采用单碳源纯培养技术、聚合酶链式反应（PCR,Polymerase Chain Reaction）和相关统计方法,研究了青藏高原北部六个湖泊（洱海、青海湖、托素湖、尕海1、尕海2、小柴旦湖）沉积物中的基于不同碳源可培养细菌多样性及其与盐度的响应关系。采用七种不同类型的单碳源（甲酸钠、乙酸钠、丙酮酸钠、乳酸钠、葡萄糖、纤维素、混合氨基酸）进行培养筛选。本文共获得10个细菌分类属,它们分属于假单胞菌属（Pseudomonas）、气单胞菌属（Aeromonas）、希瓦氏菌属（Shewanella）、脱氯单胞菌属（Dechloromonas）、动性球菌属（Planococcus）、盐单胞菌属（Halomonas）、微小杆菌属（Exiguobacterium）、弧菌属（Vibrio）、交替假单胞菌属（Pseudoalteromonas）和芽孢杆菌属（Bacillus）。其中,盐单胞菌属菌株可利用本研究使用的所有碳源类型,说明这类细菌具有广泛碳代谢途径,并潜在地参与了青藏高原北部湖泊碳循环过程。所得的纯菌株利用不同碳链长度的碳源具有选择性,即随着盐度增高,某些菌株更偏向利用结构更加复杂的碳源。总之,盐度不仅影响着纯培养细菌群落多样性,而且还影响着细菌对碳源类型的选择。 相似文献
11.
多样性反映群落间物种组成的相异性,是生态学研究的热点问题。通过对乌兰布和沙漠46个样地植物群落的调查数据进行分析,运用S?rensen相异性指数衡量该地区植物群落β多样性格局,并通过主成分分析、Mantel及Partial Mantel检验等方法来衡量各环境因子差异(包括气候和土壤)和群落地理距离对该区域植物群落β多样性格局的影响。结果表明:乌兰布和沙漠植物群落之间物种组成差异较大,物种周转(βsim)主导植物群落β多样性。气候因素、土壤因素和地理距离对植物群落β多样性及其周转组分有显著影响,物种周转对其响应与植物群落β多样性保持一致。乌兰布和沙漠植物群落物种在空间上的周转是环境限制和扩散限制综合作用的结果,环境过滤对植物群落β多样性及组分的影响超过扩散限制。 相似文献
12.
There is a strong connection between cultural and biological diversity at a global scale, especially in the linguistic domain, but less is known at regional scales. Indicators of such reciprocity are found in the linguistic expression of natural elements, and their representation in the landscape through toponymy. Here we evaluate the geographic distribution of phyto-toponyms, places named after a native local flora, in Galicia, NW Spain. We created the concept of toponymic species (topo-species) for groups of places named after a plant taxon. By using different regression models assuming global effects of the variables (Ordinary Least Squares, OLS) or non-stationarity (Geographically Weighted Regression, GWR), we explored the connection of topo-species richness and diversity with environmental (river density, altitude and natural habitats density) and social (total density of toponyms, population density) factors.Topo-species richness and diversity were significantly correlated with the studied factors. Total density of toponyms, river density, altitude and natural habitats density showed significant positive values in the models, while population density had little or no effects. GWR performed better for all variables, especially for Shannon diversity index. We conclude that place names of natural elements depict human’s interaction with the environment. They are stable, spatially-explicit elements that may be used as indicators of bio-cultural diversity. In addition, they represent an intangible cultural heritage that should also be preserved. 相似文献
13.
Rafael Fernandez-Carazo Elie Verleyen Dominic A. Hodgson Stephen J. Roberts Krzysztof Waleron Wim Vyverman Annick Wilmotte 《Journal of Paleolimnology》2013,50(1):15-31
Despite the dominance of cyanobacteria in polar freshwater aquatic ecosystems, little is known about their past biodiversity and response to climate and environmental changes. We explored the use of light microscopy of microfossils, high performance liquid chromatography of the fossil pigment composition and denaturing gradient gel electrophoresis of fossil 16S rRNA genes to study past and present-day differences in cyanobacterial community structure in response to climate changes in two adjacent maritime Antarctic lakes with contrasting depths (4 and 26 m) and light climates. Light microscopy was of limited use because of degradation of cell structures. Fossil cyanobacterial pigment concentrations were below the detection limits of our method in several sediment samples in the deep lake, but abundant and diverse in the sediment core from the shallow pond, probably as a consequence of increased light availability and/or a more diverse and abundant benthic cyanobacterial flora. Total carotenoid and chlorophyll concentrations were highest in both lakes between ca. 2,950 and 1,800 cal yr BP, which coincides with the late Holocene climate optimum recognised elsewhere in maritime Antarctica. Cyanobacterial molecular diversity was higher in the top few centimeters of the sediments in both lakes. In deeper sediments, the taxonomic turnover of cyanobacteria appeared to be relatively small in response to past climate anomalies in both lakes, underscoring the broad tolerance of cyanobacteria to environmental variability. This, however, may in part be explained by the low taxonomic resolution obtained with the relatively conserved 16S rRNA gene and/or the preferential preservation of particular taxa. Our results highlight the potential of fossil DNA in lake sediments to study colonization and succession dynamics of lacustrine cyanobacteria and warrant further investigation of the factors that affect preservation of cyanobacterial DNA. 相似文献
14.
M. Amin 《Geophysical Journal International》1982,68(1):57-78
Summary. Long-period tidal records from eight ports on the west coast of Great Britain are analysed, using both the harmonic method and the response function. Time series up to 9.5 yr were used so that fine structure of certain regions of high energy in the tidal residual spectrum may be examined. This also assisted in accurate separation of tides from surges. According to the currently accepted formulation of M1 , its composition is not compatible with its actual composition in the real tide and, as such, has no useful purpose to serve in computation of predictions. Constituents Sa, Ssa, MA, and MB, are adversly affected by weather and long records are essential for their accurate separation. It has been observed that annual perturbations of S2 , similar to those confirmed in recent years for M2 , also exist but these are not readily recognisable because their speeds are the same as those of constituents T2 and R2 . These perturbations, being highly sensitive to meteorological forces, are mainly responsible for cusps or humps in the vicinity of major tidal constituents in tidal residual spectra. The relationship of radiational and gravitational tides is found to be in very good agreement with theoretical results. In summer months non-predictable variance reduces to about half of the annual variance, reflecting the regional weather conditions of summer and winter. 相似文献
15.
Jamie Peck 《The Professional geographer》2013,65(4):580-582
While linguistic diversity is an integral component of cultural landscapes, the spatial depiction of languages fails to represent all community members. Language is difficult to map and established guidelines are lacking. The perception of power conveyed is arguably the most meaningful design issue in language mapping, as most language maps inaccurately show one language per place. This research examines the cartographic visualization of linguistic diversity, contributing to our understanding of the perception of power through cartographic decisions, with the application of a linguistic diversity index. The resulting maps serve as new figures for linguistic diversity lessons in educational contexts. 相似文献
16.
前人研究显示微生物群落对有机碳源的利用具有选择性,但是纯菌株对碳源利用的选择性却不甚明了。此外,在盐湖环境中微生物出于能量的考虑可能选择性利用有机碳源以抵抗盐度渗透压。因此,盐度可能间接地影响微生物对有机碳源的利用。然而,目前类似的相关研究较少。采用单碳源纯培养技术、16S rRNA基因序列分析和相关统计方法,研究了青藏高原北部6个湖泊(洱海、青海湖、托素湖、尕海1、尕海2、小柴旦湖)沉积物中基于不同碳源可培养细菌多样性及其与盐度的响应关系。采用7种不同类型的单碳源(甲酸钠、乙酸钠、丙酮酸钠、乳酸钠、葡萄糖、纤维素、混合氨基酸)进行培养筛选。共获得10个细菌分类属的75株纯培养菌株,它们分属于γ-变形菌纲的气单胞菌属(Aeromonas)、盐单胞菌属(Halomonas)、希瓦氏菌属(Shewanella)、假单胞菌属(Pseudomonas)、假交替单胞菌属(Pseudoalteromonas)、弧菌属(Vibrio),β-变形菌纲的脱氯单胞菌属(Dechloromonas)以及芽孢杆菌纲的芽孢杆菌属(Bacillus)、微小杆菌属(Exiguobacterium)和游动球菌属(Planococcus)。其中,盐单胞菌属菌株可利用研究中使用的所有碳源类型,说明这类细菌具有广泛碳代谢途径,可能潜在参与了青藏高原北部湖泊碳循环过程。研究发现所得纯菌株对不同碳链长度碳源的利用具有选择性,即随着盐度增高,某些菌株偏向利用结构更加复杂的碳源。总之,盐度不仅影响着纯培养细菌群落多样性,而且还影响着细菌对碳源类型的选择。 相似文献
17.
This study aims to evaluate the effects of variable water flow on macroinvertebrate composition and taxon richness in a semi-arid intermittent stream. Chironomid larvae were the most abundant group of insects in the intermittent stream studied. Nevertheless, their response to flow was similar to the macroinvertebrate fauna as a whole. Macroinvertebrates were more abundant in the late wet phase and in the drying phase. A higher richness was also observed during this period, when new taxa where registered. Discharge, temperature, conductivity and dissolved oxygen were the main variables explaining the variation in richness and density of macroinvertebrate. These variables were also important in explaining the variation in community composition through time. It is suggested that invertebrates cope with the extreme intermittent flows by resilience during variable flows in the wet phase and by resistance during the dry phase. It is however important to notice that frequently high discharges drive the community to lower richness and densities, whereas the resistance during the dry phase is characterized by a taxonomic shift resultant from the survival of the few taxa that supports the initial desiccation and the opportunism of colonizing predaceous taxa overcoming non-resistant taxa. 相似文献
18.
This paper describes analyses involving patterned string bags collected in the upper Sepik in Papua New Guinea. The Mantel test and correspondence analysis were used to explore whether variability in craft repertoires exhibits any covariance with the region's complex linguistic picture, and if so, whether this relationship is more significant than any spatial autocorrelation the data may exhibit. Bag construction techniques exhibited strong spatial autocorrelation, while for colour patterns the effect was weaker. An effect for language remained for both dependents after statistical control, but colour pattern characteristics had a slightly stronger association with language overall. The weaker spatial autocorrelation for colour pattern variability is argued to be due to higher rates of dissemination facilitated by the visibility of the patterns and their compatibility with a broad range of construction techniques. The effect for language, on the other hand, is argued to have resulted from of a higher rate of inter-settlement migration along a particular stretch of the Sepik where people speak the same language. 相似文献
19.
‘Development’, resistance and the geographies of affect in Oecussi: Timor‐Leste's Special Economic Zone (ZEESM) 
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下载免费PDF全文 Michael Rose 《Singapore journal of tropical geography》2017,38(2):201-215
In 2013, it was announced that Timor‐Leste's Oecussi enclave would become the site of a special economic zone. Arid, and inhabited mostly by semi‐subsistence farmers from West Timor's Meto ethno‐linguistic group, the plan entails remaking the enclave as an industrial, transport and tourism hub. To facilitate this, in mid‐2015 the authorities began the process of clearing hundreds of indigenous gardens and homes from land slated for mega‐projects intended to make the region attractive to foreign investors. In this paper, I describe how, for many Meto, land tends to be experienced as a spiritually mediated ‘geography of affect’ (Lea & Woodward, 2010) in which questions of place, belonging, spirituality and personal fortune cannot easily be divided, a reality that raises questions about the suitability of the plan's vision of globalized and investment driven ‘development’. Drawing on Scott, I argue that in Oecussi, spirits associated with the land are not apolitical, but are sometimes perceived as acting to protect locals against powerful outsiders – a characteristically Meto ‘weapon of the weak’ that is in keeping with their previous encounters with colonial regimes. 相似文献
20.
N. G. Cameron 《Journal of Paleolimnology》1995,14(2):185-223
The representative quality of fossil diatom assemblages in the recent sediment of a lake is compared with its contemporary diatom flora. In April 1986 experimental liming of the catchment of a small acidified lake, Loch Fleet (Galloway, U.K.), produced immediate changes in water quality. Lakewater pH rose from a mean of approximately 4.5 to 6.5, and in the two year period following liming a consistently higher pH was maintained. The marked response of diatom species to changing water quality provided a means of tracing events from living communities to the fossil assemblages. Diatom periphyton and plankton were sampled during a 20 month period and archived material was used to characterise earlier diatom communities. A comparison is made between living diatom communities and diatom assemblages collected by sediment traps and from sediment cores taken during the same period.Following liming, the diatom communities were found to respond within days or weeks to the changes in water quality. There is an initial change from acidobiontic communities, dominated byTabellaria quadriseptata, to dominance by the acidophilous speciesEunotia incisa andPeronia fibula. However, in the epipsammic community the acidobiontic speciesTabellaria binalis fo.elliptica remains abundant after liming. Approximately one year after liming the abundances of species such asAchnanthes minutissima andBrachysira vitrea increase in the epilithon, epiphyton and epibryon, whilst in the epipsammonT. binalis fo.elliptica is replaced by smallEunotia spp. andAchnanthes altaica. During the latter part of 1987 and in 1988, despite a stable pH, fluctuating patterns of species abundances are seen in the epilithon, epiphyton and epibryon whilst the species composition of the epipsammon remains relatively stable. Spring blooms of the planktonic speciesSynedra acus andAsterionella formosa occur during 1988 and 1989 respectively.Sediment trapping, which began in April 1987, records shifts in species composition corresponding with those seen in the epilithon, epiphyton and epibryon and with the blooms of planktonic species. The signal from the smaller, and probably less easily transportable, epipsammic community is not so clearly discernible. Although the fundamental record of the sediment traps is one from living diatom communities, the appearance of taxa extinct during the post-liming period reflects a low, but significant level of sediment resuspension.In contrast to the rapid response of living communities and their record in sediment traps, sediment cores do not begin to reflect changes in diatom composition until about 14 months after the initial liming. The first appearance of circumneutral taxa in significant abundance occurs only approximately 17 months after liming. The delayed reaction of sediment assemblages cannot be attributed principally to a slow rate of transport from the littoral to the profundal zone. Time-averaging processes within the sediment appear to be the main cause of the lag in core response. In contrast, blooms of planktonic species are quickly reflected in the stratigraphy of cores, but indicate that a considerable degree of downward mixing occurs. Comparison of the time trajectories of whole species assemblages in living communities, sediment traps and core surface sediments shows that the direction of change is similar in all three, but that the magnitude of change is attenuated in sediment assemblages. 相似文献