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1.
The article examines the risk of water shortages due to the climate change on Leu-Rotunda Plain, which is part of Oltenia Plain in Romania. The region has been exposed to several extreme climatic phenomena, mostly droughts, which has created several problems related to water quality and quantity. The authors defined climate change scenarios using two regional climate models. Water resources under climate change were estimated by a regional numerical groundwater model covering a deep aquifer. The water demand components were estimated for households, industries, services, and livestock, based on specific socio-economic assumptions. A non-probabilistic risk assessment, using simplified fuzzy sets mathematics, was used to estimate water supply, water demand, and the consequences of water shortages. The results of the study revealed significant vulnerability in the water supply, a limited territorial expansion of sewerage networks, an expected increase in households’ demand, an expected increase in industrial and services water demand, a relatively stable demand for water for livestock farming, and an important water shortage in the study area. The authors conclude by highlighting a set of actions to mitigate the risk of the potential crisis.  相似文献   

2.
A regional examination of representations of geographical ecclesiastical features (boundaries, churches, and land use) in northern Scandinavia during the High Middle Ages was performed, using a peripheral parish as a single case. The analysis was based on historical maps, processed using microhistory and retrogressive approaches, and guided by theories of territoriality and landscape. The results showed that some churches were built on outfields, that landownership and prehistoric burials were clustered in two different areas, and that parish boundaries were often located in uninhabited forests between settlements and were sometimes moved. These results are discussed within the context of symbols, relations, and identity, which are complementary to explanations of centrality such as minimum travel distance. The author concludes that this indicates that, based on kinship networks, farmers from the settlement areas built the churches on jointly owned or managed land, which symbolises their collective effort – their sense of ours. Furthermore, settlement desertion during the agrarian crisis is probably the reason behind later changes in parish boundaries.  相似文献   

3.
ABSTRACT

In recent years cleantech (clean technology) clusters have emerged in many industrialized regions. Cleantech clusters are heralded as a key solution in the transformation toward a greener economy, with the potential to foster regional economic growth while simultaneously mitigating environmental challenges. Despite witnessing a growing tendency for cleantech activities to be organized in clusters, the research literature remains rather vague on what cleantech clusters are and how they emerge. The author therefore explores these questions with the use of empirical data from three internationally recognized cleantech clusters: (1) Cleantech San Diego, in Southern California, USA, (2) Green Tech Valley, located in the province of Styria, Austria, and (3) Sustainable Nation Ireland, located in the Dublin region, Ireland. The data and information used in the article were derived from empirical accounts sourced from existing literature, secondary data sources, on-site observations, and face-to-face interviews carried out between October 2015 and June 2016. The findings show that the cleantech clusters can be perceived as knowledge, innovation, and collaboration clusters that span industrial and institutional boundaries. The formation of the cleantech clusters is largely the outcome of strategic leadership on the one hand, and place-specific conditions and local capabilities on the other hand.  相似文献   

4.
Whereas refugees and larger immigrant groups’ integration in the Norwegian labour market has received considerable research attention, less is known about the labour market integration of small, non-refugee immigrant groups from West African countries such as Ghana. The purpose of the article is to examine the role of social networks and social identities for the differentiated labour market integration outcomes among Ghanaian immigrants in the city of Bergen. Based on data produced through in-depth interviews, participant observation and informal conversations, the authors argue that Ghanaian immigrants’ ability to obtain jobs is determined by more than simply having the appropriate educational and language qualifications, and largely depends on having favourable social identities and being embedded in social networks beyond the Ghanaian immigrant community. They find that those who mainly relied on Ghanaian networks found it difficult to circumvent labour market hindrances and they predominantly obtained menial jobs. The authors conclude that Norwegian job-seekers networks played a crucial role in the immigrants’ opportunities and for potential Norwegian employers’ perception of their employability, especially in professional and semi-professional jobs.  相似文献   

5.
The effects of global climate change include more extreme weather events that harm lifeline infrastructure such as road access. The questionnaire-based study takes a novel natural experiment approach to subjective personal experiences and perceptions of lifeline vulnerability in two seaside communities in Norway that have been sporadically isolated due to avalanches, heavy snowfall, and/or snowdrifts. The enquiry aims at filling a research gap on sudden winter climate-induced disconnections and road travel hazards in advanced societies. The results show that weather-induced road closures lead to worries about road travel and practical problems, but also that many people are able to adjust to reduce their vulnerability. The authors concluded that community characteristics such as available services and social and human capital are important for understanding people’s vulnerabilities, worries, and hazard preparedness.  相似文献   

6.
Transborder property ownership is a growing trend in different parts of the world. In Finland, Russians make up the biggest group of foreign buyers. The article examines Russian recreational property purchases in Eastern Finland, where South Savo Region is subject to the heaviest flow of Russian purchasers. Russian purchases of second homes have been the subject of a broad social debate dominated by negative attitudes towards the phenomenon. Fears of place change and displacement have been among the main concerns. The authors reveal how arguments presented in the social debate on Russian ownership correspond to the distribution of Russian properties in South Savo. Statistics for the period 2003–2012 and GIS methods were used to analyse the distribution and density of Russian recreational properties in the region. Statistical modelling uncovered some factors that affected the location of the properties. The findings indicate that the arguments presented within the social debate have only partially derived from the distribution patterns of Russian properties. The authors conclude that a combination of factors, including distances from the border and services as well as preferences for waterside locations, have influenced the choice of location of Russian properties and led to concentrations in certain areas.  相似文献   

7.
8.
The article examines an alternative food network evolution in the post-communist context in Czechia in general and farm shop developments in particular. The study is based on semi-structured interviews with farm shopkeepers operating in Czechia. The results revealed that the development of the farm shop network was significantly shaped by the communist past of the country. While consumers’ demand for quality food contributed to the initiation of developments in local food movements such as farm shops in Czechia, the inconvenient structure of the farming sector, comprising a limited number of small-scale farmers, hindered the development. Although the farm shops usually operate as middlemen by reselling goods produced by a range of farmers, farm shopkeepers expressed significant awareness of the sustainability principles of the local food concept and dissociated themselves from unethical practices of large retailers. Nevertheless, the author finds that the local concept is used in a flexible manner to meet customers’ demands. Despite obstacles faced by farmers when developing their own farm shops, there is significant potential in ‘Czech-type’ farm shops operating solely as retailers. However, the author concludes that the threat of the diversion from the sustainability principles of the local food concept should not be neglected.  相似文献   

9.
ABSTRACT

The authors employ the global production network (GPN) approach to analyse the development of the renewable energy sector. Through a case study of the development of a Hywind floating offshore wind project (Hywind) across two oil and gas economies, namely Norway and Scotland, the paper sheds light on the key drivers and role of core GPN actors. Methodologically, the authors investigate the process from both ‘inside-out’ and ‘outside-in’ perspectives, referring to the efforts of firms expanding into overseas markets and the efforts of host countries to attract investment from outside their territories. The analysis shows how the configuration of extractive production networks is shaped by the interactions between the network development practices of firms and the market development strategies of host states. The authors conclude that the distinct materiality of floating wind power technology shapes the territorial configuration of the production network by enabling its spatial extension across a range of locations. By contrast, existing research on other extractive sectors has emphasized the spatially constraining effects of materiality (Bridge 2008).  相似文献   

10.
The study objective was to analyse how capitalized and non-capitalized resource rents act as mechanisms of innovation in nature-based tourism within a centre–periphery context dominated by distance, instability, and dependency. The authors studied 55 out of 64 businesses engaged in tourism in Nordkapp Municipality in Norway in the period 2002–2012. Data were collected from a survey, interviews, and empirical observations, and then analysed using both deductive and inductive methodological approaches. The main findings were that tourism in the Nordkapp Municipality had suffered from a lack of local innovation initiatives caused by the capitalized resource rent of tourism to North Cape and its leakage. Nevertheless, local tourism had increased partly because of the inclusion of new and more attractive products, due to the open-access, non-capitalized resource management in fishing tourism that operated simultaneously with the closed and capitalized context of North Cape tourism. The authors conclude that this open-access regime of fishing tourism stimulated innovation and further development of coastal tourism, and even affected traditional North Cape tourism. Non-capitalized resource rent had not leaked out because it had not been collected by external companies and because it had acted as an innovation mechanism on the periphery.  相似文献   

11.
ABSTRACT

The impact of building cycles on recent expansions of Athens was assessed under the hypothesis that non-linear paths of urban growth result from sequential phases of economic growth and decline. Changes over time in building activity were examined by considering indicators derived from a local-scale analysis of building permits issued by Greek municipalities between 1990 and 2016. Relevant socioeconomic forces shaping spatio-temporal variability in building activity were identified by analyzing contextual indicators through inferential techniques and multivariate analysis. The results showed distinctive responses of real-estate local markets to economic cycles at the local scale in Athens, allowing for identification of short-term and long-term urban dynamics characteristic of expansion and recession waves. The most sensitive indicators to economic cycles in Athens were density of new buildings, average floors per new building, density of building additions, and number of building permits per inhabitant. Infrastructure-driven development, as a result of the 2004 Olympic Games, has produced relevant alterations in short-term patterns in the construction market, resulting in spatially-complex urbanization trends. The author concludes that local-scale indicators derived from building permit data provide insights into progressively complex dynamics of urban growth, with implications for regional planning and the design of sustainable development practices.  相似文献   

12.
1 Introduction High mountain landscapes above the tree-line are often regarded as close to nature, although human impact has obviously changed the environment, partly exceeding its carrying capac- ity (L?ffler, 2000). Due to their fragility regarding expe…  相似文献   

13.
小气候、雪盖及土壤湿度对高山生态系统功能的影响   总被引:1,自引:0,他引:1  
1 Introduction High mountain landscapes above the tree-line are often regarded as close to nature, although human impact has obviously changed the environment, partly exceeding its carrying capac- ity (L?ffler, 2000). Due to their fragility regarding expected environmental changes and an increasing land use pressure in many regions, high mountain landscapes recently became a major focus within the discussion on a sustainable development in a worldwide (Messerli and Ives, 1997), and regional p…  相似文献   

14.
The dynamics of water and energy fluxes in the high mountains of central Norway was studied along micro-spatial topographic gradients in different altitudes and regions of the Scandes. Landscape ecological processes like snow accumulation during winter, snow melting, evaporation, percolation, soil moisture variability and temperature variations were quantified. Combining spatio-temporal data on physical environment functioning and vegeta-tion patterns resulted in a process-oriented characterisation of high mountain ecosystems. Extensive data from long-term measurements were synthesised illustrating the influence of micro-climate, snow cover, and soil moisture on high mountain ecosystem functioning. The results reveal that the micro-climatic impact on the vegetation is predominantly determined by snow cover overlaying soil moisture gradients. Water only becomes superior where near-surface water saturation and flooding occur. A lack of soil moisture availability was not found during any time of the year even under driest site conditions. Contrasting literature, the Norwegian mountain vegetation was found to be interpreted by environmental variable con-stellations excluding drought stress.  相似文献   

15.

This paper describes one geometrical method of simulating the spatial distribution of snow cover. Geographical Information Systems (GIS) and precise Digital Elevation Model (DEM) were used in the simulation. The model is based on empirical parameters called coefficients depending on slope aspect and inclination. As a result, this model predicts that windward convex terrains remain snow-free during winter. This snow cover distribution was validated by usage of an air photograph taken in early spring, and the distribution of vegetation patches which represent the outer fringes of snow covered areas. Low ground temperatures together with high DC resistivities, which suggest the presence of permafrost, were identified in simulated snow-free areas.  相似文献   

16.
In this paper, a variation series of snow cover and seasonal freeze-thaw layer from 1965 to 2004 on the Tibetan Plateau has been established by using the observation data from meteorological stations. The sliding T-test, M-K test and B-G algorithm are used to verify abrupt changes of snow cover and seasonal freeze-thaw layer in the Tibetan plateau. The results show that the snow cover has not undergone an abrupt change, but the seasonal freeze-thaw layer obviously witnessed a rapid degradation in 1987, with the frozen soil depth being reduced by about 15 cm. It is also found that when there is less snow in the plateau region, precipitation in South China and Southwest China increases. But when the frozen soil is deep, precipitation in most of China apparently decreases. Both snow cover and seasonal freeze-thaw layer on the plateau can be used to predict the summer precipitation in China. However, if the impacts of snow cover and seasonal freeze-thaw layer are used at the same time, the predictability of summer precipitation can be significantly improved. The significant correlation zone of snow is located in middle reaches of the Yangtze River covering the Hexi Corridor and northeastern Inner Mongolia, and the seasonal freeze-thaw layer exists in Mt. Nanling, northern Shannxi and northwestern part of North China. The significant correlation zone of simultaneous impacts of snow cover and seasonal freeze-thaw layer is larger than that of either snow cover or seasonal freeze-thaw layer. There are three significant correlation zones extending from north to south: the north zone spreads from Mt. Daxinganling to the Hexi Corridor, crossing northern Mt. Taihang and northern Shannxi; the central zone covers middle and lower reaches of the Yangtze River; and the south zone extends from Mt. Wuyi to Yunnan and Guizhou Plateau through Mt. Nanling.  相似文献   

17.
青藏高原东南部海拔高,地形复杂,云量大,准确掌握该地区的积雪分布特征对于积雪灾害防治非常重要。论文以2013—2019年冬季积雪积累期云量符合要求的35景高分一号(GF-1)影像为基础,将全色影像和多光谱影像融合为2 m分辨率影像,通过目视解译获取了研究区积雪的空间分布特征,结合改进后的30 m分辨率SRTM DEM,探讨了地形对积雪分布的影响。结果表明:积雪像元在研究区范围内占比为33.1%。积雪的垂直分布特征明显:积雪在高程带4000~5000 m(高海拔)处分布较集中,积雪面积占比为18.1%;在高程带0~2000 m、2000~3000 m和6000~7000 m处积雪面积占比均不到0.1%。积雪在北坡、东北坡的分布比例较高,均为15%以上;在南坡、西坡、西南坡、东南坡分布比例较低,均为10%左右。将基于GF-1影像获取的积雪分布分别与同日获取的根据MODIS V6积雪产品计算的积雪比例(MODIS FSC)和积雪分布的对比表明,64.4%的MODIS FSC像元绝对误差不超过10%,MODIS积雪分布产品对含雪像元的漏分率和误分率平均为33.8%和32.7%,说明MODIS积雪产品在研究区的精度还具有较高的不确定性,其对低覆盖积雪反演的精度较差。这表明利用MODIS积雪产品研究青藏高原东南部积雪的时空变化特征时还需要对其积雪反演算法进行改进,同时亟需加强地面观测和基于多源遥感数据的积雪研究。研究结果可为青藏高原东南部雪冰灾害防治提供支撑。  相似文献   

18.
Coastal zones play a major role in the conservation of marine ecosystems and the sustainable use of resources not only because of their special geographical environment but also because of their high temporal and spatial variability. With the development of urbanization, the exploitation and utilization of coasts have become important issues in the debate. To evaluate variations in the intensity of the land resource exploitation of coastal zones, an index- based model has been proposed in this paper, and coastal Vietnam has been established as the study area. The model is based on four normalized indexes to realize rapid evaluation of the spatial distribution of the exploitative intensity after zoning. The model was established to characterize the different exploitative intensities in different segments of the coast and to graphically present a sequence of decision choices for decision-makers. The results are as follows. (1) The simplicity and rapidity of the index operations can address the fast-changing characteristics of coastal exploitation and meet the desired precision. (2) The choices of the landward buffers fit well with the banded characteristics of the coastal zone. The buffers are horizontally divided into equidistant subregions, which can quantify the spatial differentiation of the exploitative intensity along the coast and perpendicular to the coast. (3) The average exploitative intensity is low, and the proportion of area that is to be exploited accounts for approximately 50%.Considering its spatial variation from north to south, the land exploitative intensity in the north is higher than that in the south. Compared to the intensity of land resource exploitation in the 20 km and 10 km buffers, the land exploitative intensity in the 5 km buffer is higher. The state of the intensity of land resource exploitation and how it can be used by stakeholders to manage coastal resources are then discussed.  相似文献   

19.
Diatom assemblages preserved in sediment cores from closed-basin lakes can provide high-resolution records of past hydrologic and climatic conditions, including long-term patterns in the intensity, duration, and frequency of droughts. At Moon Lake, a closed-basin lake in eastern North Dakota, a comparison of diatom-inferred salinity and the precipitation-based Bhalme-Mooley Drought Index (BMDI) over the last 100 years was highly significant, suggesting that the diatom record contains a sensitive archive of past climatic conditions. A sub-decadal record of inferred salinity for the past 2300 years indicates that extreme droughts of greater intensity than those during the 1930s 'Dust Bowl' were more frequent prior to A.D. 1200. This high frequency of extreme droughts persisted for centuries and was most pronounced from A.D. 200–370, A.D. 700–850 and A.D. 1000–1200. A pronounced shift to generally wetter conditions with less severe droughts of shorter duration occured at A.D. 1200. This abrupt change coincided with the end of the 'Medieval Warm Period' (A.D. 1000–1200) and the onset of the 'Little Ice Age' (A.D. 1300–1850).  相似文献   

20.
Studying the winter survival of forage grasses under a changing climate requires models that can simulate the dynamics of soil conditions at low temperatures. We developed a simple model that simulates depth of snow cover, the lower frost boundary of the soil and the freezing of surface puddles. We calibrated the model against independent data from four locations in Norway, capturing climatic variation from south to north (Arctic) and from coastal to inland areas. We parameterized the model by means of Bayesian calibration, and identified the least important model parameters using the sensitivity analysis method of Morris. Verification of the model suggests that the results are reasonable. Because of the simple model structure, some overestimation occurs in snow and frost depth. Both the calibration and the sensitivity analysis suggested that the snow cover module could be simplified with respect to snowmelt and liquid water content. The soil frost module should be kept unchanged, whereas the surface ice module should be changed when more detailed topographical data become available, such as better estimates of the fraction of the land area where puddles may form.  相似文献   

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