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1.
The Norwegian-Soviet boundary is of unusual interest for several reasons. Its long history involves the territories of Norway, Sweden, Finland and Russia and has been complicated by the migration of nomadic Lapps1 and by changing Norwegian sovereignty (in relation to Denmark and Sweden), Finnish sovereignty (in relation to Sweden and Russia) and by revolutionary changes in the government of Russia. The boundary was also closely concerned in events at the end of the first World War, in the so-called ”Winter War” between Finland and the Soviet Union (1939—10), in the Nazi occupation of Norway and Finland (1940—44), and the subsequent liberation of northeastern Norway and Finland by Soviet armies late in 1944.

The region adjacent to the boundary is significant for other reasons: It contains valuable resources — especially iron ore and nickel; the Pasvik River has potential value for hydro-electric development, and for floating lumber northward toward a region where wood is scarce; there are relatively fertile soils and a mild climate whereas the surrounding area is generally unproductive. The Pasvik valley is the natural trade route between northern Finland and the open waters of Varanger Fjord, and conversely, from the Kirkenes area to southern Scandinavia.  相似文献   

2.
The Norwegian area frame survey of land cover and outfield land resources (AR18X18), completed in 2014, provided unbiased statistics of land cover in Norway. The article reports the new statistics, discusses implications of the data set, and provides potential value in terms of research, management, and monitoring. A gridded sampling design for 1081 primary statistical units of 0.9 km2 at 18?km intervals was implemented in the survey. The plots were mapped in situ, aided by aerial photos, and all areas were coded following a vegetation type system. The results provide new insights into the cover and distribution of vegetation and land cover types. The statistic for mire and wetlands, which previously covered 5.8%, has since been corrected to 8.9%. The survey results can be used for environmental and agricultural management, and the data can be stratified for regional analyses. The survey data can also serve as training data for remote sensing and distribution modelling. Finally, the survey data can be used to calibrate vegetation perturbations in climate change research that focuses on atmospheric–vegetation feedback. The survey documented novel land cover statistics and revealed that the national cover of wetlands had previously been underestimated.  相似文献   

3.
Traditional land use systems are threatened by land use intensification and resulting land cover transitions in northern areas. This article examines cumulative land cover changes and their impacts on reindeer grazing grounds in the Kyrö reindeer herding district in northern Finland. Land cover transitions were studied using Landsat TM and OLI images and topographic maps. The results showed that the herding district has experienced notable land cover changes during the past decades, and most of these changes were directly related to forestry. The proportion of continuous coniferous forests of the total forest cover declined from 92% to 78% between 1987 and 2013. Approximately one third of the forests outside current conservation areas were disturbed by forest management by 2013, and remaining forests were notably more fragmented than forests within conservation areas. The extent of the road and path networks expanded considerably between 1960s and 2010 as a result of increasing logging and tourism. Accumulation of disturbances gradually results in loss of key resources and declined quality of the landscape mosaic from the reindeer herding perspective, which can pose a serious threat to long-term sustainability of the livelihood. Rapid land cover changes in non-protected areas highlight an increasingly important role of conservation areas in maintaining resources for reindeer husbandry in the face of intensifying land use. Sustainable management of resources outside conservation areas requires careful participatory planning and efficient cumulative impact assessment of different land use activities.  相似文献   

4.
Öje Danell 《Polar research》2000,19(1):111-115
Emerging out of small-scale reindeer farming, large-scale reindeer husbandry in Sweden and Norway was developed to counteract resource scarcity caused by depleted wild reindeer numbers and human population growth above what the former subsistence economy could sustain. Current numbers of reindeer are likely lower and fluctuate less than before wild reindeer were depleted and reindeer husbandry started on a large scale. Productivity is about 7-8 kg of meat per head in winter stock. Current problems arise from a multitude of circumstances, some of them related to the problems of practising a subsistence type of living in close connection with a modern industrialized society. Problems include: low production, typical for harsh conditions and use of an unimproved animal stock; the inability to support a modern standard of living solely from reindeer; the collective access to grazing grounds which makes internal management difficult; unclear legal rights resulting in conflicting interests with other land users and formal owners; and the relatively low number of people directly involved in reindeer husbandry. Possible long-term consequences are marginalization and the loss of land use rights, with negative consequences for the Saami as an indigenous people. Reindeer husbandry research addresses these problems by integrating human-ecological and socio-economic aspects with traditional natural science orientated research on reindeer husbandry problems. This research is funded by a multitude of sources. Independently of this, research is conducted on Saami life and culture in relation to reindeer husbandry at various universities, especially within social sciences and arts.  相似文献   

5.
The objective of this paper is to examine a method for estimation of land cover statistics for local environments from available area frame surveys of larger, surrounding areas. The method is a simple version of the small-area estimation methodology. The starting point is a national area frame survey of land cover. This survey is post-stratified using a coarse land cover map based on topographic maps and segmentation of satellite images. The approach is to describe the land cover composition of each stratum and subsequently use the results to calculate land cover statistics for a smaller area where the relative distribution of the strata is known. The method was applied to a mountain environment in Gausdal in Eastern Norway and the result was compared to reference data from a complete in situ land cover map of the study area. The overall correlation (Pearson’s rho) between the observed and the estimated land cover figures was r = 0.95. The method does not produce a map of the target area and the estimation error was large for a few of the land cover classes. The overall conclusion is, however, that the method is applicable when the objective is to produce land cover statistics and the interest is the general composition of land cover classes - not the precise estimate of each class. The method will be applied in outfield pasture management in Norway, where it offers a cost-efficient way to screen the management units and identify local areas with a land cover composition suitable for grazing. The limited resources available for in situ land cover mapping can then be allocated efficiently to in-depth studies of the areas with the highest grazing potential. It is also expected that the method can be used to compile land cover statistics for other purposes as well, provided that the motivation is to describe the overall land cover composition and not to provide exact estimates for the individual land cover classes.  相似文献   

6.
The coastal heath region along the western coast of Norway, dominated by Calluna vulgaris, is undergoing rapid change. Vegetation changes are caused by changes in management, including reduced frequency or abandonment of periodic heath burning and reduced cutting and grazing. The islands of Froan, in the outermost part of Sør-Trøndelag County in mid-western Norway, are dominated by coastal heath in a state of recession due to reduced traditional land use. The coastal heath is acknowledged as vulnerable and valuable by national environmental authorities, and local landscape management is supported by different national subsidies. The authors mapped the vegetation on Froan and used rule-based GIS-modelling to predict the relative potential for future vegetation changes. The model was based on a range of map layers, including management themes such as history of heath burning and peat removal, current practices of sheep grazing, and also themes derived from the vegetation map, such as soil nutrients, soil moisture and present management status. The resulting model output provides relative probabilities of future changes under different land-use scenarios, and highlights where management efforts should be focused in order to maintain the traditional landscape character.  相似文献   

7.

In Norway, on-site biological surveys precede the designation of nature reserves. Although many nature conservation areas have been affected by past human use (e.g. cattle grazing, timber harvesting), a typical biological survey may fail to portray the extent of human influence on biodiversity and vegetation dynamics. In 1984, Hystad forest (western Norway) was made a nature reserve after botanists interpreted the ecosystem 'close to untouched'. It was thought best to leave the forest alone, so no management plan was developed. It was later realized that the vegetation was changing, but the reason was not obvious. I gathered and analyzed further biological data plus information on land-use history from varied sources (e.g. cadastral maps, archive material and oral histories). The area has undergone a series of transformations since the 17th century. The present forest is no more than 100 years old, and extensive parts are much younger. The initial survey underestimated the extent of cultural impact and failed to predict vegetation change subsequent to reserve establishment, whereas a historical-geographical approach reveals that the vegetation is in a state of transition, driven primarily by a change from active farming to farm abandonment. Planning for conservation must recognize past as well as present human use of the landscape to anticipate consequent land cover responses.  相似文献   

8.
全球及区域模式中陆面过程的地表植被覆盖分类方法   总被引:1,自引:0,他引:1  
全球和区域尺度上陆面生态系统与气候密切相关。全球和区域模式的发展对于我们认识气候与陆地生态的变化起到重要作用。在这些模型中,植被覆盖是影响大气-植被间热量、水分和CO2等交换的重要陆面参数。在分析了陆地植被覆盖分类原理基础上,介绍了目前全球不同植被覆盖分类方案,包括基于地基观测的植被分布、基于生物气候特征的分类方案(如:Holdridge的方案);特别近年来陆面过程试验表明,各种遥感数据源(如:NOAA—AVHRR,EOS—MODIS,Landsat—TM)等为我们提供了有利的工具来监测全球植被动态,完善植被分类,并且采用高时空分辨率的全球土地覆盖状况特征,在不同时空尺度揭示植被-大气相互作用。本文分析了代表性的3种基于卫星遥感技术的陆面植被分类方案,分别是BATS(18类)、SIB(9类)、SIB2(12类)和BIOME—BGC(31类)陆地模式的植被覆盖分类方案.最后分析了目前可用于全球植被覆盖分类的新的遥感数据库。  相似文献   

9.
Cross-border shopping and tourism are worldwide phenomena, appearing at any border with at least some degree of permeability. The authors investigate the range of cross-border shopping and tourism activities practised by Russians at two of the EU’s external borders, one between Finland and the Leningrad Oblast, and the other between Poland and the Russian exclave of Kaliningrad Oblast. The study is based on research conducted in the Polish–Russian and Finnish–Russian border regions between 2013 and 2015, when the authors held interviews, administered survey questionnaires, and engaged in participant observation. The information was supplemented with data from the Finnish and Polish Border Guard services. Based on the results of the fieldwork, the authors argue that cross-border shopping and tourism are often combined during the same trip, and thus constitute a specific form of cross-border activity. Their study sheds light on how cross-border shopping tourism depends on and is interconnected with more than just the factor of the non-availability of goods and services. They conclude that cross-border shopping at the Polish–Russian border and the Finnish–Russian border has become more like a Western European practice, namely shopping for pleasure.  相似文献   

10.
参照《中国植被》中的植被分类体系,结合野外考察结果,建立了适合中国西北农牧交错带的植被分类体系。以覆盖研究区的多幅Landsat影像为基础,按“分层分类,逐层验证”的思路,实现了对研究区植被信息的提取。提取时,先利用完全约束的最小二乘模型对遥感影像进行混合像元分解方法,将整个研究区划分为植被区和非植被区;在植被区,基于光谱特征、纹理特征和地形特征,构建CART决策树,获得了乔木林、灌丛和草原等7种主要植被型组;在植被型组内,基于不同植被类型NDVI的季节差异特征,构建NDVI差值比值指数 (NDVI_DR),将乔木林和灌丛区分为常绿和落叶植被型,使用温度植被干旱指数(TVDI),将草原进一步区分为荒漠草原、典型草原和草甸草原3种类型,从而得到各个植被型的空间分布范围。经验证,最终分类的总体精度能达到79.51%,kappa系数为0.773。采用的分类方法充分利用了遥感数据既有的光谱信息和纹理信息,同时辅以地形信息。实践结果表明,分层分类和多种指标相结合的方法可以有效实现对影像跨幅的、以复杂镶嵌结构为主要特征的农牧交错带植被信息提取,精度较高,技术可行。  相似文献   

11.
In this paper we discuss how low spatial resolution (1 km) ERS ATSR-2 and NOAA AVHRR satellite data were used to map and monitor changes in the grazing vegetation of the Badia region of Jordan. This area is typical of many arid zone grazing areas, comprising sparse vegetation and highly reflective soils. These two factors were found to severely limit the usefulness of satellite-derived vegetation indices that are frequently used to map and monitor vegetation in more temperate areas. Furthermore, the relationship between vegetation indices and percentage vegetation cover was found to be site-specific, thus reducing their application for large-scale vegetation monitoring. As an alternative, a hybrid geometric optical/empirically based model was developed for the area. This was based on the illumination geometry and reflectance values from the red and near-infrared scattergram of the satellite images. The output of the model was a series of maps indicating percentage vegetation cover for different dates and these were used to construct maps showing areas of vegetation change. Strong correlations (r2=0.837) were found between estimates of percentage vegetation cover derived from the model, and measurements made at a series of 16 field sites in the area. The use of geometric optical models based on satellite imagery improves the ability to map areas of grazing vegetation in arid areas such as the Badia and provides a good alternative to the use of vegetation indices.  相似文献   

12.
基于MODIS的土地覆盖遥感分类特征的评价与比较   总被引:2,自引:0,他引:2  
选取华北地区为研究区,利用MODIS遥感数据多光谱、多时相优势进行分类特征提取,依据土地覆盖分类特征如地表反射率、植被指数、纹理特征等,并对这些分类特征分别从光谱维、时间维、空间维三个角度进行阐述,结合DEM数据,使用最大似然法进行土地覆盖遥感分类特征的评价与比较。结果表明,不同分类特征对分类精度影响不同,将多种分类特征结合能够有效提高区域尺度土地覆盖分类精度,但分类特征的加入不一定能提高某些类别的分类精度。  相似文献   

13.
基于遥感数据的元江县植被/土地利用类型研究   总被引:1,自引:5,他引:1  
元江县山区面积占全县总面积的96.8%,垂直高差达2253m,地形复杂,植被类型存在明显的垂直分布。只用一个解译体系来解译这一有较大差异地区的影像是有困难的。因此本研究为提高影像解译的准确性,在对2002年2月9日覆盖元江全景的TM卫星影像进行数据校正、影像融合、影像分层、计算机自动监督分类的基础上,利用全球卫星定位系统(GPS),结合野外踏察及地形图、土地利用相关信息对机读结果进行目视检验和GIS分析校正,最终划分出18类植被类型、9类土地利用类型。判读结果经检验,土地利用的判读精度为84.2%,植被类型的判读精度为80.6%。  相似文献   

14.
以准格尔丘陵沟壑区五分地沟流域为研究区,应用彩红外航片和IKONOS卫星影像,绘制了1987、2002年土地覆盖/植被类型图,并数字化基于地面土地利用调查绘制的1979年土地利用图.利用景观格局指数,评价了研究区土地覆盖/植被空间格局现状及土地覆盖类型动态变化;并以ETM 数据为信息源,绘制了2002年土地覆盖/植被类型图.研究表明:2002年研究区土地覆盖/植被呈现出一个耕地、草地、人工乔木林和人工灌木林以及种植稀疏灌木的草地高度镶嵌的景观格局特征;20年内土地覆盖类型发生了显著的变化,景观异质性增强.基于研究区景观的高度破碎化,绘制小流域精细尺度土地覆盖图,高空间分辨率遥感数据十分必要.  相似文献   

15.
准格尔丘陵沟壑区五分地沟流域土地覆盖分析   总被引:1,自引:0,他引:1  
以准格尔丘陵沟壑区五分地沟流域为研究区,应用彩红外航片和IKONOS卫星影像,绘制了1987、2002年土地覆盖/植被类型图,并数字化基于地面土地利用调查绘制的1979年土地利用图.利用景观格局指数,评价了研究区土地覆盖/植被空间格局现状及土地覆盖类型动态变化;并以ETM 数据为信息源,绘制了2002年土地覆盖/植被类型图.研究表明:2002年研究区土地覆盖/植被呈现出一个耕地、草地、人工乔木林和人工灌木林以及种植稀疏灌木的草地高度镶嵌的景观格局特征;20年内土地覆盖类型发生了显著的变化,景观异质性增强.基于研究区景观的高度破碎化,绘制小流域精细尺度土地覆盖图,高空间分辨率遥感数据十分必要.  相似文献   

16.
We review literature on high voltage transmission lines and their effect on wild reindeer ( Rangifer tarandus ) migration patterns and area use. We conclude that reliable knowledge is lacking on the effects of transmission lines on reindeer ecology. This condition relates to the lack of long-term monitoring of reindeer migration patterns in relation to existing lines. It is also related to the fact that nothing is known about hearing in reindeer (or any other deer species in Norway) in relation to transmission line noise, which is considered an obstacle for migrating reindeer.
We then outline a research programme that includes a laboratory study to determine the audiogram in reindeer and two field studies to examine the proximate effects of transmission lines - independently as well as combined with ambient environmental variables - on reindeer behaviour. The audiogram in two yearling male reindeer has been determined; this part of the study will be completed this year with the determination of a corresponding audiogram in two female yearlings. The behaviour study of domestic reindeer under high voltage transmission lines was completed in September 1999. The behaviour study of wild reindeer in the area crossed by a 420 kV power line will continue this year and its completion is anticipated in 2001.  相似文献   

17.
基于多期数据集的中亚五国土地利用/覆盖变化分析   总被引:4,自引:0,他引:4  
针对目前中亚地区土地利用变化和分布格局方面的信息相对匮乏,现有资料较为陈旧且零散,无法满足中亚生态与环境变化研究需求的现状,利用全球的UMD, DISCover,GLC2000,GlobCover2005和GlobCover2009的5期土地覆被遥感数据集,提取中亚地区长时间序列土地覆被信息。并针对上述4个土地覆被分类系统无法进行直接对比和变化分析的问题,分别将其综合为4类土地覆被类型:耕地、自然植被、水体和其他,以分析近30 a中亚土地利用/土地覆被变化趋势。中亚土地利用类型多样,草地、裸地、农田、灌丛占绝对优势。自前苏联解体以后,20世纪90年代初至2000年期间,耕地面积大幅度减少,至2010年尽管有所恢复,但仍无法达到20世纪90年代初水平。而自然植被表现出了相反的趋势,这说明在此时间段内,由于社会政治制度的变化和市场经济的建立,耕地发生了较大规模的弃耕,弃耕地通常转换为草地、灌丛等自然植被。近10 a由于社会经济条件的变化,前苏联解体后所弃耕的土地又被收复和重新开发为耕地。90年代初至2000年期间,水体呈现先减少后增加的趋势。利用全球基于多期不同信息源获得的中亚土地覆被数据,尽管分类体系不统一,但均可较好地表征当时地表覆被状况。这在一定程度上弥补了中亚地区土地覆被数据不足的现状。通过对耕地、自然植被、水体及其他土地覆被类型进行大类合并,可基本体现中亚土地覆被的宏观特征和变化趋势。  相似文献   

18.
毛乌素沙地沙漠化的遥感监测   总被引:29,自引:13,他引:29  
吴薇  王熙章 《中国沙漠》1997,17(4):415-420
通过对1987年和1993年TM数据的分析和计算机辅助系统的应用,开展了毛乌素沙地沙漠化土地的动态监测。结果表明,在这7a间,研究区内沙漠化土地面积共减少了1936km2,总体上处于稳定的逆转状态,但局部地带沙漠化迅速蔓延不可忽视;几乎所有的逆转面积都来自于被固定和半固定后的流动沙丘(地)面积的减少,可见“三北”防护林建设及沙地围封保护的积极效果;但作为农牧业用地的不同程度沙漠化土地逆转不明显,势必会影响到防治的经济效益。研究还表明,遥感与计算机相结合对沙漠化土地的监测评价是一种行之有效的定量研究方法  相似文献   

19.
Centuries of seasonal farming in the Norwegian mountains led to a decrease in forested areas, a lowering of the alpine tree- and forest lines, and an increase in grassland coverage in the subalpine zone. Since the mid-19th century seasonal farming has declined significantly. In the sub-alpine belt, this has resulted in woodland succession on former hay meadows and open grasslands and heathlands. In contrast, vegetation changes caused by seasonal farming and its decline in alpine environments may be comparatively subtle because of unsuitable conditions for tree growth. The study examines vegetation changes in a former mountain summer farming area in the alpine zone of Western Norway using data on present and previous vegetation and old photographs. On curtilages high levels of defoliation, trampling and nutrient accumulation resulted in grass- and herb-dominated vegetation that differs significantly from that of surrounding areas. This curtilage-specific vegetation is persistent and occurs even at locations that have been grazed with only low intensity for several decades. Local concentrations of nutrients are probably a key factor that maintains the grass-dominated vegetation and strongly delays or even prevents regrowth of shrub heath.  相似文献   

20.
The open coastal heathlands in Norway have changed character in recent decades, mainly because traditional practices such as burning, cutting and grazing have been abandoned or reduced. In a project aimed at increasing our knowledge of woodland regeneration in oceanic boreal heathlands, an area on the island of Kalv?ya in the archipelago of Vikna on the extreme outer coast of central Norway has been studied. Kalv?ya has calcareous bedrock; rich heath, rich fens and low-herb woodland cover 20% of the island. Large parts are paludified, and wet heath and mire vegetation cover 60%. The island has not been inhabited, but it was used for summer farming in the latter part of the 19th century and later for stock grazing. The woodland and scrub were mapped using aerial photographs from 1961 and 1981, and by fieldwork in 2001. Vegetation changes were analyzed using GIS techniques. Woodland and scrub increased from 3.0% in 1961, to 4.3% in 1981, to 11.6% in 2001. Betula pubescens is the commonest woody species. The oldest trees are 150 to 175 years old, growing in the most heavily wooded area, far away from the summer farm. In addition to human impact (summer farm, grazing pressure), the geology, terrain (degree of exposure), and climatic factors are important for woodland colonisation and distribution.  相似文献   

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