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1.
Landscape is defined as the material-physical entity comprising the structures of nature and land use and their mutual relationship. This reduced but more precise specification of the landscape includes certain geo- and bioscientific problems as well as socio-economic conditions, motives and functions in the sense of a system approach, which have to be considered, but to do not belong to its object sphere directly. For landscape research a multi-stage procedure is introduced. It includes (a) the scientific and technical analysis of natural and land use structures inclusive their spatial and temporal dynamics (and genesis), (b) the functional analysis of landscape within the processes of socio-economic reproduction, i.e. landscape as an object of socio-economic activities and (c) the comparison of landscape structures with standardized parameters set by society under consideration of natural regularities leading to the evaluation and prognosis of these structures or certain parts of them.  相似文献   

2.
In landscape diagnosis landscapes are evaluated on the basis of their natural and technological characteristics with regard to the possibilities and risks of intensive utilization. Land use is an essential criterion for the evaluation of the condition of landscapes. Remote sensing will allow for an analysis of large areas with regard to land use. Landscape diagnosis through satellite photographs will be illustrated in two examples. In the first one multitemporal evaluation of satellite photographs is discussed with particular reference to attempts made to characterize the utilization of landscape potentials. In the second example attempts have been made to classify medium-sized landscape units by satellite photographs, with additional characterization through thematic maps based on the Atlas GDR.  相似文献   

3.
Lanthanoids were studied in a boreal landscape where an abundance of acid sulfate soils and Histosols provide a unique opportunity to increase the understanding of how these metals behave in acidic soils and waters and interact with soil and aqueous organic matter. In the acid sulfate soils lanthanoids are mobile as reflected in high to very high concentrations in soil water and runoff (typically a few mg l−1 but up to 12 mg l−1) and abundant release by several relatively weak extractants (ammonium acetate EDTA, sodium pyrophosphate, hydroxylamine hydrochloride) applied on bulk soil. Normalisation with the lanthanoid pool in the underlying parent materials (sulphide-bearing sediments deposited in brackish-water) and soil water showed that the extensive release/retention in the acidic soil was accompanied by large, and variable, fractionation trends across the lanthanoid series. In low-order streams draining these soils, the lanthanoid concentrations were high and, as indicated by frontal ultrafiltration and geochemical modelling, largely dissolved (<1 kDa) in the form of the species LnSO4+ and Ln3+. In other moderately acidic stream waters (pH 4.3-4.6), organic complexation was predicted to be important in the <1 kDa fraction (especially for the heavy lanthanoids) and strongly dominating in the colloidal phase (1 kDa-0.45 μm). Along the main stem of a stream in focus (catchment area of 223 km2), lanthanoid concentrations increased downstream, in particular during high flows, caused by a downstream increase in the proportion of acid sulfate soils which are extensively flushed during wet periods. The geochemical models applied to the colloidal Ln-organic phase were not successful in predicting the measured fractionation patterns.  相似文献   

4.
Re-evaluation of the river history, palaeosurface levels and exhumation history in northern Switzerland for the last 10 million years reveals that distinct morphotectonic events about 4.2 and 2.8 million years ago (Ma) caused major reorganisation of river networks and morphosculpture. As a result of the earlier formation of the Swiss Jura, potential relief energy in the piggy-back North Alpine Foreland Basin (NAFB) of northern central Switzerland south of the Jura fold belt was built up after 11–10 Ma. It was suddenly released by river capture at about 4.2 Ma when the Aare-Danube was captured by a tributary of the Rhône-Doubs river system which rooted southeast of the Black forest. This event triggered rapid denudation of weakly consolidated Molasse sediments, in the order of about 1 km, as constrained by apatite fission track data from drillholes in the NAFB. Likely mechanisms of river capture are (a) headward erosion of Rhône-Doubs tributaries, (b) uplift and rapidly increasing erosion of the Swiss Alps after about 5.3 Ma, and (c) gravel aggradation at the eastern termination of the Jura fold belt in the course of eastward and northward tilt of the piggy-back NAFB. A morphotectonic event between 4.2 and 2.5 Ma, probably at about 2.8 Ma, caused a phase of planation, accompanied by local gravel aggradation and temporary storage of Alpine debris. Between 2.8 and 2.5 Ma, the Aare-Rhône river system is cannibalised by the modern Rhine River, the latter later connecting with the Alpine Rhine River.  相似文献   

5.
An increasing number of the people responsible for promoting tourism understand the necessity of landscape conservation and sustainable development. Sustainability and the maintenance of regional identity depend on the kind of tourism that takes account of the landscape and stops short of a blind modification of it, for instance through the installation of inappropriate large-scale tourist infrastructure. Since the 1970s South Tyrol, Italy’s most northern province (Autonome Provinz Bozen/Südtirol; Provincia Autonoma di Bolzano/Alto Adige), has engaged in tourism of outstanding quality, centreed on the existing landscape potential. Until today this has been the basis for successful tourism development. In the meantime however, there have been calls in South Tyrol for a quantitative expansion, founded on the implementation of an artificial touristic infrastructure and products. As is the case in many other alpine regions, this could be detrimental to the quality of the landscape. Supported by tourism research and based on the authors’ own long-standing experience, this article analyzes the development and trends of tourism in South Tyrol from a geographical perspective and takes a critical look at the various planning prospects and the problems which might evolve for the landscape and for tourism marketing.  相似文献   

6.
Central Queensland lies on the passive margin of eastern Australia and owes its landscape to processes that began following rifting and opening of the Tasman Sea. The modern landscape is the result of long-term processes of landform development, and the landforms themselves are the evidence of these processes. Hence, interpreting their significance provides an understanding of long-term landscape evolution. Along the eastern Australian coast, numerous rivers drain into the sea but among these, there are two that stand out: the neighbouring Fitzroy and Burdekin Rivers in central Queensland. These two streams have by far the largest catchments of any rivers along the eastern seaboard of Australia. The Burdekin and Fitzroy catchments contain widespread remnants of Cenozoic deposits, which accumulated predominantly in fluvial and lacustrine environments established during the Palaeogene. Alluvial sediments were supplied by erosion of nearby uplands, and accumulated in depressions and basins on a prior land surface. Volcanic activity also resulted in large lava flows in central western areas. Water was the main agent of sediment transport, distributing unconsolidated deposits along the drainage networks of the time, some of which were directed inland. It is inferred that during the Palaeogene, the divide between coastward and inland draining streams was further to the east than it is at present. Several basins were located west of the former coastal divide, and were characterised by continental environments of deposition in a generally westward drainage system. With continued accumulation of sediments, individual basins overflowed and merged to form a widespread flat-lying Palaeogene landscape that concealed an earlier land surface on which bedrock was more extensive. In the Early Cenozoic, there was a change from the depositional phase that resulted in the continental sequence, to an erosional phase that developed the modern landforms. The change from deposition to erosion probably started during the Palaeogene. Erosion continued through to the present, re-exposing parts of the basal Palaeogene sequence and earlier Mesozoic land surface. The erosional phase that shaped the landforms of the modern Burdekin and Fitzroy catchments can be explained by slowly evolving drainage basins in the interior being captured by small coastal streams—the predecessors of the Burdekin and Fitzroy Rivers. The coastal streams were short and steep in comparison with those in the interior, allowing a more active erosional environment along the coast. As the coastal streams expanded, the drainage divide moved rapidly westwards. Stream capture began a phase of regional erosion, which transported large quantities of sediments to the coast. The sediments contributed to coastal and nearshore features similar to the Holocene high sea-level examples at the mouth of the Burdekin River in the north, and the Fitzroy Delta and the Keppel Coast in the south. Large volumes of sediments were also transported beyond the present coast during low sea-levels of the Cenozoic, forming similar coastal features and contributing to a major eastward bulge on the central Queensland continental shelf. The emptying of continental basins has paralleled the development of the continental shelf bulge from the coast to the Marion Plateau.  相似文献   

7.
The nature of the valley forms, and associated superficial deposits and soils of the South‐West Drainage Division of Western Australia are described. All the major rivers tap interior palaeo‐drainage lines associated with chains of salt lakes; thereafter, downstream, there is a succession of valley forms which are progressively more sharply incised and of steeper gradient. It is shown that this succession is repeated in all major rivers. The main palaeo‐drainage systems are named for the first time, and their catchments delineated. The changes in valley form which occur downstream of the palaeo‐drainage lines are interpreted as stages in rejuvenation of drainage of the epeiro‐genically uplifted Old Plateau of Western Australia. The relationship between the valley forms and patterns of distribution of soils, deeply weathered profiles and superficial deposits is described, and its agricultural, geochemical and hydrological significance briefly discussed.  相似文献   

8.
Recent accounts suggest that periglacial processes are unimportant for large-scale landscape evolution and that true large-scale periglacial landscapes are rare or non-existent. The lack of a large-scale topographical fingerprint due to periglacial processes may be considered of little relevance, as linear process-landscape development relationships rarely can be substantiated. Instead, periglacial landscapes may be classified in terms of specific landform associations. We propose “cryo-conditioning”, defined as the interaction of cryotic surface and subsurface thermal regimes and geomorphic processes, as an overarching concept linking landform and landscape evolution in cold regions. By focusing on the controls on processes, this concept circumvents scaling problems in interpreting long-term landscape evolution derived from short-term processes. It also contributes to an unambiguous conceptualization of periglacial geomorphology. We propose that the development of several key elements in the Norwegian geomorphic landscape can be explained in terms of cryo-conditioning.  相似文献   

9.
10.
The main features of climate and geology relevant to a discussion of the soils and landscapes of Western Australia are briefly reviewed. The pattern of drainage is described in terms of six drainage divisions, each with characteristic physiography and soils. In the interior, this involves a reconstruction of an ancient drainage system, based on the maps of the Atlas of Australian Soils. It is shown, on a continental scale, that the major divides are characterised not only by deep, chemically weathered, often lateritic profiles, but also by extensive sandy deposits derived from these preweathered materials.  相似文献   

11.
Phyto-geomorphic classification of the landscape   总被引:1,自引:0,他引:1  
The subdivision of landscape into phyto-geomorphic units forms a useful basis for land resource surveys and for providing a holistic approach to potential biological productivity. This paper explains the natural basis for such units, justifies their subdivision into a hierarchy and gives definitive criteria for each categoric level. The main levels are the land zone, land division, land province, land region, land system, land catena and land facet, of which the province, system and facet are the more important. Most bear some analogy with categories recognized in pedology and plant ecology. Vegetation varies in importance in relation to landforms in land unit definition both regionally and categorically, being most important in forested areas and for certain other land categories. Sample areas in the United Kingdom, Australia and Jordan illustrate complete hierarchies of land units for different climatic zones. A simple procedure based on critical path analysis and using remotely sensed imagery, maps and other data can give a landscape analysis suitable for planning at a variety of scales.  相似文献   

12.
Jaromir Demek 《Geoforum》1978,9(1):29-34
The main object of study of geography is the landscape sphere that includes the surface of our planet. The landscape sphere differs from the other geospheres by displaying unusual complexity and consists of structured sets of components which exhibit discernible relationships with one another and operate as a system. The functioning of the landscape sphere is conditioned by the interrelationships of components, as well as by the transfer of mass and energy from one part of the landscape sphere to another in the form of streams of mobile elements. The author is using the name geosystem for determination of this system of planetary dimensions. The landscape sphere may be further divided into subsystems exhibiting characteristic features which facilitate their identification and delimitation.Territorial differentiation of the landscape sphere, on the basis of the law of zonality, produces horizontal, latitudinal and vertical zones called by author geoms. These geoms may be further subdivided into geosystems of smaller dimensions called geochoras. The basic geochora is the landscape. In most landscapes the key elements in these geosystems are controlled by Man and so-called cultural landscapes are developed. The cultural landscapes are parts of the landscape sphere within which natural and socioeconomic geosystems co-exist. The author further distinguishes cultured, disturbed and devastated landscapes. The study of cultural landscape is amongst the most difficult fields of investigation, but such studies are of great significance in terms of predicting future environmental developments.  相似文献   

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15.
The paper illustrates how spatially explicit forecasting of residential development can be undertaken and how it can be made sensitive to policy instruments available to local and state governments. Predicted values in residential use based on a hedonic analysis of residential property prices is found to have a significant effect on the hazard of development in a survival model used to explain the likelihood that a farm or forest will be converted to residential use. Policy instruments are imbedded in both the hedonic model of residential property values and a hazard model of parcel conversion, so as to test how effective changes in policies can be at changing the pattern of land-use change. Some of the statistical and modeling obstacles that impede progress on this spatially explicit modeling are also discussed.  相似文献   

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18.
景观生态风险评价能够有效地对区域景观格局进行优化并为风险防范提供理论基础.文献计量学分析表明,国内岩溶景观生态风险评价研究主要从"研究对象"、"评价模型"、"评价方法"和"评价指标"4个方面分析;而钙华作为特殊的岩溶体,目前对它的生态风险评价几乎未开展.文章从岩溶景观生态风险评价入手,基于模糊数学综合评判法和层次分析法...  相似文献   

19.
The Uummannaq region is a mosaic of glacial landsystems, consistent with hypothesized landscape distribution resulting from variations in subglacial thermal regime. The region is dominated by selective linear erosion that has spatially and altitudinally partitioned the landscape. Low altitude areas are dominated by glacial scour and higher elevations are dominated by plateaux or mountain valley and cirque glaciers. The appearance and nature of each landscape type varies locally with altitude and latitude, as a function of bedrock geology and average glacial conditions. Selective linear erosion has been a primary control on landscape distribution throughout Uummannaq, leading to plateau formation and the growth of a coalescent fjord system in the Uummannaq region. This has allowed the development of the Uummannaq ice stream's (UIS) onset zone during glacial periods. Fjord development has been enhanced by a downstream change in geology to less‐resistant lithologies, increasing erosional efficiency and allowing a single glacial channel to develop, encouraging glacier convergence and the initiation of ice streaming. The landscape has been affected by several periods of regional uplift from 33 Ma to present, and has been subject to subsequent fluvial and glacial erosion. Uplift has removed surfaces from the impact of widespread warm‐based glaciation, leaving them as relict landsurfaces. The result of this is a regional altitude‐dependent continuum of glacial modification, with extreme differences in erosion between high and low elevation surfaces. This study indicates that processes of long‐term uplift, glacial erosion/protection and spatial variability in erosion intensity have produced a highly partitioned landscape.  相似文献   

20.
Changes of landscape structure in Estonia during the Soviet period   总被引:3,自引:0,他引:3  
Ülo Mander 《GeoJournal》1994,33(1):45-54
The development of land-use structure during the Soviet period (1940–1991) has been analyzed. The main trends in land-use dynamics have been a decrease in the percentage of agricultural land and an increase in the share of forests. The most important driving factors of such a shift have been the land reforms of 1940, 1949 (collectivization followed by deportations), and 1989; and urbanization and concentration of agricultural production. Changes in land-use structure on the county level reflect well the socio-economic and political changes in Estonian society. An especially significant decrease in agricultural lands took place during the first ten years of collectivization. In coastal areas it has been combined with state political activities. Natural conditions also play an important role, particularly in local changes of land-use structure. The concentration of agricultural production, which is greater in the eastern part of Estonia (Upper Estonia), has caused many environmental problems. Likewise, land amelioration is one of the reasons for environmental disturbances. It has shifted agricultural activities from former arable lands to marginal areas (natural grasslands, wetlands). That is one of the reasons for nutrient cycling disturbances in agricultural landscapes. Despite many disturbances, Estonia has a well- developed network of ecologically compensating areas consisting of nature protection areas, forests, wetlands, and coastal waters. It is important to maintain this ecological network during privatization.  相似文献   

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