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1.
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Summary The method of mapping the vegetation on scale 1: 200,000 and the starting points in relation to the potential natural vegetation and ecotopes, are discussed.In view of the planological background of this study, some restrictions have been added to the concept of potential natural vegetation, concerning the period of development and the human influence.The relationship between soil, ground water and vegetation was studied, which resulted in the map of the potential natural vegetation.Each type of potential natural vegetation stands for a series of vegetation types on the same site. Seven main series, with a number of sub-series are distinguished. Within each vegetation series the plant communities have been spread over five groups, according to their structure and naturalness.Ecotopes and ecotope complexes are considered as landscape ecological units. A list of ecotopes was obtained by interpreting topographical maps and by inventory data.The actual vegetation was mapped by estimating the size of the ecotopes within the separate areas. It was expressed in a five figure code for the five groups from the vegetation and ecotopes is combined into the vegetation map of The Netherlands.Interpretation problems, some of them specific for The Netherlands, are discussed and some remarks are made on the necessity of further research.Contribution to the Symposium on Plant Species and Plant Communities, held at Nijmegen, 11–12 November 1976, on the occasion of the 60th birthday of Professor Victor Westhoff.Nomenclature follows Heukels-van Ooststroom, Flora van Nederland, 18e druk, 1975, Wolters-Noordhoff, Groningen; nomenclature of syntaxa follows Westhoff & den Held (1969)  相似文献   

3.
Question: Coastal dune systems are characterized by a natural mosaic that promotes species diversity. This heterogeneity often represents a severe problem for traditional mapping or ground survey techniques. The work presented here proposes to apply a very detailed CORINE land cover map as baseline information for plant community sampling and analysis in a coastal dune landscape. Location: Molise coast, Central Italy. Method: We analysed through an error matrix the coherence between land cover classes and vegetation types identified through a field survey. The CORINE land cover map (scale 1: 5000) of the Molise coast was used with the CORINE legend expanded to a fourth level of detail for natural and semi‐natural areas. Vegetation data were collected following a random stratified sampling design using the CORINE land cover classes as strata. An error matrix was used to compare, on a category‐by‐category basis, the relationship between vegetation types (obtained by cluster analyses of sampling plots) and land cover classes of the same area. Results: The coincidence between both classification approaches is quite good. Only one land cover class shows a very weak agreement with its corresponding vegetation type; this result was interpreted as being related to human disturbance. Conclusions: Since it is based on a standard land cover classification, the proposal has a potential for application to most European coastal systems. This method could represent a first step in the environmental planning of coastal systems.  相似文献   

4.
Question: Is there a need for disturbance mapping integrated in the CircumBoreal Vegetation Mapping Program? Location: Eurasian boreal forest. Disturbance and mapping: The boreal zone is characterized by a multitude of natural and anthropogenic disturbance agents with importance over a wide range of spatial and temporal scales. Disturbance is a prime driver of succession in most of the boreal zone, producing landscape diversity characterized by a large‐scale vegetation mosaic of early to late succession states. When mapping the circumboreal vegetation, spatial extent, time involved from disturbance to recovered condition and likelihood of interacting disturbance types are crucial for how current vegetation is interpreted and subsequently included as map characteristics. In this paper we present examples from the boreal zone where natural and/or anthropogenic disturbance regimes dominate the state and distribution of vegetation, and possibilities for assessing the nature and extent of the disturbed regions using remotely sensed data. Conclusion: Disturbed vegetation occupies large areas in the boreal zone and related vegetation successions should be adequately represented when mapping the zone. In regions where the ‘potential natural vegetation’ is a hypothetical reconstruction from remnants of ‘natural’ vegetation it would be preferable to use the concept of ‘actual real vegetation’ for which remote sensing at coarse, medium and fine resolution is an efficient tool. The Land Cover Classification System (LCCS) may offer sufficient flexibility to incorporate information about the disturbance of circumboreal vegetation.  相似文献   

5.
Abstract. In this study we report the first application of Landsat TM imagery to Chaco vegetation studies at a regional scale in Argentina. We produced a map showing 13 clearly differentiated land‐cover types, and described the composition and structure of the plant communities, in an area of almost 42002 km2 in central Argentina. The land‐cover map obtained shows that the Chaco vegetation in central Argentina is highly disturbed. In the lowland part of the area the dominant land‐cover types are largely cultural landscapes and substitute shrublands, which have displaced the original Chaco forests, leaving only small isolated remnants generally confined to sites with some kind of constrain for agriculture. The use of TM images and the multivariate analysis of phytosociological data showed a qualified, high accuracy mapping capability for land‐cover types in the Chaco region (ca. 85% overall accuracy). Our results highlight the utility of TM and field data in a subtropical to warm‐temperate region, which is promising where other ancillary data are not available and a rapid acquisition of reliable vegetation data is required, so constituting a starting point for an imperative and more extensive classification and mapping of the endangered Chaco region.  相似文献   

6.
Lewis  Megan M. 《Plant Ecology》1998,136(2):133-133
This study demonstrates a vegetation mapping methodology that relates the reflectance information contained in multispectral imagery to traditionally accepted ecological classifications. Key elements of the approach used are (a) the use of cover rather than density or presence/absence to quantify the vegetation, (b) the inclusion of physical components as well as vegetation cover to describe and classify field sites, (c) development of an objective land cover classification from this quantitative data, (d) use of the field sample sites as training areas for the spectral classification, and (e) the use of a discriminant function to effectively tie the two classifications together. Land cover over 39000 ha of Australian chenopod shrubland was classified into nine groups using agglomerative hierarchical clustering, a discriminant function developed to relate cover and spectral classes, and the vegetation mapped using a maximum likelihood classification of multi-date Landsat TM imagery. The accuracy of the mapping was assessed with an independent set of field samples and by comparison with a map of land systems previously interpreted from aerial photography. Overall agreement between the digital classification and the land system map was good. The units that have been mapped are those derived from numeric vegetation classification, demonstrating that accepted ecological methods and sound image analysis can be successfully combined.  相似文献   

7.
G. Londo 《Plant Ecology》1974,29(1):51-61
Summary The succession of the dune slack vegetation around an artificial lake was studied by means of successive mapping. A succession scheme was prepared on the basis of comparison of the maps made in various years. This scheme was discussed in terms of systems theory, with reference to a kinematic graph prepared on the basis of the transformations. The succession derived from the vegetation maps was compared with that derived from the permanent plots; the results of this comparison indicated that only a small proportion of the total number of succession lines could be detected with the aid of the permanent plots. In addition, the information that could be derived from the permanent plot analysis depended on the degree of change of the vegetation in the area; more information could be derived from drier areas which showed the least degree of change. The best method for the investigation of the succession proved to be a combination of a restricted number of permanent plots and successive mapping. Nomenclature of species follows Heukels-van Ooststroom Flora van Nederland, 16 ed. 1970. R.I.N.-Comm. nr. 107.  相似文献   

8.
Abstract. Due to the complexity of coastal barrier vegetation, it is useful to apply a functional-type approach to assess the response of barrier island vegetation to climate change. In this paper, a simple clustering analysis is applied to a group of 19 plant associations, based on six plant attributes and six environmental constraints. This analysis results in the suggestion that the main division of the vegetation types at Virginia Coast Reserve is between herbaceous and woody types, which differs from the existing classification which recognizes three groups: xeric-mesic herbaceous, woody and hydric-halophytic herbaceous. Considerations about grouping plant functional types are also addressed in this paper. At a global scale, inclusion of barrier plant functional types may not be so important for the climate-change response of vegetation, but it may be necessary to consider these important systems for spatially explicit modelling of landscape responses.  相似文献   

9.
J. S. Beard 《Plant Ecology》1975,30(3):179-187
Summary The aims and methods of the Survey in providing vegetation map coverage for the State of Western Australia on scales of 1 : 1 000 000 and 1 : 250 000 are described. The theoretical basis of the classification of vegetation units is described and a mapping notation which was evolved to characterise precisely the units mapped. It is shown that the mapping serves to define precise boundaries for phytogeographical units (botanical districts and provinces) and has contributed to a study of palaeodrainage patterns in the arid interior.
Zusammenfassung Ziel und Methoden der Vegetationskartierung des Staates Western Australia in den Ma?st?ben 1 : 1.000.000 und 1 : 250.000 werden beschrieben, sowie die theoretische Grundlage der Klassifikation der Vegetationseinheiten und die zur genauen Charakterisierung der kartierten Einheiten entwickelten Kartierungsbezeichung. Es wird gezeigt da? die Kartierung dazu dienen kann die genauen Grenzen von pflanzengeographischen Einheiten (botanische Distrikte und Provinzen) festzustellen. Weiterhin hat die Kartierung zu einer Untersuchung der ‘Pal?o-Entw?sserung’-Systeme beigetragen.
  相似文献   

10.
Aim The aim of this study is to introduce a structural vegetation map of the Serengeti ecosystem and, based on the map, to test the relative influences of landscape factors on the spatial heterogeneity of vegetation in the ecosystem. Location This study was conducted in the Serengeti–Maasai Mara ecosystem in northern Tanzania and southern Kenya, between 34° and 36° E longitude, and 1° and 2° S latitude. Methods The vegetation map was produced from satellite imagery using data from over 800 ground‐truthing points. Spatial characteristics of the vegetation were analysed in the resulting map using the fragstats software package. Average patch area and nearest neighbour distance (NND) were determined for grassland, shrubland and woodland vegetation types. The heterogeneity of vegetation types was estimated with Simpson’s diversity index (D). Structural equation modelling (SEM) was used to explore the relationships between the spatial characteristics of vegetation and three predictor variables: annual rainfall, coefficient of variation (CV) in annual rainfall, and topographic moisture index (TMI). Results A vegetation map is presented along with a detailed summary of the distribution of land‐cover classes and spatial heterogeneity in the ecosystem. Significant relationships were found between vegetation diversity (D) and TMI, and also between D and average rainfall. The average area of grassland patches showed significant relationships with average rainfall, with rainfall CV and with TMI. Grassland NND was positively associated with average rainfall. Woodland patch area showed a unimodal response to average rainfall and a negative linear association with TMI. Woodland NND showed a U‐shaped association with annual rainfall and a weaker positive linear association with TMI. An acceptable model that explained variation in shrubland patch characteristics could not be identified. Main conclusions The vegetation map and analysis thereof resulted in three significant causal explanatory models that demonstrate that both rainfall and topography are important contributors to the distribution of woodlands and grasslands in the Serengeti. These findings further indicate that changes in patch characteristics have a complex interaction with rainfall and with topography. Our results are concordant with recent studies suggesting that percent woody cover in African savannas receiving less than c. 650 mm year?1 is bounded by average annual rainfall.  相似文献   

11.
植被志(vegegraphy)是基于植被调查资料, 全面记叙植被的群落外貌、种类组成、结构和功能、生境条件, 以及地理分布等特征, 并对同类植被进行归纳和总结的志书。“植被志”的英文译为“vegegraphy”, 是本文的新造词, 它是由“vegetation”的词头“vege-”和英文后缀“-graphy” (记叙之意)组成的合成词。《中国植被志》的研编是一项时间紧迫、内容复杂、工作量浩繁的重大科学工程。它的完成将极大提升中国植被科学和生态学的研究水平, 并为中国植被资源的合理利用、生物多样性保护及生态环境治理等提供不可或缺的基础资料。本文首先简述了植被的基本特征(主要包括外貌特征、种类组成、群落结构以及动态变化等)和国内外植被调查的进展情况, 简要回顾了中国植被分类系统的研究历史, 并对以往的分类系统进行了若干修订。在此基础上, 着重讨论并提出了《中国植被志》卷册编排体系和用于《中国植被志》研编的植被类型划分方案。在对植被分类系统的修订方面, 主要对高级分类单位及相对应的英文名称进行了讨论和修订。按照本文修订的分类系统, 中国植被的分类单位及其对应的英文名称分别是: 植被型组(Vegetation Formation Group)、植被型(Vegetation Formation)和植被亚型(Vegetation Subformation)、群系组(Alliance Group)、群系(Alliance)和亚群系(Suballiance)、群丛组(Association Group)以及群丛(Association)。在植被型组中, 划分为9类: 森林、灌丛、草本植被、荒漠、高山冻原与稀疏植被、沼泽与水生植被、农业植被、城市植被及无植被地段。关于《中国植被志》的卷册编排和“植被类型”划分, 首先按高级分类单位——植被型划分相应的“卷”; 在此框架下, 模糊“植被亚型”、“群系组”和“群系”的概念, 确定“植被类型” (Vegetation type), 并将其作为植被志各卷中的“册”。这样处理不仅保证了研编工作的可操作性, 也保持了同一卷册中特定植被类型的完整性。《中国植被志》编排体系中的“植被类型”的划分很重要, 它是指具有相同建群种及相同优势类群(如种、属)的植被组合, 但它不是严格意义上的植被分类单位。“植被类型”的划分遵循“优势类群及生活型的同一性, 生境条件的相对重要性, 植被特征及用途的差异性, 以及突出植被志的应用性”等原则。按该编排体系, 《中国植被志》将由48卷约110册组成。  相似文献   

12.
Aims Mapping vegetation through remotely sensed images involves various considerations, processes and techniques. Increasing availability of remotely sensed images due to the rapid advancement of remote sensing technology expands the horizon of our choices of imagery sources. Various sources of imagery are known for their differences in spectral, spatial, radioactive and temporal characteristics and thus are suitable for different purposes of vegetation mapping. Generally, it needs to develop a vegetation classification at first for classifying and mapping vegetation cover from remote sensed images either at a community level or species level. Then, correlations of the vegetation types (communities or species) within this classification system with discernible spectral characteristics of remote sensed imagery have to be identified. These spectral classes of the imagery are finally translated into the vegetation types in the image interpretation process, which is also called image processing. This paper presents an overview of how to use remote sensing imagery to classify and map vegetation cover.Methods Specifically, this paper focuses on the comparisons of popular remote sensing sensors, commonly adopted image processing methods and prevailing classification accuracy assessments.Important findings The basic concepts, available imagery sources and classification techniques of remote sensing imagery related to vegetation mapping were introduced, analyzed and compared. The advantages and limitations of using remote sensing imagery for vegetation cover mapping were provided to iterate the importance of thorough understanding of the related concepts and careful design of the technical procedures, which can be utilized to study vegetation cover from remote sensed images.  相似文献   

13.
Küchler  A. W. 《Plant Ecology》1984,55(1):3-10
On ecological vegetation maps, the distribution of vegetation is related to one or more features of the environment. Tolerance, competition, map scales and the environment are discussed with regard to their bearing on the geographical distribution of phytocenoses and their portrayal on maps. There are two types of ecological vegetation maps: those relating the vegetation to one environmental quality, and those with two or more such qualities. The interpretation of ecological vegetation maps is relatively simple when plant communities are related to a single quality of the biotope and difficult but usually more useful when related to several qualities. Perfection is not possible but can be approached asymptotically.  相似文献   

14.
When vegetation trends over time are analysed from an appropriate long‐term perspective using palaeoecological records, the concept of potential natural vegetation (PNV) is unsupported because of continual vegetation changes driven by natural or anthropic forcings. However, some palaeoecological records show long‐lasting (i.e. millennial) vegetation stability at multidecadal to centennial time scales in the absence of natural and human drivers of change, which fits within the definition of PNV. A more detailed palaeoecological analysis of these records shows that they are an exception rather than a rule, and that they cannot be differentiated from other transient ecological states. Therefore, long records of vegetation stability cannot be considered to be valid evidence for PNV. From a palaeoecological perspective, the PNV concept is concluded to be unnecessary, even in cases of multidecadal to centennial vegetation stability in the absence of environmental disturbance.  相似文献   

15.
ABSTRACT

The aim of this paper is to present a joint vegetation data base and GIS application to produce a model to map the potential natural vegetation (PNV) of the Friuli-Venezia Giulia region (NE Italy) and to show how the map can be used to draw a biogeographic classification of the region. All the natural arboreal coenoses growing below the timber line, as well as the dwarf shrubs and prairies developing above this limit, were considered. Some cross sections, extracted from the potential vegetation map, were tested against transects of real vegetation distribution.  相似文献   

16.
In order to emphasize the importance of vegetation mapping for nature conservation purposes a case study in Terceira island (Azores) is presented, in which the importance of the natural vegetation of the eastern slope of Santa Bárbara volcano (which is part of the Site of Community Importance of Santa Bárbara–Pico Alto) is evaluated through the elaboration of its vegetation map. Fourteen (14) different natural vegetation types were identified: grasslands (1 type), peat bogs (2 types), scrubs (2), forests (5), successional vegetation (3) and vegetation of rocky slopes (1). All communities are protected under the Habitat and Species Directive (EC/92/43) and most of them are endemic to the Azores Islands. This fact, together with the significant number of Azorean endemic taxa (18), Macaronesian endemic taxa (5) and species protected under the Habitat and Species Directive (7), gives this area an important conservation value that justifies future protection actions. Vegetation mapping is an important tool for the characterization, evaluation and implementation of managing plans of natural areas of the Azores islands. The use of a floristic-based classification, supported by multivariate analysis and structural data, is an efficient methodology for the construction of these maps. The data collected comprise an important set of information about the distribution and abundance of natural vegetation types and endemic and rare species. This information was not available until now and is indispensable for the elaboration of management plans of Special Zones for Conservation that will be part of the NATURA 2000 network.  相似文献   

17.
18.
Westfall  R. H.  Theron  G. K.  Rooyen  N. 《Plant Ecology》1997,132(2):137-154
A program package is described in which vegetation data can be objectively classified and analysed. Classification is based on minimum entropy. Results show that in a comparison with TWINSPAN, improvements to the relevé sequence, in terms of community variation, can be obtained. Furthermore, TWINSPAN classifications are shown to be dependent on a particular relevé input sequence.  相似文献   

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对中国植被分类系统的认知和建议   总被引:1,自引:0,他引:1       下载免费PDF全文
《中国植被志》的编写工作已经启动, 藉此征求修订《中国植被分类系统》意见之际, 提出几点看法与建议: 1)贯彻原先制定的中国植被“高级分类单位偏重于生态外貌, 而中、低级分类单位则着重种类组成和群落结构”的分类原则。这一思想与当前国际上植被分类的发展是一致的。2)中国植被分类既要符合中国植被的特点, 又要适应全球植被分类的发展, 名词概念应尽量与国际上的广泛理解相一致。3) “群丛”是《中国植被志》描述的基本对象, 其概念需要统一, 以避免歧义和可能导致的南北“群丛”的不等质。资料不足的类型应组织野外补点调查。4)植被分类等级系统是严格的, 但各等级又是开放的, 可适当地增设高级分类单位, 以适应类型扩展之需要。该文附有从植被型纲到植被型的建议草案。  相似文献   

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