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1.
由A.W.Küchler博士和I.S.Zonneveld博士合编的《植被制图》(Vegetation Mapping)一书由Kluwer学术出版社于1988年出版。该书是由H.Lieth主编的《植被科学手册》的第十卷,是目前最新的植被制图学专著。本书第一编者A.W.Küchler博士曾于1967年出版过一部同名的书。在这两部书相距的二十多年间,一方面由于遥感技术、自动制图以及地理信息系统的迅速发展,已将植被制图技术提高到了一个新的水平;另一方面由于植被是整个景观(生态系统)的重要组分和景观状况的重要指示者,人类所面临的资源与环境问题无疑都与植被科学密切相关,这也就大大促进了植被制图理论及方法的发展并使植被制图的应用向深度和广度发展。以上  相似文献   

2.
植被图是表示多种植被或植物群落的空间分布规律及其生态环境的地图,它是生物多样性保护、生态研究、自然资源管理和生态恢复的重要依据.目前,中国植被专题资源信息的本底数据《中华人民共和国植被图(1:1000000)》从开始绘制至今已将近40年,中国的植被分布格局已经发生了极大的变化,《中华人民共和国植被图(1:1000000)》已存在植被斑块的类别和边界与现实不符等问题,中国的植被分布本底数据亟待更新.如今卫星遥感技术的发展为实现大面积区域的植被制图提供了一种实用且经济的手段.本文综述了国家尺度植被图的制图方法和卫星遥感技术在植被分类制图上的进展,并以此为基础,探讨中国新一代1:50万植被图的遥感制图方法.新一代1:50万中国植被图的绘制通过众源采集结合专家鉴定的方式获取海量植被类型样本,基于多源遥感数据,以植被斑块为对象,采用深度学习的方式实现遥感植被分类,并基于自主构建的植被在线平台,借助于全国各地的植被生态学家的专业知识实现对制图结果的校订和更新.  相似文献   

3.
植被图通常采用不同的颜色并结合符号来区分不同的植被类型, 以期更加直观、清晰地将植被类型信息传达给读者。如何通过色彩和符号的合理搭配来区分不同的植被类型是植被制图中的关键步骤, 尤其是对于植被类型较丰富的区域, 植被图的色彩和符号设计更为复杂。植被图图例系统建立在植被分类系统之上, 近10余年来我国的植被分类系统得到了进一步的发展和完善, 因此, 非常有必要在最新的植被分类系统基础上, 提出一套植被制图色彩和符号设计方案, 用以指导当前的植被制图工作。该研究整理了地图学、植被图以及其他专题地图色彩和符号设计的要求, 提出了植被制图的色彩和符号设计原则。在最新的植被分类系统基础上, 采用颜色三属性(色调、明度、饱和度)及符号的基本视觉变量(形状、尺寸、方向、色彩、密度、亮度)的变化及其组合, 依据色彩和符号设计的系统性、科学性、象征性等原则, 对中国植被分类系统高级分类单位中的植被亚型, 进行了标准化配色和符号设计, 旨在为植被制图工作者及新一代1:50万植被图编研提供理论依据和参考, 提升植被制图的效率和质量。  相似文献   

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利用地理信息系统技术进行生态图的编制   总被引:2,自引:0,他引:2       下载免费PDF全文
植被与生态因子之间相互关系的研究是植被生态学研究的核心之一,而生态图则是这一研究的直观具体表现。虽然植被学家很早就有了生态制图的思想,但由于植被与生态因子之间关系的复杂性以及空间分析手断和技术的薄弱,生态制图的发展一直很缓慢。随着计算机及地理信息系统(GIS)技术的迅速发展,使得生态图的编制成为目前植被制图学的最新发展趋向。  相似文献   

5.
借《中国植被志》编研与新一代中国植被图制图工作开展的契机,本文对四川省植被研究历史进行了回顾,分析了近40年来四川植被变化的影响因素,结合近年来的野外补充调查和文献资料,参考《中国植被》《中国植被及其地理格局》以及近期国内发表的植被分类系统,新拟了四川省植被制图分类系统(植被型组、植被型、群系三级),并对未来四川省植被研究提出几点希望:(ⅰ)四川植被分类系统总体上应与全国分类系统保持一致,个别单位上可以体现区域性的特点;(ⅱ)采用新技术、新方法加强四川省资料贫乏类型、区域的植被补充调查;(ⅲ)尽早启动《四川植被》的修订以及新一代四川省植被图编研工作,并建立可更新的数据库,为以后四川植被图的定期更新奠定基础.  相似文献   

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云南古蚤雄性的记述及雌性的形态补充   总被引:1,自引:0,他引:1  
根据采自云南丽江玉龙雪山和大理苍山背纹鼩鼱(Sorex cylindricauda)等小兽体的蚤类标本,首次对云南古蚤Palaeopsylla yunnanensis Xie et Yang.1982的雄性进行了描述并对雌性的部分形态进行了补充。  相似文献   

7.
青藏高原植被调查与制图一直是青藏高原植被生态学研究的重要内容。历史上,我国多次开展青藏高原植被考察活动,在植被制图方面取得了一系列重要成果。本研究首先基于文献研读对青藏高原植被考察及其成果进行回顾,并对制图范围包括青藏高原的、使用比较广泛的植被图进行对比和分析;然后,基于第二次青藏高原综合科学考察获取的植被调查样点数据,与多幅植被图在数据一致性方面进行了对比。结果表明:(1)青藏高原植被调查的历史久远,但系统、科学的青藏高原植被调查开始于1949年新中国成立之后,期间获取了大量植被调查数据,出版了大量的专著和图志,《中华人民共和国植被图(1:4,000,000)》《中国草地资源图集(1:1,000,000)》和《中华人民共和国植被图(1:1,000,000)》是包含整个青藏高原、应用最为广泛的3幅植被图,《青藏高原现状植被图》是基于现阶段植被调查数据制作的青藏高原植被图。但是这4幅图在植被分类体系上存在较大差异,严重影响了图件之间的可比性。(2)对比发现, 4幅植被图之间均存在一定程度的不一致性。面积较大的植被型组,如森林和草本植被,在植被图之间的一致性较高;但面积相对较小的植被型组,...  相似文献   

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云冷杉林是玉龙雪山东坡保存最完整的森林植被,为了更好地了解其物种组成和群落结构等基本特征,中国科学院昆明植物研究所联合玉龙雪山省级自然保护区管护局,按照CTFS(Center for Tropical Forest Science)的样地建设标准,于2012–2014年在玉龙雪山省级自然保护区内建立了25 ha(500 m×500 m)的长期监测样地。本研究以样地内所有胸径(DBH)≥1 cm的木本植物(不含竹子)为研究对象,分析了该样地的区系成分、群落组成、垂直结构及径级结构。结果表明:样地内DBH≥1 cm的木本植物(不含竹子)独立个体数为47,751,分属26科41属62种,以温带分布尤其是北温带成分为主要区系特征。重要值≥1的物种有18个,贡献了90.24%的重要值。群落垂直结构可分为4层,川滇冷杉(Abies forrestii)、丽江云杉(Picea likiangensis)和帽斗栎(Quercus guajavifolia)为主林层优势种和建群种,径级分布为峰型或近倒"J"型,持续更新能力较好;吴茱萸五加(Gamblea ciliata var.evodiifolia)、篦齿槭(Acer pectinatum)和短梗稠李(Padus brachypoda)是主亚林层的优势种,在某些片段可形成落叶阔叶林的优势群落,径级分布出现明显断层,未来将出现衰退。西康花楸(Sorbus prattii)、桦叶荚蒾(Viburnum betulifolium)和云南杜鹃(Rhododendron yunnanense)是次林层的优势种;灌木层假小檗(Berberis fallax)是样地内个体数最多的物种,占总个体数的59.51%,其重要值最高,占总数的22.75%,径级分布呈"L"型。  相似文献   

9.
遥感和GIS支持下的城市植被制图及其特征分析   总被引:16,自引:0,他引:16       下载免费PDF全文
 以上海城市植被为研究对象,探索城市植被的分类理论和方法,提出一套适用于城市植被分类与制图的方法。根据城市植被信息获取的方式以及生态-外貌分类原则,建立了基于植物生活型的、可用图形表示的城市植被分类体系,分天然与半天然植被和人工植被两个大类,共有9个植被型和34个植被亚型。在遥感和地理信息系统(GIS)技术的支持下,建立研究区的城市植被信息数据库,并在此基础上对城市植被类型的特征以及与土地利用的关系进行分析比较,以期掌握城市植被类型的数量特征及其空间分布,同时按不同分类级别用计算机进行城市植被制图。城市植被  相似文献   

10.
云南药山自然保护区种子植物区系的垂直分布格局   总被引:1,自引:0,他引:1       下载免费PDF全文
通过野外植被调查,结合文献资料,探讨了云南药山自然保护区种子植物区系的垂直分布格局.结果表明,温带区系成分所占比重,随着海拔的升高,总体上呈单调递增趋势,而热带区系成分所占比重呈单调递减格局;区系平衡点出现在海拔2000 m 左右.在平衡点之下,植物区系以热带、亚热带区系成分为主,而在此之上,则以温带区系成分为主.区系成分的聚类分析表明,研究区域内植被垂直带谱主要由1500 m以下的干热河谷植被、1500~2000 m左右的云南松林、2000~2600 m的常绿阔叶林、2600~3100 m的硬叶常绿阔叶林、3100~3600 m的亚高山灌丛和3600 m以上的高寒草甸构成,这与传统的植被类型划分方法的结果基本一致.  相似文献   

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Because the basic unit of biology is the cell, biological knowledge is rooted in the epistemology of the cell, and because life is the salient characteristic of the cell, its epistemology must be centered on its livingness, not its constituent components. The organization and regulation of these components in the pursuit of life constitute the fundamental nature of the cell. Thus, regulation sits at the heart of biological knowledge of the cell and the extraordinary complexity of this regulation conditions the kind of knowledge that can be obtained, in particular, the representation and intelligibility of that knowledge. This paper is essentially split into two parts. The first part discusses the inadequacy of everyday intelligibility and intuition in science and the consequent need for scientific theories to be expressed mathematically without appeal to commonsense categories of understanding, such as causality. Having set the backdrop, the second part addresses biological knowledge. It briefly reviews modern scientific epistemology from a general perspective and then turns to the epistemology of the cell. In analogy with a multi-faceted factory, the cell utilizes a highly parallel distributed control system to maintain its organization and regulate its dynamical operation in the face of both internal and external changes. Hence, scientific knowledge is constituted by the mathematics of stochastic dynamical systems, which model the overall relational structure of the cell and how these structures evolve over time, stochasticity being a consequence of the need to ignore a large number of factors while modeling relatively few in an extremely complex environment.  相似文献   

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In food-web studies, parasites are often ignored owing to their insignificant biomass. We provide evidence that parasites may affect trophic transfer in aquatic food webs. Many phytoplankton species are susceptible to parasitic fungi (chytrids). Chytrid infections of diatoms in lakes may reach epidemic proportions during diatom spring blooms, so that numerous free-swimming fungal zoospores (2-3 microm in diameter) are produced. Analysis shows that these zoospores are rich in polyunsaturated fatty acids and sterols (particularly cholesterol), which indicates that they provide excellent food for zooplankters such as Daphnia. In life-table experiments using the large diatom Asterionella formosa as food, Daphnia growth increased significantly in treatments where a parasite was present. By grazing on the zoospores, Daphnia acquired important supplementary nutrients and were able to grow. When large inedible algae are infected by parasites, nutrients within the algal cells are consumed by these chytrids, some of which, in turn, are grazed by Daphnia. Thus, chytrids transfer energy and nutrients from their hosts to zooplankton. This study suggests that parasitic fungi alter trophic relationships in freshwater ecosystems and may be the important components in shaping the community and the food-web dynamics of lakes.  相似文献   

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pFGE is the paralog of the formylglycine-generating enzyme (FGE), which catalyzes the oxidation of a specific cysteine to Calpha-formylglycine, the catalytic residue in the active site of sulfatases. The enzymatic activity of sulfatases depends on this posttranslational modification, and the genetic defect of FGE causes multiple sulfatase deficiency. The structural and functional properties of pFGE were analyzed. The comparison with FGE demonstrates that both share a tissue-specific expression pattern and the localization in the lumen of the endoplasmic reticulum. Both are retained in the endoplasmic reticulum by a saturable mechanism. Limited proteolytic cleavage at similar sites indicates that both also share a similar three-dimensional structure. pFGE, however, is lacking the formylglycine-generating activity of FGE. Although overexpression of FGE stimulates the generation of catalytically active sulfatases, overexpression of pFGE has an inhibitory effect. In vitro pFGE interacts with sulfatase-derived peptides but not with FGE. The inhibitory effect of pFGE on the generation of active sulfatases may therefore be caused by a competition of pFGE and FGE for newly synthesized sulfatase polypeptides.  相似文献   

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The steam-distilled faeces of adult male boll weevils, Anthonomus grandis, that had been injected with acetate-114C, acetate-214C, mevalonic acid-214C, or glucose14C(U) showed by column and gas chromatography that approximately 0·02 per cent of the administered radioactivity was incorporated into the volatile fraction. Also, 4 components of the pheromone comprised 57 to 80 per cent of the radioactivity of the volatiles but only 39 per cent of the total content of volatiles. Thus, evidence was obtained for de novo synthesis of the components. Although the boll weevil is essentially an obligate insect of cotton, this insect does not appear to require any specific component in cotton for biosynthesis of the pheromone.  相似文献   

18.
The genera and species in six families of the eugregarine suborder Aseptatorina Chakravarty, 1960, are reviewed and the presently accepted ones are listed: Aikinetocystidae Bhatia, 1930 (two genera and two species); Diplocystidae Bhatia, 1930 (one genus and eight species); Allantocystidae tocystidae Bhatia, 1930 (one genus and one species); Schaudinnellidae Poche, 1913 (one genus and one species); Ganymedidae Huxley, 1910 (one genus and one species); and Enterocystidae Codreanu, 1940 (one genus and eight species). A list of 22 synonyms and lapsi calami is also given. Species which might be of value in the biological control of disease vectors are indicated.  相似文献   

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