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1.
湖北植被区划(下)   总被引:14,自引:2,他引:12  
Ⅰ_2 湖北南部中亚热带常绿阔叶林地带本植被地带居湖北南半部,位于英山、罗田、新洲、黄陂、天门、荆门、远安、兴山一线以南。东部为幕阜山脉北坡,以丘陵低山地貌为主,中部为坦荡的冲积平原,大小湖泊星罗棋布,是湖北水生植物分布最广的区域;西部为武陵山系的东北麓,以山地丘陵为特点。年均温16℃以上,≥10℃年积温4800—5600℃,为本省区两个高温区域之所在,无霜期在250天以上,年降水量1100—1600毫米。长江贯穿全境,还有众多的大  相似文献   

2.
本植被地带居湖北南半部,位于英山、罗田、新洲、黄陂、天门、荆门、远安、兴山一线以南。东部为幕阜山脉北坡,以丘陵低山地貌为主,中部为坦荡的冲积平原,大小湖泊星罗棋布,是湖北水生植物分布最广的区域;西部为武陵山系的东北麓,以山地丘陵为特点。年均温16℃以上,≥10℃年积温4800—5600℃,为本省区两个高温区域之所在,无霜期在250天以上,年降水量1100—1600毫米。长江贯穿全境,还有众多的大小支流。  相似文献   

3.
We discuss the usefulness of the concept of Potential Natural Vegetation (PNV), which describes the expected state of mature vegetation in the absence of human intervention. We argue that it is impossible to model PNV because of (i) the methodological problems associated to its definition and (ii) the issues related to the ecosystems dynamics.We conclude that the approach to characterizing PNV is unrealistic and provides scenarios with limited predictive power. In places with a long‐term human history, interpretations of PNV need to be very cautious, and explicit acknowledgement made of the limitations inherent in available data.  相似文献   

4.
神农架龙门河地区的植被制图及植被现状分析   总被引:8,自引:1,他引:7       下载免费PDF全文
依据龙门河地区所处位置的植被地理分布规律性 ,绘制了该地区 1∶50 0 0 0的植被复原图。并在野外调查、资料搜集的基础上 ,辅以全球定位系统 (GPS)、GIS软件及TM影像数据 ,绘制了该地区 1∶50 0 0 0的植被类型图。结果表明 :1 )植被海拔分布由低至高依次为常绿阔叶林 (海拔 90 0m以下 ) ,硬叶常绿阔叶林 (海拔 90 0~ 1 30 0m)、常绿落叶阔叶混交林 (海拔 1 30 0~ 1 60 0m)以及落叶阔叶林 (海拔 1 60 0~ 2 2 0 0m)。 2 )龙门河地区林地面积 441 9.2hm2 ,占该地区总面积的 93 .71 % ,共计 8个植被型 65个群系。其中常绿落叶阔叶混交林面积最大 ,为 1 674.0 9hm2 ,占林地面积的 37.88%。另外 ,果园 (3种类型 )和农田两种农业用地面积 2 2 8.1 2hm2 ,占总面积的 4 .84%。 3)由植被复原图与现状植被类型图叠加分析可知 ,干扰后增加了针叶林、针阔混交林、灌丛、草地 4种植被类型 ,占龙门河地区总面积的 34 .6 %。其中针阔混交林所占面积最大 ,996 .79hm2 。  相似文献   

5.
陕西佛坪自然保护区植被的基本特征   总被引:14,自引:2,他引:12  
对陕西佛坪自然保护区植被优势植物的区系地理特征,主要植被类型及其时空动态特征进行了讨论。本区属中国-日本森林植物区系的一部分,温带分布属占较大比例,热带分布属也占相当比重,低中山森林植被优势植物以华中、华北及华东成分为主,亚高山灌丛及草甸则主要由唐古特成分及中国-喜马拉雅成分构成,本区可被视为我国温带植物区系的典型地区。本区植被可分为3个垂直自然带;(1)落叶阔叶栎林带(2000m以下);(2)落  相似文献   

6.
九宫山自然保护区植被及其特征的初步研究   总被引:4,自引:2,他引:2  
九宫山自然保护区位于中国中亚热带向北热带过渡区,植被构成以森林植被为主。通过调查和分析,将九宫山自然保护区植被划分为5个植被型组,11个植被型,32个群系。九宫山自然保护区的种子植物区系分布中温带性质和热带性质的属分别为384和302属;植被类型中主要森林植的构成为:暖温性、温性和寒温性针叶林群系数目依次是1、1、0,常绿阔叶林、落叶常绿阔叶混交林和落叶阔叶林群系数目分别为3、7、7;森林植被中落叶常绿阔叶混交林的分布面积最大。与井冈山自然保护区、庐山、后河自然保护区、清凉峰自然保护区、神农架自然保护区以及董寨鸟类自然保护区等地植被相关特征的比较分析表明,该区植被种子植物的主要组成种类以及森林植被类型和分布等具有明显的地带性过渡特性。  相似文献   

7.
东莞大屏嶂森林公园的现状植被及林分改造对策   总被引:10,自引:0,他引:10  
杨加志  苏志尧  许月明 《生态科学》2004,23(2):144-146,153
采用改进的线路调查方法对东莞大屏障森林公园植被进行调查。结果表明大屏障森林公园植物种类多样,植物资源丰富。公园的现状植被可以划分为5个类型,8个亚型。森林可分为次生常绿阔叶林、人工马占相思林Acacia mangium、油茶林Camellia oleifera等3个亚型。此外,还有荒草坡、农田植被以及其他类型的植被。据此探讨了对大屏障森林公园植被的改造对策,为森林公园的建设提供依据。  相似文献   

8.
The optimum vegetation indexand methods for collecting vegetation information in loess plateau area were studied and appraised. In this area, there were deciduous broadleaved forest, steppe and desert. Vegetation types were rich and diverse. However, collection of vegetation information was strongly influenced by the soil background. The modified soil-adjusted vegetation index (MSAVI) after being compared and analysed not only could enhance vegetation signal, but also could minimize greatly the soil background effects. It could also reflect the distribution of the vegetation types macroscopically in this area. At present, it has been a more or lessideal vegetation index for collection vegetation information in loess plateau area. The collection and monitering of vegetation information for the normalized difference vegetation index (NDVI), soil-adjusted vegetation index (SAVI) and perpendicular vegetation index (PVI) were used in high, medium density and rare vegetation area respectively. For a variety of vegetation indices, the images which were produced by cumulative multitemporal vegetation indices could extract vegetation information well reflecting the vegetation distribution of that particular area.  相似文献   

9.
论滇南西双版纳的森林植被分类   总被引:3,自引:0,他引:3  
朱华 《云南植物研究》2007,29(4):377-387
本文基于多年研究成果的总结,对西双版纳森林植被的分类、主要植被类型及其特征进行了系统归纳,并讨论了它们与世界类似热带森林植被的关系。以群落的生态外貌与结构、种类组成和生境特征相结合作为植被分类的原则和依据,可以将西双版纳的热带森林植被分类为热带雨林、热带季节性湿润林、热带季雨林和热带山地常绿阔叶林四个主要的植被型,包括有至少二十个群系。热带雨林包括热带季节雨林和热带山地(低山)雨林二个植被亚型。热带季节雨林具有与赤道低地热带雨林几乎一样的群落结构和生态外貌特征,是亚洲热带雨林的一个类型,但由于发生在季风热带北缘纬度和海拔的极限条件下,受到季节性干旱和热量不足的影响,在其林冠层中有一定比例的落叶树种存在,大高位芽植物和附生植物较逊色而藤本植物和在叶级谱上的小叶型植物更丰富,这些特征又有别于赤道低地的热带雨林。热带山地雨林是热带雨林的山地亚型,是该地区热带山地较湿润生境的一种森林类型,它在植物区系组成和生态外貌特征上类似于热带亚洲的低山雨林,隶属于广义热带雨林植被型下的低山雨林亚型。热带季节性湿润林分布在石灰岩山坡中、上部,在群落外貌上类似热带山地常绿阔叶林但在植物区系组成上与后者不同,它是石灰岩山地垂直带上的一种植被类型。热带季雨林是分布在该地区开阔河谷盆地及河岸受季风影响强烈的生境的一种热带落叶森林,是介于热带雨林与萨王纳之间的植被类型。热带山地常绿阔叶林(季风常绿阔叶林)是西双版纳的主要山地植被类型,它分布在热带季节雨林带之上偏干的山地生境。它在植物区系组成上不同于该地区的热带季节雨林,在生态外貌特征上亦不同于热带山地雨林,是发育在受地区性季风气候强烈影响的热带山地的一种森林植被类型。  相似文献   

10.
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   

11.
黄土高原地区提取植被信息方法的研究   总被引:16,自引:0,他引:16  
研究评价了适于黄土高原地区植被信息提取的最佳植被指数和方法。该地区分布有落叶阔叶林、草原和荒漠,植被类型丰富多样。然而土壤背景对植被信息提取有较大影响。经对比分析,修正后的土壤调节植被指数(MSAVI), 不仅能增强植被信号,并能大大减小土壤背景的影响,同时又能宏观地反映该地区植被类型的分布状况。它是黄土高原地区目前提取植被信息较好的植被指数。标准化差值植被指数(NDVI)、土壤调节植被指数(SAVI)和垂直植被指数(PVI)分别适用于高密度、中等密度和稀少植被地区植被信息的提取和监测。各种植被指数多时象累加产生的图像能较好地提取植被信息  相似文献   

12.
中国森林生态系统的植物碳储量和碳密度研究   总被引:7,自引:2,他引:5  
提高森林生态系统C贮量的估算精度,对于研究森林生态系统向大气吸收和排放含C气体量具有重大意义.中国的森林生态系统植物C贮量的研究刚刚开始,由于估算方法问题,不同估算结果存在着较大的差异.本研究以各林龄级森林类型为统计单元,得出中国森林生态系统的植物C贮量为3.26~3.73Pg,占全球的0.6~0.7%;各森林类型和省市间有较大的差异.森林生态系统植物C密度在各森林类型间差异比较大,介于6.47~118.14Mg·hm-2,并且有从东南向北和西增加的趋势.这种分布规律与我国人口密度的变化趋势正好相反,两者有一种对数关系.这说明我国实际森林植物C密度大小首先取决于人类活动干扰的程度.  相似文献   

13.
湖北西陵峡地区的植被   总被引:7,自引:1,他引:6  
湖北西陵峡地区处于我国亚热带向暖温带过渡的区域,植被及植物成分具有明显的过渡特征,其类型及其种类极为复杂。本文重点探讨该地区主要的植被类型组合及分布情况,计自然植被有5个植被型,9个群系纲,15个群系组,46个群系;人工植被有1个植被型,2个群系纲,5个群系组,8个群系。  相似文献   

14.
ZHU Hua 《Plant Diversity》2007,29(4):377-387
Xishuangbanna of southern Yunnan is a region of extremely interest to biologists and also a hotspot for biodiversity conservation . It is located in a transitional zone from tropical Southeast Asia to temperate East Asia biogeographically. The present paper reviewed vegetation types of Xishuangbanna and suggested a revised classification system based on theupdated study results over the last two decades . By combining physiognomic and floristic characteristics with ecological performances and habitats , the primary forest vegetation in Xishuangbanna can be organized into four main vegetation types: tropical rain forest, tropical seasonal moist forest, tropical montane evergreen broad-leaved forest and tropical monsoon forest. The tropical rain forest can be classified into two subtypes , i. e. tropical seasonal rain forest in the lowlands and tropical montane rain forest on higher elevations. The tropical seasonal rain forest in this region shows similar forest profile and physiognomic characteristics to those of equatorial lowland rain forests and is a type of world tropical rain forest. Because of conspicuous similarity on floristic composition , the tropical seasonal rain forest in Xishuangbanna is a type of tropical Asian rain forest . However , since the tropical seasonal rain forest occurs at the northern edge of tropical SE Asia, it differs from typical lowland rain forests in equatorial areas in maintaining some deciduous trees in the canopy layer , fewer megaphanerophytes and epiphytes but more abundant lianas and more plants with microphyll . It is a type of semi-evergreen rain forest at the northern edge of the tropical zone . The tropical montane rain forest occurs in wet montane habitats and is similar to the lower montane rain forests in equatorial Asia in floristic composition and physiognomy . It is a variety of lower montane rain forests at the northern tropical edges of tropical rain forests . The tropical seasonal moist forest occurs on middle and upper limestone mountains and is similar to the tropical montane evergreen broad-leaved forest of the region in physiognomy, but it differs from the latter in floristic composition. The monsoon forest in Xishuangbanna is a tropical deciduous forest under the influence of a strong monsoon climate and is considered to be a transitional vegetation type between tropical rain forest and savanna in physiognomy and distribution. The tropical montane evergreen broad- leaved forest is the main vegetation type in mountain areas . It is dominated by the tree species of Fagaceae , Euphorbiaceae , Theaceae and Lauraceae in majority. It differs from the tropical montane rain forests in lack of epiphytes and having more abundant lianas and plants with compound leaves . It is considered to be a distinct vegetation type in the northern margin of mainland southeastern Asia controlling by a strong monsoon climate, based on its floristic and physiognomic characteristics.  相似文献   

15.
清澜红树林保护区位于海南岛东北部文昌市境内,为全面了解其植物多样性,对其各类植被进行了调查。共记录到维管植物172种,隶属于62科148属。其中真红树植物24种,占全省真红树(26种)的92.31%,占全国(28种)的85.71%,占全世界(86种)的27.91%;在4040 m2样地内,共记录到高度1.5 m以上的红树植物29种3670株,其中重要值最高的为海桑Sonneratis caseolaris,其次是海莲Bruguiera sexangula,两者重要值依次是12.90和12.33;但在个体数量上,角果木Ceriops tagal和红海榄Rhizophora stylosa占优势。清澜港红树林保护区自然植被具体划分为1个植被类型组、1个植被类型、2个群系组和12个群系。经过19年的演变,木榄Bruguiera gymnorrhiza和水椰Nypa fruticans群落消失,瓶花木Scyphiphora hydrophyllacea群落也破碎成零星分布,新出现了木果楝Xylocarpus granatum群落,其他如海桑Sonneratia caseolaris等群落则继续保持稳定,变化很小。  相似文献   

16.
中国森林生态系统的植物碳储量和碳密度研究   总被引:221,自引:8,他引:213  
提高森林生态系统C贮量的估算精度,对于研究森林生态系统向大气吸收和排放含C气体量具有重大意义.中国的森林生态系统植物C贮量的研究刚刚开始,由于估算方法问题,不同估算结果存在着较大的差异.本研究以各林龄级森林类型为统计单元,得出中国森林生态系统的植物C贮量为3.26~3.73Pg,占全球的0.6~0.7%;各森林类型和省市间有较大的差异.森林生态系统植物C密度在各森林类型间差异比较大,介于6.47~118.14Mg·hm-2,并且有从东南向北和西增加的趋势.这种分布规律与我国人口密度的变化趋势正好相反,两者有一种对数关系.这说明我国实际森林植物C密度大小首先取决于人类活动干扰的程度.  相似文献   

17.
Tropical savannas commonly exhibit large spatial heterogeneity in vegetation structure. Fine-scale patterns of soil moisture, particularly in the deeper soil layers, have not been well investigated as factors possibly influencing vegetation patterns in savannas. Here we investigate the role of soil water availability and heterogeneity related to vegetation structure in an area of the Brazilian savanna (Cerrado). Our objective was to determine whether horizontal spatial variations of soil water are coupled with patterns of vegetation structure across tens of meters. We applied a novel methodological approach to convert soil electrical resistivity measurements along three 275-m transects to volumetric water content and then to estimates of plant available water (PAW). Structural attributes of the woody vegetation, including plant position, height, basal circumference, crown dimensions, and leaf area index, were surveyed within twenty-two 100-m2 plots along the same transects, where no obvious vegetation gradients had been apparent. Spatial heterogeneity was evaluated through measurements of spatial autocorrelation in both PAW and vegetation structure. Comparisons with null models suggest that plants were randomly distributed over the transect with the greatest mean PAW and lowest PAW heterogeneity, and clustered in the driest and most heterogeneous transect. Plant density was positively related with PAW in the top 4 m of soil. The density-dependent vegetation attributes that are related to plot biomass, such as sum of tree heights per plot, exhibited spatial variation patterns that were remarkably similar to spatial variation of PAW in the top 4 m of soil. For PAW below 4 m depth, mean vegetation attributes, such as mean height, were negatively correlated with PAW, suggesting greater water uptake from the deep soil by plants of larger stature. These results are consistent with PAW heterogeneity being an important structuring factor in the plant distribution at the scale of tens of meters in this ecosystem.  相似文献   

18.
Question: Is it possible to translate vegetation maps into reliable thematic maps of site conditions? Method: This paper presents a new method, called Iteratio, by which a coherent spatial overview of specific environmental conditions can be obtained from a comprehensive vegetation survey of a specific area. Iteratio is a database application which calculates environmental indicator values for vegetation samples (relevés) on the basis of known indicator values of a limited number of plant species. The outcome is then linked to a digitalized vegetation map (map of plant communities) which results in a spatial overview of site conditions. Iteratio requires the indicator values of a minimum of 10–20% of the species occurring. The species are given a relative weight according to their amplitudes: species with a narrow range are weighted stronger, species with a broad range are weighted weaker. Conclusion: The method presented here enables a coherent assessment of site conditions on the basis of a vegetation survey and the indicator values of a limited number of plant species.  相似文献   

19.
20.
Results of pollenanalytical investigations in the Highlands of Mexico (area of Puebla — Tlaxcala) are presented together with a survey of the last 35 000 years of vegetation history. After 3 pine periods from 35 000 to about 7 000–8 000 B. P., according to high and late Pleistocene condition, the Holocene vegetation history becomes more diversified: periods of alder, pine, fir and mixed oak forests alternate and end in a period of cultivated landscape.  相似文献   

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