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1.
安徽升金湖自然保护区湿地草本种子植物区系研究   总被引:8,自引:1,他引:7  
对安徽升金湖湿地自然保护区的湿地草本植物区系进行了初步分析,研究表明,该区共有湿地草本种子植物59科173属275种,以禾本科(Gramineae)、菊科(Compositae)、莎草科(Cyperaceae)等为优势科,而以菱科(Trapaeeae)、三白草科(Saururaceae)、茨藻科(Najadaceae)等为该植物区系的表征科;以蓼属(Polygonum)、苔草属(Carex)、蒿属(Artemisia)等为优势属,但属的组成较为分散,寡种属和单种属占总属数的97.69%,表明该区植物成分较为复杂,物种多样性指数较高。从分布区类型看,科以热带成分占明显优势(30.52%);属泛热带分布属最多(21.39%),北温带分布成分次之(13.87%),总体上温带成分(38.73%)略多于热带性成分(34.10%)。表明该植物区系地理成分复杂,过渡性明显,分布区类型多样,具有热带、亚热带与暖温带的多重性质,但以亚热带性质为主。  相似文献   

2.
小五台山自然保护区苔藓植物研究   总被引:4,自引:0,他引:4  
根据对小五台山国家级自然保护区苔藓植物资源的实地调查和室内鉴定,该文分析了保护区内苔藓植物区系的基本组成,统计了科、属、种的数目及其优势科、属;讨论了苔藓植物的10种区系成分及其区系特征,其中北温带成分居主导地位,针对苔藓植物资源的现状,提出合理开发利用的建议。  相似文献   

3.
怒江峡谷区植物资源及其评价   总被引:4,自引:0,他引:4  
怒江峡谷特殊的自然地理环境和立体气候,孕育出种类丰富的植物资源,新老、珍稀、孑遗和特有种兼备。有维管束植物185科878属3138种(包括亚种和变种),其中蕨类植物41科101属374种,裸子植物5科12属22种,被子植物139科765属2742种。峡谷区科属种分类分别占云南同类植物的56.74%、40.46%和20.79%,占横断山区的84.47%、59.95%和36.66%;植物区系成分复杂多样,各类热带分布属(不含世界分布,下同)352个,占峡谷区总属数的45.30%;各类温带分布属346个,占峡谷区总属数的44.53%;地中海或泛地中海分布仅16属,占峡谷总属数的2.05%;中国特有属17个,占峡谷区总属数的2.18%。近期有开发前景的植物资源种类多,且门类齐全,是当地各民族脱贫致富,建设家乡的宝贵财富。立足植物资源,面向市场,以科学技术为先导,大力发展名特中药材、多维果类、油料植物、花卉和食用菌等,形成名、特产品,参加国内外市场竞争。建议成立生物资源开发领导机构,建立生物产品生产基地和加工工业,进行集约化生产,重视和加强科学技术和教育投入,制订有关生物资源开发的优惠或特殊政策。  相似文献   

4.
为了掌握石首市天鹅洲湿地野生维管束植物的组成与地理分布,对其进行了全面的野外调查。研究结果表明,天鹅洲湿地野生维管束植物共有45科125属148种,其中,有蕨类植物2科2属2种,被子植物43科123属146种;该区系野生维管束植物主要由草本植物组成,其科(43科)、属(118属)和种(140种)的优势明显;双子叶植物(37科96属120种)构成了天鹅洲湿地野生维管束植物区系的主体。天鹅洲湿地野生维管束植物的分布区系类型多样,在植物科的水平上,有5类型3变型,在植物属的水平上,有12类型7变型,在植物种的水平上,有14类型11变型,表明该区系地理成分复杂,与其它区系联系广泛;温带成分略占优势,反映出该区系从亚热带到温带过渡的区系特点;无特有属,特有种匮乏,仅有1种。  相似文献   

5.
为了掌握石首市天鹅洲湿地野生维管束植物的组成与地理分布,对其进行了全面的野外调查。研究结果表明,天鹅洲湿地野生维管束植物共有45科125属148种,其中,有蕨类植物2科2属2种,被子植物43科123属146种;该区系野生维管束植物主要由草本植物组成,其科(43科)、属(118属)和种(140种)的优势明显;双子叶植物(37科96属120种)构成了天鹅洲湿地野生维管束植物区系的主体。天鹅洲湿地野生维管束植物的分布区系类型多样,在植物科的水平上,有5类型3变型,在植物属的水平上,有12类型7变型,在植物种的水平上,有14类型11变型,表明该区系地理成分复杂,与其它区系联系广泛;温带成分略占优势,反映出该区系从亚热带到温带过渡的区系特点;无特有属,特有种匮乏,仅有1种。  相似文献   

6.
2022年6月至11月期间,在福建长汀汀江国家湿地公园中,采用调查样线方法和重点普查方法,开展了维管植物野外调查,建立了维管植物名录,分析了维管植物的组成和地理成分。研究结果表明,调查期间,在该湿地公园中记录了114科299属424种维管植物,其中,有蕨类植物15科24属32种,有裸子植物5科5属5种,有被子植物94科270属387种;禾本科(Poaceae)、菊科(Asteraceae)、莎草科(Cyperaceae)和豆科(Fabaceae)为优势科,分别包含34属48种、22属33种、11属22种和15属20种维管植物,优势属不明显;维管植物的科和属的区系都既有明显的热带属性,又有一些温带成分;维管植物的区系丰富程度和种系分化程度都较低,维管植物的生存环境相对简单。  相似文献   

7.
北京地区湿地高等植物区系分析   总被引:2,自引:5,他引:2  
李满良  张铁明  胡东  陈卫 《湿地科学》2006,4(3):219-226
根据工作需要,在北京4个水系的主要河流的平原地段和山区的上、中游地段,选取不同生境的典型样地,以及城区的人工湖泊共设立了35个采集点,采用样方法和样带法相结合,共调查样方355个,采集样本4 152个。在该调查资料的基础上,运用区系学原理对北京地区湿地高等植物区系的种类组成、地理成分(科、属、种3个层次)等进行了系统的分析。结果表明,北京地区湿地高等植物共有108科311属552种(含山区湿地),占北京植物总数的近1/3。其中苔藓植物(B ryohyto)有9科15属18种;蕨类植物(Pteridophgta)5科5属8种;裸子植物(Gymnosperm ae)3科5属6种;被子植物(Angiosperm ae)91科286属520种。种子植物中含20种以上的有5科,共210种;含5种以上的属有14个属,共114种。北京地区湿地植物的分布(即地理成分)较复杂。北京湿地种子植物属的分布区类型有15个类型,9个变型,温带地区类型占主导,温带成分较丰富(属数、种类、比例均占首位)。本区植物区系的主要特征为:①草本植物发达;②温带成分占优势地位;③区系起源古老;④特有属、种匮乏;⑤分布区类型具多样性。  相似文献   

8.
广东博罗县小金河植物区系研究   总被引:1,自引:0,他引:1  
王英强  陈邦余 《热带地理》1995,15(4):350-361
本区计有野生维管束植物172科、532属、978种(包括变种、变型)。发现2新种,1新变种和3个广东新记录种。本区系的表征科为山茶科、壳斗科、桑科、芸香科、紫金牛科、樟科等,这些科大都是热带-亚热带分布式的,代表了本区系的性质。在属的地理成分中,本区以热带成分173属(占总数的35.2%)和热带-亚热带成分169属(占总数的34.4%)为主,说明了本区系具有由亚热带向热带过渡的南亚热带特征。本区与  相似文献   

9.
根据对小五台山国家级自然保护区苔藓植物资源的实地调查和室内鉴定,该文分析了保护区内苔藓植物区系的基本组成,统计了科、属、种的数目及其优势科、属;讨论了苔藓植物的10种区系成分及其区系特征,其中北温带成分居主导地位,针对苔藓植物资源的现状,提出合理开发利用的建议。  相似文献   

10.
浙江丽水山地蕨类植物区系   总被引:2,自引:0,他引:2  
朱圣潮 《山地学报》2003,21(6):686-694
浙江丽水山地蕨类植物资源十分丰富,区系由42科92属325种(含变种)组成。主要的科是鳞毛蕨科、水龙骨科、蹄盖蕨科、金星蕨科和铁角蕨科;主要的属是鳞毛蕨属、复叶耳蕨属、铁角蕨属、蹄盖蕨属和卷柏属。区系起源古老,不乏古老的科、属及残遗种,且区系成分复杂,来源于多种地理成分。  相似文献   

11.
建设广州国际大都市的市区街道绿化   总被引:8,自引:2,他引:8  
郑芷青 《热带地理》1995,15(1):62-69
本文运用生态学方法,分析了广州市行道林生物群落、生态质量、空间分布特征及生态环境作用。在此基础上,提出了建设广州国际大都市街道绿化的建议。  相似文献   

12.
广州华侨新村低密度住宅区庭院的树木和景观研究*   总被引:1,自引:0,他引:1  
对广州华侨新村低密度住宅区庭院树木的组成、结构、空间格局、树木与生境的关系,以及私人庭院树木与公共绿地的不同特点进行了研究。结果表明:华侨新村庭院树木的种类多样性很高,共有114个树种。与广州城市行道树相比,华侨新村的乡土树种和果树比例较高。在调查的树木中84.75%的树木没有结构损伤现象,只有1.5%的树木生长较差。私人庭院内的树种较为分散,有45种树木为每个庭院仅一棵的单生种,有67.1%的庭院其树种在5种或以上。树木在街道的空间分布则有相对集中的趋势。庭院的大小是影响树木生长的重要条件,在有限空间的庭院内种植过多的树木是造成树木和环境关系紧张的重要原因。  相似文献   

13.
Pinus taiwanensis is a species endemic to China. This study selected four typical plots of Pinus taiwanensis in the natural secondary forest around Macheng City, in order to reveal the characteristics of and the relationships between different diameter classes (determined based on the diameter at breast height or DBH), forest densities and species diversity, as well as the similarities of species diversity of different plots within the community. The result showed that Pinus taiwanensis was the dominant species in the community. The ratio of Pinus taiwanensis trees of diameter class IV reached a peak of 19.46% of the total followed by diameter class VII at 18.92%. The study recorded 156 species of vascular plants from 130 genera of 71 families; Pinus taiwanensis was the dominant species in the community. When the forest density was 1200 trees ha -1 with the largest average diameter of DBH=36.779±4.444 cm, the diversity (Shannon index H'=1.6716) and the evenness (Pielou index E=0.6727) of the tree layer was the highest. When the forest density reached 1525 trees ha -1 with the lowest average diameter of DBH=18.957±5.141 cm, the richness (Dma=5.4308), the diversity (H'=2.9612) and the evenness (E=0.8985) of all shrub layers climbed to the maximum. When the forest density was 1325 trees ha -1, the richness (Dma=5.8132), the diversity (H'=3.0697) and the evenness (E=0.9025) of all herb layers peaked. In terms of vertical structure, the average diversity indexes were herb layer>shrub layer>tree layer. High canopy density weakened light intensity in the community, causing a reduction in the species diversities of herbs and shrubs. The average similarity coefficient between the sample plots was 0.3356, which was at the medium dissimilarity level. External disturbances and improper management were major contributors to the low species diversity of the community. The implementation of scientific management measures is urgently needed to optimize the forest structures of Pinus taiwanensis, create a benign community environment, and promote species diversities and establish a stable forest community structure.  相似文献   

14.
以赣南红壤崩岗侵蚀区野外调研孢粉资料为基础,分析了8个表土样品。结果发现:赣南红壤崩岗侵蚀区表土样品孢粉种属类型丰富,共鉴定出131种,统计有效孢粉2 694粒;表土孢粉组合为乔木、灌木、草本、蕨类和苔藓植物,其中乔木和蕨类植物的孢粉占优势,平均分别为48.49%和37.10%,灌木和草本花粉含量较低,平均为3.00%和8.43%。乔木植物中的马尾松(Pinus massoniana)平均浓度为28.0%,蕨类植物中里白厥(Hicriopterisglauca)平均浓度为26.09%,均具有超代表性;植物花粉亚热带特征明显;不同母岩崩岗侵蚀区优势科属种方面存在一定的差异;孢粉组合反映出马尾松、里白蕨对红壤崩岗生态环境的适应性和代表性。该研究为今后在这一地区开展第四纪古植被、古气候和古环境等研究提供参考性依据,同时也为南方崩岗治理筛选先锋植物提供参考。  相似文献   

15.
广州市居住区环境绿化的探讨   总被引:4,自引:0,他引:4  
郑芷青 《热带地理》2005,25(3):243-247
运用景观生态学方法,通过实地调查和统计分析,对广州市居住区的环境绿化现状、问题进行了研究和分析,认为居住区绿地指标多数未达标,绿化类型简单,绿地布局不合理,树种的选择单调、雷同和绿化管理水平较低,并就此提出要重视搞好居住区绿化规划设计,确保绿化达标、绿地类型多样和布局合理,完善点、线、面的绿地系统,要选择多样的树种,合理配置,加强绿化宣传和管理等建议和对策。  相似文献   

16.
The flora of Israel, like in other arid regions, has many spiny plants. We describe their existence in the archaeobotanical record of the last 780,000 years. Of 246 spiny/thorny species in the current flora, 19 are trees, 37 are shrubs, 50 are half-shrubs, 83 are perennial herbs and 57 are annuals. Forty-six (18.7%) spiny/thorny species were identified in the archaeobotanical record: 15 tree species (78.9%), ten shrub species (27.0%), six half-shrub species (12.0%), three perennial herb species (3.6%) and 12 annuals (21.1%). Because humans needed wood, trees were taken into their habitats. Since trees are better preserved than herbaceous plants and shrubs their remains are more common. Only a small proportion of the spiny/thorny half-shrubs and perennial herbs was found, probably because they are not a good source of firewood, construction materials, or human food. Spiny weeds, and segetal and ruderal plants entered the archaeobotanical remains either by chance, as seeds contaminating grain and fodder, growing at the sites, or through their deliberate use by ancient peoples as supplementary foods and medicine. The identified spiny/thorny species in the archaeobotanical record of Israel indicates that the flora was always spiny even before the significant human impact in the last several millennia.  相似文献   

17.
千庆兰 《热带地理》2002,22(1):90-92,96
城市生态环境质量是影响城市景观和居民身心健康的重要因素,环境质量分区是进行生态环境评价的基础性工作。在以往生态环境质量评价中,通常采用单一的环境污染指标,难以全面综合的反应生态环境质量状况。植被的面貌是一定时期内大气、土壤、水分、人类活动综合作用的结果。由于树木有生命而又不能移动,它的健康状态是一定时期因素内,综合地反映其生活环境条件的最好尺度。借鉴国外环境诊断的研究方法,提出“树木活力度”,即树木的枝、叶、梢、树形等各个部位的生长状况和健康程度这一新的综合生态指标,并结合实际,以吉林市为例,对运用这一指标进行城市生态环境质量评价的方法、原理、问题等进行了初步探讨。指出运用树木活力度进行城市生态环境质量分区,具有迅速目测、计算简便,快速经济的特点,是当前较为流行的一种景观诊断的简便易行的方法。  相似文献   

18.
There have been a great number of debates about the impacts of trees on crimes: some researchers believed that trees are a crime facilitator because of the concealment provision for potential criminals, while others argued that they are a crime deterrent because of the increased surveillance possibility and the therapeutic effect on psychological fatigue. To better answer this question, this study incorporated detailed tree features by using multi-source remotely sensed data at a very high resolution into environmental criminology analysis across the entire City of Milwaukee. Trees were extracted from aerial photographs, and broken down into two categories based on their heights to consider the effects of tree height on view obstruction. By controlling for confounding socioeconomic variables, the relationship between crimes and a series of composition and configuration indicators of trees with different height were investigated by using global and local spatial regressions. Results from classic and spatial statistical techniques finds complicated relationship between crimes and trees, which can be summarized in two aspects. First, the mixed effects of trees can be observed among different crime types. Second, the trends of spatial nonstationarity of the composition and configuration of trees with different heights were observed across the entire study area. The study outcomes could provide reasonable implications for making appropriate policies for crime prevention through environmental design to strengthen neighborhoods and communities in a city.  相似文献   

19.
植物枝条失去50%水分传导时对应的水势(ψ50),称为枝的水分传导脆弱性。该指标是反映植物干旱适应能力的关键指标,也决定着植物沿降水梯度的分布。乔木和灌木枝水分传导脆弱性沿降水量递增的变化是否一致,有待揭示。基于已发表的文献,筛选出236种乔木、137种灌木,建立ψ50与分布地年均降水量及分布地干旱指数关系,来确认两大类植物的ψ50沿降水递增的变化的异同。结果表明:乔木和灌木的ψ50均随降水梯度、干旱指数的增加而增加,一元线性回归方程显著;ψ50与降水梯度、干旱指数回归方程的回归系数在乔木和灌木间差异不显著,但同一降水量下,乔木比灌木具有较低的ψ50值。我们认为灌木和乔木枝水分传导脆弱性对降水量和干旱指数递增具有相似的适应性。  相似文献   

20.
An inventory of trees in Dublin city centre   总被引:2,自引:0,他引:2  
While urban areas are often considered to be comprised chiefly of artificial surfaces, they can contain a substantial portion of green space and a great diversity of natural habitats. These spaces include public parks, private gardens and street trees, all of which can provide valuable environmental services, such as improved air quality. Trees play a particular role in cities as they are often placed along roadsides and in the median strip of busy streets. As such they regulate access to sunshine, restrict airflow, provide shelter, scavenge air pollutants and manage noise at the street level. A tree planting policy can be an important part of a broader environmental strategy aimed at improving the quality of life in urban areas but this requires up-to-date knowledge of the current tree stock, which does not exist for Dublin. This article presents an inventory of trees in Dublin's city centre, defined as the area between the Grand and Royal canals. The results show that there are over 10,000 trees in the study area representing a density of 684 trees km-2 or one tree to approximately every 50 residents of the city centre. The tree canopy extent when in full foliage was nearly 1 km2 in extent or 6% of the study area. A more detailed analysis of those trees planted along streets shows little species variation but clear distinction in the sizes of trees, which is indicative of the age of planting. These data are used to estimate the carbon stored in Dublin's trees.  相似文献   

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