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1.
广州高校校园植物调查与景观特色评价   总被引:1,自引:0,他引:1  
对广州市6所代表性高校校园植物实地调查。结果表明,6所高校共有维管植物356种,隶属87科215属。其中,校园主入口绿地区域共记录98种植物,主要应用观花、观叶植物,采用乔木+灌木+草本的垂直结构多层次配置植物景观;主干道区域共使用植物59种,以乡土树种为主;主建筑绿地区域内共应用植物97种,植物种类丰富,景观特色突出;广场绿地区域共记录植物85种,其中观花、观叶类灌木应用频率较高,观赏效果好。  相似文献   

2.
提高校园绿地植物物种多样性策略   总被引:7,自引:0,他引:7  
提高校园绿地植物物种多样性应是提高校园绿地质量的核心,也是校园绿地发挥生态调节作用和社会效益的基础,通过做好校园用地规划,科学地安排绿化用地,保护和创造多样生境,充分利用乡土植物,有节制地引进外来植物,合理密植,限制和调剂好各物种所占比例,构建复层群落结构.加强养护管理,充分发挥绿化植物的特点与功能,可提高校园绿地植物物种多样性。  相似文献   

3.
校园植物能反映校园植物多样性水平。为了研究东北地区高校校园种子植物属组成的相似性,本研究以沈阳农业大学等6所位于东北地区的高校中的校园种子植物为研究对象,并选取北方极为常见的两个科:菊科(Asteraceae)和蔷薇科(Rosaceae),研究其属组成的差异性与相似性。结果表明,6所高校校园种子植物属间相似性较高。菊科属的组成在各高校间差异性显著,蔷薇科属的组成在各高校相似性高。校园植物种类的多样性与差异性与校园面积、校园所处位置相关。本研究旨在为东北乃至其他地区高校校园生物多样性的进一步研究和其他高校校园植物调查提供基础。  相似文献   

4.
为探讨澳门路环黑沙水库植物群落与物候特征,采用群落生态学的方法,研究了黑沙水库植物群落种类组成、空间结构、多样性及重点植物物候期。结果表明,在1200 m2样地中有维管植物88种,隶属于47科80属。乔灌层无明显优势树种,草本层中淡竹叶(Lophatherum gracile)具有较显著优势,各层植物分布均匀程度差异小。群落外貌终年常绿,大部分种类各物候期存在重叠现象,萌芽展叶期持续时间长,开花期集中在5-6月,果熟期10-12月最盛。根据乡土植物群落和物候特征,筛选并推荐在澳门及邻近区域可开发的景观植物,为构建生态价值高的植被景观或植被恢复提供参考。  相似文献   

5.
北京建成区外来植物的种类构成   总被引:2,自引:0,他引:2  
大量种植外来植物已成为我国城市绿地建设的一个主要问题。开展城市建成区外来植物种类构成的研究, 可为城市植物的多样性保护及绿地的科学设计提供重要依据。本文采用分层随机抽样法, 调查了北京市五环以内的乔木样地1,050个, 灌木样地797个, 草本样地2,228个, 共记录外来维管束植物80科208属324种。统计分析的结果显示, 北京建成区植物的外来种比例高达53%, 其中64%的国外外来种来自美洲和亚洲; 不同生活型植物中以常绿植物和藤本植物的外来种比例最高。根据其盖度、密度和频度值, 北京建成区主要外来种有野牛草(Buchloe dactyloides)、凹头苋(Amaranthus blitum)、虎尾草(Chloris virgata)、大叶黄杨(Euonymus japonicus)、圆柏(Sabina chinensis)、刺槐(Robinia pseudoacacia)、白皮松(Pinus bungeana)等15种, 部分外来种已成为建成区绿地的优势植物。外来种比例最高的绿地类型是观赏性要求较高的公共设施绿地。外来植物属的区系地理分布很广泛, 与北京建成区的乡土植物相比, 热带成分的比例增加而温带成分的比例降低。北京建成区外来植物的种类构成特点反映了城市建成区为了增加观赏植物种类而人为引入大量外来植物所造成的影响。  相似文献   

6.
植被覆盖率高的线性公园,可作为鸟类的迁徙途径和栖息之所,并猜测其可作为生态廊道的一部分,适宜的营造植物景观、提升植物种类的多样性对保护鸟类多样性有促进作用。因此,采用标准取样法对北京城市线性公园绿地进行研究,提取可能影响鸟类多样性的植物群落因素、植物生境因素,对提高鸟类多样性提出建设性的意见。研究结果主要表明,在线性公园绿地宽度30~200m内,随着宽度的增加,鸟类的数量有所提高;含有不同类型植物生境的线性公园绿地,对鸟类目标种的吸引力不同,植物生境类型数较多样的线性公园绿地具有较高的鸟类目标种吸引力;不同的鸟类目标种偏好在不同的树种上进行活动。  相似文献   

7.
植物演替是指一个植物群落被另一个植物群落所取代的过程。例如在云杉林砍伐迹地上,开始是禾本科、莎草科杂草为主的群落,后来阔叶树种迅速生长,形成以桦树、山杨为主的群落,再进一步又为云杉所取代,形成云杉林。植物演替的研究是植被科学中一个极其重要的方面,运动变化是自然界一切事物的根本属性,同样,植物群落的运动发展也是其本质特征。群落变化发展的根源是组成群落的各植物个体都有其生长、发育、和死亡的过程,植物之间互相影响,不断变化的环境也时刻影响着植物,这包括由植物本身生命活动改变了的环境反过来也影响植物,这种错综复杂的关  相似文献   

8.
王俊伟  明升平  杨坤  何敏  拉琼 《广西植物》2022,42(3):384-393
生态群落交错区通常因物种丰富、区系成分复杂而被视为关键带.藏南布丹拉山处在半湿润向半干旱的生态环境过渡带上,因其特殊的自然地理环境而有着丰富的山地植物多样性,但这一重要生态过渡区的种子植物组成和区系成分海拔分布格局目前尚缺乏了解.为了理清布丹拉山南坡种子植物区系成分及其垂直分布变化格局,该文通过野外植物群落的样方调查、...  相似文献   

9.
采用样方法调查了哈尔滨市17块绿地的植物多样性,研究城市绿地生态系统中本土植物多样性对外来植物的影响规律。结果如下:哈尔滨市绿地有75种外来植物,外来栽培植物42种,外来非栽培植物33种。在哈尔滨市绿地植物群落中,外来栽培植物的平均盖度、平均重要值和平均出现频度均较高;外来非栽培种的平均盖度、平均重要值较低,而平均出现频度较高。绿地本土植物物种数与外来栽培种、外来非栽培种的物种数极显著正相关(P<0.01),与外来非栽培种的平均出现频度显著负相关(P<0.05)。绿地乔木层本土植物的香农威尔指数、物种丰富度与外来栽培种、外来非栽培种的物种数均显著负相关(P<0.05),乔木层本土植物的均匀度与外来非栽培种的平均出现频度极显著负相关(P<0.01);灌木层本土植物的物种丰富度与外来栽培种的平均重要值显著负相关(P<0.05);草本层本土植物的均匀度与外来非栽培种的平均相对盖度显著正相关(P<0.05)。随绿地总面积的增加,外来栽培种和外来非栽培种的物种数增加,平均出现频度均呈现显著降低的趋势。随建成时间增加,外来栽培种的平均出现频度呈非线形变化,外来非栽培种的平均出现频度呈现降低的趋势。应提高哈尔滨市绿地本土植物的多样性,严格控制新建成的、总面积较小的绿地中外来植物的引种栽培管理,以防止外来植物发展成为危害本地生态系统的入侵植物。  相似文献   

10.
神农架山地河岸带中珍稀植物群落特征   总被引:1,自引:0,他引:1  
以领春木(Euptelea pleiospermum)、连香树(Cercidiphyllum japonicum)为优势种的珍稀植物群落是神农架山地中海拔地段河岸带中的典型群落类型.在神农架地区4大水系(沿渡河、香溪河、南河和堵河)的河岸带中共调查了48个样地,采用植物群落学方法,分析了该区山地河岸带中珍稀植物群落特征.结果表明:(1)群落中植物种类丰富,科属组成比较分散.共记录到维管束植物749种,隶属144科412属,其中每科仅记录到1个属的有72个科,每属仅记录到1个种的有256个属.(2)在科水平上,热带、亚热带成分与温带成分所占比例几乎相同,在属水平上温带成分占主导.东亚分布成分、中国特有成分所占比例较高,共记录了6个东亚特有科、50个东亚特有属,2个中国特有科、27个中国特有属.(3)中小型草质单叶的落叶阔叶高位芽和地面芽植物是决定该珍稀植物群落外貌的主要成分.(4)群落垂直结构复杂,成层现象明显.第一乔木亚层树冠层分布不连续,第一、第二乔木亚层和灌木层从高到低郁闭度逐渐增大,草本层盖度各样地差别较大,层间植物丰富.该山地河岸带中丰富的珍稀、特有和/或孑遗植物表现出该群落的古老、孑遗性.虽然该区多数珍稀植物为温带性质,但该珍稀植物群落整体上在种类组成、区系分布、生活型谱、叶片性质等方面表现出亚热带亚高山垂直带谱上常绿落叶阔叶混交林的过渡性特征.自上而下逐渐密集的群落垂直结构为幼苗稍耐荫、成年趋于喜光的珍稀植物的不同发育阶段提供了利于其生长的光环境.特殊的地理位置、独特的地形地貌和良好的水热条件使亚热带山地河岸带成为珍稀植物(尤其是孑遗植物)就地保护中一个关键而特殊的区域.  相似文献   

11.
该文以浙江省安吉县两个典型乡村—繅舍村和赋石村为例,选取公园、农耕区、河道、人工林地四种不同土地利用类型,用Shannon-Wiener指数、Simpson指数、Sorensen指数为标识多样性的指标,分析不同生境下草本植物多样性差异。结果表明:乡村生境中共记录物种162种,分属47科123属,其中禾本科与菊科物种数占总数的31.48%;农耕区生境的Shannon-Wiener指数、Simpson指数最高,分别为2.76和0.91,农耕区与河道的Sorensen指数最高为0.57。从农耕区、河道、公园到林地生境,草本物种多样性整体呈减小趋势。另外,发现人工绿化措施会导致草本物种减少,如从种植水稻单一作物到复合作物,草本层植物随之改变。单一稻田与复合种植区比较,草本植物主要的科属组成无明显变化,莎草科、菊科、禾本科植物仍占主体;但草本植物群落主要物种组成发生变化,稻田转变成农耕区后,牛筋草、黑麦草,碎米荠、小飞蓬、喜旱莲子草成为草本层群落主要构成植物,水竹叶覆盖度减少,小飞蓬和喜旱莲子草的覆盖度增加。此外,还发现4种生境中共有喜旱莲子草、加拿大一枝黄花、土荆芥三种入侵物种,但未能对本土物种构成显著影响。这表明不同土地利用方式会严重影响草本群落物种组成及物种多样性;土地利用方式的变化,会引起草本植物主要群落构成发生改变;土地利用类型的多样化有利于本土草本物种多样性生存。该研究结果有助于为城镇化进程中保护乡村植物多样性、加速推进美丽中国建设提供技术支撑。  相似文献   

12.
Globally, biological invasions can have strong impacts on biodiversity as well as ecosystem functioning. While less conspicuous than introduced aboveground organisms, introduced belowground organisms may have similarly strong effects. Here, we synthesize for the first time the impacts of introduced earthworms on plant diversity and community composition in North American forests. We conducted a meta‐analysis using a total of 645 observations to quantify mean effect sizes of associations between introduced earthworm communities and plant diversity, cover of plant functional groups, and cover of native and non‐native plants. We found that plant diversity significantly declined with increasing richness of introduced earthworm ecological groups. While plant species richness or evenness did not change with earthworm invasion, our results indicate clear changes in plant community composition: cover of graminoids and non‐native plant species significantly increased, and cover of native plant species (of all functional groups) tended to decrease, with increasing earthworm biomass. Overall, these findings support the hypothesis that introduced earthworms facilitate particular plant species adapted to the abiotic conditions of earthworm‐invaded forests. Further, our study provides evidence that introduced earthworms are associated with declines in plant diversity in North American forests. Changing plant functional composition in these forests may have long‐lasting effects on ecosystem functioning.  相似文献   

13.
引种高等植物构建半自然湿地生态系统,是修复遭受严重污染和破坏的湖泊湿地的重要方法之一.以2011-2012年滇池湖滨区26个样点128个样方的调查数据为基础,结合1960-1970年的研究资料,探讨了人为活动对滇池湖滨区高等植物种类的影响.结果表明: 2012年在滇池湖滨区共发现湿地高等植物88科299种,其中本土植物181种,外来植物118种(包括32种入侵物种);在42种水生植物中,13种为外来植物(包括2种入侵物种).与1960-1970年资料相比,新记录植物232种、已消失植物43种.其中,沉水植物、漂浮植物和浮叶植物分别减少了2种、2种和5种,挺水植物增加了8种.目前共有14个植物群落类型,新出现了以大薸、喜旱莲子草等外来植物为优势种的群落类型,而以海菜花、苦草等本土植物为优势种的植物群落已消失.在引种高等植物修复退化湖泊湿地时,应科学合理地选配植物物种,以免人工引发湿地退化.  相似文献   

14.
庐山外来植物物种   总被引:8,自引:0,他引:8  
生物入侵正日益成为普遍关注的生态环境问题.在庐山野外调查的基础上,再结合庐山植物引种记录资料的分析,发现庐山引入的2285种植物中,有1301种是室外栽培的,其中有127种82属35科逸为野生,成为庐山的外来物种.通过对这127种外来物种从物种组成、生活型、引入时间和方式、原生地和入侵性进一步分析,可以看出:外来物种主要由菊科、玄参科、禾本科、石竹科和苋科组成,这5科含种数占到总种数的63%;外来物种绝大多数为草本植物,含114种,占总种数的86.76%;原生地主要来源北美洲、其次是欧洲和亚洲,大部分是有意引进,引种目的主要用于观赏,其次是药用;在庐山127种外来物种中,有70种是列于中国100主要外来入侵物种,可见其入侵性还是很强.  相似文献   

15.
Current climate change has led to latitudinal and altitudinal range expansions of numerous species. During such range expansions, plant species are expected to experience changes in interactions with other organisms, especially with belowground biota that have a limited dispersal capacity. Nematodes form a key component of the belowground food web as they include bacterivores, fungivores, omnivores and root herbivores. However, their community composition under climate change‐driven intracontinental range‐expanding plants has been studied almost exclusively under controlled conditions, whereas little is known about actual patterns in the field. Here, we use novel molecular sequencing techniques combined with morphological quantification in order to examine nematode communities in the rhizospheres of four range‐expanding and four congeneric native species along a 2,000 km latitudinal transect from South‐Eastern to North‐Western Europe. We tested the hypotheses that latitudinal shifts in nematode community composition are stronger in range‐expanding plant species than in congeneric natives and that in their new range, range‐expanding plant species accumulate fewest root‐feeding nematodes. Our results show latitudinal variation in nematode community composition of both range expanders and native plant species, while operational taxonomic unit richness remained the same across ranges. Therefore, range‐expanding plant species face different nematode communities at higher latitudes, but this is also the case for widespread native plant species. Only one of the four range‐expanding plant species showed a stronger shift in nematode community composition than its congeneric native and accumulated fewer root‐feeding nematodes in its new range. We conclude that variation in nematode community composition with increasing latitude occurs for both range‐expanding and native plant species and that some range‐expanding plant species may become released from root‐feeding nematodes in the new range.  相似文献   

16.
3种入侵和本地沉水植物形态和生理性状对螺类牧食的响应 沉水植物水盾草(Cabomba caroliniana)已成为中国太湖流域的优势入侵水生植物。与外来物种的原产地环境相比,引入地新环境中存在的专食性天敌较少。外来物种可能会逃避其原产地环境中的天敌牧食,又因为它们的适口性相对较差,从而导致在引入地外来物种通常比本地物种遭受的牧食者影响更低(天敌逃逸假说)。本研究的目的是比较水盾草与共生的本地沉水植物对本地牧食者的响应。我们进行了一个中宇宙尺度实验,研究了水盾草和两种共生的本地沉水植物黑藻(Hydrilla verticillata)和穗花狐尾藻(Myriophyllum spicatum)对两种本地广食性腹足纲螺类萝卜螺(Radix swinhoei)和环棱螺(Sinotaia quadrata)的牧食响应。记录了它们的形态性状指标(总生物量、冠根比和相对生长率)和生理性状指标(叶片总非结构性碳、木质素和纤维素)。研究结果表明,环棱螺对3种沉水植物性状指标的影响较少。随着本地广食性螺类萝卜螺数量的增加,黑藻和穗花狐尾藻大部分植物性状发生了改变,而水盾草的植物性状表现出相对稳定的趋势。水盾草对萝卜螺的牧食更具抵抗力,这与天敌逃逸假说的假设一致。这一发现说明牧食性螺类促进了水盾草的入侵,这可能会改变沉水植物群落中的物种组成。  相似文献   

17.
1. Changes to plant community composition after invasion are well documented but how these shifts directly affect higher trophic levels is still poorly understood. One potentially important factor is the change in nutritional availability after an invasion. Shifts in nutrient availability could affect the nutrient intake of organisms that live in invaded habitats, causing reduced fecundity and survival. 2. The effects of the interaction among nutrient availability, selection, and diet on nutrient intake of a native bumble bee were examined. No nutritional differences were found between exotic and native pollen or collected and non‐collected pollen in protein or amino acid content, suggesting that differences in nutrient intake from random are based on selection. 3. Nutrient intake was simulated when pollen was selected randomly across all available plant species and when selection was restricted to native plants only or exotic plants only using a permutation model and compared with observed collection. The results suggest that pollen collection is non‐random and that selecting only native or exotic plants cannot provide the protein or amino acid intake observed. 4. These results may help to explain why the responses of native bees to exotic plants are so variable. If the exotic plants in a community can supply the necessary nutrients, bees may readily incorporate them into their diets, but if not, exotic plants may be avoided.  相似文献   

18.
Biological invasions represent a global threat to biodiversity. Particular attention should be devoted to the management of alien plants, focusing on the opportunity to obtain a rapid response to invasion and restoration of the invaded areas. In this study we aimed to evaluate five different methods for controlling Oxalis pes-caprae, a well-known invasive plant native to South Africa, also focusing on the restoration of the native flora. We set an experiment on the island of Montecristo (central Mediterranean). Treatment methods varied from chemical to low risk methods, including manual removal, covering with mulching sheets, and foliar spraying with acetic acid (30% solution) and two different concentrations of glyphosate (3 and 5% solutions, respectively). The total cover of O. pes-caprae and of other native plants was sampled before treatments, and then several times during the subsequent year; while the plant species composition was sampled in late winter (March 2015–2016) and late spring (May 2015–2016). The use of glyphosate was found to be the only efficient control method, leading to a significant decrease in O. pes-caprae cover as well as to a recovery in native species cover and richness. The effect of the other control methods was negligible.  相似文献   

19.
Invasive plants that displace native floral communities can cause changes to associated invertebrate species assemblages. Using a mini‐review of the literature and our own data we add to the still considerable debate about the most effective methods for testing community‐level impacts by invasive species. In endangered saltmarshes of southeast Australia, the non‐native rush Juncus acutus L. is displacing its native congener J. kraussii Hochst., with concurrent changes to floral and faunal assemblages. In two coastal saltmarshes, we tested the hypothesis that the ability to detect differences in the invertebrate assemblage associated with these congeneric rushes depends on the microhabitat of the plant sampled. We used three sampling methods, each targeting specific microhabitats: sweep netting of the plant stems, vacuum sampling of the plant tussock, and vacuum sampling of the ground directly below the plants. Over 3800 individuals and 92 morphospecies were collected across four main taxa: gastropods, crustaceans, hexapods and arachnids. Detection of differences in invertebrate density, richness and composition associated with native compared with non‐native rushes was dependent on the microhabitat sampled and these differences were spatially variable. For example, at one saltmarsh the stems and tussock of J. acutus had a lower density and richness of total invertebrates and hexapods than those of the native J. kraussii. In contrast, crustaceans on the ground were in greater abundance below J. acutus than J. kraussii. This study demonstrates that on occasions where overall differences in the assemblage are not detected between species, differences may become apparent when targeting different microhabitats of the plant. In addition, separately targeting multiple microhabitats likely leads to a greater probability of detecting impacts of invasion. Comparing the invertebrate assemblage without differentiating between or sampling an array of microhabitats can fail to determine the impact of invasive species. These results highlight that a combination of methods targeting different microhabitats is important for detecting differences within the invertebrate community, even for phylogenetically related species.  相似文献   

20.
基于2008—2012年对三峡水库奉节以东秭归和巫山段消落带固定样地不同海拔区段植物群落的5a定位监测,研究消落带植物群落的物种组成、优势植物、植物生活型和物种多样性的动态变化,结果表明:1)截止2012年,消落带海拔156—172 m区段共经历了4次水库水位涨落。经历首次后(2009年),消落带原生植物由55科147种减少到18科33种,经历4次后(2012年),减少到14科39种。与经历水库水位涨落前(2008年)比较,经历首次后的科数减少了67.3%,种数减少了77.6%;经历4次后的科数减少了74.5%,种数减少了73.5%。在消落带原生植物减少的同时,出现了许多"新"植物。经历首次后出现了49种,经历4次后出现了23种,分别占调查当年样地植物种类总数的59.8%和32.9%。海拔172—175 m区段共经历了2次水库水位涨落,消落带原生植物由40科91种(2008年)减少到了13科20种。与经历水库水位涨落前比较,科数减少了67.5%,种数减少了78.0%。出现"新"植物21种,约占调查当年样地植物种类总数的44.7%。通过对历次调查中消落带植物"消失"和"出现"的数量比较表明,消落带植物对经历首次水库水位涨落的反应最为敏感,此后,虽又经历过几次水库水位涨落,但其变化速率趋于减小。2)不同海拔区段、不同生态适应型植物的"消长"动态和优势种组成不完全相同。海拔156—172 m区段,经历4次水库水位涨落后,在消落带植物群落中占优势的草本植物种为菊科(Compositae)的鬼针草(Bidens pilosa)、禾本科(Gramineae)的狗牙根(Cynodon dactylon)、毛马唐(Digitaria chrysoblephara)、狗尾草(Setaria viridis)、莎草科(Cyperaceae)的碎米莎草(Cyperus iria),占优势的灌木树种为漆树科(Anacardiaceae)的盐肤木(Rhus chinensis)和大戟科(Euphorbiaceae)的算盘子(Glochidion puberum);在海拔172—175 m区段,除鬼针草、毛马唐仍为优势种外,还增加了大戟科的湖北算盘子(Glochidion wilsonii),马鞭草科(Verbenaceae)的黄荆(Vitex negundo),葡萄科(Vitaceae)的五叶地锦(Parthenocissus quniquefolia)等树种。3)消落带植物群落的优势生活型为一年生和多年生草本;物种多样性随着水库水位涨落次数的增加总体变化呈减少趋势。4)三峡水库水位周期性涨落导致消落带发生水陆环境交替变化,不同生态适应型植物对变化生境的适应能力有所不同,是消落带植物群落发生变化的主要驱动因素。  相似文献   

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