福建福诏高速公路景观绿化植物种类调查

对福建福诏高速公路景观绿化24个样点的植物种类进行调查。结果表明,本段景观绿化植物种类有92种(乔木32种,灌木地被49种,竹类3种,藤本4种,草皮4种),分属39科;主要由观花植物(35%),观叶造型植物(25%)和棕榈植物(25%)组成,具有显著的热带、亚热带风光景观效果。     

层次分析法在粤北高速公路沿线绿化树种选择中的运用

以广东省仁化至博罗高速公路(仁化至新丰段路)为例,通过对该路段沿线乡土植物调查,运用层次分析法(AHP)对388种乡土植物的环境适应性、培植特性、功能特性和经济效应进行评价和综合分析。结果表明,在一级指标中,环境适应性权重最大(0.5476);其次是功能特性(0.2051)。在选取的14个二级指标中, 耐贫瘠权重最大(0.1642),耐旱能力和耐寒性的权重相对也比较大,分别为0.1533、0.0916。根据AHP模型,对所调查的388种乡土植物进行评价,其中评分80分以上适宜高速公路绿化的有64种。结合观赏性、耐寒性评价和市场苗木供应情况最终筛选出20种乡土植物作为仁新高速沿线绿化的建议树种。     

基于AHP法黑龙江多宝山铜业矿山排土场植物筛选

以黑龙江多宝山铜业矿山排土场边坡植被恢复和景观重建的植被筛选为目的,在对矿区本底植物调查、黑龙江省栽培植物调查的基础上,运用层次分析法(analytic hierarchy process,AHP)构建生态适应性、生态防护性、绿化效果、经济性4个方面10个具体指标的筛选评价体系,对74种植物进行权重排序,最终筛选出适用于多宝山铜业矿山排土场植被修复的乔木、灌木、草本共计20种,为矿山排土场生态环境的改善和景观重建提供了植物选择,也为我国寒区其他矿山排土场生态修复植物的选择提供一些实践借鉴。     

高速公路绿化设计及植物选择探讨

近年来,随着我国社会经济的快速发展和交通建设事业的不断进步,高速公路工程项目建设发展非常的迅速。高速公路安全性、可靠性以及舒适性不断提高的同时,也对高速公路绿化设计以及植物的配置提出了更高的要求。本文将对高速公路绿化设计功能及设计原则进行分析研究,并在此基础上就如何有效的选择绿化植物,谈一下自己的观点和认识,以参考。     

老界岭自然保护区观赏植物资源及其在园林中的应用

通过大量的调查、标本采集鉴定,基本摸清了河南省老界岭自然保护区的植物资源。根据植物的特性和城市园林绿化对植物的要求,初步筛选了本区１１８５种植物作为绿化观赏植物,并根据它们在城市园林绿化中的作用将其进行了分类和评述。最后就自然保护区野生观赏植物的合理利用等问题,提出了一些建议．     

厦门引种的榕属植物资源及其园林应用

对厦门榕属植物资源的调查发现,该地区引种栽培的榕属植物约67种,榕属植物在厦门城市绿化中的作用十分显著。对城区131条道路绿化的调查表明,大叶榕和高山榕为骨干绿化树种,重要值均在6%以上。     

苏南乡村生态植物景观营造

乡村生态植物景观营造是乡村景观建设的重要内容。本文以模拟自然、半自然植物群落为基础,对乡村生态植物景观营造进行了研究。根据乡村景观的构成要素,可以将乡村植物景观划分为村落植物景观(农户外环境植物景观)、农田植物景观、道路植物景观和水域河道植物景观;生态植物景观营造可以从自然群落中得到借鉴,以常熟为例,采用植被生态学的调查和分析方法对当地自然、半自然植物群落进行了研究,模拟形成15个可供当地应用的人工配植模式;乡村不同植物景观类型具有各自的特色和功能要求,通过分析常熟典型乡村特点,以模拟自然群落为基础,可进一步改造形成适于不同类型的乡村植物景观配植模式。     

石鼓书院植物景观资源评价与保护

石鼓书院共有植物29科31属41种,主要植物景观类型5种.文章对评价指标进行量化,建立了植物景观评价指标体系,采用植物景观综合评价指数法和AHP法对石鼓书院槙物景观进行评价与分析.认为其植物景观资源整体水平偏低,植物景现质量为IIl级;对石鼓书院的植物景观恢复和保护提出了可行性建议.     

徐州城市景观格局对绿地植物多样性的多尺度影响

城市地表景观的变化导致城市生物栖息地的损坏、破碎和丧失,致使城市生物多样性下降.为探讨城市景观格局变化对植物多样性的影响,本研究以徐州市绕城高速公路内的城区为对象,采用布朗布伦奎特(Braun-Blanquet)盖度等级法对36块城市绿地植物群落进行调查,并对不同绿地植物群落的物种多样性进行了分析.同时,以研究区2005和2015年的Landsat ETM遥感影像作为基础数据源,在Erdas、GIS、Fragstats软件的支持下,以每块调查样地为中心,分别建立9个不同半径的缓冲区,计算各缓冲区内表征斑块形状、破碎度和连通性共3类39个景观指数,在此基础上,运用冗余分析(RDA)筛选出不同幅度下对城市绿地植物多样性有显著影响的景观格局指数.结果表明: 植物多样性对景观整体格局和景观要素的响应具有明显的时间和空间尺度效应.2005年,未利用地和农田的破碎度、形状指数在800 m半径的缓冲区内能更好地解释植物多样性,建筑用地的破碎度和连通性指数在800～2000 m范围内对植物多样性有重要影响;2015年,草地和林地景观在800 m缓冲区内可更好地解释植物多样性,而建筑用地和未利用地在1000～2000 m范围内对植物多样性有显著影响;研究区当前植物多样性受2005年类型水平景观指数的影响更显著,说明研究区植物多样性对周边景观格局变化的响应存在一定的时间滞后;景观水平的格局指数与类型水平指数特征较为一致,说明物种与空间尺度的相互作用更多依赖于景观类型.     

宜昌城区绿地景观格局与大气污染的关系

在湖北省宜昌市中心城区4种景观绿地分布格局分析的基础上,对比观测了各景观中的环境噪声和大气SO2、NOx、TSP含量。结果表明,以无绿化道路廊道和建筑铺装斑块为主要景观构成的对照景观绿地破碎化指数最高(18．1253ind·hm^-2),绿化覆盖率仅为1．00％,其景观中环境噪声较大、大气TSP含量高(0．4918mg·m^-3);大面积绿地斑块占优势的景观绿化覆盖率高(达43．59％),绿地破碎度指数最小(0．4539 ind·hm^-2),与对照景观相比,大气噪声减弱28．12％,TSP含量降低86．42％;中小面积绿地斑块和绿化廊道呈均匀分布的景观绿化覆盖率(11．34％)和绿地破碎度指数(2．7511 ind·hm^-2)均较低,与对照景观相比平均滞尘率为46．62％;以绿化廊道占绝对优势的景观绿化覆盖率仅为6．13％,绿地破碎度指数均较高(6．8700 ind·hm^-2),绿化廊道密度指数最大(0．8443hm·hm^-2),其景观中环境噪声、TSP和NOx含量分别比对照景观增加21．47％、5．08％和9．06％.可见,在城市景观中绿地斑块平均面积越大、破碎度指数越低,则其对大气污染净化的作用越大。     

大保高速公路老营段路域植被生态恢复

路域植被生态系统的恢复与重建不仅是道路生态学的重要研究内容,而且也是恢复生态学的重要研究领域.以大保高速公路老营段路域植被生态系统为对象,对比分析了8种植被恢复模式的作用效果与作用机理.研究结果表明,在相同的恢复时间内,自然恢复的植物群落中本土植物的比例相对较高,自然恢复是该区路域植被恢复的理想模式之一.随着恢复演替时间的推移,所有群落中木本植物的比例不断增加,草本植物的比例不断下降,植物群落分层现象明显,植物群落向原生植被发生进展或偏途演替.补播本土植物是促进植被恢复演替进程的主要途径之一,不仅可以增加乡土物种的比例、增加植物群落的多样性和均匀度,而且随着恢复时间的推移,可以形成层次明显、功能群组合合理的植物群落.人工蓝桉经济林不仅降低了植物群落及各功能群的多样性、丰富度和均匀度,而且在一定程度上增加了潜在生态风险.研究结果还表明,植物群落中当地物种的比例、植物群落的物种多样性和植物群落的盖度可以作为植被恢复成功与否的重要判定指标.     

中山市小榄镇城区绿地植物调查与评价

本文对小榄镇城区绿地植物种类进行了调查与研究.调查发现,小榄镇植物种类丰富,有105科433种.其中,公园绿地和苗圃区植物种类最多,街头与街道附属绿地植物种类较单调:乔木与灌木应用较多,藤本植物应用较少:乔木花卉于公园中应用较多;人工造林的林相、林型单一.旧城区绿地严重缺乏;部分工厂、学校对绿化不重视.研究提出,合理选择绿化树种,将木兰科植物作为乡土类的重点,紫葳科、木棉科和豆科作为外来树种引进的重点;对贺榄山现存桉树、相思疏残林进行林相改造,选择樟科、壳斗科、山茶科等作为骨干树种分期、分批进行混植.最后,筛选出适合各种类型绿地应用的绿化树种.     

常色叶类树木在四川的应用现状与发展对策

常色叶类树木是近年来出现的园林绿化新材料,大力发展常色叶类树木对园林植物景观类型的丰富以及植物景观营造的方式方法的改进和提高具有很重要的意义。通过对四川园林植物中常见的常色叶类树木种类和配置方式的调查和现状分析,对如何更好地发展四川常色叶类树木提出了几点建议。     

Plants, insects and birds in semi-natural pastures in relation to local habitat and landscape factors

The preservation of remaining semi-natural grasslands in Europe has a high conservation priority. Previously, the effects of artificial fertilisation and grazing intensity on grassland animal and plant taxa have been extensively investigated. In contrast, little is known of the effects of tree and shrub cover within semi-natural grasslands and composition of habitats in the surrounding landscape on grassland taxa. We evaluated the effect that each of these factors has on species richness and community structure of vascular plants, butterflies, bumble bees, ground beetles, dung beetles and birds surveyed simultaneously in 31 semi-natural pastures in a farmland landscape in south-central Sweden. Partial correlation analyses showed that increasing proportion of the pasture area covered by shrubs and trees had a positive effect on species richness on most taxa. Furthermore, species richness of nectar seeking butterflies and bumble bees were negatively associated with grazing intensity as reflected by grass height. At the landscape level, species richness of all taxa decreased (butterflies and birds significantly so) with increasing proportion of urban elements in a 1-km² landscape area centred on each pasture, while the number of plant and bird species were lower in landscapes with large proportion of arable fields. Our results differed markedly depending on whether the focus was on species richness or community structure. Canonical correspondence analyses (CCA) showed that the abundance of most taxa was ordered along a gradient describing tree cover within pastures and proportion of arable fields in the landscape. However, subsets of grassland birds and vascular plants, respectively, showed markedly different distribution patterns along axis one of the CCA. In contrast to current conservation policy of semi-natural pastures in Sweden, our results strongly advise against using a single-taxon approach (i.e., grassland vascular plants) to design management and conservation actions in semi-natural pastures. Careful consideration of conservation values linked to the tree and shrub layers in grasslands should always precede decisions to remove trees and shrubs on the grounds of promoting richness of vascular plants confined to semi-natural grasslands. Finally, the importance of landscape composition for mobile organisms such as birds entails that management activities should focus on the wider countryside and not exclusively on single pastures.     

The chloroplast genome sequence of Chara vulgaris sheds new light into the closest green algal relatives of land plants

The phylum Streptophyta comprises all land plants and six monophyletic groups of charophycean green algae (Mesostigmatales, Chlorokybales, Klebsormidiales, Zygnematales, Coleochaetales, and Charales). Phylogenetic analyses of four genes encoded in three cellular compartments suggest that the Charales are sister to land plants and that charophycean green algae evolved progressively toward an increasing cellular complexity. To validate this phylogenetic hypothesis and to understand how and when the highly conservative pattern displayed by land plant chloroplast DNAs (cpDNAs) originated in the Streptophyta, we have determined the complete chloroplast genome sequence (184,933 bp) of a representative of the Charales, Chara vulgaris, and compared this genome to those of Mesostigma (Mesostigmatales), Chlorokybus (Chlorokybales), Staurastrum and Zygnema (Zygnematales), Chaetosphaeridium (Coleochaetales), and selected land plants. The phylogenies we inferred from 76 cpDNA-encoded proteins and genes using various methods favor the hypothesis that the Charales diverged before the Coleochaetales and Zygnematales. The Zygnematales were identified as sister to land plants in the best tree topology (T1), whereas Chaetosphaeridium (T2) or a clade uniting the Zygnematales and Chaetosphaeridium (T3) occupied this position in alternative topologies. Chara remained at the same basal position in trees including more land plant taxa and inferred from 56 proteins/genes. Phylogenetic inference from gene order data yielded two most parsimonious trees displaying the T1 and T3 topologies. Analyses of additional structural cpDNA features (gene order, gene content, intron content, and indels in coding regions) provided better support for T1 than for the topology of the above-mentioned four-gene tree. Our structural analyses also revealed that many of the features conserved in land plant cpDNAs were inherited from their green algal ancestors. The intron content data predicted that at least 15 of the 21 land plant group II introns were gained early during the evolution of streptophytes and that a single intron was acquired during the transition from charophycean green algae to land plants. Analyses of genome rearrangements based on inversions predicted no alteration in gene order during the transition from charophycean green algae to land plants.     

Impact of habitat structure and fruit abundance on avian seed dispersal and fruit predation

So far, it is poorly understood how differential responses of avian seed dispersers and fruit predators to changes in habitat structure and fruit abundance along land-use gradients may translate into consequences for the seed dispersal of associated plants. We selected a gradient of habitat modification (forest, semi-natural, and rural habitat) characterized by decreasing tree cover and a high variation in local fruit availability. Along this gradient we quantified fruit removal by avian seed dispersers and fruit predators from 18 Sorbus aucuparia trees. We analyzed the relative importance of tree cover and fruit abundance in explaining species richness, abundance and fruit removal rates of both guilds from S. aucuparia trees. Species richness and abundance of seed dispersers decreased with decreasing tree cover, whereas fruit removal by seed dispersers decreased with decreasing fruit abundance independent of tree cover. Both variables had no effect on species richness, abundance and fruit removal by fruit predators. Consequently, seed dispersers dominated relative fruit removal in fruit-rich sites but the dispersal/predation ratio shifted in favor of predation in fruit-poor habitat patches. Our study demonstrates that variation in local habitat structure and fruit abundance can cause guild-specific responses. Such responses may result in a shift in fruit removal regimes and might affect the dispersal ability of dependent fruiting plants. Future studies should aim at possible consequences for plant recruitment and guild-specific responses of frugivores to disturbance gradients on the level of entire plant–frugivore associations.     

北京城区公园的植物种类构成及空间结构

对植物种类构成及空间结构的研究,可为公园植物多样性保护及公园的科学管理提供重要依据.采用分层随机抽样调查法,调查了北京市五环以内的53处公园,共记录维管束植物96科283属492种.基于研究区乔、灌、草共21个调查项目的大量数据及相关统计分析,对北京城区公园绿地各层植物的常见结构型式进行了阐述.结果表明：北京城区公园植物中,本地种占5386%,植物属的区系地理分布很广泛,优势植物的优势性明显;研究区大部分公园的草本植物种类较为丰富、盖度较高,而灌木盖度偏低、树冠下的灌木也偏少,乔灌植物种类丰富度和密度不高,乔木冠幅、胸径、灌幅及乔灌高度基本在2级水平,但乔木冠层结构比较丰满、受光良好、生长状况良好,灌木叶层缺失不明显.通过相关分析和北京市园林绿化史调研结果推测,北京城区公园植物种类构成及其空间结构主要受园林设计、植物引种、种植管理的影响.     

Floristic inventory of wild plants of Peshawar university campus

Floristic inventory of wild plants comprised of total 129 plant species belonging to 42 families and 101 genera. Location wise UAP contributed greater amount of plant species (53%), followed by PFI (29%), UoP (15%) and Islamia College (3%). Majority of the plants were annual herbs (58%), followed by perennial herbs (29%), trees (10%) and shrubs (3%), respectively. The leading families included Poaceae, contributed 18% of all the plant species. Habitat wise, 44% of them grew in grassy plains, abandoned lands and mismanaged lawns, followed by roadsides (34%), undulating grassy plains (15%) and stony grounds with uneven topography along with stream banks and drainage ditches (7%). Still some of plant species were used as ornamentals, while some shrubs were use in fencing around fields; others were utilized as green manure, for fishing, sheltering and religious purposes. Exploring and identifying the wild flora of the campus and compiling as a handbook would help to monitor new plants introductions particularly of noxious invasive weeds in the campuses in future.     

Body size distribution in aphids: relative surface area of specific plant structures

Abstract.

• 1 The distribution of the body sizes of British aphids is right-skewed on a logarithmic axis, as in other taxa. Over the size range 2–5 mm there is a marked decrease in numbers of species with increase in size, which on a log log scale has an exponent of -3, The exponent for the right-hand side of the size distribution of British plants is -0.7.
• 2 The sizes of sixty-eight species of the genus Aphis are weakly correlated with the size of their respective host plants.
• 3 An aphid's size is strongly correlated with the length of its proboscis, which indicates the depth to which it has to probe plant tissues in order to feed.
• 4 On average, trees host more species of aphids than either shrubs or herbaceous plants, which appears to be associated with the relative surface area of specific plant structures. The surface area of plants is mainly made of leaves and most species of aphids are leaf feeders. The largest and least numerous species of aphids feed on the branches and trunks of trees, the proportional cover of which is less than that of leaves.
• 5 Taking into account all the above observations, a functional explanation in terms of the relative surface area of specific plant structures is offered to account for the size diversity curve of aphids.

     

Savannas after afforestation: Assessment of herbaceous community responses to wildfire versus native tree planting

Afforestation and fire exclusion are pervasive threats to tropical savannas. In Brazil, laws limiting prescribed burning hinder the study of fire in the restoration of Cerrado plant communities. We took advantage of a 2017 wildfire to evaluate the potential for tree cutting and fire to promote the passive restoration of savanna herbaceous plant communities after destruction by exotic tree plantations. We sampled a burned pine plantation (Burned Plantation); a former plantation that was harvested and burned (Harvested & Burned); an unburned former plantation that was harvested, planted with native trees, and treated with herbicide to control invasive grasses (Native Tree Planting); and two old-growth savannas which served as reference communities. Our results confirm that herbaceous plant communities on post-afforestation sites are very different from old-growth savannas. Among post-afforestation sites, Harvested & Burned herbaceous communities were modestly more similar in composition to old-growth savannas, had slightly higher richness of savanna plants (3.8 species per 50-m²), and supported the greatest cover of native herbaceous plants (56%). These positive trends in herbaceous community recovery would be missed in assessments of tree cover: whereas canopy cover in the Harvested & Burned site was 6% (less than typical of savannas of the Cerrado), the Burned Plantation and Native Tree Planting supported 34% and 19% cover, respectively. By focusing on savanna herbaceous plants, these results highlight that tree cutting and fire, not simply tree planting and fire exclusion, should receive greater attention in efforts to restore savannas of the Cerrado.