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河道堤防是防止河流下游洪水漫溢的屏障。在河道堤防造林可以起到保持水土、加固堤防的作用，还能够形成河堤景观，丰富人民的精神和文化需求。因此，在河道治理及管理过程中，政府对河道堤防造林越来越重视。作者在经过深入考察和调研的基础上，详述了河道堤防造林的积极作用，讲述了河道堤防造林前的准备工作、苗木供应、监管苗木、造林现场管理和内业及档案管理具体策略，对今后河道造林及管理工作以及如何提升造林效果提出了自己的见解。 相似文献
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1998年之夏,长江流域发生了特大洪水,武汉关危险水位持续了46天,8次洪峰汹涌奔泻,肆虐地冲击着两岸的一切。素有武汉市长江堤防重点险段之一的武昌月亮湾堤段,新近建成的堤防坚如钢铁长城,使险段化夷。然而,更引人注目的是,堤内外护坡绿色如带,花草繁茂,迎风摇曳,保护和美化着堤防。堤外一座红顶白柱的六角亭和古铜色正扬蹄奋进的水牛雕塑,犹若江中砥柱,见证了这场汹猛的洪水,也 相似文献
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去冬今春,湖北省江河堤防植树已突破500万株,截止目前,境内2625公里的长江、汉江及东荆河堤防存量树木已达3200万株,种草近2000万平方米,并逐步探索出“以林(草)护堤,以林(草)养堤”的良性循环发展之路。湖北省仅江河干堤、重要之堤就长达7050公里。1998年,长江流域发生百年不 遇的特大洪水后,党中央、国务院及时决策,投入巨资进行了堤防建设。然而在大规模堤防建设中,人们却忽视了保护堤防林草。1999年汛期,长江堤防“赤膊”上阵,险象丛生。为确保大堤安全,沿江各级政府、堤防管理部门下决心迅速重造沿江沿河绿色长廊。在湖北省省委、省政府的高度重视下,堤防管理部门有计划地加大了全省堤防植树种草投入力度,堤防建成一段,植树种草就完成一段。他们引入堤防建设管理体制,对堤防植树造林实行公开招标、质量监理和合同管理。同时通过落实土权、林权、管理权,促进防护林栽好、管好和长好,使千里林带更好地发挥防洪、生态、观赏及经济效益。武汉市将堤防绿化与城市环境改造相结合,在全市种植意杨、水杉、速生柳等防浪、护堤林达210万株,种草180万平方米,新植棕榈、黄杨球、冬青、垂柳、腊梅、樟树等多种观赏林木... 相似文献
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一、防浪林的作用长江堤防工程,在目前防洪工程中,占着最重要的地位。长江汉水中下游的干堤,绵长约有5,000余公里,另有若干湖堤圩堤,保护着沿江沿湖约35,000平方公里内的地区。这些堤防工程,主要是用土料堆築,洪水期间风吹浪打,损害甚大,对于防浪护 相似文献
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随着社会经济的发展,园林植物的生态效益、经济效益、观赏效益日益凸现。与此同时园林植物虫害出现了复杂化、危险化的趋势,对绿地和风景区危害较大。笔者从害虫来源、防治等角度出发,介绍了植物检疫的概念和方法,提出了园林植物害虫防治技术,主要包括:园林植物管理、生物防治、物理机械防治、化学防治等措施,以期为园林植物害虫的防治,园林绿地质量的提高提供参考。 相似文献
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植物化感作用机理及其在园林植物配置中的应用 总被引：3，自引：0，他引：3
园林植物化感作用的研究对于园林植物配置的科学性和植物群落演替有着直接影响,同时也影响园林人工生态系统的稳定和功能发挥。通过分析园林植物的化感作用及其机理,阐述了植物化感作用在园林植物配置中的应用形式,指出了园林植物配置中利用植物化感作用,合理进行植物配置具有经济、生态等各方面的效益,能在一定程度上解决园林植物的可持续发展问题,为园林设计者提供了新的研究方向,有助于提高我国园林植物配置水平。 相似文献
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北京城区园林植物生物量的计测研究 总被引：2，自引：0，他引：2
采用平均标准木法,使用全砍称鲜重和干重,对北京城区园林植物主要类型和主要树种的平均生物量进行了研究。鉴于园林植物绿化普查中对植物种类和类型分类的特殊性和复杂性,利用绿化普查资料测算出了北京城区现有园林植物的总生物量。北京市现有园林植物总生物量181.86万t,城八区为129.12万t。为园林植物的生态功能研究以及相关的生态环境评价等提供了基础依据。 相似文献
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选取北京市具有代表性的药用植物专类园作为调查地点,进行药用植物种类及应用情况调查,得知应用的药用价值较高种类共316种,隶属于81科228属,其中乔灌木74种,藤本植物22种,水生植物8种,其他草本植物212种。此外,园中还配植了一些以观赏为主的种类,有乔灌木32种,草本11种。作者对其植物配植亮点进行了点评,并就存在的问题提出了建议。 相似文献
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为了提升沧州市公园绿地植物群落的生态功能和植物景观效果,选择5个具有代表性的公园绿地作为研究对象,对其中应用植物的种类、生活型等进行调查,并构建植物群落景观综合评价体系,采用层次分析法(AHP)对选取的67个植物群落进行综合评价。结果表明,沧州市公园绿地应用的植物种类共计239种,隶属66科145属,其中乔木103种、灌木61种、草本51种、水生植物11种、藤本7种、竹类6种,灌木、草本、常绿植物、水生植物等应用较少;植物群落景观质量整体良好,Ⅰ级和Ⅱ级植物群落景观共52个,但优质植物群落景观相对较少,仅有4个Ⅰ级植物群落景观;根据存在的具体问题,提出增加灌木、草本及常绿植物的种类和数量,丰富植物群落层次,结合植物的季相变化、观赏特性及生态习性进行合理配置,加强对植物的后期养护管理等措施。 相似文献
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Comparison of fractal characteristics of species richness patterns among different plant taxonomic groups along an altitudinal gradient 总被引：1，自引：0，他引：1
This study was done using the non brown fractal model to quantify and compare the variations in the species richness of trees,
shrubs, herbs and all plants along an altitudinal gradient and to characterize the dominating ecological processes that determine
the variations.
Two transects were sampled far away from any anthropogenic disturbances along the shady slopes of the Dongling mountains in
Beijing, China. Both transects were continuous and 2 m wide, and every individual tree and shrub was recorded in each of them.
Discrete quadrats of 1 m × 1 m were located along the transects A and B for estimation of the herb species richness along
the altitudinal gradients. The level interval between the quadrats was 10 m and 25 m respectively. In this study, transects
A and B were combined into one transect AB, and 40 m was selected as the optimal quadrat length along the altitudinal gradients
for measuring the plant species richness patterns. Species richness in each quadrat was calculated using a program written
in Matlab 6.0.
Direct gradient analysis was used to describe the overall trends in the species richness of trees, shrubs, herbs and other
plants with change in altitude, while the non-brown fractal model was used to detect more accurately their variations at various
scales along the gradient. The model assumed that each class of ecological processes affecting the distribution of a variable
could be represented by an independent spatial random function. Generally, ecological phenomena are determined not by a single
ecological process but by multiple ones. These processes act on ecological patterns within their own spatial scales. In the
non-brown fractal model, the spatial random functions are nested within a larger range of spatial scales. The relative contribution
of the spatial random functions to the spatial variation of a variable is indicated by a weighting parameter that has to be
greater than or equal to zero.
In this paper, we reached the following results and conclusions. Firstly, the direct gradient method describes the general
trends of trees, shrubs, herbs and all plants along the altitudinal gradient but is unable to provide further details on the
altitudinal variations in the species richness. The non-brown fractal model brought out the altitudinal variations in the
species richness of trees, shrubs and herbs at various scales and related them to the ecological processes. The sharp changes
in the double-log variograms suggest that the non-brown fractal model is suitable for characterizing the altitudinal patterns
in the species richness of trees, shrubs and herbs at various scales but is not appropriate for explaining the variations
in the plant species richness, since no significant changes were found in the double-log variograms in this case. Secondly,
for the trees, the double-log variogram was divided into two scale ranges (0–245 m and 245–570 m), with a fractal dimension
of 1.83 and 1.10, respectively, implying that changes in the tree species richness were random at small scales (0–245 m) and
almost linear at large scales (245–570 m) along the altitudinal gradients. This suggests that altitudinal variations in the
tree species richness are dominated by short-range processes at small scales and by long-range processes at large scales.
Thirdly, for shrubs and herbs, the double-log variograms exhibited three ranges (0–101 m, 125–298 m and 325–570 m), and the
fractal dimensions were 1.78 and 1.97, 1.56 and 1.43, and 1.08 and 1.25, respectively. The results indicate that, as in the
case of trees, species richness of shrubs and herbs are distributed randomly at small scales and change in a linear manner
at large scales although variations in the herb species richness is less heterogeneous than shrub species richness at large
scales. These results also indicate that species richness of shrubs and herbs change approximately like brown movement at
middle scales. The results also suggest that altitudinal variations in the specie richness of shrubs and herbs are dominated
by three ecological processes, short-range ecological processes at small scales, long-range ecological processes at large
scales, and brown fractal processes at middle scales. Interestingly, comparisons of the variations in the species richness
of shrubs and herbs reveal that shrubs and herbs present the same scale range in spatial variation in species richness but
display different trends in species richness along the altitudinal gradient, i.e. the shrub species richness decreased with
increasing elevation whereas the herb species richness peaked at the mid-high elevation. These patterns suggest that although
the scales at which the main processes affect patterns in species richness are the same, the processes are completely different,
or the processes are similar but the responses of the shrubs and herbs to the ecological processes are different. Finally,
the plant species richness did not show any obvious pattern along the altitude gradient and maintained a constant fractal
dimension across all scales, this is perhaps because the processes defining the patterns of plant species richness had similar
weights and acted over closely related scales.
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Translated from Acta Phytoecologica Sinica, 2005, 29(6): 901–909 [译自: 植物生态学报] 相似文献
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次生林火后演替过程中物种变化及相互关系 总被引：2，自引：0，他引：2
采用植被空间序列代替时间系列的研究方法,分析黑河地区近20 a来不同重度火烧迹地上植被的演替变化。研究表明：火后初期,草本、灌木迅速占据火烧迹地,灌木在数量和盖度上不及草本,随着火烧年度的推移,草本、灌木在数量和盖度上逐渐减少,物种结构也发生了很大的变化,乔木在数量和盖度上呈上升趋势。研究发现,灌木、草本高频物种所占比例较高且呈上升趋势,灌木高频物种高于草本的高频物种。另外还发现不同火烧迹地上灌木物种的相似度高于草本物种相似度,相似度范围波动较大,火烧迹地上相邻年份物种的相似度高于年份相差久远物种的相似度。 相似文献
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以南京森林警察学院仙林校区为研究对象,对该校区校园内的植物种类进行了调查分析。结果表明,校区内共有植物215种,隶属于79个科,其中以蔷薇科、木兰科、菊科等少数儿个科占有较多的种类。对校区内的乔木层、灌木层和地被植物进行了分析,指出了各层次的物种搭配存在的问题,并分析了校园森林群落的季相变化。出于教学的需求,提出了引种... 相似文献
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大规模的水利、交通、矿山等工程建设,给自然界留下了大量裸露的边坡,导致生态环境恶化。通过对朝阳燕山湖发电厂厂区边坡生态防护和分析,打破以往生态防护的主体是豆科、禾本科等草本植物,着重研究灌木类木本植物在生态防护中的优势,论述了灌木在边坡生态防护中的作用。 相似文献
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长白山区主要野生饮料植物资源 总被引：9，自引：0，他引：9
长白山区主要野生饮料植物共有14科、28属、54种。其中乔木类：3科、7属、17种；灌木类：4科、10属、20种；木质藤本类：3科、3属、5种；多年生草本类：7科、8属、11种；1，2年生草本类：1科、1属、1种。同时还介绍了主要野生饮料植物在5个不同景观带的分布情况，提出了开发利用和保护的具体建议。 相似文献
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The effects of microhabitat (shrubs and herbs), plant litter, and seed burial on the regeneration of Liaodong oak (Quercus wutaishanica Mayr) and Chinese pine (Pinus tabulaeformis Carr.) were studied in three typical stands (Liaodong oak forest, Chinese pine plantation, and grassland) in the Loess Plateau, China. We monitored the establishment and growth of seedlings of these two woody species in sown experimental plots, in which shrubs and herbs, plant litter, and seed burial were manipulated. In the grassland, shrubs and herbs facilitated Liaodong oak establishment, with no effect on the establishment of Chinese pine. In the two forest stands, shrubs and herbs primarily had an inhibition effect on the establishment of these trees. The effects of plant litter were facilitation or inhibition, depending on the target species and the habitat. Seed burial had a positive effect on seedling establishment. In all three habitats, shrubs and herbs had inhibition effects on seedling growth of both tree species. Plant litter and seed burial did not influence seedling growth in either species. Liaodong oak and Chinese pine use different regeneration strategies during early stages of succession and similar strategies during late stages of succession. 相似文献