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1.
混播构建野花组合景观时,其不同植物种间竞争与共存问题是植物景观形态与质量可持续性营造的理论依据。现以赛菊芋(Heliopsis helianthoides)、宿根亚麻(Linum perenne)、蓝蓟(Echium vulgare)3种植物为例,采用露地直播的方法,设置3种植物单独播种和混合播种2种播种模式(3种材料单独播种CKY、CKM、CKJ,T1处理宿根亚麻和赛菊芋1∶1混播,T2处理宿根亚麻和蓝蓟1∶1混播,T3处理赛菊芋和蓝蓟1∶1混播,T4处理宿根亚麻、赛菊芋和蓝蓟1∶1∶1混播),对不同播种模式下3种植物的株高生长量、相对生物量(RY)、相对密度(RD)、竞争率(CR)和相对产量总值(RYT)进行分析,研究了3种供试植物在等比例混播中的竞争关系与共存问题,及构建野花组合植物景观过程中的竞争关系与共存机制。结果表明:3种植物混播中竞争力表现为蓝蓟赛菊芋宿根亚麻。其中与宿根亚麻的混播促进了赛菊芋的生长,与其它植物的混播均对宿根亚麻的生长产生了抑制作用而对蓝蓟无显著的影响。在等比例混播的条件下,T1、T2、T3、T4处理均不具备混播花卉植物群落的稳定性,将3种植物应用于混播植物景观时应适当降低蓝蓟的混播比例,而提高宿根亚麻的混播比例,从而保证第2年景观的可持续性并提高植物群落稳定性。 相似文献
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白三叶与红三叶是豆科多年生草本植物，具有绿期长、较耐修剪、观赏价值高、营养价值丰富等特点。为更好地利用2种草坪草建植草坪，对三叶草属中白三叶与红三叶种子出苗和幼苗生长阶段的种内与种间关系进行了比较分析。结果显示，在种子出苗阶段不同组合方式下，红三叶的出苗率高于白三叶，但差异不显著。幼苗阶段不同组合方式下，红三叶的生长指标均显著大于白三叶，由此可推断红三叶幼苗生长能力显著高于白三叶。无论单播建坪还是混播建坪，红三叶都更容易形成较好的草坪景观。在2种草坪草混播建坪时发现，白三叶与红三叶比例组合为2︰1时建坪效果最好，比例组合为1︰1时建坪效果次之。 相似文献
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植被在边坡生态系统中有着非常重要的作用,具有涵养水源、保持水土的功能.选择四川省成昆铁路沿线不同坡向的土质路堑边坡和岩质路堑边坡,对边坡植物群落的植被类型及其结构特征、边坡植被恢复物种组成及其特征进行了调查研究.结果表明:铁路边坡自然定居物种共103种,隶属48科,全部植物中,常绿灌木2种,落叶灌木9种,藤本植物7种,1 a生草本20种,2 a或2 a以上草本植物49种;蕨类植物15种.群落物种的丰富度虽然较高,但是主要由草本植物构成,结构层次简单,应该适当的在边坡上栽植灌木或小乔木,形成坡面上乔、灌、草或草、灌相互映的群落景观. 相似文献
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针对沈阳地区的气候及立地条件建立了3种混播组合模式,并运用了层次分析法(AHP)对其应用进行了评价,旨在为草花混播在沈阳地区的推广提供技术参考.结果表明:22块草花混播样地中有18块样地评价达到Ⅰ级、Ⅱ级标准,占总数的81.82％,说明草花混播组合应用效果较好,适合沈阳地区大面积推广应用；有4块样地评价在Ⅲ级、Ⅳ级,占总数的18.18％,主要因为该样块土壤条件较差、组合内品种配比不合理及播种密度较大等原因导致出现单一种强势现象. 相似文献
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将花卉与禾草混播不仅能够丰富群落的景观结构和质感,还能有效地抑制杂草入侵。为研究禾草-花卉混播群落中适用的花卉种类和适合的混播比例,选择22种花卉与2种禾草为试材,按种子质量比设置5个不同梯度的禾草-花卉混播组合,比较不同组合建植群落中花卉的生长特性。结果表明:禾草-花卉混播群落中禾草不影响花卉植物的种类数量,但会抑制花卉植物的萌发率、成活率、植株密度、株高和冠幅的增长,抑制的强度与混播比例呈正相关。花卉与禾草的混播比例应不超过1∶2。为了群落景观的延续性和稳定性,禾草-花卉混播组合中应减少一年生花卉比例,增加多年生花卉比例;一年生花卉应选择萌发早,初期生长速率相对快的种类,多年生花卉应选择幼苗耐阴耐修剪的种类。 相似文献
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片麻岩山地几种草本植物生长特性及水土保持效益分析 总被引：1，自引：0，他引：1
以河北省平山县下峪村新垦地土质坡面为试验地,采用单播、混播2种模式进行播种,研究了几种草本植物在太行山片麻岩山地的生长特性及水土保持效益。结果表明:皇竹草发芽最快,发芽时间为3d,波斯菊次之,发芽最晚的是早熟禾。播种后第15天,皇竹草幼苗最高,高达10.89cm,其次为波斯菊,高度达8.88cm,白三叶草植株最矮,仅为0.67cm。波斯菊植被覆盖度最高,达到了56.9%,皇竹草、波斯菊+紫花苜蓿+皇竹草混播、波斯菊+紫花苜蓿+白三叶草混播坡面的植被覆盖度分别为45.7%、36.1%、34.4%。人工模拟降雨时,播种皇竹草的坡面土壤侵蚀模数、径流系数分别为6.60t·km~(-2)、14.85%,土壤侵蚀程度较轻,水土保持效益最好;水土保持效益较好的有波斯菊+紫花苜蓿+白三叶草混播、波斯菊,土壤侵蚀模数分别为11.13、12.70t·km~(-2),径流系数分别为19.69%、21.34%。因此,将波斯菊、皇竹草、紫花苜蓿、白三叶草进行混合播种,具有良好的水土保持效益。 相似文献
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以宜昌市区和三峡坝区的边坡为调查对象,采用典型取样法,共调查边坡51处,样方192个,统计了边坡的基本情况,对边坡绿化效果进行了评价,对边坡绿化植物的物种数量特征、结构组成和配置模式进行了分析。结果表明:被调查区域边坡绿化整体效果较好,评价等级达到好和较好的占到了总数的60.7%;该地区的常见边坡植物有40种,包括草本23种,藤本7种,灌木10种;草本植物中外来种占到了50%;草本层和灌木层的多样性水平明显高于藤本层;该地区的边坡绿化植物配置模式主要有3种:草坪(草花)型、藤-灌型、灌-草型,其中灌-草型应用得最多。最后,探讨了目前边坡生态防护存在的问题并提出解决对策。 相似文献
10.
对10个混播组合草坪草在成都地区的综合表现进行了研究,分别对建植速度、密度、叶片质地、绿度、抗病性、盖度、均一性、综合评定共8项质量进行综合评价.结果表明:10种不同混播草坪质量均有所差异,抗病性最强的为处理5,成坪最快、叶片质地最好的为处理9、处理10,而处理1、处理4组合的质量综合评价最好,处理6这一组合的质量综合评价最差. 相似文献
11.
卫河四标段植物应用调查与评析 总被引：1，自引：0，他引：1
在景观营造中,科学地选择园林植物并对其进行合理的配置是直接影响工程质量和景观效果的主要因素。为了解河南新乡卫河绿化后的景观效果,对卫河四标段进行了实地调查和分析。结果表明:四标段现有乔灌木及地被种类26科39属51种,其中常绿种类21种,占41.18%;落叶种类为30种,占58.82%。树种结构因子中乔灌比为0.74,常绿比为0.42,树木密度为10.97m2/株;乔木密度25.81m2/株、灌木密度19.07m2/株。群落结构以乔灌草为主,其次是乔草和灌草。 相似文献
12.
海岛矿山生态修复边坡植物多样性分析 总被引：2，自引：0，他引：2
通过对舟山市16个修复边坡进行植被恢复状况的调查,分析了其边坡植物的多样性。结果表明:恢复时间较长、矿区的土壤基质良好,水分条件充足,矿区周围原生植被较好的地点植被恢复后的植物种类丰富度较高。舟山市边坡复绿植物种类较多,其中种数最多的是禾本科,其次是豆科、菊科、木犀科、蔷薇科、山茶科、樟科、苦木科。从群落组成结构看,主要形成了以马棘、紫穗槐等灌木为优势种的乔灌草植物群落结构。草本、木本植物的均匀度都较高,木本植物的多样性和丰富度较草本的高。结合植被调查和植物多样性分析的结果,针对海岛特殊的气候环境提出了海岛边坡修复植物选择原则,同时,类比与海岛边坡类似条件下生长良好的植物,建立了几种植物配置模式,为同类型的边坡绿化植物的选择提供参考。 相似文献
13.
Single-family residential neighborhoods make up large areas within cities and are undergoing change as residences are renovated and redeveloped. We investigated the effects of such residential redevelopment on land cover (trees/shrubs, grass, building, and hardscape) in the 20 largest cities in the Los Angeles Basin from 2000 to 2009. We identified spatially stratified samples of single-family home lots for which additional square footage was recorded and for which additional construction was not recorded by the tax assessor. We then digitized land cover on high-resolution color imagery for two points in time to measure land cover change. Redevelopment of single-family homes in Los Angeles County resulted in a significant decrease in tree/shrub and grass cover and a significant increase in building and hardscape area. Over 10 years, urban green cover (trees/shrubs and grass) declined 14–55% of green cover in 2000 on lots with additional recorded development and 2–22% of green cover in 2000 for single-family lots for which new permits were not recorded. Extrapolating the results to all single-family home lots in these cities indicate a 1.2 percentage point annual decrease in tree/shrub cover (5.6% of existing tree/shrub cover) and a 0.1 percentage point annual decrease in grass cover (2.3% of existing grass cover). The results suggest that protection of existing green cover in neighborhoods is necessary to meet urban forest goals, a factor that is overlooked in existing programs that focus solely on tree planting. Also, changing social views on the preferred size of single-family homes is driving loss of tree cover and increasing impervious surfaces, with potentially significant ramifications for the functioning of urban ecosystems. 相似文献
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对福建省华安县公路建设项目植被现状进行调查,结果表明：现状植被生态类型除农田耕地、茶园、竹林、果林和杉木林、巨尾桉林外,余为次生杂生性灌草植被,植物区系成分和群落类型均属广布性的种类与群落类型。根据调查,果林、竹林、杉木、巨尾桉植物群落结构简单,林下植物较少,一般灌木层较为稀疏。物种多样性指数表明,评价范围内乔木层和灌木层的多样性指数较低。 相似文献
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A common form of land degradation in desert grasslands is associated with the relatively rapid encroachment of woody plants,
a process that has important implications on ecosystem structure and function, as well as on the soil hydrological and biogeochemical
properties. Until recently this grassland to shrubland transition was thought to be highly irreversible. However recent studies
have shown that at the early stages of shrub encroachment in desert grasslands, there exists a very dynamic shrub–grass transition
state with enough grass connectivity between the shrub islands to allow for fire spread. In this state fire could play a major
role in determining the dominance of grasses and their recovery from the effects of overgrazing. Using a spatially explicit
cellular automata model, we show how the patch-scale feedbacks between fires and soil erosion affects resource redistribution
and vegetation dynamics in a mixed grass–shrub plant community at landscape to regional scales. The results of this study
indicate that at its early stages, the grassland-to-shrubland transition can be reversible and that the feedbacks between
fire and soil erosion processes may play a major role in determining the reversibility of the system. 相似文献
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Effects of spatial habitat heterogeneity on habitat selection and annual fecundity for a migratory forest songbird 总被引：1，自引：1，他引：0
Understanding how spatial habitat patterns influence abundance and dynamics of animal populations is a primary goal in landscape
ecology. We used an information-theoretic approach to investigate the association between habitat patterns at multiple spatial
scales and demographic patterns for black-throated blue warblers (Dendroica caerulescens) at 20 study sites in west-central Vermont, USA from 2002 to 2005. Sites were characterized by: (1) territory-scale shrub
density, (2) patch-scale shrub density occurring within 25 ha of territories, and (3) landscape-scale habitat patterns occurring
within 5 km radius extents of territories. We considered multiple population parameters including abundance, age ratios, and
annual fecundity. Territory-scale shrub density was most important for determining abundance and age ratios, but landscape-scale
habitat structure strongly influenced reproductive output. Sites with higher territory-scale shrub density had higher abundance,
and were more likely to be occupied by older, more experienced individuals compared to sites with lower shrub density. However,
annual fecundity was higher on sites located in contiguously forested landscapes where shrub density was lower than the fragmented
sites. Further, effects of habitat pattern at one spatial scale depended on habitat conditions at different scales. For example,
abundance increased with increasing territory-scale shrub density, but this effect was much stronger in fragmented landscapes
than in contiguously forested landscapes. These results suggest that habitat pattern at different spatial scales affect demographic
parameters in different ways, and that effects of habitat patterns at one spatial scale depends on habitat conditions at other
scales. 相似文献
18.
Context
Fire and controlled grazing have been widely adopted as management interventions to counteract woody shrub proliferation in many arid and semiarid grassland systems. The actual intensity of grazing and fire, along with the timing of the interventions, however, are difficult to determine in practice.
ObjectivesThis study aims to establish model simulations to access the long-term landscape changes under different land management scenarios.
MethodsWe developed a cellular automata model to evaluate landscape dynamics in response to scenarios of grazing, fire, time of intervention, and initial coverage of grasses and shrubs.
ResultsWith current grazing intensity and fire suppression, the landscape may shift to a shrub-dominated landscape in 100–150 years. An appropriate combination of grazing and fire management could help maintain over 50% of grass cover and reduce the shrub cover to less than 2%, keeping the landscape highly reversible. Even using 1% grazing intensity and periodic fire once a year, the management tools should be implemented in 60 years, otherwise, they may lose effectiveness and the vegetation transition to grasslands would become impossible.
ConclusionsThis study highlighted that the reintroduction of fire not only directly removes shrubs but also reallocates soil water and resources among different microsites, which may accelerate grass recovery and suppress shrub regrowth, potentially reversing the shrub invasion process. The combined grazing and fire management plans should be carried out before a threshold time depending on the chosen management tools.
相似文献19.
Matrix habitats are known to influence the movement patterns of a variety of species but it is less well known whether these
effects have strong implications for spatial population dynamics, including the spread of biological introductions. Using
a spatially explicit simulation model parameterized with empirical data, we examine how grass and shrub matrix habitats, each
offering different resistance to dispersal, influence the spread and impact of a biocontrol agent, Aphthona lacertosa, on the invasive weed, leafy spurge. Model predictions indicate that differential responses to matrix habitat have little
effect on the agent’s spread over the study landscape and this is supported by statistical models fit to observed A. lacertosa incidence on the same landscape. Subsequent experimentation with the simulation model suggested that A. lacertosa colonization rates were largely unaffected by increases in amount of the more restrictive shrub matrix. However, simulations
of an hypothetical species with greater overall dispersal ability but reduced dispersal rate through shrub matrix showed that
colonization rates were noticeably reduced when the percentage of shrub matrix on the landscape approached 50%. Combined these
results suggest that some tailoring of release strategies may be required to accommodate the unique dispersal capabilities
of different biocontrol agents on particular release landscapes, but for A. lacertosa there appears to be little effect of matrix habitat structure on rates of spread. 相似文献
20.
研究了北京市密云县西沟林场封山育林地区不同封育措施灌木林地土壤物理性状和土壤渗透性能.结果表明:在封造、封禁、封育3种封育措施的灌木林地中,土壤容重为:封造灌木林地>封禁灌木林地>封育灌木林地,土壤总孔隙度、非毛管孔隙度、毛管孔隙度、饱和蓄水量、有效涵蓄量、毛/饱和蓄水量的顺序为:封造灌木林地<封禁灌木林地<封育灌木林地.封育灌木林地土壤初始入渗速率是封禁灌木林地的1.45倍,是封造灌木林地的1.85倍.前30 min累积入渗量顺序为:封育灌木林地>封禁灌木林地>封造灌木林.从土壤物理性状和渗透性能来看,封育措施能更好的改良土壤结构、降低土壤容重和增加土壤总孔隙度,提高灌木林土壤水源涵养和理水调洪功能. 相似文献