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常州市市区行道树树种的选择 总被引：5，自引：0，他引：5
调查分析了常州市市区行道树绿化存在树种单一、配置形式单调、常绿品种偏多、树种选择不科学等问题 ,提出了市区行道树绿化树种选择的原则、配置方法及适宜用作行道树的一些优良树种的建议。 相似文献
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禄劝县城树种规划研究 总被引：1，自引：1，他引：0
对禄劝县城园林绿化中的树种应用现状进行了实地调查,记录了现有树种123种,分属52科94属,其中裸子植物14种,被子植物109种,常绿树种92种,落叶树种31种.对乡土树种应用不足、绿化树种色彩单一等绿化中存在的问题进行分析,确定了树种规划原则及指标体系.藉此提出了6种园林绿化基调树种,16种骨干树种,302种一般树种和84种潜在价值树种. 相似文献
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论述了辽西干旱地区绿化树种选择的重要性,提出绿化树种选择原则,针对不同地域、立地条件有针对性地提出绿化树种及绿化方法. 相似文献
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通过对福建省乡土野生绿化树种调查,筛选出园林观赏价值高、经济效益好的福建山樱花、香港四照花等10种乡土野生绿化树种进行驯化栽培试验,总结出栽培配套技术和3年生各树种生长情况,投入产出比达1∶3~1∶13,获得显著社会、生态和经济效益,为园林规划和林业生产提供科学依据。 相似文献
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概述了我国东北地区绿化树种的引种以及城市中绿化树种的应用状况,并对东北地区绿化树种引种与应用存在的问题与对策进行了探讨,以期为深入研究和开发适宜东北地区的绿化树种资源提供参考。 相似文献
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通过对县域绿化树种现状的分析,从树种的管理、树种的类型、搭配原则等方面,探讨了绿化树种选择方法及原则,以期对今后景观特色绿化实践工作起到借鉴作用. 相似文献
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通过分析初冬园林树木枝条内养分含量变化和落叶内营养元素含量差异,为指导园林树木越冬养护实践和景观设计中科学选择树木种类提供理论依据。选择大庆市小游园5种园林树种,测定枝条养分和落叶养分含量。结果表明:10月26日至11月16日间,丁香枝条氮、磷含量分别降低了68.28%、35.61%;偃伏莱木枝条氮、钾含量分别降低了25.93%、37.40%;垂枝榆枝条氮、磷、钾含量变化表现为先升高后降低,11月较10月降低了24.08%、19.78%、9.32%;榆树枝条磷、钾含量表现为一直升高的变化,升高幅度分别为21.78%、123.86%;落叶中垂枝榆氮含量为1.88%,榆树磷含量为1.60%,榆叶梅钾含量为1.88%。初冬园林树木枝条内养分含量逐渐降低,落叶平衡补充了土壤营养元素。 相似文献
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观果树种配植与城市鸟类生物多样性保护 总被引：13，自引：0，他引：13
通过对观果树木,尤其是冬季挂果的观果树木的果期物候调查,以及在冬季留鸟对挂果树木的访问情况记录,讨论了观果树木在城市园林中配植与城市鸟类多样性保护的关系。合理配植冬季挂果树种,对吸引更多的鸟类、维持城市生物多样性有重要意义。 相似文献
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P. Felker C.T. Sorensson D. Ueckert P. Jacoby E. Singer R. Ohm 《Agroforestry Systems》1998,42(2):159-179
Seventy seedlots of Leucaena leucocephala, L. pallida, L. diversifolia, L. retusa, L. esculenta, L. confertifolia, L. greggii
and L. pulverulenta and various hybrid combinations were examined for survival to freezing weather, biomass production, leaf
protein content and in vitro dry matter digestibility in Texas. Three sites along a 600 km north-south transect were chosen
to provide a wide range in exposure to freezing weather. The minimum temperature on the warmer Three Rivers site was −7 °C
while the minimum temperatures on the colder Vernon site was −14 °C. At the Three Rivers site where −7 °C temperatures occurred
and where forage production was a priority and some winter frost damage was not a problem, L. leucocephala K636 and hybrids
containing L. diversifolia and L. pallida have the most promise. If total lack of damage to −7 °C is essential, species such
as L. retusa, L. pulverulenta (seedlot 61, 62) and hybrids such as L. retusa × L. greggii (53) and L. retusa × L. pulverulenta
(55) have the greatest potential. This study examined only one family from each of the cold-hardy species as a parent in the
promising hybrids. As extensive intraspecific genetic variation is present within these leucaena species there is great potential
to find hybrids with much better combinations of cold hardiness, forage production, leaf protein and dry matter digestibility.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献
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大叶冬青、乐东拟单性木兰，洒金桃叶珊瑚３种常绿阔叶树，在南京，盱胎，新浦纬度各相差约１°的地方试栽后，前两地可安全越冬，新浦栽种大叶冬青和洒金桃叶珊瑚可以成功，栽乐东拟单性木兰则要注意小环境的选择。 相似文献
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Effects of shade on arbuscular mycorrhizal colonization and growth of crops and tree seedlings in Central India 总被引：1，自引：0，他引：1
Ashok Shukla Anil Kumar Anuradha Jha Om Prakash Chaturvedi Rajendra Prasad Ajit Gupta 《Agroforestry Systems》2009,76(1):95-109
The study was conducted to investigate the effects of different light intensities (25, 50, 67, and 100% of full sun [open])
on arbuscular mycorrhizal (AM) colonization and growth of two intercrops (a rainy season crop, Phaseolus mungo Roxb. var. PU-35 and a winter crop, Triticum aestivum L. var. WH-147) and seedlings of two multipurpose tree species (Eucalyptus tereticornis Sm. [Clone C-7, ITC, Bhadrachalam] and Albizia procera Benth.) of Central India. The results showed that various plant growth parameters viz., shoot length, dry weight and phosphorus
(P) uptake were adversely affected by low light intensity. Inoculations with AM fungi (Acaulospora scrobiculata Trappe, Glomus intraradix Schenck & Smith and an unidentified Glomus species) increased the plant growth on account of all measured parameters under tested light conditions. Mycorrhizal efficiency
of different AM fungi varied in narrow range. AM inoculants were more efficient at higher light intensity in above mentioned
plant species, except wheat. Data on colonization of P. mungo, T. aestivum, E. tereticornis and A. procera showed that formation of arbuscules, vesicles and sporocarp was delayed by lower light intensity. Colonization index of host
roots and spore counts increased with increase in light intensity during successive months after inoculation. Data on effect
of light regimes on microclimate of net house showed that lux meter reading decreased as per grades of shading nets used during
both rainy and winter seasons. With increase in light intensity, ambient temperature, soil surface temperature and sub surface
temperature at 15 cm depth increased, except that the ambient and soil surface temperature in control (open) were slightly
lower than net house observations during January and February. Value of ambient temperature varied in narrow range, with in
treatments as compared to soil surface and sub soil surface temperature at 15 cm depth. Soil surface temperature at 25% of
full sunlight was less than respective control values by 2–11°C and sub soil temperature at 15 cm depth was less by 4–12°C.
The values of different microclimate parameters varied in narrower range during winter season as compared to rainy season.
While ranking the importance of two factors studied—light and AM fungi—for their effect on the growth and P uptake by different
plant species, inoculations with AM fungi came in the first place (explained 50–82% variation) and light substantially increased
the values of R
2 in stepwise regression analysis (forward selection). The results suggest that AM inoculation may enhance the growth and P
uptake of intercrops under tree shade and the tree canopy management is likely to increase the efficiency of AM inoculants
in agroforestry systems. Use of excessive shading (25% of full sun or more) in nurseries may be avoided and PAR (photosynthetically
active radiation) lamps may be used to increase growth and colonization index of tree seedlings. 相似文献
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Cristina Martínez-Garza Marcela Osorio-BeristainDavid Valenzuela-Galván Alondra Nicolás-Medina 《Forest Ecology and Management》2011,262(12):2207-2218
Domestic livestock grazing and firewood extraction are chronic and pervasive disturbances in dry secondary forest that reduce diversity and modify composition. Exclosure of such disturbances may allow the reestablishment of original diversity. To investigate potential vegetation recovery following 30 years of perturbation, seed rain was evaluated monthly during 3 years in 96 0.78 m2 seed traps located in eight exclosures established in 2006 in a species-poor secondary dry forest in central Mexico. Twelve additional seed traps were located outside the exclosures in 2010 for comparison purposes. Baseline diversity of seed sources (trees, ?5 cm DBH) was recorded to compare standing tree composition with seed rain. Also, baseline diversity of potential primary (birds) and secondary (ants) dispersal vectors were registered to infer current plant-animal interactions. Total seed rain over 3 years within the exclosures comprised 180,375 seeds from 61 woody species, an average of 1.12 seeds/m2/month. Half of these species (31) and 95% of the seeds falling within the exclosures belonged to trees typical of perturbed sites. Sixty percent of all recorded seeds belonged to an early-successional, bird-dispersed shrub (Hamelia patens Jacq., Rubiaceae). Seed rain at one non-excluded plot was dominated by the wind-dispersed early-successional tree Heliocarpus sp. (Tiliaceae). Richness and seed density increased significantly in the second year of exclusion; however, by the third year, richness remained constant while seed density decreased. Seed rain was richer and more abundant during the dry season and was dominated by wind-dispersed species. Phenology, successional status and the dispersal modes of woody species explained most variance in richness and seed density of seed rain in early-successional dry forest. Seeds of early-successional species were dispersed in equal measure by abiotic and biotic vectors, whereas biotic vectors dispersed a higher density of late-successional seeds. The amount and timing of fall of abiotically dispersed seeds of the three most abundant species in the standing tree community may prolong their current domination of the landscape. However, even when richness in the seed rain within exclosures remained constant through time, composition was gradually shifting towards animal-dispersed species which may start a positive feedback producing an increase in animal visitation and a further increase of richness. 相似文献
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邓恩桉优树的选择标准 总被引：3，自引：0，他引：3
以1988、1991年种植在广西柳州、桂林两地的邓恩桉为选优林分对象,用5株优势木对比法进行选优,同时研究了优树的入选标准.通过对50株候选优树和250株5株优势木生长量数据、分枝与干形得分值的分析,确定了本次选优的标准为:胸径≥优势木平均胸径1.2倍(或树高≥优势木平均树高1.06倍)、单株材积≥优势木平均单株材积1.44倍、分枝与干形二者综合得分5分以上(含),符合该选优标准的候选优树有26株,入选率为52%.该选优标准适合所研究的林分及与研究林分情况相近的邓恩桉林分的选优. 相似文献
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【目的】城市鸟类及蜂蝶类群落结构多样性是城市生物多样性的重要组成部分和生态环境质量的重要评价标准之一。了解城市园林绿地食源树种的应用,探讨食源树种的生态特性及其景观特征。【方法】调查了广州市12处城市绿地食源树种的应用,观察鸟类及蜂蝶类的取食情况,记录绿地中食源树种的种类、应用频次、配置方式及生长状况,归纳分析食源树种群落构成、观赏特性、生态性等。【结果】广州园林绿地常见食源树种有23科33属45种,其中鸟类食源树种25种,蜂蝶类食源树种20种,以桃金娘科、桑科、大戟科为主,并以乡土种为主、外来驯化种为辅;食源树种的观赏与被取食时间主要集中于春夏季(31种),秋冬季的相对较少(16种)。【结论】广州市绿地的食源树种资源丰富,约300种,但常见鸟类及蜂蝶类食源树种仅占18%,结合良好适应性、抗逆性、取食性、观赏性,归纳出20种优势乡土食源树种;同时对食源树种群落组成结构进行分析,在兼顾食源树种的观赏性与生态性的基础上,设计出6组可在广州城市园林绿地推广应用的生态配置群落,采用树种混交与立体复合栽植的形式,乔、灌、草结合,形成丰富的水平与垂直植物群落结构,提高绿地生境异质性,增加食源树种的数量及丰富度,提供丰富稳定的食物来源,为鸟类及蜂蝶类提供多样的稳定栖息地。研究结果将对城市园林绿地食源树种的合理选择与科学配置应用,以及营造鸟类及蜂蝶类昆虫生态景观具有现实指导意义。 相似文献