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以新丰县岭南红叶之乡建设作为研究对象,分析以往生态景观林带建设中存在的不足,在此基础上进一步明确今后建设的范围、对象、目标、布局及建设内容。同时,根据地类、林种、生态区位、经营目的、景观效果的差异,归纳出包括造林型、改造型、补植型等3大类18种建设模式,并提出相关建议,以期为其他地区开展景观绿化建设提供借鉴。
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上海绿地群落冠层的UVB屏蔽作用 总被引：3，自引：0，他引：3
文章选择上海绿地典型植物群落类型进行UVB屏蔽效率测定,分析绿地类型、植物配置方式对屏蔽效率的影响作用,并对群落优势种高度、枝下高等特征与群落屏蔽效率相关关系进行了初步研究。研究结果表明:(1)所测定植物群落中UVB屏蔽效率较高的为毛竹群落、水杉群落、香樟群落、女贞群落、朴树群落和雪松群落,UVB屏蔽效率最高为98.4%的女贞群落,最低为17.1%的红叶李群落(2)所测定群落UVB平均屏蔽效率为76.9%,即群落内2m高处UVB辐射值仅为全光照旷地20.2%。(3)植物群落内UVB辐射通量与群落郁闭度呈极显著负相关关系,相关系数为0.749,而与群落优势种平均高度和平均冠幅相关性不显著。
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阳泉市位于山西省东部,太行山中段西麓,总面积4570km2,总人口124.26万人,其中建城区面积42km2,人口46.13万人。境内大部分属于土石区,山谷纵横,地形复杂,山地和丘陵占总面积的80%,仅有西烟、盂县、洗马堰等几块盆地。
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鉴真乃唐代高僧,江苏扬州人。八世纪中叶,应日本邀请,五次航海均告失败,虽双目失明,仍矢志不渝,于古稀之年,从张家港古黄泗浦,再次扬帆东渡,终获成功,高僧把我国的佛学、医学、语文、建筑、雕塑、书法和印刷等传播到扶桑。今天向广大读者介绍鉴真高僧成功起航的地方——张家港。
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李树花期受晚春低温阴雨冻害是限制李子商品化生产发展的主要问题。我所从美国奥本大学引进了27个优良李品种（系）,经过近10a的试验观察,结果表明：圣罗莎、欧扎克总理、奥本罗莎、奥本82－1,蜜斯李、紫李、奥本樱桃李等综合经济性状优良,适宜在湖北各地推广。 相似文献
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Nursery stock of peach (Prunus persica L. Batsch, cv. O'Henry), nectarine (P. persica L. Batsch, cv. Fantasia), plum (P. salicina Lindel., cv. Casselman), apricot (P. armeniaca L., cv. Tilton), almond (P. dulcis Mill., cv. Nonpareil), prune (P. domestica L., cv. Improved French), cherry (P. avium L., cv. Bing), oriental pear (Pyrus pyrifolia Rehd., cv. 20th Century), and apple (Malus pumula Mill., cv. Granny Smith) were planted in open-top chambers on April 1, 1988 at the University of California's Kearney Agricultural Center located in the San Joaquin Valley (30 degrees 40' N 119 degrees 40' W). Trees were exposed to three atmospheric ozone partial pressures (charcoal-filtered air (C), ambient air (A), or ambient air + ozone (T)) from August 1 to November 17, 1988. The mean 12-h (0800 to 2000 h) ozone partial pressures measured in open-top chambers during the experimental period were 0.030, 0.051, and 0.117 microPa Pa(-1) in the C, A and T treatments, respectively. Leaf net CO(2) assimilation rate decreased linearly with increasing 12-h mean ozone partial pressure for the almond, plum, apricot, prune, pear, and apple cultivars. Stomatal conductances of apricot, apple, almond, and plum decreased linearly with increasing ozone partial pressure. Cross-sectional area relative growth rates of almond, plum, apricot, and pear decreased linearly with increasing ozone partial pressure. Net CO(2) assimilation rate, stomatal conductance, and trunk growth of cherry, peach and nectarine were unaffected by the ozone treatments. Reduced leaf gas exchange probably contributed to ozone-induced growth reduction of the susceptible species and cultivars. Several of the commercial fruit tree species and cultivars studied were relatively tolerant to the ozone treatments. 相似文献
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A leaf disc bioassay was employed to investigate the influence of host species of deciduous fruit trees, like apple, peach,
plum, cherry and apricot, on the development and reproduction of the hawthorn spider mite Tetranychus viennensis Zacher in the laboratory under conditions of 25±1°C, 60±10% RH and a photoperiod of 16 h: 8 h light: dark. This was done
by determining the duration of each life stage of the mites, the intrinsic rate of population increase (r
m
), mean generation time (T) and net reproductive rate (R
0) of the spider mites on each of the host plant species. Differences in life table parameters of the spider mite among host
plants were analyzed with the jack-knife method. The results indicated that plum might be the best suitable plant for the
spider mite among the plants tested due to shorter developmental period and higher intrinsic rate of increase, whereas cherry
and apricot were least suitable due to their long developmental duration and low intrinsic rates of increase. When the spider
mites were transferred from apple to other fruit trees, negative effects on developmental duration, fecundity and life table
parameters were found in the first generation, but the effects faded out in succeeding generations. When transferred onto
plum and peach, the spider mite adapted to the new hosts in the second generation; however, on cherry and apricot, it adapted
in the third generation.
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Translated from Acta Ecologica Sinica, 2005, 27(7) [译自: 生态学报, 2005, 27(7)] 相似文献
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在对杜尔伯特蒙古族自治县靠山种畜场建立的3种草牧场立体开发模式进行调查和统计分析的基础上,确定了樟子松是杜尔伯特蒙古族自治县草原防护林的主栽树种,沙棘是固沙林、灌木饲料林的主要树种,绥李、黄太平、樱桃是草牧场区的主要经济树种;确定了樟子松移植大苗造林的最佳时间、移植桶规格和苗木规格。草牧场樟子松疏林立体开发模式,生态、经济效益显著;草场防护林体系网带疏块、乔灌草药复合模式,形成了生态和经济上比较稳定高效的综合体系;经济林开发利用模式产值是农田的8倍。比普通经济纯林提高34．8％。 相似文献
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Root and shoot characteristics related to drought resistance were compared among cultivated peach (Prunus persica (L.) Batsch.), P. andersonii (Nevada Desert almond), P. besseyi (western sand cherry), P. maritima (beach plum), P. subcordata (Sierra or Pacific plum), and P. tomentosa (Nanking cherry). In all species, shoot characteristics were more closely associated with drought adaptation than root characteristics. The most xeric species, P. andersonii, had the lowest specific leaf area, smallest leaves, highest stomatal conductance (before stress), highest rate of carbon assimilation (A), high root length/leaf area and root weight/leaf area ratios, and the highest leaf nitrogen content on an area basis. Root hydraulic conductivity was similar for all species, indicating a lack of importance of this parameter for drought resistance. During a 5-7 day drought, water use efficiency (WUE) increased as shoot water potentials (Psi) declined to -3.0 to -4.0 MPa for the xeric P. andersonii and P. subcordata, whereas after an initial increase, WUE decreased with declining Psi in the -1.5 to -3.0 MPa range for the more mesic P. maritima, P. persica and P. tomentosa as a result of non-stomatal limitations to A. Carbon assimilation rate decreased linearly with Psi during drought in all species, but the Psi at which A reached zero was not associated with drought adaptation. We conclude that the variation in leaf characteristics among Prunus species could be exploited to improve the drought resistance of commercial cultivars. 相似文献
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配置一定比例授粉树种，是提高授粉效果获得丰产的基础。授粉树比例幼龄期高于成龄期，授粉树花期应与天目蜜李基本一致、果形近似、品质好、抗性强的优良品种，这样才能确保果品的质量与产量。 相似文献
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通过在乔木树种上嫁接繁殖，可使榆叶梅形成良好干形，在园林绿化工程中有更好的应用价值。试验证明，李树与榆叶梅嫁接亲合力好，可以作为乔化榆叶梅的嫁接砧木，嫁接后可以形成较好的干形，达到乔化榆叶梅的目的。 相似文献
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Esat Gümüşkaya Emrah Peşman Hüseyin Kirci Mualla Balaban Uçar 《Wood Science and Technology》2011,45(3):573-582
The aim of this study was to investigate the effects of plum gum liquor and sodium perborate addition to oxygen delignification
process on spruce kraft pulp properties. Yields and viscosity of pulp were protected against oxidative attack, when kappa
number of pulp was not changed by adding plum gum to oxygen delignification process. Delignification ratio improved by 7.4%
without any viscosity loss by adding only 0.25% sodium perborate as active oxygen with plum gum liquor to the oxygen delignification
process. It was found that crystallinity of pulp was improved by adding plum gum and sodium perborate to oxygen delignification.
It was also determined that sodium perborate had an affirmative effect on delignification ratio, when plum gum affected pulp
viscosity positively. 相似文献