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通过对松墨天牛在雪松上的危害调查和防治试验,结果表明:松墨天牛易危害新栽雪松和生长弱势的雪松;速扑杀、氧乐果、敌敌畏等杀虫剂进行注射防治松墨天牛幼虫效果显著。 相似文献
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对上海电气集团培训基地雪松[Cedrus deodara(Roxb.)G.Don.]、黑松(Pinus thunbergii Parl.)林地的土壤进行了研究分析。结果表明:雪松、黑松林地的土壤p H值较高,分别达到7.99和8.70;土壤的EC值为0.85ms/cm和0.76ms/cm,土壤有机质含量分别为1.72%和1.45%,碱解性N的含量分别为62.7mg/kg和56.5mg/kg,即土壤中的EC值、有机质含量和碱解性N含量均低于正常生长所需,对雪松、黑松的生长造成了不利的影响;雪松、黑松林的土壤中有效磷的含量丰富;黑松林地中土壤的微生物数量较低,影响了雪松和黑松的生长。为此,提出采取建设围栏、增施有机肥等措施来改善土壤的理化性质。 相似文献
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雪松[Cedrusdeodara(Roxb.)G .Don]原产印度、阿富汗、喜马拉雅山西部,适应范围较广,从亚热带到寒带南部都能生长。雪松寿命较长,耐寒能力较强,干形通直,材质坚致,少翅裂,有芳香,能耐久,树姿雄伟苍翠,树冠塔形,枝条平展,树形优美,叶丛匀称,球果华丽,具有很高的观赏价值,与南洋杉、日本金松同为世界著名三大珍贵观赏树种,也是珍贵的用材树种。雪松育苗所采用的繁殖方法主要有播种法、扦插法和嫁接法等。嫁接法常用黑松做砧木,春季用埋土劈接法嫁接,此法繁殖率较低,并易出现接口不亲合现象。因此,雪松繁殖育苗一般采用播种法和扦插法。雪松… 相似文献
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雪松(Cedrus deodara),是常见的园林绿化优良树种。近年来,随着绿化水平的提高,3米以上大规格的雪松需求量增加,而小苗滞销。为促进雪松苗期生长,缩短培育大苗时间;我们于1986年使用具较高生理活性的植物激素——赤霉素,对雪松进行叶面喷施试验,并对处理的浓度、时间、次数和雪松苗期生长效应进行了探讨。现将初步结果报道如下: 材料与方法 (一)试验材料 1.立地条件:本试验设在武进县雪堰乡共建林果场,圃地土壤为轻壤到中壤,前茬为苹果树林场,肥力中等。 2.供试雪松为当年生实生苗。播种方式:大田播种,点播。行距为12厘米,每行雪松双列,出苗率为50—75％。株行距为6×6厘米。 相似文献
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铅笔柏(Sabina virginiana A.)树型优美,材质优良,根系发达,枝叶繁茂,适应性广,抗逆性强。原产北美,本世纪初引入我国。北起辽南、北京,南到浙江舟山、江西庐山均有栽培(江苏、山东、安徽已造林),生长良好。为了进一步选拔作为用材林、防护林的优良母树.于1987年开始进行了铅笔柏的选优工作。 相似文献
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合肥城市森林减少大气污染的效果 总被引：19，自引：6，他引：13
树木主要通过气孔吸收气态污染物,同时通过滞留空气中的微粒而减轻污染,树木较高的覆盖率可能会减少挥发性有机物的释放量,定量研究表明,合肥市1998年吸收空气污染物约为151.5t,树木7月份(着叶季节)吸收污染量高达20t,具有相对较低臭氧生成潜力的植物有香樟属、女贞属、紫薇属、罗汉松属和李属。合肥城市森林总体的臭氧指标得分值为92.4。
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Compatible stem volume and taper equations for Brutian pine, Cedar of Lebanon, and Cilicica fir in Turkey 总被引：2，自引：0，他引：2
Compatible segmented taper and volume functions were developed for Brutian pine, Cedar of Lebanon, and Cilicica fir in Turkey. The proposed models generally performed better for the whole tree, especially for Cilicica fir. Average diameter prediction error was less than 2.2 cm and average volume error was less than 0.009 m3. The proposed models provide needed merchantable stem volume and diameter estimates to any point in the bole based on the 10 relative height classes examined for the three species. Model estimates compared well to existing volume tables currently employed for these three important commercial species. 相似文献
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In vitro regeneration of complete plants from nodal single-bud segments of 2-year-old Australian Cedar (Toona ciliata) trees were obtained under defined nutritional and environmental conditions. Explants were dissected from plants obtained by germination of seeds and growth in pots in a greenhouse. The best medium for shoot regeneration was that of Murashige and Skoog at 1/4 strength with 3% sucrose (1/4 MS), supplemented with 0.1 mg/l IBA and 0.5 mg/l BAP. Rooting of regenerated shoots was observed in MS medium with 0.1 mg/l IBA. Using mature tree material was more difficult. Forced flushing was used to induce shoot development on branches of a 10-year-old tree. Nodal segments of these epicormic shoots formed shoots in vitro on 1/4 MS + 0.01 mg/l IBA + 5 mg/l BAP, but rooting was never observed. 相似文献
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研究以广东省郁南林场大东坑工区内 51 年生灰木莲 Manglietia conifera 为研究对象，对灰木莲树高、胸径、材积、树干通直度、侧枝生长习性等指标进行调查和分析。结果表明：51 年生灰木莲生长良好，胸径平均为 44.28 cm，最大为 79.60 cm，树高平均为 20.79 m，最高为 27.00 m，单株材积平均为 1.48 m3，最高为 3.65 m3。可见，灰木莲引种在广东郁南适应性强，能够生长良好，具有生长速度快，树干通直，自然整枝好等特点，是该地区可以推广种植和培育大径材的优良树种。 相似文献
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为筛选适合广西桂南地区发展的阔叶树种,对桂南地区 9 年生 18 种阔叶树种的树高、胸
径、冠幅、保存率等指标进行调查。结果表明：各树种保存率存在极显著差异,香樟（Cinnamomum
camphora）、土沉香（Aquilaria sinensis）、马蹄荷（Exbucklandia populnea）保存率较差,其他树种保存
率较高 , 表明大部分树种对桂南地区环境适应能力较强。不同树种之间的树高、胸径和冠幅生长存在极
显著差异,通过聚类分析,可将 18 个树种分为 3 个类群,A 类群具有较大的胸径和树高,较快的生长
速度,主要以木兰科植物为主;B 类群生长速度中等,主要以豆科、壳斗科和樟科植物为主;C 类群
生长速度较慢,多为豆科植物。香梓楠 (Michelia hedyosperma)、厚荚相思 (Acacia crassicarpa)、山白兰
(M. alba)、米老排 (Mytilaria laosensis)、灰木莲 (M. glanca)、火力楠 (M. macclurei)、蓝花楹 (Jacaranda
mimosifolia) 具有速生且适应性强的特性,降香黄檀（Dalbergia odorifera）、柚木（Tectona grandis）、格木
(Erythrophleum fordii)、土沉香 (A. sinensis) 生长比较缓慢。 相似文献
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Interior Douglas-fir trees in plantations were assessed for size differences related to the level of diseased neighbours infected with Armillaria ostoyae. The four Douglas-fir stands studied ranged from 25- to 34-year-old, and represented the oldest accessible planted stands in the Interior Cedar Hemlock (ICH) ecosystem in British Columbia. Twenty-three to 25, 10-m radius plots were established in each stand. The spatial coordinates, total height, and diameter at breast height of all live and dead trees in the plots were recorded. Subject trees whose competitors were contained in the 10-m radius plots were also identified. Trees were pulled out of the soil using a mechanical excavator and the root systems were surveyed for evidence of infection by A. ostoyae. Stem disks were taken from each tree at 1.3 m above the ground for a determination of basal area. Increasing proportion of diseased trees in the plots resulted in less total plot basal area, but did not affect the mean basal area or height. Individual subject tree basal area was negatively related to the level of disease in surrounding competitors, opposite to expectations; however, diseased subject trees had reduced height and basal area compared to disease-free subject trees. Increasing competition reduced both the height and basal area of the trees, while regular distribution of all trees increased both total and mean plot basal area but not height. Disease incidence at the plot level and in individual subject trees was mainly affected by the neighbourhood conditions in which it grew, and was also related to disease intensity in the tree root systems. Although disease may alter resource partitioning among trees, the utilization of these resources is mostly limited by the increasing disease incidence as the stands age, the higher probability of larger trees being diseased with time, the occurrence of dead trees in clumps, and the high probability that dead trees will eventually infect live neighbours. The widespread belowground incidence of A. ostoyae in the ICH, its rapid colonization of stumps, and its wide host range can reduce site potential in managed stands. 相似文献