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“五一”节日期间,应朋友之邀,到八卦山一游。怡人仙道八卦山。“八卦山”因其地形地貌形似“八卦图”而得其名。置身“八卦山”。一股浓烈的绿的芬芳扑面、迎怀。绿意葱茏。气息清新。给你强烈的感觉就是一个字——绿。她绿得彻底,绿得妖娆,绿得芬芳,绿得灿然,绿得自在,绿得饱满。绿得甘冽。看。那绿色的树林,让人充满想像,那象征着生命的绿色。绝对是最舒服的颜色。那芙丽的树林不是用来漫步游荡的,而是用来让人抬头现望、欣赏的,欣赏树叶与阳光的完芙结合。阳光在叶的缝隙里轻轻地射进来,像一位绅士,永远都是那么礼貌和有风度。阳光照得叶子闪闪发光。就像没有瑕疵的玉石。晶莹、玲珑。它们拥有淡淡的百合花的味道,清新脱俗.用自己的肢体去实现生命的价值。 相似文献
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百年期盼。百年梦圆。2008年8月8日。伴随中华民族伟大复兴的脚步。中国人的奥运梦想终于实现了。北京这座六朝古都。800多年皇城的中轴线上,故宫展现着沧桑的姿态。“鸟巢”呈现着现代的容颜。前者是历史老人的大度与超然,后者如时代天骄的自信与稳健。此刻一同站在了2008年北京奥运的历史时刻前。迎接着五洲之风四海之澜。今天,本刊记者兵分两路。分别在故宫、天安门附近、“鸟巢”附近纪录行人那些真真切切的感受。实实在在的故事。那些充满生活气息的期待与渴盼。骄傲与荣耀。带给我们的是不寻常的感动和美好。 相似文献
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小院的东北角,堆放了大量的建筑垃圾,形同小丘。天长日久,便生出许多植物来。以草本为多,间夹低矮的木本。几棵南瓜和香瓜,于石头缝里绽放生机,在荒芜中展示生命的精彩。这些植物怎么来到了此处?问这样的问题,对于出身农村的我来讲,是很愚蠢的。飞籽成林。这种子当然是飞来的。一是随风飘落,二是飞鸟撒下了粪便,其中便有没消化的植物种子。仲秋时节,天气凉爽,我喜欢到与之毗邻的栅栏边锻炼身体。秋虫唧唧,阳光生彩,一个蓬蓬勃勃的野生世界,充满了无限的生机。每每看到有如工棚里建筑工人一样随遇而安的南瓜花和香瓜花,我的心里就特别安宁。为什么呢?我不甚清楚,但我天天来,天天锻炼,天天看它们,内心里越发恬静。那些大大小小的花朵,每天都在发生微妙的变化。从绽放到盛开,那是花朵一生一世的辉煌。 相似文献
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在关乎共同利益及未来面前,人类似乎正在摈弃政治、宗教、信仰等偏见,渐渐在趋向大同。本刊在去年9月号上。对美国前副总统戈尔写的《无法忽视的真相》进行了解读。那本书以无可辩驳的事实,客观地展示了全球性的生态危机,指出:人类自救只有十年期。超过了这个期限、许多危机便无法逆转。无独有偶。在去年9月。新华出版社出版了姜春云主编的专著《偿还生态欠债——人与自然和谐探索》。此书展示的是中国的生态危机。与戈尔不同的是。此书不只列举了现象和危害,更重要的是对生态危机的深层原因进行了尖锐剖析。并借鉴国内外众多专家学者最新研究的成果,对解决生态危机提出了应对之策。该书内容翔实丰富。数据准确权威,方法科学实用。结论严谨缜密。这是一束穿越历史的理性之光,让几十年来沉迷在巨大发展的我们,看到了自身的疏忽以及由此欠下的生态巨债,看到了这种疏忽背后的种种因果链条,看到了走出困境走向希望的唯一之路。作为前奏,本刊新年1月号已先刊发了姜春云同志为该书写的序言,本篇以解读的方式对全书的内容进行隆重推介。限于篇幅,所作的解读也只能蜻蜒点水。但作为一个推介者,本刊希望所有关注中国未来发展的人,能够挤时间坐下来读读原著,让这束穿越历史的理性之光也穿越你的心灵.引导你真切地洞察我们的过去.现在及将来。 相似文献
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缅甸:近期,柚木的需求量依然很大,而且等级较高的柚木原木的供应量有所减少。结果导致市场中等级较低的柚木销量增长。由于价格较低及使用范围广泛,4等锯材原木是最受欢迎的等级。一些较高等级的锯材和单板可以从4等锯材原木中获得。价格随柚木等级不同而稳步的下降。价格取决于可用森林的面积、可用原木的数量和等级及汇率等因素。 相似文献
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黑河地区毛赤杨的种子雨和种子库的观察 总被引:1,自引:0,他引:1
对黑河地区阔叶树种毛赤杨的种子雨和种子库进行了观察,结果显示:毛赤杨种子雨过程从每年8月25日到9月21日,其中9月1~7日是集中落果期,落果数量占总数的45.7%。霉烂是造成毛赤杨种子库亏损的最主要因素,霉烂果实的数量达到总量的96.4%。毛赤杨种子的自然萌发率低,仅为0.05%。 相似文献
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苦槠(Castanopsis sclerophylla (Lindl.) Schott.)为壳斗科(Fagaceae)栲属(Castanopsis (D. Don.) Spach.)植物[1],是亚热带地区常绿阔叶林的重要建群树种,也是亚热带常绿阔叶林次生演替阶段重要的先锋树种,对群落的组成、外貌、功能等都有一定控制作用[2].苦槠作为优良多用途树种,其生态效益、经济价值、食品保健功用及其在园林绿化中的地位已逐渐得到认可[3-4].目前,国内对苦槠的研究已有了一定基础,但对苦槠种群遗传学研究较少.种子是物种遗传变异的重要特征之一,在分类和遗传上具有重要的价值[5],种子形态不仅决定其扩散能力,也影响到种子的萌发和幼苗定植,进而影响到种群的分布格局[6].研究苦槠种子性状变异及其地理分化,对了解苦槠种群遗传分布格局具有重要意义,进而也可为苦槠天然林的保护和人工林的营建提供理论参考. 相似文献
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Assessing the characteristics of seed supply will be vital to better understand the dynamics of forest regeneration. In this study, we surveyed the aboveground vegetation, the seed rain, the seed bank, and natural seedling emergence in four typical 24-year-old plantations (eucalyptus, mixed-native, mixed-legume, and mixed-conifer) and a naturally successioned shrubland in southern China. The dominant species in the understory were similar among the five plant communities. The seed rain and the seed bank were dominated by shrubs and herbs but indigenous tree species were rare. Species that were common to all five-plant communities represented a great proportion of the seeds in the seed rain and seed bank. The seed rain consisted mostly of seeds derived from the local plant community. Seed abundance was greater in the seed bank than in the seed rain, and species richness was greater in the seed bank and in the corresponding plant community than in the seed rain. Species composition similarity between the seed rain, the seed bank, and the aboveground vegetation was low, because the seed rain contained much fewer species, and the seed bank and aboveground vegetation contained many different species, respectively. These findings indicate that both the seed rain and the seed bank play important roles in providing seeds for plant recruitment in the understory, but the seed bank contributes more than the current seed rain to the diversity of recruited plants. The current plant community has little impact on the qualitative composition of the seed rain and seed bank. Based on these data, it appears that succession to the desired zonal, mature forest community is unlikely to result from seeds in the seed rain or seed bank. Lack of seed availability of desired zonal mature forest species is the main bottleneck currently limiting succession in the plantations. Reintroduction of late-successional species could facilitate the desired succession. 相似文献
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比较分析两种不同麻疯树种源种子发芽率、发芽势、发芽速度、发芽指数、发芽条件以及外观品质,结果表明:种源、种壳、种质、湿度、氧气以及种子前处理影响了种子发芽率、发芽势、发芽速度、发芽指数;破壳比未破壳的发芽效果好,种源A比种源B种子发芽率高,发芽期间应保持一定的湿度和通气条件,前期的消毒、浸种也是必需的环节。 相似文献
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不同种源千年桐种子质量差异性研究 总被引:1,自引:0,他引:1
千年桐是我国特有的工业油料树种,具有良好的速生抗寒特性,可作为用材树种在温度较低的区域有良好的开发潜力,并且有发展为生物质能源林的潜力。本文针对不同种源千年桐种子特性进行了初步研究。结果表明:建阳市内种源千年桐种子重量和净度均存在差异,徐市种源千粒重最高(3 752 g/千粒),漳墩种源净度最高(98.6%)。不同县域种源千年桐种子重量和净度亦存在差异性,顺昌种源(4 223 g/千粒)和尤溪种源(4 186 g/千粒)的种子重量较其他种源有较为明显优势,政和种源净度最高(99.08%),不同种源千年桐种子重量和净度之间相关性不显著。 相似文献
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Seed deterioration is an irresistible physiological phenomenon.The aim to studyseed deterioration is to see if seed deterioration can be retarded artificially and the higher seedvigor of fine varieties be maintained.The change of seed deterioration occurs in almost every sys-tem,and affects many kinds of enzyme and almost all organelle,as a result,the seed loses its vig-or.The reason of seed deterioration and the lost of seed vigor are mainly studied and discussed inthis paper.According to the external and internal two kinds of theory advanced by E.H.Roberts,Much deep discussions are made from the view of biochemistry. 相似文献
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种苗检测是评定林木种苗质量的重要手段 ,根据《种子法》及新标准对种苗检测的要求 ,在分析种苗检测现状与存在问题的基础上 ,提出种苗检测的调整思路 相似文献
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Forty-two percent of the land area in the neighbouring districts (kapubatens) of Wonogiri, Central Java and Ponorogo in East Java is covered with secondary forests of naturalized exotic tree species that are common components of governmental land rehabilitation programs. The seed suppliers operating in the Wonogiri–Ponorogo area represent only 9% of the suppliers in Indonesia yet they account for 80–90% of the national tree seed supply capacity. Wonogiri–Ponorogo suppliers procure and sell 1,510 tons of seed annually. About 24% of this (362 tons) is exchanged between suppliers, 1,148 tons are sold to customers across Indonesia, and less than 1 ton is exported. About 72% of the seed sold (826 tons) is collected in the Wonogiri–Ponorogo area, the remainder originating in Sumatra, Madura and Nusa Tenggara. In Wonogiri–Ponorogo, tree seeds are collected by farmers on contract with seed assemblers or seed companies. Assemblers link farmer collectors with seed companies and middlemen, who sell seed to customers. Government agencies purchase 75% of the seed. Cover crop species, Gmelina arborea, Tectona grandis and Leucaena leucocephala account for the 85% of the total seed sold. The sheer volume of seed collected in Wonogiri–Ponorogo assures that it comes from a large number of unrelated trees over widely dispersed locations. However, research results indicate individual farmers collect seed from a limited number of adjacent trees. Experience indicates simple seed collection guidelines help farmers improve their seed collection practices and the genetic quality of seed collected. A commitment to seed quality by all agents involved in the seed trade and customers is required to make such guidelines functional and acceptable. Seed procurement and diffusion generate significant income for all seed agents. As the dominant agents who facilitate most of the activities and inputs required to move seed through the pathway from forests to customers, seed companies receive the most financial benefits. Farmer seed collectors are the most numerous agents in the seed pathway, with an estimated 22,500 farmers involved in seed collection activities annually. Farmer families living near seed companies earn additional income by processing seed. 相似文献
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川西南山地高山栲种群种子雨和地表种子库研究 总被引:5,自引:0,他引:5
研究川西南山地区两个高山栲低密度种群的种子雨模式、种子雨过程中地表种子库动态和种群的幼苗状况,讨论种子产量、种子存留和种子对成苗的贡献.结果表明:1)种子雨持续时间超过2个月,但种子下落的高峰期存在样地间差异;2)该地区高山栲的种子产量很低,种子雨散落的密度不大(2.3~2.8个·m-2).3)在种子雨过程中,地表种子库各组成的动态不同,霉烂种子和萌发种子为零,完好种子和虫蛀种子有轻微的波动,完好种子的存留密度为0.13个·m-2;和它们相反,地表的壳斗和败育种子存在积累效应.4)动物捕食是地表种子损失的主要原因,两种群分别占91.3%和97.83%,地表种子的存留率仅为8.7%和2.17%.5)研究样地的高山栲种群低的种子生产量、地表种子存留率和幼苗建成困难等3个环节都限制了高山栲种群的实生更新. 相似文献