986 resultados para 2 Samuel 7


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土壤碳循环过程是目前全球碳源碳汇研究的核心,目前对土壤碳循环过程和机制的研究还十分缺乏。杉木人工林约占我国人工林面积的1/4,由于近几十年经营管理措施不当,土壤有机碳的下降已经成为不争的事实,极大地影响了杉木人工林生产力的可持续发展。本研究通过对杉木人工林土壤有机碳来源、分解和释放动态的区分量化,结合13C标记示踪试验,开展了杉木凋落物分解对土壤有机碳平衡影响的研究,为土壤碳平衡和转化机理及杉木人工林的可持续经营提供了可靠的理论依据。通过系统的研究,得出以下结论: ⑴估算了典型杉木人工林土壤碳的周转状况,研究发现典型杉木人工林土壤碳更新较慢。土壤碳年输入量、形成量、转化量、输出量和贮存量分别为2.79 t hm-2、1.58 t hm-22.04 t hm-2、4.57 t hm-2、113.21 t hm-2。其中在土壤碳年排放量中矿质土层呼吸、根呼吸、凋落物层呼吸碳分别占土壤碳总排放量的50.6%、26.0%、23.1%。 ⑵计算了凋落物分解对土壤碳平衡的贡献。不同器官凋落物在土壤中的矿化释放碳量和进入土壤碳库量均随着凋落物易分解性的增大而增大,并且各器官凋落物分解以CO2-C释放最多,以微生物量碳存在的量次之,以可溶性碳存在的量最少。年均温16.5 ℃条件下培养100天,分别来自于叶、枝、细根、粗根有机碳的13.81%、9.26%、5.74%、4.62%被矿化释放,占总CO2-C释放量的比例分别为43.7%、37.2%、31.9%、29.0%。同时不同器官凋落物依次有3.05%、3.26%、2.24%、1.84%存在于土壤微生物碳库,占总微生物量碳的比例分别为12.9%、14.3%、10.5%、8.8%;不同器官凋落物依次有0.62%、0.62%、0.31%、0.24%存在于可溶性有机碳库,占总可溶性有机碳的比例分别为3.99%、4.10%、2.13%、1.73%。 ⑶不同器官凋落物进入土壤对土壤碳排放的激发效应不同,叶、枝、细根、粗根加入土壤产生了正激发效应,激发率依次为6.6%、7.0%、2.2%、2.8%。并且土壤风干-湿润过程影响了凋落物在土壤中的分解和转化过程。土壤风干-湿润使起始矿化底物库增大,培养初期凋落物分解速率上升,同时土壤原有机碳矿化速率降低,微生物对凋落物碳的利用以及凋落物对可溶性有机碳的贡献下降。 ⑷凋落物碳在不同轻组密度组分中的分布不同,但各器官凋落物间无明显差异,均为中等密度自由轻组最多,其次为最小密度自由轻组,最少为闭蓄轻组。室外培养224天,结果表明叶、枝、细根、粗根凋落物在各密度组分中的分配情况为:<1.0 g cm-3自由轻组中16.5~19.1%,1.0~1.8 g cm-3自由轻组中56.8~65.2%,闭蓄轻组中残留5.7~6.9%,其余的9.9~21.0%被矿化损失。研究还表明,凋落物粉碎添加方式能改变其在土壤组分中的分布比例,倾向于向较重的密度组分中分布而被保护起来利于有机碳的积累。

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近年来,土壤重金属污染的植物修复得到世界各国的重视,将花卉植物应用于污染土壤修复方面的研究应该说是刚刚兴起,但具有巨大的修复潜力。我国的铅污染形势十分严峻,大量的铅污染土壤亟待修复。铅在土壤中生物有效态的含量很低,因此必须采用一些有效的强化手段(如施用螯合剂)来提高植物的修复效率。 本研究以草本花卉为研究对象,通过室外盆栽筛选实验,分析了30 种花卉植物对Pb 的耐性特征和积累特性,并与螯合诱导技术相结合,强化花卉植物的修复效果,同时尽量减少可能造成的环境风险和健康危害。 根据超积累植物应具备的4 个基本特征,对参试的30 种花卉植物进行盆栽初步筛选分析。实验结果表明,对Pb 污染耐性较强且积累能力较强的花卉有9种;对Pb 污染耐性较强但积累能力较弱的花卉共12 种,这些植物在植物稳定修复方面可能有一定价值;其它9 种花卉对Pb 污染耐性较弱且积累能力较弱,是Pb 的非超积累植物。 盆栽浓度梯度筛选实验表明,满天星和火炬鸡冠是具有铅超积累植物特征的花卉。满天星转移系数大于1,地上部铅含量超过了铅超积累植物需要达到的临界含量标准,但对高浓度铅污染耐性较差且富集系数小于1;火炬鸡冠耐性较强且地上部铅含量超过了铅超积累植物需要达到的临界含量标准,但转移系数和富集系数均小于1。 水培实验表明:EDTA、NTA 强化效果较好;矮牵牛幼苗土培强化实验确定:先加EDTA,一周后加入NTA,且二者的比例为2:1 时修复效率最高;在7 种铅积累能力较强的花卉植物成熟后,收获前按上述方法分两次施加混合螯合剂,实验结果证实此修复方法具有有效性、经济性、安全性和公众可接受性。

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生态资产评估是近年来备受关注的一项工作。长期以来,由于受资源无价、环境无价观念的影响,生态资产评估的各个环节目前来看都不是很成熟。虽然这方面的社会需要非常紧迫,但可操作的评价方法及指标体系却无法满足社会的需求,许多认识也很不清晰和一致,因此,开展此项工作就显得非常迫切和重要。 本文拟在已有工作的基础上,就生态资产的理论和实践两方面面临的问题进行探究。理论上,综合分析、归纳、凝炼和完善前人的研究工作,对生态资产评估所研究的内容和具体的测算方法进行了阐释。借鉴自然资本理论和森林资源核算理论等已有成果和方法,提出较为完善的生态资产评估理论和可操作的评估方法。选择长白山林区露水河林业局为典型案例,基于森林资源清查数据,在实地调查和对相关大量文献综合分析的基础上,从生态系统质量、生态系统压力和生态资产价值量三方面进行了具体测算。获得以下主要结论: (1)生态资产评估可以从生态系统质量、生态系统压力和生态资产价值量三方面着手,由于生态系统的复杂性,目前看来,评估的精确性不应是首要目的,而评价方法及结论的科学与合理性、能否产生较强的说服力和警示作用才是关键。 (2)构建了操作相对简单,容易理解的生态系统质量评估指标体系。选用综合指标法,初步得出长白山林区露水河林业局的生态系统质量指数为0.6,说明该地区生态系统质量有待提高。 (3)运用生态足迹指数来反映区域生态系统所受压力的程度,计算得生态足迹指数为0.638,表明该区具有弱可持续发展能力,也反映了长白山林区露水河林业局森林生态系统所受外力需要减轻。 (4)运用传统的测算方法,结合社会发展阶段系数,选择并测算了林木,林副产品,碳储,涵养水源,生态旅游等5个方面的资产价值。长白山林区露水河林业局生态资产的总量为180.2亿元,人均拥有生态资产约为35.7万元。其中有形生态资产为23.5亿元,无形生态资产为156.71亿元,无形生态资产是有形生态资产的6.67倍,由此足见加强生态保护的重要性。

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本文通过对辽西地区现有的47.1万hm~2油松林的广泛调查研究,探索出油松纯林结构调整的三种模式,即:人促更新调整模式(I)、镶边补空调整模式(II)和带状皆伐改造调整模式(III)。首次提出了辽西地区油松林结构调整全理林分油松所占的比例、皆伐带的宽度、镶嵌斑块的面积等数量指标。即当油松纯林集中连片的面积在10-15hm~2以上时,应进行调整;调整时,油松所占的最适比例为35%左右;在实行III模式调整时,最适带宽为12-30m,有时可加大到50m;实行II模式调整时,油松镶嵌斑块的最适面积为1-3hm~2左右,砍伐的油松斑块面积在 3hm~2以下。油松纯林经调整后,其林分的水源涵养能力、土壤肥力状况、林木生长量、抗虫效应、物种多样性等都有较大改善,尤其是固 N 树种的应用,效果更加明显。调整后的林分与油松纯林比可增各种效益达 7.4万元/hm~2·a。

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用百喜草(Paspalum notatum)和水花(Alternanthera philoxeroides)等草本植物作对比,通过叶片离体实验、温室盆栽实验、田间小区实验和大田推广实验,并结合室内分析,较系统地研究了香根草(Vetiveria zizanioides)的抗热、抗冻和抗盐特性和对污水的净化效果。此外,还探讨了矮化香根草和促进香根草分蘖的可能性;提出了香根草生态工程的思想,阐述了香根草生态工程推广应用的价值与效果;通过对国内野生香根草资源的调查和标本鉴定,指出了过去对这个种的错误描述,提出了保护野生香根草资源和香根草湿地的紧迫性与重要意义。主要研究结果如下: 1.离体叶片电解质渗漏的测定结果表明,3种植物对高温、冻害、干旱的抵抗力依次为香根草 > 百喜草 > 水花生,特别是在胁迫程度高、幅度大或胁迫时间长时,香根草所表现出的强抗逆性更加明显。香根草有比百喜草和水花生更强的适应能力。2.叶片电导率的实验结果显示,香根草、水花生和百喜草对盐胁迫的反应相差不明显,但盆栽实验则显示出较大差异,抗盐能力明显表现为香根草 > 水花生 > 百喜草。导致3种植物生物量下降10%的EC_(se)值分别为6.4、5.1和4.3 dS m~(-1);导致生物量下降50%的EC_(se)分别为20.9、16.2和11.5 dS m~(-1)。在抗盐等级划分上,香根草和水花生属抗盐植物种类,百喜草属中度抗盐种类。总的来说,3种植物都表现出了相对较强的抗盐特性。以上结果还表明考察植物的抗盐性时必须用整株做为实验材料,离体叶片或组织培养所得到的结果不能作为植物抗盐能力的标准。3.植物体内Na~+和Cl~-含量随土壤盐度水平升高而升高,而茎叶中的Na~+和Cl~-又直接影响到植物的生物量、叶面积、株高等。这表明盐度对3种植物生长发育的影响相当明显,且植物体的Na~+和Cl~-很可能都是影响植物生长发育的直接因子。然而,叶片光合色素受Na~+或Cl~-的影响不甚明显,而且在Na~+和Cl~-的浓度不高时色素含量还随茎叶中Na~+和Cl~-的浓度升高而显现增加趋势,即使Na~+和Cl~-的浓度较高时,光合色素下降的幅度也远不及生物量的大。这可能由于光合作用是被“反馈抑制”,而不是直接被Na~+或Cl~-抑制。4.3种植物表现出完全不同抗盐机理。香根草表现出拒盐特性,而且将所吸收的盐分的大部分(尤其是Na~+)滞留在根系内:水花生表现为稀盐特性,即当植株体内含盐量增加时,其水分含量亦增加,并趋向肉质化;百喜草有较强的吸盐能力,并可能通过盐腺泌出体内高浓度的盐分且通过加速老叶死亡来排除过多的盐。5.广州市李坑垃圾卫生填埋场的渗滤污水含有高浓度的污染物,经过人工净化后仍未 达到排放标准,对植物产生毒害并带来严重的环境污染,须作进一步净化,并建议开展生物净化来辅助物理和化学净化。6.在被观测的4种植物中,风眼莲(Eichhornia crassipes)在高浓度和低浓度2种污水中均被毒害致死;百喜草在高浓度的渗滤液中不能存活,在低浓度中受严重伤害;水花生在高浓度污水中受较重伤害,但在低浓度形成庞大生物体,这可能是污水的“富营养化”所致;香根草在这2种污水中亦受伤害,但受害程度为4种植物中最轻。总的来说,它们的抗污能力和去污效果表现为香根草 > 水花生 > 百喜草 > 风眼莲。7.在污水中表现相对较好的2种植物中,水花生对低浓度污水的净化效果总体上好于香根草,尤其对总氮和硝态氮的净化效果明显好于香根草,但香根草对高浓度污水中的7种“污物”的净化效果均优于水花生,且对低浓度污水中的磷与COD的净化亦优于水花生。在被观测的7种水质指标中,植物对氨氮的净化效果最好,净化率在77%~91%之间。此外,香根草对磷也表现出了较强的净化能力,净化率高达70%以上。香根草和水花生可分别作为高、低2种浓度垃圾污水的净化植物来辅助净化污水。8.香根草虽不是水生植物,但能在水中生长。用香根草作为污水的净化植物时须用支撑物将其固定;香根草和水花生都生长迅速,生物体高大,因此用它们净化被污染的环境时,还应适时对其地上部分进行剪割以保证新生的植株体能不断地吸收水中“污物”,使它们都能成为“超级生物累积器”。但是,任何单一植物对污水或污物的净化能力都是有限的,要想对垃圾污水产生好的净化效果,最好的办法也许是将香根草、水花生等多种有良好净化效果的植物有机结合起来,同时种植在污水中。9.植物通过吸收来去除“污物”的能力是很有限的。香根草和水花生对污水中N、P、Cl~-的吸收量只占净化量的一部分,和原液中N、P、Cl~-的含量相比,吸收量所占的比例更低。植物净化系统中的去污方式除根系的吸收作用外,还有根系的吸附、元素的沉降、固结和挥发、水体中微小动物和微生物的作用等,即是通过根系微生态系统的综合作用来达到净化目的。10.植物生长延缓剂对香根草的株高生长、分蘖速度和抽穗开花等方面都产生影响,但不同的药剂种类和浓度所产生的影响相差甚远。低浓度的延缓剂不仅不抑制香根草的株高生长,而且还有显著地促进作用,高浓度虽有抑制作用,但这种抑制也只是短期的,一般不超过2个月。延缓剂对分蘖的形成具有较好的促进作用,而且这种促进作用持续3个月左右。3种延缓剂中,以低浓度的B9促进分蘖的效果最显著,比对照高出50%。不同的延缓剂对香根草抽穗扬花的影响表现不同,PP333具有一定的促进效果,而CCC和B9-尤其是B9-表现出明显的抑制作用。总的来说,B9对香根草矮化、促进分蘖和抑制开花方面产生的效果要好于CCC和PP333。11.植物生长延缓剂对香根草的作用效果与对一般作物的作用效果相差较远,这可能是香根草的抗性较强,延缓剂对它的影响不明显所致。总的来说,植物生长延缓剂对香根草株高生长的抑制效果不理想。有关这方面的研究还有待进一步开展。12.公路滑坡不仅带来严重的交通阻塞,而且危及到行车与行人的安全。常规治理公路滑坡的手段是采取砌石墙的工程措施,这不仅费用昂贵,而且缺乏生态效益,也难以达到根治效果。应用香根草生态工程(The Vetiver Eco-engineering)对滑坡路段进行综合治理,能产生良好护坡固土效果,而且所需成本仅为机械工程的12%~18%。香根草生态工程是指以香根草为主要或核心草种,同时与一些适合当地生长的植物—包括乔木、灌木、草本、藤本一进行有机搭配,并在需要时辅以一定的工程措施,用于水土流失治理和退化生态系统的恢复的植物生态工程措施。13.为了使香根草生态工程尽快生效,应采取一定的栽培管理措施。香根草应等高密植,注意施肥,前期不要被遮光;所搭配的植物应该是抗逆性强,乔、灌、草、藤结合起来,并注意在香根草带中间适当种植一些生长迅速、抗瘠能力强、覆盖效果好的草本植物,这不仅能使坡面更稳固,而且能变得更美观。总之,香根草生态工程在公路护坡方面所产生的经济效益、社会效益和生态效益都是相当明显的,在我国南方地区有着广阔的应用前景。14.一般认为,香根草原产印度,然而,中国亦有天然的香根草群落分布。早在70多年前就在海南发现野生的香根草种,1957年又在广东吴川发现一片面积达6000多hm~2的湿生性的天然香根草群落。40年来,这片珍贵的热带湿地遭到严重破坏,香根草的面积和密度都大幅度下降。对此,笔者建议尽快在当地划一块自然保护区,这不仅是为了保护珍贵的野生香根草资源,保护当地的生物多样性和生态环境,而且能为研究热带湿地和草原提供理想基地,并为研究香根草的起源、系统演化和分类提供理想素材。15.过去的文献一直把广东吴川这片湿地中的野生香根草种认为是V. nigritana,但本文的标本鉴定认为它并不是V. nigritana或其它种,而是V. zizanioides。不过,引种栽培观测和RAPD技术研究都表明,这一野生种和普通的栽培种属于同一个种的不同生态型或基因型,而导致形成这种差异的原因是由于野生种生长在长年渍水或干湿交替的环境所致。16.目前对香根草的起源和系统演化知之甚少,香根草属的系统分类还很不完善,有 关香根草对重金属、污染物的抗性机理等诸多方面都还不太清楚或很不清楚。因此,对 香根草这一神奇植物的研究还有待继续深入地开展下去。总之,香根草这一多年生的禾本科植物对盐、碱、酸、瘦、冷、热、早、涝都表现出了较强抗性,在水土流失防治、退化生境恢复、污染环境净化、贫瘠土壤改良、农田小气候改善等方面都表现出了较好效果。香根草无愧是一种神奇之草。然而,要真正将香根草生态工程在我国南方地区大规模推广开来,还需要做较多的工作,这包括更深一步的科学研究、更广泛的宣传、培训与示范、更充分的资源利用与经济创收等。

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对辽西半干旱区褐土农田施用几种保水剂的效果进行了室内模拟和田间试验研究.观测了保水剂包衣和沟施对春小麦出苗、土壤水分含量及产量的影响,对使用保水剂的适宜浓度、效果、经济效益进行了评价,并对保水剂促进出苗的机理和田间保水机制进行了探讨.结果表明,保水剂包衣能够加快种子吸水过程,促进春小麦萌发出苗,出苗期提前1~2天,出苗率提高6.5%~11.5%,增产7.5%~12.7%,投入产出比为1:7.保水剂包衣的适宜浓度为1%,浓度过大(≥5%),保水剂层过厚,会影响种子呼吸和水分通过,不利于出苗,出苗率和产量分别提高5%和10%以上.保水剂沟施,可提高土壤持水能力,0~30cm的土壤水分含量,提高了1个百分点.保水剂沟施处理,水分利用效率可提高0.72.0kg·mm<'-1>·hm<'-2>,提高幅度为6.7%~18.5%.研究发现,保水剂田间保水效果,与土壤含水量有关,土壤水分低于毛管断裂含水量时,保水剂对蒸发速率影响很小.

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本文系统研究了沈阳城市森林的布局与结构、城市森林功能、城市森林病虫害发生与树木健康状况和城市自然资源与社会经济状况等指标对沈阳城市森林生态系统健康与管理的影响。同时一,采用2种生态系统健康评价方法对沈阳城市森林生态系统健康状况进行了评价,并提出了沈阳城市森林生态系统健康管理的对策。研究结果如下:1、截至2004年末,沈阳城市森林植被覆盖率已经达到35%,城市森林林地分布基本合理,但需要进一步加强道路林地、居住区林地和城郊大面积生态林建设。2、沈阳城市森林以乔木为主,乔灌株数比为1.7:1,乔灌的覆盖度比约为7:1。3、沈阳城市森林不同类型林地中植物组成不同。公园林地中有74个属,137个种(变种);庭院林地中有53个属,104个种(变种);居住区林地中有45个属,81个种(变种);道路林地中有43个属,94个种(变种);运河风景林地中有75个属,142个种(变种);棋盘山风景林地中有48个属,118个种(变种)。4、公园林地、庭院林地、居住区林地、道路林地和运河风景林地的Shannon一Wiener多样性指数分别为2.78、3.05、3.15、3.18和3.18,均匀度指数分别为0.56、0.66、0.72、0.70和0.64。除了棋盘山风景林地外,沈阳城市森林中栽植总量超过乔木总量5%的乔木树种有7个属,分别为李、柳树、杨树、桧柏、榆树、槐树和银杏,7种树木总量达到了全部乔木总量的82.09%;栽植总量超过灌木总量5%的灌木树种也有7个属,分别为水腊、丁香、李属,小聚、玫瑰、忍冬和连翘,7个属灌木总量达到了全部灌木总量的87.92%。5、公园林地、庭院林地、道路林地和防护林地中OBH<20cm、20cm<DBH<60cm和DBH>60cm树木的比例分别为:57.9%、40.0%、2.1%,49.2%、47.8%、3.0%,65.3%、33.1%、1.6%和64.6%、34.9%、0.5%,表明沈阳城市森林树木的规格总体上偏小。6、经样方调查和CITYgreen模型计算,沈阳城市森林的生态效益约2.0亿USD/yr.。公园林地、庭院林地和风景林地的景观指标相对较高;道路林地和居住区林地的景观效果一般;防护林地的景观效果较差。7、目前已经发现的沈阳城市森林病害约600余种,虫害约700余种,其中杨树主要病虫害39种,柳树的主要病虫害有33种,榆树和槐树的主要病虫害均为,1种。杨柳树腐烂病、光肩星天牛、天幕毛虫、桃红颈天牛和美国白蛾等是近10年来沈阳城市森林中普遍发生和造成严重危害的主要病虫害。沈阳城市森林主要树木的平均健康指数为2.68,处于一般健康状态。8、沈阳城市森林的土壤和水资源状况均不利于树木的健康生长,沈阳的社会经济发展也有待于进一步提高。9、经过生物指示物法(光肩星天牛为生物指示物)、专家权重法、公众问卷调查和对比研究,沈阳城市森林生态系统总体上处于亚健康状态。10、通过对沈阳城市森林资源、管理状况的调查研究和健康状况的评价,本文提出了沈阳城市森林生态系统健康管理的对策,包括合理规划沈阳城市森林林地布局,增加道路林地、居住区林地和城郊林地的面积和植被覆盖率;调整树木种类组成,避免单一或少数树种的大量栽植,提高生物多样性水平;保护大树和古树;增加城市森林管理资金的投入;应用先进技术,采取科学的病虫害防治和植物养护方法,促进树木的健康生长等。This project systematically studied the urban forest ecosystem health and management in Shenyang. The study explored factors, such as urban forest structure, distribution, pests, aesthetic value, ecological benefit, natural resources and socieo-economic status, that affecting the urban forest ecosystem health and management. Two methods were used to evaluate the ecosystem health. This project also proposed Shenyang's urban forest ecosystem health management strategies. The research results can be summarized as follows: 1. As of the end of 2004, urban forest coverage in Shenyang is about 35%, and is in relatively even patch distribution pattern. However, the street trees and roadside forest patches, residential block forest patches should be enhanced. 2. Trees are the major component of the Shenyang s urban forest, followed by shrubs. The quantity ratio of tree to shrub is about 1.7:1, and the coverage ratio of trees to shrub is about 7:1. 3. Species composition varies by location. There are 74 genera, 137 species (including varieties) in the public parks; 53 genera, 104 species (and var.) in the green spaces of the institution (including school), factory, and company; 45 genera, 81 species (var.) in residential blocks; 43 genera, 94 species (var.) in streets and roadside forest patches; 75 genera, 142 species (var.) in the Canal landscape forest patches; 48 genera, 118 species (var.) in the Qipan Mountain recreation forest. 4. The Shannon-Woener indices varies in parks, in institution, factory, and company yards, in streets and roadside forest patches, in residential blocks.there are 2.78, 3.05, 3.18, 3.15, 3.18, respectively; and the evenness indices are 0.56, 0.66, 0.70, 0.72, 0.64, respectively. Besides the Qipan Mountain forest patches, trees of 7 genera, Prunus spp., Salix spp., Populus spp., Sabina spp., Ulmus spp., Robinia spp. and Ginkgo biloba are of more than 5% the total urban trees, respectively. In fact, trees from these 7 genera are about 82% of all trees in Shenyang's urban forests. In terms of shrubs, species of 7 genera, Ligustrum spp., Syringa spp., Prunus spp., Berberis spp., Rosa spp., Lonicera spp., and Forsythia spp. are more than 5% the total urban shrubs, respectively. 88% of all the shrubs in Shenyang s urban forest are from these 7 genera. 5. The diameter class of DBH<20cm, 20cm60cm of trees in parks, in institution, factory, and company yards, in in streets and roadside forests, and in protective forests are 57.9%, 40.0%, 2.1%; 49.2%, 47.8%, 3.0%; 65.3%, 33.1%, 1.6%; and 64.6%, 34.9%, 0.5%, respectively. The result indicated that the DBH is relatively small in Shenyang s urban forests. 6. Using random plots sampling and CITYgreen model calculation, the ecological benefit of Shenyang's urban is about 0.2 billion US dollars per year. The aesthetic value of parks, institution and company yards, and scenary forest patches is relative high; however, the aesthetic value of protective forest patches is low. 7. There are more than 600 types of diseases and more than 700 kinds of insects in Shenyang's urban forest. Among them, Populus spp., Salix spp., Ulmus spp. and Robinia spp., are attached mainly by 39, 33, 11, and 11, difference types of pests respectively. The rot disease of the Populus spp. and Salix spp., and the insects such as, Anoplophora glabripennis, Malacosoma neustria, Aromia bungii, and Hyphantria cunea are major pests in Shenyang s urban forest for the past 10 years. The trees health condition is relatively poor by having the average health index of 2.68 for major species. 8. The urban soil and water resource are not favorable to tree's growth in Shenyang, and so is the socieo-economic status. 9. Through using bio-indicator, professional and public evaluation, and comparision with other urban forests, it can be concluded that the status of Shenyang s urban forest is not very healthy in general. 10. To improve the urban forest ecosystem health in Shenyang, a better urban forest design need to be implemented to enhance the area and vegetation coverage of the street and roadside forests, the residential block forests, and the surburb forest Species biodiversity need to be enhanced by adjust the species composition of urban forest trees to reduce the single or several tree species populations and to plant more varieties. A better fundings for urban forest health management need to be budgeted. Advanced technologies in tree care and scientific measures to control pests need to be adopted to prove better care for plants and to keep trees grow healthfully.

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本文建立了一个针对温带针阔混交林生态系统的碳循环模型,并就长白山阔外红松林不同林型进行了验证工作。模型具有17个状态变量,采用按日的环境条件以进行按日的碳循环模似。本模型主要具有下列特点:(1)引入了光营养面积概念,从而使得在混交林中可应用日总光合公式。(2)采用了不同树种净初级生产分配方案不同的方法解决了净初级生产物的分配问题。(3)对于木质的呼吸量采用了直径与相对呼吸率的双曲关系。本文一个重要结论是从逐月的碳循环模似结果可得到红松阔叶林于7-8月份达到最大生产量,这可能有助于人们对阔叶红松树采取较优的抚育措施。

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本学位论文报道了作为传统藏药材广泛使用的西藏产雪莲花化学成分的研究。论文由五章组成,第一章是三种西藏产雪莲花的化学成分的系统分离纯化和结构鉴定;第二章为西藏产雪莲花化学成分的液-质及串联质谱联用分析;第三章提出了以HPLC和TLC为检测方法的雪莲花药材质量标准草案;第四章给出了对西藏产雪莲花挥发油化学成分的气-质联用分析结果;第五章概述了雪莲花的化学成分及药理研究进展。 第一章包括三个部分。第一部分报道了绵头雪莲花(Saussurea laniceps Hand.-Mazz.)全草乙醇提取物化学成分的分离鉴定。采用正相硅胶柱层析及凝胶柱层析等分离方法,从西藏产绵头雪莲花的乙醇提取物中共分离鉴定出15个化合物。其中11个化合物为首次从该植物中分离得到,当中2个化合物系在凤毛菊属植物中首次发现。第二部分报道了水母雪莲花(Saussurea medusa Maxim.)全草乙醇提取物的化学成分。采用正、反相硅胶柱层析及凝胶柱层析等分离方法,共分离鉴定出15个化合物,其中1个为新化合物,另有4个化合物为首次从该植物中分离得到。新化合物结构通过质谱和一维及二维核磁共振等波谱解析方法及碱水解反应确定为巴豆酰基-高车前苷(M-7)。第三部分报道了三指雪莲花 (Saussurea tridactyla Sch.-Bip. ex Hook. f.)全草乙醇提取物的化学成分。采用正相硅胶柱层析及凝胶柱层析等分离方法,共分离鉴定出7个化合物,其中1个化合物为首次从该植物中分离得到。 第二章也包括三个部分。首先是采用液-质联用(HPLC-DAD-ESI-MSn)分析方法,对7个西藏不同产地的三指雪莲花化学成分进行了分析,通过与标准品的 UV和MS数据比较,共鉴定出14个峰,并对其中8个共有成分进行了定量测定。其次是关于八种西藏产雪莲花化学成分的液-质联用(HPLC-DAD-ESI-MSn)分析,通过与标准品的UV和MS数据比较,共鉴定出15个峰,并对其中8个共有成分进行了定量检测。最后通过对八种西藏产雪莲花主要化学成分的多级串联质谱(ESI-MSn)分析,快速、灵敏地鉴定出10个黄酮和3个香豆素化学成分。 第三章同样包括三个部分。首先是以绵头雪莲花中主要香豆素成分东莨菪素和伞形花内酯为对照品,通过TLC定性检测和HPLC含量测定,草拟出较严谨的药材质量标准。其次是将绵头雪莲花、三指雪莲花和雪兔子作为一个药材看待,草拟了以东莨菪素和伞形花内酯的TLC检测为指标的药材质量标准。最后是针对水母雪莲花,以主要黄酮成分芹菜素-7-O-b-D-葡萄糖苷为对照品作TLC检测,并草拟出该药材的质量标准草案。 第四章报道了西藏产雪莲花挥发油的化学成分分析。采用传统水蒸气蒸馏法分别从八种雪莲花全草中提取挥发油,利用气相色谱-质谱联用技术分别从水母雪莲花、绵头雪莲花、槲叶雪莲花、云状雪兔子、拉萨雪兔子、小果雪兔子、雪兔子和三指雪莲花中分别鉴定出83、83、56、34、21、20、24和20个化学成分,分别占其挥发油总量的70.7%、76.0%、82.2%、55.4%、49.7%、70.4 %、76.2%和 76.7%。 第五章为综述,总结和概括了雪莲花的化学和药理研究进展。 The dissertation reports the investigation of the chemical constituents of the genus Saussurea. Quite a lot of species in this genus are traditional Tibetan medicinal plants, and hence have been widely used in traditional Tibetan medicine. This dissertation consisted of five chapters. The first chapter is on the chemical constituents of three Saussurea plants. The second section is about the analysis of chemical constituents of Saussurea plants using HPLC-MS and ESI-MS/MS. In the third chapter, we proposed quality-control standards for the Genus Saussurea based on TLC (thin layer chromatography) and HPLC. The fourth chapter is about chemical compositions of the essential oil from the whole plant of Saussurea plants. The last chapter reviews the research progress of the Genus Saussurea. The first chapter consists of three parts. The first part is about chemical constituents of ethanol extracts from whole plant of Saussurea laniceps Hand.-Mazz. Fifteen compounds were isolated by column chromatography on normal phase silica gel and Sephadex LH-20. Among them, eleven compounds were isolated from this plant for the first time, and two compounds were isolated from Genus Saussurea for the first time. The second part is about chemical constituents of ethanol extracts from whole plant of Saussurea medusa Maxim. Fifteen compounds were isolated by column chromatography on normal phase, reversed phase silica gel and Sephadex LH-20. Five of them were isolated from this plant for the first time, and there is one new flavonoid glucoside which was identified as 6″-O-crotonoyl-homoplantaginin (M-7) based on the evidence of one- and two-dimensional nuclear magnetic resonance, mass spectrometry analysis, and alkaline hydrolysis reaction. The last part is about chemical constituents of ethanol extracts from whole plant of Saussurea tridactyla Sch.-Bip. ex Hook. f.. Seven compounds were isolated by column chromatography on normal phase silica gel and Sephadex LH-20. There is one compound which was isolated from this plant for the first time. The second chapter consists of three parts. In the first part, we analyzed the chemical constituents of S. tridactyla collected from seven different places in Tibet using HPLC-DAD-ESI-MSn. Fourteen peaks in the HPLC were identified by comparison of UV and MS spectra with those of authentic compounds, among which eight common peaks were quantified. In the second part, we analyzed the chemical constituents of eight Saussurea species using HPLC-DAD-ESI-MSn method. Fifteen peaks in the HPLC were identified by comparison of UV and MS spectra with those of authentic compounds and eight main peaks of them were quantified. In the last part, we analyzed the chemical compounds of the above eight Saussurea plants directly by ESI-MS/MS. Thirteen major compounds, including 10 flavonoids and 3 coumarins were easily rapidly identified. The third chapter consists of three parts. In the first part, we proposed a comparative high quality-control standard for S. laniceps, based on quality detection by TLC and quantity analysis by HPLC using two major compounds (umbelliferone and scopoletin) as standard compounds. In the second part, in viewing S. laniceps, S. tridactyla and S. gossypiphora as the members of one family of medicinal herbs, we suggested a quality-control standard based on the TLC detection of the two major compounds (umbelliferone and scopoletin). In the last part, we proposed a quality-control standard for S. medusa based on the TLC detection of its major component (apigenin 7-O-glucoside). The four chapter analyzed the chemical constituents of essential oil of eight Saussurea species. The essential oils were extracted from the whole plants of these samples with water stream distillation. By GC-MS analysis, we identified eighty-three compounds from S. medusa, eighty-three from S. laniceps, fifty-six from S. quercifolia, thirty-four from S. aster, twenty-one from S. kingii, twenty from S. simpsoniana, twenty-four from S. gossypiphora, and twenty from S. tridactyla respetively, which accounted for 70.7%, 76.0%, 82.2%, 55.4%, 49.7%, 70.4 %, 76.2% and 76.7% of the total essential oil, respectively. The last chapter reviews the research progress of the Genus Saussurea.

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本文对禄春安息香(Styrax macranthus)种子和攀援孔药花(Porandra scandens)全草的化学成分进行了研究,共获得30个化合物,其中2个为新化合物。 从禄春安息香种子95%乙醇提取物中分离并鉴定了12个化合物,其中2个新化合物鉴定为3-[7-methoxy-2-(3,4-methylenedioxy phenyl) benzofuran-5-yl] propyl 3-[7-methoxy-2-(3,4-methylenedioxyphenyl)benzofuran-5-yl] propanoate (1) 和去甲氧基-egonol-龙胆双糖甙 (2);已知化合物分别为2-(3,4-二氧亚甲基苯基)-5-甲酰基-7-甲氧基-苯并呋喃 (3)、egonol (4)、去甲氧基-egonol (5)、去甲基-egonol (6)、egonol-葡萄糖甙 (7)、egonol-龙胆双糖甙 (8)、egonol-龙胆三糖甙 (9)、豆甾醇 (10)、二十四烷酸 1-甘油酯 (11) 和胡萝卜甙 (12)。生物活性测试发现,化合物2具有促进雌激素E2合成的作用。 从攀援孔药花全草95%乙醇提取物中分离并鉴定了19个化合物:(2S,3S,4R)-2-[(2R)-2-羟基-二十一烷酰基氨基]-二十一烷-1,3,4-三醇 (13)、(2S,3S,4R)–2–二十四烷酰基氨基-十八烷-1,3,4-三醇 (14)、胡萝卜甙 (12)、β-谷甾醇 (15)、(20S,22E,24R)-5α,8α-表二氧-麦角甾-6,22-二烯-3β-醇 (16)、6β-羟基-豆甾-4-烯-3-酮 (17)、十六烷酸 1-甘油酯 (18)、桦木酸 (19)、大黄素 (20)、二十二烷酸 1-甘油酯 (21)、对羟基苯甲醛 (22)、十七烷酸 1-甘油酯 (23)、金色酰胺醇乙酸酯(24)、十九烷酸 1-甘油酯 (25)、棕榈酸 (26)、(E)-p-香豆酸 (27)、(22E,24S)-24-麦角甾醇-7,22-二烯-3β,5α,6β-三醇 (28)、2-去氧-β-蜕皮激素 (29)和auranamide (30)。 综述了近十年来发现的2-芳基苯并呋喃类新木脂素的结构特征、来源、生物活性和化学全合成。 Phytochemical investigation on the seeds of Styrax macranthus and the whole plants of Porandra scandens led to the isolation of thirty compounds, two of which were new ones. Two new 2-aryl benzofuran derivatives, 3-[7-methoxy-2-(3,4-methylenedioxy phenyl) benzofuran-5-yl]propyl 3-[7-methoxy-2-(3,4-methylenedioxyphenyl)benzo furan-5-yl]propanoate (1) and demethoxy egonol gentiobioside (2), were isolated from the 95% aqueous ethanolic extract of the seeds of Styrax macranthus, together with 7-methoxy-2-(3,4-methylenedioxyphenyl) benzofuran-5-carbaldehyde (3), egonol (4), demethoxy egonol (5), demethyl egonol (6), egonol glucoside (7), egonol gentiobioside (8), egonol gentiotrioside (9), stigmasterol (10), 2,3-dihydroxypropyl tetracosoate (11), and daucosterol (12). In vitro test, compound 2 promote the synthesis of estrogen E2. Nineteen compounds were isolated from the 95% aqueous ethanolic extract of the whole plant of Porandra scandens for the first time. Their structures were identified as (2S,3S,4R)-2-[(2R)-2-hydroxy-heneicosanoylamino]-1,3,4- heneicosanetriol (13), (2S,3S,4R)-2-tetracosanoylamino-1,3,4-octadecanetriol (14), daucosterol (15), β-sitosterol (12), (20S,22E,24R)-5α,8α-epidioxy-ergosta-6,22-diene- 3β-ol (16), 6β-hydroxylstigmast-4-en-3-one (17), 1-glycerol-1-hexadecoate (18), betulinic acid (19), emodin (20), 1-glycerol-1-docosoate (21), p-hydroxybenzaldehyde (22), 1-glycerol-1-heptadecoate (23), aurantiamide acetate (24), 1-glycerol-1- nonadecoate (25), palmatic acid (26), (E)-p-coumaric acid (27), (22E,24S)- 24-metbylcbolesta-7,22-diene-3β,5α,6β-triol (28), 2-deoxycrustecdysone (29), and auranamide (30). The characteristic, natural resource, bioactivity, and the total synthesis of 2-aryl benzofurans were reviewed.

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本论文由四章组成。第一、二和三章分别报道了双花千里光、川芎和宽叶羌活的化学成分研究。从三种药用植物中共分离和鉴定了40 个化学成分,其中8个为新化合物。第四章概述了藳本属植物及日本川芎的化学成分研究进展。 第一章包括三个部分。第一部分报道双花千里光(Senecio dianthus Franch.)地上部分乙醇提取物的化学成分。采用正、反相硅胶柱层析等各种分离方法,从中共分离出8 个艾里莫酚型倍半萜内酯,其中5 个是新化合物,并且有1 个为首次发现的连接了含氮原子取代基的艾里莫酚型倍半萜内酯。它们的结构经MS、IR、NMR及X-单晶衍射等解析方法确定为2b-angeloyloxy-10b-hydroxyeremophil-7(11)-en-8a,12-olide (1)、6b-angeloyloxy-10b-hydroxyeremophil-7(11)-en-8a,12-olide (2)、2b-angeloyloxy-8b,10b- dihydroxyeremophil-7(11)-en-8a,12-olide (3)、2b-angeloyloxy-8a-hydroxyeremophil-7(11),9(10)-dien-8b,12-olide (4)和8b-amino-10b- hydroxyleremophil-7(11)-en-8a,12-olide (5)。这8 个倍半萜内酯经体外生物活性测试表明均具有通过抑制巨噬细胞增殖抵制破骨细胞增生的活性。第二部分对艾里莫酚型倍半萜内酯的质谱裂解规律进行了初步探讨。第三部分报道双花千里光茎、和叶花的挥发油成分分析。采用传统水蒸气蒸馏法分别提取了双花千里光茎、叶和花的挥发油,用气相色谱-质谱联用(GC-MS)技术分别分离鉴定了其化学成分,从茎、叶和花挥发油中各分离和鉴定出70、80 和73 种化学成分,分别占挥发油总量的91.2%、85.7%及93.4%。 第二章包括两个部分。第一部分报道川芎(Ligusticum chuanxiong Hort.)根茎乙醇提取物的化学成分。通过正、反相硅胶柱层析等分离纯化和MS、NMR及X-单晶衍射等解析方法,共分离鉴定了21 个化合物,结构类型分属于苯酞、二聚苯酞、香豆素和脂肪酸类。其中2 个为结构比较新颖的二聚苯酞类化合物:chuanxiongnolide A (19)和chuanxiongnolide B (20),化合物19 的结构经X-单晶衍射得到确证。第二部分报道川芎挥发油的化学成分。采用不同的提取方法(溶剂萃取法、水蒸气蒸馏法、CO2 超临界流体萃取法)提取川芎挥发油,同时采集不同产地(四川彭县、四川郫县、云南鹤庆)及不同品质(川芎、奶芎、苓子)的川芎产品,利用GC-MS 技术分离鉴定其挥发油的化学成分,计算各成分的相对含量,并对比分析其中的异同。 第三章报道宽叶羌活(Notopterygium forbesii Boiss.)根茎化学成分的分离纯化和结构鉴定。通过正、反相硅胶柱层析等分离纯化和MS、NMR 等解析方法,共分离鉴定了13 个化合物,结构类型分属于香豆素、二氢异香豆素、甾体和羧酸类。其中1 个新二氢异香豆素类成分鉴定为6-methoxy-hydrangenol (37)。 第四章概述了藳本属植物及日本川芎化学成分的研究进展。 This dissertation consisted of four chapters. The former three chaptersrespectively elaborated the phytochemical investigation of three herbal medicines:Senecio dianthus Franch., Ligusticum chuanxiong Hort. and Notopterygium forbesiiBoiss.. Forty compounds, including eight new ones, were isolated and identified byspectral and chemical evidence. The fourth chapter elaborated the study progress ofchemical constituents of Ligusticum genus and Cnidium offcinale. The first chapter consisted of three parts. The first part is about the chemicalconstituents of ethanol extraction and essential oils from the aerial parts of S. dianthu.Eight eremophilenolides were isolated and identified. Among them, five ones are newcompounds and one of them is a novel eremophilenolide attched with an amino group.The structures of the new compounds were identified as 2b-angeloyloxy-10b-hydroxyeremophil-7(11)-en-8a,12-olide (1),6b-angeloyloxy-10b-hydroxyeremophil-7(11)-en-8a,12-olide (2),2b-angeloyloxy-8b,10b-dihydroxyeremophil-7(11)-en-8a,12-olide (3),2b-angeloyloxy-8a-hydroxyeremophil-7(11),9(10)-dien-8b,12-olide (4) and8b-amino-10b-hydroxyeremophil-7(11)-en-8a,12-olide (5) by spectral evidence andX-ray crystallography analysis. All the compounds were evaluated for theiranti-osteoclstogenesis activity using a proliferation inhibit assay with microphagecells. The second part elementarily discussed the characteristic fragmentation oferemophilenolides isolated from S. dianthus in ESI-MS.The latter part is about thechemical constituents of essential oil extracted from stems, leaves and flowers of S.dianthus with steam distillation. By the GC-MS analysis, 70, 80 and 73 compoundswere respectively isolated and identified which accounted for more than 91.2%, 85.7% and 93.4% of total essential oil. The second chapter, including two parts, is about the the chemical constituents ofethanol extraction and essential oils from rhizomes of L. chuanxion. In the first part, twenty-one compounds were isolated and iedntified. Two ones are novel dimericphthalides and the structures were suggested as chuanxiongnolide A (19) andchuanxiongnolide B (20) by spectral evidence and confirmed by X-raycrystallography analysis. In the second part, the samples were collected from differentextract techniques (solvent extraction, steam distillation and supercriticalfluid extraction), different habitats (Peng and Pi counties, Sichuan province; Heqing,Yunnan province) and different qualities (Chuanxiong, Naixiong and Lingzi). Thechemical constituents of essential oil from L. chuanxiong were analyzed by GC-MS and were compared each other. The third chapter is about the chemical constituents of rhizomas of N. forbesii,which belongs to a endemic genus of China. Thirteen compounds were isolated andidentified. One of them is a new dihydroisocoumarin and the structure was identifiedas 6-methoxy-hydrangenol (37) by spectral evidence. The fourth chapter is a review on study progress of chemical constituents ofLigusticum species and Cnidium offcinale.

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花椒(Zanthoxylum piperitum)是川西干旱河谷地区的重要经济作物,化感作用是花椒连作障碍的原因之一。系统研究花椒化感作用有助于深入理解并最终解决花椒连作障碍。本文通过研究花椒叶、林下土壤浸提液及单一纯化感物质对花椒幼苗生长、苜蓿种子萌发及幼苗生长的影响作用,从生理生化角度揭示浸提液及纯化感物质的作用方式。通过室外和室内模拟实验,对浸提液及纯化感物质的化感效应进行比较,为花椒连作障碍的解决和化感作用机制的深入理解提供依据。主要结果如下: 1.花椒叶及林下土壤浸提液对地下生物量影响作用强与对地上生物量的化感效应,两种浸提液的化感效应强度不同,叶浸提液作用表现更显著。其中在Y6、Y8 、T6和T8处理时,花椒幼苗地下生物量分别降低了31.2%、32.1%、31.6%和31.7%。 2.两种浸提液均能显著影响花椒幼苗体内的保护性酶活性,总体说来,在高浓度下抑制各种抗氧化物酶活性,幼苗体内丙二醛含量增加,幼苗受害严重;在较低浓度下,各种保护性酶活性有所增加,丙二醛含量减少,幼苗伤害减轻。同时,不同月份里,各种酶的活性高低显著不同,9月份的活性显著低于7月份的酶活性。对于养分含量的影响,Y8、T8的影响强度最大,分别使碳元素含量降低了27.8%和30.8%,使钾元素含量降低了34.7%和25.6%。 3.花椒叶及林下土壤浸提液对苜蓿种子萌发及幼苗生长有化感作用,表现在最终萌发率、不同物质代谢及保护性酶活性的差异上。两种浸提液对苜蓿种子萌发过程中蛋白质的含量均无显著性影响,对淀粉和可溶性糖的影响作用类似,高浓度处理无明显化感效应,较低浓度处理显著降低二者在萌发苜蓿种子中的含量。Y2、Y4与T4处理分别使可溶性糖含量减少了32.3%、29.1%和18.8%,Y2与T2处理分别使淀粉含量降低了29.3%和26.8%。 4.苜蓿种子在4种单一化感物质最高浓度即10-3 mol•L-1处理下,萌发率显著降低,半数萌发时间推迟,随着处理浓度降低,抑制作用逐渐减弱,当降低到10-6 mol•L-1时,又能够表现出对苜蓿种子萌发的促进作用。 5.纯化感物质在10-6 mol•L-1时使苜蓿幼苗叶片的保护性酶活性显著升高,丙二醛含量显著降低;在10-3 mol•L-1时使苜蓿叶片中保护性酶活性显著降低,丙二醛含量增加,膜脂过氧化程度加重。 Zanthoxylum piperitum is one of the most important cash crops and has been extensively cultivated in Eastern Tibetan Plateau, especially in the fragile dry valley areas. Allelopathic effects could be a reason for Z. piperitum’s continuous cropping impediment. Systemmatically research of the effect of Z. piperitum allelopathy could help to comprehend the continuous cropping impediment. The allelopathic effects on seedlings growth and seed germination of aqueous extracts of Zanthoxylum piperitum and phenolic allelochemicals were studied, and the action mechanism of the two substances was also discussed from physiology. Indoor and outdoor experiments were set to compare the difference between aqueous extracts and pure allelochemicals. The main results showed that: 1. The aqueous extracts of leaf and soil had significant allelopathic effects on aboveground and underground biomass, but the effect on underground biomass was stronger than the effect on underground evidently. Treated with Y6、Y8 、T6 and T8, the underground biomass was reduced 31.2%、32.1%、31.6% and 31.7% respectively. 2. The activity of activities of superoxide dismutase, catalase, peroxidase and ascorbate peroxidase were significantly reduced, while the content of MDA was increased and the seedlings were suffered stronger, when treated by the high concentration; but at the low concentration, these were reversed. And then, at the different month, the activities of antioxidant enzyme were significantly distinct. As for the contents of nutrient element, Y8、T8 had the more intensive effects than other treatments. 3. The results showed that the two types of aqueous extracts had significant allelopathic effects on seed germination, substances metabolize and the activity of antioxidant enzyme. But the aqueous extracts had no effects on the content of protein, while had the similar effects on the content of starch and soluble sugar. At Y2、Y4 and T4, the content of soluble sugar decreased 32.3%、29.1% and 18.8% respectively. 4. Treated with 10-3 mol•L-1 of the four allelochemicals, the seed germination of alfalfa was significantly inhibited. Ferulic acid, coumarin and vanillic acid at 10-3 mol•L-1 significantly reduced the activities of antioxidant enzyme, while the content of MDA in alfalfa seedling was significantly increased. The restrain effects became weakened with the treat concentration falled. However, ferulic acid, coumarin and vanillic acid could increase the activities of antioxidant enzyme at 10-6mol•L-1.