共查询到17条相似文献,搜索用时 78 毫秒
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二球悬铃木冬芽休眠的温度特性 总被引:2,自引:0,他引:2
为了探讨树木冬芽休眠与分布的相互关系以及悬铃木冬芽休眠机理,研究了悬铃木冬芽休眠的温度特性.结果表明:(1)悬铃木冬芽具有浅冬休眠特性,在25℃条件下即使深休眠期的冬芽也能够部分萌发,萌芽率达到40﹪~60﹪,但在15~20℃低温下不能萌发,而随着经历低温量的增加,休眠逐渐得到解除,在春季的10~15℃低温下也能萌发;(2)悬铃木冬芽的休眠解除的低温范围较大,5℃与12℃具有同样的低温效果,15℃也有较大的低温效果,甚至20℃也有低温效果,不同于温带树种,但与横跨亚热带与暖温带分布的山桐子相似;(3)9~10月份为悬铃木的休眠导入期,10月下旬进入深休眠期,同时进入休眠解除期,经过冬季低温信号的诱导,休眠得以解除,保证春季冬芽的正常萌发;(4)悬铃木冬芽能否萌发取决于芽鳞的阻碍作用力与生长点、叶原基或花原基萌发力的平衡状态,当阻碍力大于萌发力表现为冬芽不能萌发,当阻碍力小于萌发力表现为冬芽的萌发;(5)芽鳞除了具有阻碍作用和抵御冬季寒冷干燥气候外,还具有利用冬季低温解除其休眠的作用,在解除其休眠的过程中既提高了生长点、叶原基或花原基的萌发力,也降低了芽鳞的阻碍力;(6)悬铃木冬芽内的主芽和副芽休眠特性不同,在主芽萌芽能力弱时,副芽的萌芽能力增强,反之,主芽萌芽力强时,副芽的萌发就会受到抑制,当主芽能够经过冬季低温解除休眠能够萌发时,冬芽内的副芽重新进入休眠状态,可能是系统维持的一种生态适应;(7)二球悬铃木能横跨亚热带与暖温带广泛栽培正是由悬铃木冬芽休眠的生理生态特性决定的. 相似文献
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二球悬铃木树皮的化学成分 总被引:1,自引:0,他引:1
二球悬铃木树皮的化学成分王静蓉段金廒周荣汉唐敏玲(中国药科大学植化分类及中药资源学研究室,南京210038)ChemicalconstituentsfrombarkofPlatanusacerifoliaWild.WangJingRong,Duan... 相似文献
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对淮南市污染区(矿区)和对照区(相对清洁区)空气中TSP、PM10-100、PM5-10、PM2.5-5和PM2.5的日均质量浓度进行了测定,并对TSP中Cd、Cr、Cu、Ni、Pb和Zn的质量浓度和二球悬铃木〔Platanus×acerifolia(Ait.)Willd.〕叶片中Cd、Cr、Cu、Ni、Pb和Zn含量的动态变化进行了分析,同时对二球悬铃木叶片中重金属含量与TSP中重金属质量浓度和各类空气颗粒物日均质量浓度的相关性进行了分析。结果表明:在60 d采样期内,空气颗粒物日均质量浓度和叶片中重金属含量均呈波动的变化趋势,其中污染区空气中TSP和PM2.5的日均质量浓度均显著高于对照区,污染区PM10-100、PM5-10和PM2.5-5日均质量浓度总体上低于对照区;污染区空气TSP中6种重金属元素的质量浓度均高于对照区,污染区二球悬铃木叶片中的Cd、Cr、Cu、Ni和Zn含量均高于对照区但Pb含量低于对照区。相关性分析结果表明:污染区二球悬铃木叶片中重金属含量与空气TSP中重金属质量浓度多数呈正相关,叶片中重金属含量与空气中PM2.5日均质量浓度也均呈正相关,其中叶片中Cd含量与PM2.5日均质量浓度的相关性达显著水平。研究结果表明:在淮南矿区,可将二球悬铃木叶片中的重金属含量作为空气PM2.5污染状况的监测指标。 相似文献
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二球县铃木[Platanus ×acerifolia (Ait.)Willd.]是县铃木科(Platanaceae)县铃木属(Platanus L.)速生阳性高大乔木,易繁殖、抗性强、树冠广展、叶大荫浓、适应性强、萌蘖和伤口愈合能力强、耐整形修剪、根系发达、抗风力强,被广泛用作行道树和庭荫树,是城市园林绿化的主要树种之一. 相似文献
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以交通繁忙区(污染点)和相对清洁区(对照点)道路两侧的二球悬铃木〔Platanus acerifolia ( Ait.) Willd.〕为研究对象,测定了不同器官(包括主干、老树皮、2年生枝条、1年生枝条、腋芽、叶片和果实)中Cu、Ni、Pb和Zn的含量,并对污染点二球悬铃木各器官中4种重金属元素的累积量和污染指数及二者的分布比例进行分析。结果表明:二球悬铃木体内重金属元素的含量因样点、器官及元素的不同而呈现不同的变化规律,污染点4种重金属元素的累积量及其分布比例、污染指数及其分布比例则因器官和元素的不同而有明显差异。总体上看,污染点各器官的Cu、Ni、Pb和Zn的含量均高于对照点且差异显著(P<0.05);4种重金属元素相比较,均以Zn含量最高,Cu含量次之,而Ni和Pb含量则较低;在不同器官中同一重金属元素的含量也有明显差异,其中,Cu、Ni和Zn含量均在腋芽中最高,Pb含量在2年生枝条中最高。4种重金属元素的累积量及其分布比例均在叶片中最高,在老树皮中次之,在1年生枝条、2年生枝条和腋芽中均较低;而4种重金属元素的污染指数及其分布比例则在老树皮中最高,在叶片中次之。研究结果显示:二球悬铃木各器官对空气中的重金属元素均有一定的吸滞能力,并且叶片和老树皮的吸滞能力明显优于其他器官。 相似文献
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环境胁迫下的植物细胞程序性死亡及其意义 总被引:5,自引:0,他引:5
从低氧适应、抗病反应、抗盐机制等方面阐明了环境胁迫下的植物细胞程序性死亡(PCD)的普遍性,并就PCD在植物抵御不良环境中的意义进行讨论。 相似文献
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The developmental stability indices,leaf width based fluctuating asymmetry (FA1),and lateral vein length based directional asymmetry (RDA1) of Platanus acerifolia were studied.All the leaves were sampled from 14 sites that were categorized based on different urban environmental stress levels (UESL) in Shanghai metropolitan,China.Besides,foliar stomatal density and stomatal length were also studied as the subsidiary indices to test the availability of developmental stability indices as the indicator under a stressful environment.Results showed seasonal variation of FA1 and RDA1 existed among the 14 sites,but the data showed significant negative correlation between FA1 and UESL (FA1=0.029-0.000 9UESL+0.000 3UESL2,r=0.766 5,P=0.001 4).However,a similar trend was not found between RDA1 and UESL.Furthermore,the significant correlation among FA1 and leaf stomatal length and stomatal density implied they could be used as indicators of urban stress levels on a small scale.It seemed that RDA1 was possibly a normal parameter during leaf development but it was unavailable for use as an indicator of urban stresses. 相似文献
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The developmental stability indices, leaf width based fluctuating asymmetry (FA1), and lateral vein length based directional
asymmetry (RDA1) of Platanus acerifolia were studied. All the leaves were sampled from 14 sites that were categorized based on different urban environmental stress
levels (UESL) in Shanghai metropolitan, China. Besides, foliar stomatal density and stomatal length were also studied as the
subsidiary indices to test the availability of developmental stability indices as the indicator under a stressful environment.
Results showed seasonal variation of FA1 and RDA1 existed among the 14 sites, but the data showed significant negative correlation
between FA1 and UESL (FA1 = 0.029 − 0.000 9UESL + 0.000 3UESL2, r = 0.766 5, P = 0.001 4). However, a similar trend was not found between RDA1 and UESL. Furthermore, the significant correlation among
FA1 and leaf stomatal length and stomatal density implied they could be used as indicators of urban stress levels on a small
scale. It seemed that RDA1 was possibly a normal parameter during leaf development but it was unavailable for use as an indicator
of urban stresses.
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Translated from Chinese Journal of Ecology, 2005, 24(7): 719–723 [译自: 生态学杂志, 2005, 24(7): 719–723] 相似文献
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梧桐花粉致敏大鼠动物模型的建立及特异性抗体检测 总被引:1,自引:0,他引:1
用梧桐花粉浸液作为过敏原,经皮下多点注射对实验动物进行免疫,用雾化的梧桐花粉浸液进行激发,建立了变态反应性疾病的实验动物模型。随后通过ELISA、Western印迹等方法对其血清中的梧桐抗原特异性IgG、IgE进行检测。结果显示有特异性IgG、IgE抗体的存在。 相似文献
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Asymmetry in bilateral traits is often used to assess an individual'squality and stress resistance, but stress-induced variationin developmental stability is largely undocumented for free-livingpopulations. Over many years, grizzly bears (Ursus arctos horribilis)extensively foraged around garbage dumps in Yellowstone NationalPark. Abrupt closure of these dumps 26 years ago was a severelystressful event and was followed by excessive mortality anda many-fold increase in grizzly home-range size. I examine howthis stress affected developmental stability by comparing dentitionof bears born before and after the dump closure. I predictedthat (1) asymmetry in dentition should be greater in bears bornafter dump closure compared to before closure, and asymmetryin sexually selected canines should change more than nonsexuallyselected premolars following dump closure and (2) the relationshipbetween tooth asymmetry and tooth size should change in thepopulations following the stressful events as compared withpopulations before stressful events. I found that developmentalstability of canines, which are under directional sexual selectionin males, was more responsive to stress compared to that ofmale premolars or female dentition (both under stabilizing selection),and, because of the increased cost of canine production, feweranimals were able to achieve both large size and symmetricaldevelopment of these teeth, and thus the slope of the relationshipbetween fluctuating asymmetry and canine size increased. I concludethat stress appears to act as an honesty-reinforcement mechanismin sexual selection for symmetrical dentition. 相似文献
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Fluctuating asymmetry does not reflect environmental stress during incubation in an oviparous lizard
Christopher G. Longson Kelly M. Hare Charles H. Daugherty 《New Zealand journal of zoology.》2013,40(2):91-96
Abstract We analysed the relationship between incubation regime and fluctuating asymmetry in a cohort of juvenile lizards (Oligosoma suteri) incubated under laboratory conditions. We found no relationship between incubation temperature or water potential and the level of asymmetry in two cranial traits, although previous research showed profound effects of incubation temperature on gross morphology and hatching success. Our results suggest that fluctuating asymmetry is not a reliable indicator of developmental stress in this species. 相似文献
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城市环境保护规划与生态建设指标体系实证 总被引:42,自引:4,他引:42
在回顾分析各类环境指标体系的基础上,将环境指标体系分为3类:(1)综合性的可持续发展指标体系;(2)区域一半规划与管理指标体系;(3)面向某一领域或专题研究的指标体系。结合案例研究提出了一种面向规划与管理的城市环境保护与生态建设指标体系。该体系综合考虑环境保护与污染控制、生态保护与建设、生态环境管理以及经济发展、城市与社会发展5个专题要素,前3个专题要素组成主体指标系统,后2个组成扩展指标系统。根据规划管理不同层次的需要,设置了核心指标和辅助指标两个复杂程度不同的指标集,分别对应宏观与中观层次的规划要求,并使用灰色关联法对指标体系进行评价。在实例研究中,通过专家咨询法,选择了39项核心指标,31项辅助指标组成上海浦东新区环境保护规划与生态建设指标体系,在计算各项指标现状的基础上,确立了各指标2005年、2010年和2020年的规划值,结合多级灰色关联法,提出了CIEE指数(Comprehensive Index for Environmental Protection and Ecological Construction)对各项指标的现状和变化趋势进行了评价。 相似文献