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1.
四种灌木状与四种乔木状棕榈植物热值的月变化   总被引:15,自引:3,他引:12  
对 4种灌木状棕榈植物 (香棕、袖珍椰子、棕竹、江边刺葵 )与 4种乔木状棕榈植物 (假槟榔、董棕、国王椰子、大王椰子 )叶的热值和灰分含量的月变化进行了研究。结果表明 :( 1 ) 8种植物叶的灰分含量存在差异且具有不同的月变化 ;从灰分含量的比较看 ,乔木类的 4种植物叶平均灰分含量分别为 :假槟榔 1 3.64%± 2 .94%、董棕 9.74%± 1 .90 %、国王椰子 9.1 2 %± 1 .1 8%、大王椰子 8.69%± 3.5 5 % ;灌木类的 4种植物叶平均灰分含量分别为 :棕竹 8.73%± 2 .5 2 %、袖珍椰子 8.67%± 1 .1 9%、香棕 8.63%± 1 .2 0 %、江边刺葵 7.60 %± 0 .98% ,乔木类植物 (除大王椰子外 )叶平均灰分含量高于灌木类的植物 ;( 2 )从干重热值的月变化来看 ,分 3种类型 :江边刺葵与棕竹有相反的变化趋势 ;假槟榔、董棕、袖珍椰子的月变化趋势相同 ;国王椰子、香棕、大王椰子具有各自的变化趋势 ;在 8种棕榈植物中 ,除香棕外 ,灌木类的植物平均干重热值大于乔木类 ;灌木类中 ,茎单生的江边刺葵干重热值高于茎丛生的棕竹、香棕和袖珍椰子 ;( 3)假槟榔、袖珍椰子、大王椰子的干重热值与灰分含量具有极显著的线性相关 ( P<0 .0 1 ) ,棕竹的干重热值与灰分含量有显著的线性相关 ( P<0 .0 5 ) ;而香棕、董棕、江边刺葵、国王椰  相似文献   

2.
福建东山短枝木麻黄小枝氮磷含量及其再吸收率季节动态   总被引:3,自引:0,他引:3  
叶功富  张立华  林益明  王亨  周海超  曾琦 《生态学报》2009,29(12):6519-6526
对福建东山赤山林场短枝木麻黄纯林小枝中的N和P含量、N ∶ P比、养分再吸收率的季节动态进行研究.结果表明,随着小枝的成熟和衰老,各季节N和P的含量依次降低,其中衰老小枝中N和P含量分别为(3.97±0.21)~(8.64±0.58) mg · g~(-1)和(0.04±0.03)~(0.10±0.03) mg · g~(-1),基本上表现为N和P的完全再吸收.成熟小枝N ∶ P比的季节动态介于(18.67±3.24)~(37.98±1.32)之间,均高于16,表明木麻黄的生长受到不同程度的P限制.N、P再吸收率的季节变化分别为(51.02±4.66)%~(63.00±8.61)%和(81.24 ±5.08)%~(91.78±5.84)%,P再吸收率显著高于N.N和P的再吸收率之间以及成熟叶中N、P含量与二者再吸收率之间没有显著相关性,但在衰老叶中存在显著负相关,表明养分再吸收程度越高,其再吸收率就越高.因此,木麻黄通过小枝衰老过程中的养分再吸收,减少养分的损失,从而适应贫瘠的立地条件.  相似文献   

3.
几种红树植物木材热值和灰分含量的研究   总被引:46,自引:6,他引:40  
在夏季对海南东寨港红树林自然保护区一些红树植物木材的灰分含量和热值进行了测定,并研究了夏季不同纬度的秋茄 (Kandelia candel)木材热值的变化.结果表明,红树植物木材的灰分含量较低,在2.43%~5.17%之间;干重热值在17.23~19.21kJ·g-1之间,去灰分热值在 17.70~20.10kJ·g-1之间;嗜热窄布种无瓣海桑 (Sonneratia apetala)木材的干重热值和去灰分热值均是最低;在夏季秋茄木材的热值随纬度升高而下降.  相似文献   

4.
几种红树植物的热值和灰分含量研究   总被引:15,自引:0,他引:15       下载免费PDF全文
本文主要研究我国东南沿海红树植物叶的灰分含量和热值含量的变化。在海南琼山沿海不同种红树植物之间,随叶灰分含量增加(7.11—9.8%)而干重热值减少(20.62—18.87kJ/g),但去灰分热值变化不大,在21.5kJ/g左右。同一种秋茄植物,在纬度较低(低于24˚N)的地区,叶灰分含量较低,干重热值较高;在纬度较高时(高于24˚N)则相反。秋茄幼树(1—7龄间)随年龄增长灰分含量下降,干重热值提高,而去灰分热值变化不大。热值季节变化中,夏秋较高,冬春较低。  相似文献   

5.
在冬季对福建省华安县竹园14属46种(含变种和栽培型)竹类植物叶的热值和灰分含量进行了研究。结果表明:竹类植物叶的灰分含量在8.05%~28.14%之间,平均为15.18%;干重热值在14957.3 ~19111.4 J/g之间,平均为17672.1 J/g;去灰分热值在19473.1~24646.2 J/g之间,平均为20845.6 J/g;竹类植物叶干重热值和灰分含量有显著的线性关系,相关方程为Y=-169.21X+20241(r=0.7370**,df=44),高灰分含量是竹叶干重热值相对较低的重要原因之一。  相似文献   

6.
对布迪椰子的幼叶、成熟叶、叶柄和根在不同季节的干重热值、去灰分热值和灰分含量进行了研究,结果表明:干重热值四个季节的平均值为成熟叶(20.65kJg-1)>幼叶(19.84kJg-1)>根(19.55kJg-1)>叶柄(18.77kJg-1),秋季的干重热值明显高于其它三个季节的干重热值,冬季的干重热值最低,去灰分热值与干重热值的变化趋势基本相同。灰分含量四个季节的平均值为根(5.14%)>叶柄(4.33%)>幼叶(4.21%)>成熟叶(3.97%)。成熟叶的灰分含量一直维持在比较低的水平,而幼叶的在秋季明显下降,在冬季明显上升,幼叶灰分含量的季节变化趋势与成熟叶的相同,叶柄灰分含量在冬季明显低于根部。布迪椰子这种不同器官在不同季节的热值和灰分的变化规律显示其具有较强的耐寒适应性。  相似文献   

7.
浙江北山七子花群落主要植物叶热值   总被引:10,自引:0,他引:10  
郝朝运  刘鹏 《生态学报》2006,26(6):1709-1717
对不同季节浙江北山七子花群落18种优势植物叶的热值和灰分含量进行了研究,探讨了生境片断化所造成的影响。结果表明:(1)不同种类植物叶的灰分含量有较大差异,与植物自身的遗传特性有关(主要是叶的元素含量),其中仅乔木层算盘子(Glochidion puberum)和灌木层华箬竹(Sasamorpha sinica)的灰分含量高于10%,其他植物灰分含量较低;不同季节植物的灰分含量不同,且具有不同的季节变化趋势;从群落林冠到地被层,各层植物叶的平均灰分含量由高到低依次为乔木层(7.49%±2.59%)、灌木层(7.20%±3.22%)、草本层(6.68%±1.02%)和间层(6.28%±1.31%),但层次间差异不显著(p>0.05)。(2)不同种类植物叶的去灰分热值变化范围较大,有6种植物的去灰分热值高于20.00 kJ/g,4种植物低于18.00 kJ/g,同一层次内常绿植物叶的去灰分热值一般比落叶植物高;从林冠到地被层,各层植物叶的去灰分热值由高到低依次为灌木层((20.33±2.29)kJ/g)、乔木层((19.92±1.05)kJ/g)、间层((19.71±3.26)kJ/g)和草本层((18.14±0.74)kJ/g),仅乔木层和草本层之间的差异达到显著水平(p<0.05);不同季节植物叶的去灰分热值变化较为复杂,其中多数植物在春秋季热值含量较高,夏季热值含量较低。(3)对不同生境条件下3种乔木植物叶的热值和灰分含量的比较研究显示,由于受到片断化后光照增强等因素的影响,与林内相比林外生境植株叶的干重热值和去灰分热值均明显升高(p<0.05),而灰分含量变化规律不明显。分析认为,生长速率慢和某些高热值成分的积累是造成片断化条件下植物叶热值升高的主要原因。  相似文献   

8.
草地植物作为生物燃料供给料已经被人们所提及,而植物的热值和灰分含量作为评价生物燃料质量的重要指标,却很少被人们研究。本文通过对内蒙古锡林河流域羊草草原5种多年生禾本科植物(羊草、冰草、大针茅、羽茅和隐子草)的热值和灰分进行测定,探讨了植物热值和灰分的月变化及二者之间相关性。结果表明:5种植物干重热值及去灰分热值月变化均为单峰形变化曲线,干重热值的最大值出现在8月(19.2MJ·kg-1),去灰分热值最大值出现的月份因植物种类不同而表现一定的差异;灰分含量的月变化趋势表现为先降低后升高;冰草、大针茅和隐子草干重热值与灰分含量之间表现为极显著线性负相关(P<0.01),羽茅干重热值与灰分之间表现为显著线性负相关(P<0.05),而羊草干重热值与灰分含量之间的相关性不显著。  相似文献   

9.
五种丛生状棕榈植物叶热值的月变化研究   总被引:11,自引:2,他引:9  
对5种丛生状棕榈植物一欧洲棕、细叶棕竹、小箬棕、玲珑椰子、缨络椰子的叶片热值和灰分含量的月变化进行了研究,结果表明,5种植物具有较高的灰分含量,但灰分含量的月变化趋势各不相同;欧洲棕、细叶棕竹、小箬棕3种植物干重热值的月变化趋势有些差异,同属的缨络椰子、玲珑椰子干重热值的月变化趋势基本相似;缨络椰子、小箬棕的干重热值与灰分含量具有显著的线性相关(P<0.05),而其余3种植物的干重热值与灰分含量相关性不显著(P>0.05);从去灰分热值的月变化来看,细叶棕竹与小箬棕,缨络椰子与玲珑椰子的月变化趋势相似。  相似文献   

10.
福建华安竹园一些竹类植物叶的热值研究   总被引:33,自引:0,他引:33  
在冬季对福建省华安县竹园14属46种(含变种和栽培型)竹类植物叶的热值和灰分含量进行了研究。结果表明:竹类植物叶的灰分含量在8.05%-28.14%之间,平均为15.18%;干重热值在14957.3-19111.4J/g之间,平均为17672.1J/g;去灰分热值在19473.1-24646.2J/g之间,平均为20845.6J/g;竹类植物叶干重热值和灰分含量有显著的线性关系,相关方程为Y=-169.21X 20241(r=0.7370,df=44),高灰分含量是竹叶干重热值相对较低的重要原因之一。  相似文献   

11.
通过对6种藓类植物,即褶叶青藓(Brachythecium salebrosum(Web.et Mohr.)B.S.G.)、湿地匐灯藓(Plagiomnium acutum(Lindb.)Kop.)、侧枝匐灯藓(Plagiomnium maximoviczii(Lindb.)Kop.)、大凤尾藓(Fissidensnobilis Griff.)、大羽藓(Thuidium cymbifolium(Doz.et Molk.)B.S.G.)和大灰藓(Hypnum plumaeforme Wils.)嫩茎和老茎的石蜡切片和显微观察发现,同一藓类植株的嫩茎和老茎,茎结构稳定,不同种藓类植物茎横切面具有不同特征.植物体茎横切面形状、表层细胞的层数、细胞大小和细胞壁厚薄、皮层细胞大小和形状、中轴的有无以及比例等特征可以作为藓类植物的分科分类依据之一.  相似文献   

12.
Seed germination of an aurea mutant of tomato ( Lycopersicon esculentum Mill.) is promoted by continuous irradiation with red, far-red or long-wavelength far-red (758 nm) light as well as by cyclic irradiations (5 min red or 5 min far-red/25 min darkness). Far-red light applied immediately after each red does not change the germination behaviour. Seed germination of the isogenic wild-type, cv. UC-105, is promoted by continuous and cyclic red light while it is inhibited by continuous and cyclic far-red light and by continious 758 nm irradiation. Far-red irradiation reverses almost completely the promoting effect of red light. The promoting effect (in the aurea mutant) and the inhibitory effect (in the wild-type) of continuous far-red light do not show photon fluence rate dependency above 20 nmol m−2 s−1. It is concluded that phytochrome controls tomato seed germination throgh low energy responses in both the wild type and the au mutant. The promoting effect of continuous and cyclic far-red light in the au mutant can be attributed to a greater sensitivity to Pfr.  相似文献   

13.
14.
真菌类遗传学分析的知识结构教学   总被引:5,自引:2,他引:3  
罗桂花 《遗传》2002,24(3):349-350
本文以认知结构理论为指导,讨论了真菌类遗传分析与高等动植物遗传分析的内在联系,认为利用这种内在联系进行教学可收到好的效果并说明了作者的具体教学过程。 Abstract:In the paper, the relationship between genetic analysis of Fungi and genetic analysis of high animal and plant was discussed.A good results were obtained when we adopted this method in the teaching.  相似文献   

15.
The levels of endogenous phytohormones and respiratory rate in nine sorts of flowers such as Cymbidium faberi Rolfe, Nopalxochia ackermannii Kunth and others were investigated both at full bloom and senescence and meanwhile the effect of exogenous phytohormones on prolonging the blossoms and promoting ethylene production were tested. There is a high content of endogenous ethylene in all the long-lived flowere, about 3–16 folds higer than the short-lived ones. There is a high level of ABA at full blooming flowers of short-lived flowers, in which there is no or only some cytokinins in it, but the ratio of CTK (6BA+zeatin)/ABA is smaller(l.7). The endogenous ABA reached a much higher level at senescence in all nine sorts of flowers, so it is reasonable to consider that it is ABA which plays an important role of regulation in controlling flower's senescence. There is a much higher level of GA3 and zeatin in the long-lived flowers which is not demonstrated in the shortlived ones. The respiratory rate is one of the factors controtling the longevity of flowers, but it does not play a decided role. Application of 6BA and zeatin prolongs distinctly orchid’s longevity, however exogenous IAA through the promotive action on ethylene production, evidently extends the longevity of the flowers of the Nopalxochia ackermannii Kunth.  相似文献   

16.
A complex analysis of seasonal fluctuations of the mean group parameters of the system of regulation of lipid peroxidation has been performed in liver of Balb/c mice. Association of lipid characteristics and morphophysiological parameters is studied in the Balb/c mouse liver. An inter-connection is revealed between the liver index and the amount of lysoforms of phospholipids, the scale and character of the interconnection differing essentially depending on proportion of phos-phatidylcholine in mouse liver phospholipids.  相似文献   

17.
龙胆科药用植物化学成分的研究现状   总被引:16,自引:0,他引:16  
龙胆科植物在我国的分布范围很广,且多数为药用植物,其多数种属的药用植物,至今其化学成分尚未被系统研究。综述了目前龙胆科药用植物的化学成分的研究现状及一般提取方法,对近年来发现的环烯醚萜及裂环烯醚萜类化合物进行了总结,为本科药用植物的更深入研究提供了参考。  相似文献   

18.
19.
Seven strains of aerobic carbon monoxide-oxidizing bacteria (carboxydebacteria) when growing on CO as sole source of carbon and energy had doubling times which ranged from 12–42 h. The activity profiles obtained after discontinuous sucrose density gradient centrifugation indicated that the CO-oxidizing enzymes are soluble and the hydrogenases are membrane-bound in all strains examined. The CO-oxidizing enzymes of Pseudomonas carboxydohydrogena, Pseudomonas carboxydoflava, Comamonas compransoris, and the so far unidentified strains OM2, OM3, and OM4 had a molecular weight of 230,000; that of Achromobacter carboxydus amounted to 170,000. The molecular weights of the CO-oxidizing and H2-oxidizing enzymes turned out to be identical. The cell sonicates were shown to catalyze the oxidation of both CO and H2 with methylene blue, thionine, phenazine methosulfate, toluylene blue, dichlorophenolindophenol, cytochrome c or ferricyanide as electron acceptors. Methyl viologen, benzyl viologen, FAD+, FMN+, and NAD(P)+ were not reduced. The spectrum of electron acceptors was identical for all strains tested. Neither free formate, hydrogen nor oxygen gas were involved in the CO-oxidation reaction. Methylene blue was reduced by CO at a 1:1 molar ratio. The results indicate that CO-oxidation by carboxydobacteria is catalyzed by identical or similar enzymes and that the reaction obeys the equation CO+H2OCO2+2H++2e- as previously shown for Pseudomonas carboxydovorans.Dedicated to Otto Kandler remembering almost three decades of enjoyable cooperation  相似文献   

20.
Since the introduction of the concepts of allostery about four decades ago, much advancement has been made in elucidating the structure-function correlation in allostery. However, there are still a number of issues that remain unresolved. In this review we used mammalian pyruvate kinase (PK) as a model system to understand the role of protein dynamics in modulating cooperativity. PK has a triosephosphate isomerase (TIM)(α/β)8 barrel structural motif. PK is an ideal system to address basic questions regarding regulatory mechanisms about this common (α/β)8 structural motif. The simplest model accounting for all of the solution thermodynamic and kinetic data on ligand-enzyme interactions involves two conformational states, inactive ET and active ER. These conformational states are represented by domain movements. Further studies provide the first evidence for a differential effect of ligand binding on the dynamics of the structural elements, not major secondary structural changes. These data are consistent with our model that allosteric regulation of PK is the consequence of perturbation of the distribution of an ensemble of states in which the inactive ET and active ER represent the two extreme end states. Sequence differences and ligands can modulate the distribution of states leading to alterations of functions. The future work includes: defining the network of functionally connected residues; elucidating the chemical principles governing the sequence differences which affect functions; and probing the nature of mutations on the stability of the secondary structural elements, which in turn modulate allostery.  相似文献   

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