龙苍沟国家森林公园7种花楸属植物的叶解剖特征及其环境适应性

采用石蜡切片法对四川省龙苍沟国家森林公园内7种花楸属（Sorbus）植物的叶解剖特征进行研究,探究其结构特征与生境的相关性。结果显示：7种植物的叶片均为典型的背腹叶;叶片厚度介于108.16~208.21 μm,种间差异极显著（P<0.01）;上表皮厚度均大于下表皮厚度,且复叶物种的下表皮细胞均有乳突;栅栏组织由1~2层细胞构成,仅多对西康花楸（S. prattii var. aestivalis）的栅海比（栅栏组织与海绵组织的厚度比）为1.93,其余6种植物的栅海比均小于1;中脉维管束均呈心型,为典型的外韧型维管束,种间中脉突起度存在极显著差异（P<0.01）。各解剖结构中,上、下表皮可塑性最大,在生境中具有较强的潜在适应能力;中脉可塑性最小,整体结构较为稳定。栅栏组织、海绵组织和中脉组织是7种植物中种间差异最大的解剖结构。叶解剖结构与生境因子的相关性分析表明,栅栏组织厚度、栅海比和紧密度与年降水量、最暖季降水和海拔正相关（P<0.05）,与季节性温差负相关（P<0.05）;中脉直径和突起度与季节性温差呈正相关（P<0.01）,与年降水量、最暖季降水和海拔正相关负相关（P<0.05）。叶解剖结构性状的适应性变化,体现了7种花楸属植物在龙苍沟国家森林公园的生存策略。     

12种短命植物叶解剖结构及其对荒漠环境的适应性

以分布于新疆北部古尔班通古特沙漠南缘的12种短命植物为研究材料,采用常规石蜡切片法,对其叶的解剖结构进行了观察分析,探讨12种短命植物的叶解剖结构对荒漠生态环境的适应性关系。结果显示:(1)12种短命植物中,有8种植物的叶肉栅栏组织发达,表现出等面叶特征;有7种植物侧脉维管束具有花环状结构,表现出C4植物特点。(2)12种植物叶片均具有气孔下室,其中,小花荆芥等7种植物叶片具有发达的气孔下室。(3)12种植物叶肉及叶脉中常有晶体存在,晶体数量及大小在不同植物中有差异。研究认为,12种短命植物从总体上呈现出旱生结构特征,从个体角度看这些特征是不同类群的植物以不同方式适应沙漠干旱环境的结果,但不足以改变该类植物的中生性质。     

青藏高原草地植物叶解剖特征

运用常规石蜡制片技术对我国青藏高原66种草地植物优势种的叶解剖特征进行研究,并分析了叶解剖特征与海拔、生长季降水及生长季均温之间的关系.结果表明:青藏高原草地植物叶片具有很多适应高寒环境的结构特征,如表皮层厚且表皮细胞大小差异显著,表皮毛等表皮附属物发达,异细胞丰富,通气组织普遍发达等;叶片各组成部分厚度的变异程度不同,其中海绵组织厚度变异最大,其次为上角质层、下表皮层、下角质层、上表皮层、栅栏组织,叶片厚度的变异最小;青藏高原草地植物叶片各组成部分的厚度存在协同进化,上下角质层厚度呈强烈正相关,海绵组织厚度与叶片厚度相关性最强;青藏高原草地植物叶片各组成部分的厚度与海拔、生长季降水、生长季均温3个重要环境变量呈较弱的相关性,总体表现为随海拔升高叶片各组成部分的厚度减小,而随生长季降水和生长季均温的增加叶片厚度增加.     

青藏高原雪白委陵菜(Potentilla nivea)叶片性状对海拔的响应

利用生态学常规方法、石蜡切片和显微观察技术,对青藏高原东北部的冷龙岭不同海拔(3600～4200 m)原位生长及移栽的雪白委陵菜(Potentilla nivea)叶片外部形态和解剖结构进行观察,探究其叶片性状对海拔的响应以及生态适应性。结果表明：随海拔的升高,气温呈明显的降低趋势(约为0.66℃·100 m^-1),而辐射和降水并未出现显著性差异;对于不同海拔原位生长的雪白委陵菜,总体上其叶片外部形态和解剖结构指标均存在显著差异(P<0.05),株高、叶片大小及比叶面积均随海拔升高呈减小趋势,而叶干物质含量、比叶重、叶片厚度、栅栏组织厚度、海绵组织厚度、栅栏系数和叶片紧密度则随海拔升高而增加。然而,从3800、4000和4200 m移栽到3600 m的雪白委陵菜,其叶宽、比叶面积、比叶重、叶干物质含量、角质层厚度、表皮厚度、海绵组织厚度和叶片紧密度均无显著差异。研究发现,无论是不同海拔原位生长还是移栽的雪白委陵菜,其叶片外部形态和内部解剖结构均表现出对海拔变化的敏感性,植物通过来改变自身性状以适应环境,且叶片性状之间存在协同变化。     

风毛菊属3种植物叶的解剖结构比较

采用石蜡切片法对分布于祁连山海拔5 000 m左右流石滩上菊科风毛菊属水母雪兔子（Saussurea medusa Maxim）、鼠曲雪兔子（Saussurea gnaphalodes (Royle) Sch.）、红叶雪兔子（Saussurea paxiana Diels.）3种植物叶片的解剖结构进行了比较研究,结果表明：叶片表皮细胞均为单层,上下表皮都有气孔分布,气孔不下陷;角质层较厚,叶表面均被单列细胞的表皮毛。3种植物均为异面叶;叶肉栅栏组织较发达,通常由2～3层细胞组成,但栅栏组织细胞排列较疏松;海绵组织存在大量的细胞间隙;叶肉中通气组织发达,且均有不规则裂生性气腔。叶脉维管束中韧皮部都具有异细胞存在。这些共同特征是3种植物对高山地区缺氧、低温、强辐射等自然条件长期适应的结果。但是,3种植物在叶片的外部形态特征、叶肉栅栏组织细胞的特点、维管束发育程度、内分泌结构、不规则裂生气腔等方面又存在明显的不同,表现出3种植物对环境的适应也是存在差异的。     

叶片组织结构特征对氯气、二氧化硫的抗性研究

为研究叶片组织结构和植物对大气污染的抗性关系,本文对75种植物叶片的解剖结构进行了观察,并测量了它们的形态指标。初步结论如下:(1)早生结构的叶片,表现为叶较厚、角质层厚等,对大气污染具较强的抗性;(2)具发达贮水组织的肉质叶,抗性较强;(3)阴生结构叶片,如叶较薄、纸质或柔软者,多是敏感植物;(4)在少数科中,如桑科、赤铁科,夹竹桃科等有不少种类属抗性植物;(5)在污染条件下,气孔开放度对植物的伤害有重要影响;(6)栅栏组织细胞层数,栅栏组织厚度和叶片厚度之比,对植物的敏感性没有直接相关关系;(7)叶片解剖结构特征,在评价植物对大气污染的抗性有其局限性。     

星状雪兔子植物叶的解剖结构对高山环境的适应性

对青藏高原东缘两个不同居群的星状雪兔子植物叶的结构进行了显微观察,观察结果表明:两种不同居群植物的叶片类型均为等面叶,表皮细胞单层,角质层厚,表皮细胞形状为多边形,垂周壁平直或弓形。生于海拔2850m处的星状雪兔子植物,叶片厚度为330.66μm,上表皮气孔密度为106.75,下表皮气孔密度为144.79;海拔2890m处的星状雪兔子植物,叶片厚度为537.07μm,上表皮气孔密度为53.6,下表皮气孔密度为77.30。两种植物叶片类型虽然均为等面叶,但明显表现为两种不同的生态类型,这表明了星状雪兔子植物的叶在无表皮毛保护的情况下对高山环境的适应性并不是单一的。     

暗罗属植物叶的比较解剖学研究

利用扫描电镜技术、叶片叶片离析方法和石蜡切片法对暗罗属12种植物叶和形态结构进行了比较研究。结果表明,叶表皮细胞形状、气孔器形态、表皮毛类型、表皮细胞中晶体类型、叶肉中油细胞分布位置、栅栏组织和海绵组织厚度的比值,以及主脉维管组织的结构特征等具有明显的种间差异。可以利用这些叶的解剖特征将暗罗属植物相互区别开来。     

青藏高原2种柳属植物叶片解剖结构和光合特征的比较

对青藏高原不同海拔生境条件下2种柳属植物墨竹柳(Salix maizhokunggarensis)和左旋柳(Salix paraplesia var.subintegra)叶片结构和光合特征进行了比较研究,以探讨植物对高原环境变化的适应性.结果表明:随着海拔的升高,2种柳的叶片解剖结构和光合特征呈规律性变化,主要表现为除气孔面积趋于变小外,叶片的厚度、栅栏细胞的层数、上下表皮的角质层厚度、第一层栅栏组织细胞密度、气孔密度及叶片主脉厚度等指标均呈增加趋势;但海拔的变化对2种柳树叶片结构中的叶片类型、表皮细胞的形状和排列、栅栏细胞的形状、栅栏组织的发达程度、胞间隙以及主脉维管组织的发达程度的影响不明显;随海拔升高,2种柳树的Pn、Gs和Ci值均显著降低,而Ls值显著升高.通过叶片结构和光合数据分析,研究认为2种柳树叶片适应高原环境变化的策略相似,且均以结构变化和牺牲碳同化能力为代价来适应高原环境.     

高山植物全缘叶绿绒蒿叶片形态及解剖结构对海拔的响应

为了阐明高山植物全缘叶绿绒蒿(Meconopsis integrifolia)对海拔及高山环境的形态学适应特征,沿海拔梯度选择了5个海拔的全缘叶绿绒蒿分布区域(3681、3841、4081、4215和4452 m),采用常规石蜡制片技术和显微观察方法,对其形态及叶片解剖结构进行了研究。结果表明:随着海拔的升高,株型方面,全缘叶绿绒蒿的株高、基径逐渐减小;叶片形态方面,叶片逐渐变小,叶形逐渐狭长,具体表现为叶片长度、宽度逐渐减小,叶片长宽比逐渐增大;叶片解剖结构方面,叶片厚度、表皮细胞厚度、海绵组织厚度、组织疏松度及中脉直径呈减小趋势;栅栏组织厚度、栅海厚度比、组织紧密度呈增大趋势;叶表皮结构方面,叶片表皮毛密度、气孔密度及气孔指数均呈增大趋势。此外,解剖结构指标之间大多呈现出明显的协同进化,各形态指标对海拔的变化表现出较大的可塑性。全缘叶绿绒蒿形态及叶片解剖结构在不同海拔上表现出的这种差异,可能是植物长期适应高山复杂环境的结果。     

发育阶段和海拔对岷江源区陇蜀杜鹃小枝功能性状及生物量分配的影响

本研究分析了岷江源区卡卡山典型高山灌丛植物陇蜀杜鹃不同发育阶段(花芽期和开花期)及不同海拔(3600 m低海拔和3800 m高海拔)下功能小枝和叶片性状的差异,以及空间异质性对花芽期和开花期小枝功能性状相关性及其权衡作用的影响。结果表明: 低海拔同一生长期陇蜀杜鹃小枝长度显著大于高海拔,高海拔开花期小枝的花数量和花质量显著高于低海拔。同一海拔花芽期的小枝质量、叶片数量、总叶质量、总叶面积和总叶柄质量均显著大于开花期,单叶质量和单叶柄质量均显著小于开花期。与花芽期相比,开花期叶生物量占比减少了13%,而小枝质量占比显著增加。小枝的生物量权衡表明,花芽期性状倾向于小枝质量,开花期倾向于总叶质量;花芽期的叶偏好分配于单叶质量,低海拔和高海拔开花期叶片分别偏好分配到单叶柄质量和单叶质量。低海拔开花期小枝质量与总叶面积、总叶质量均为异速生长,单叶柄质量和单叶面积为异速生长。海拔和发育阶段共同影响了陇蜀杜鹃功能小枝和叶片的性状。     

High altitude acclimatization in fourArtemisia species: Changes in soluble sugars,starch and lignin contents in the leaves

During high altitude acclimatization soluble sugar contents were highest in temperateArtemisia species when grown at 550 m and tropicalArtemisia species at 3600 m in the active growth phase. During the senescence in all the species the soluble sugar contents were low in plants grown at 3600 m. The starch content was low in the leaves of the tropical and sub-temperate species when grown in the alpine zone but in the temperate species a significantly higher amount of starch was observed at 3600 m altitude. The amount of lignin acids was lower in the tropical and sub-temperate species but higher in the temperate species when these were grown at a higher altitude.     

Effects of sclerophylly and host choice on gall densities and herbivory distribution in an Australian subtropical forest

We hypothesize that upper canopies contrast with the understorey vegetation in gall density and survival because of greater mortality in the latter. We expect that high sclerophylly rates in the upper canopy leaves are a main cause of such pattern, and more important than other environmental traits, for instance related to altitude. The study was conducted in Lamington National Park, Queensland, Australia. Four independent vertical cylindrical transects through the forest canopy and one equivalent, horizontal understorey transect (20 m long and 1 m in diameter) were sampled at different altitude (300, 700, 900 and 1100 m above sea level) during two seasons. Total and damaged leaves were counted, and galls were collected and opened to determine if they were alive or what may have been the cause of death. Sclerophylly was estimated as specific foliar mass. Out of 72 sampled plant species, 29 presented galls, of which the greatest densities were concentrated on seven host species. A significant increase in sclerophylly with increasing canopy stratum height was observed, but had no direct effect on gall distribution. Total and live galls were more abundant in the canopy than in the understorey for all altitudes but 300 m, where a specific infestation on saplings of the canopy tree Arytera divaricata occurred. We found a positive gall establishment and survivorship in the upper canopy, along with a decrease in chewing herbivory, which resulted in decreasing risks of gall death by herbivory. An overall high sclerophylly rate in both canopy and understorey and the total number of galled host species suggest that the plant community studied is prone to gall establishment and evolution. However, a few hosts species with extreme infestation, such as A. divaricata and Ficus watkinsiana, override the community‐wide effect of sclerophylly. Our results emphasize how scarce and patchy distributed galls are.     

长白山北坡土壤动物群落物种共有度的海拔梯度变化

群落间各生活型土壤动物科及所有土壤动物科的共有度,一定程度上反映了群落间的相关性及沿环境梯度的物种替代关系。应用梯度格局法在长白山北坡海拔550～2650m地段,每隔100m海拔高度设置一块样地,共计22块样地,并应用Jaccard指数,对各海拔不同土壤动物群落间物种共有度的海拔梯度变化进行了分析。结果表明,不同海拔土壤动物群落间物种的共有度,无论以哪一生活层的土壤动物科来表达,基本都以与其最相邻的群落间为最高,群落间物种共有度峰值与谷点反映了群落类型随海拔具有间断性变化。线虫、甲螨、弹尾等各生活型土壤动物的共有度以及所有土壤动物科的共有度,均随着海拔差的增加呈下降趋势,但并非与植被情况完全吻合。     

广西猫儿山沿海拔梯度的叶蜂多样性

在猫儿山自然保护区沿海拔梯度设置7个样地进行叶蜂调查.共采获叶蜂803头,隶属3科58属121种.统计分析表明,异鳞纹眶叶蜂(Claremontia sinobirmana Malaise)和南华平缝叶蜂(Nesoselandria southaWei)为优势种和广布种.不同海拔叶蜂群落的物种丰富度指数、Simpson多样性指数和Shannon-Wiener多样性指数均以中间海拔(1000~1500m)最高,分别为12.293、0.971和3.830;优势度指数则以高海拔最高.聚类分析显示,7个样地的叶蜂物种可以分为高海拔组(>2000m)和其它海拔组(<2000m).相关分析表明,降水量和植被种类是影响叶蜂多样性的主要因素.     

Changes in individual plant traits and biomass allocation in alpine meadow with elevation variation on the Qinghai-Tibetan Plateau

Plant traits and individual plant biomass allocation of 57 perennial herbaceous species, belonging to three common functional groups (forbs, grasses and sedges) at subalpine (3700 m ASL), alpine (4300 m ASL) and subnival (⩾5000 m ASL) sites were examined to test the hypothesis that at high altitudes, plants reduce the proportion of aboveground parts and allocate more biomass to belowground parts, especially storage organs, as altitude increases, so as to geminate and resist environmental stress. However, results indicate that some divergence in biomass allocation exists among organs. With increasing altitude, the mean fractions of total biomass allocated to aboveground parts decreased. The mean fractions of total biomass allocation to storage organs at the subalpine site (7%±2% S.E.) were distinct from those at the alpine (23%±6%) and subnival (21%±6%) sites, while the proportions of green leaves at all altitudes remained almost constant. At 4300 m and 5000 m, the mean fractions of flower stems decreased by 45% and 41%, respectively, while fine roots increased by 86% and 102%, respectively. Specific leaf areas and leaf areas of forbs and grasses deceased with rising elevation, while sedges showed opposite trends. For all three functional groups, leaf area ratio and leaf area root mass ratio decreased, while fine root biomass increased at higher altitudes. Biomass allocation patterns of alpine plants were characterized by a reduction in aboveground reproductive organs and enlargement of fine roots, while the proportion of leaves remained stable. It was beneficial for high altitude plants to compensate carbon gain and nutrient uptake under low temperature and limited nutrients by stabilizing biomass investment to photosynthetic structures and increasing the absorption surface area of fine roots. In contrast to forbs and grasses that had high mycorrhizal infection, sedges had higher single leaf area and more root fraction, especially fine roots.     

青藏高原不同海拔3种菊科植物叶片结构变化及其生态适应性

采用常规石蜡制片技术和显微观察方法,对分布于青藏高原祁连山东部山地冷龙岭3600—4400 m不同海拔高度的蒲公英(Taraxacum mongolicum Hand-Mazz)、火绒草(Leontopodium leontopodioides(Willd.)Beauv)和美丽风毛菊(Saussurea superba Anthony)的叶片形态解剖结构进行了研究,并探讨了其对海拔高度的响应及生态适应性。结果表明:随海拔高度的升高,3种植物气孔器外拱盖内缘、角质层纹饰、气孔与表皮细胞的位置关系以及上、下表皮气孔器内缘呈现不同的变化趋势;火绒草上、下表皮气孔密度随海拔升高而增加,而蒲公英和美丽风毛菊的气孔密度则降低;3种植物上、下表皮气孔指数随海拔高度的增加均未出现规律性变化;3种植物叶片厚度、上下表皮厚度、上下角质层厚度、栅栏细胞系数均随海拔升高而增加;解剖学指标之间大多呈明显的协同进化;叶片结构,尤其是气孔密度对海拔高度变化表现出较大的可塑性。研究表明3种植物采取不同的响应机制来适应海拔高度的变化,植物对高原环境变化的适应具有多样性。     

A comparative anatomical and biochemical analysis in salsola (Chenopodiaceae) species with and without a Kranz type leaf anatomy: a possible reversion of C4 to C3 photosynthesis

Leaf anatomy was studied by light and electron microscopy and the leaf activities of RUBP carboxylase, PEP carboxylase, and malic enzyme were assayed in: Salsola australis and S. oreophila grown on the West Pamirs at 1800 m altitude; in S. australis grown on the East Pamirs at 3860 m; and in S. arbusculiformis grown in the Kisil-Kum desert in Middle Asia near 500 m. Carbon isotope fractionation ratio values also were measured on whole leaf tissue for 18 Salsola species field collected in these and other regions of the former USSR. S. australis leaves are cylindrical and in cross section exhibit a peripheral ring of mesophyll and then an inner ring of bundle sheath type cells; and its biochemical characteristics and deltaC values are typical of a C4 species of the NADP-malic enzyme malate-forming group. These traits were expressed independent of the plant growth altitude up to 4000 m. C4 type deltaC values were obtained in 14 of the Salsola species. Anatomical, structural, and biochemical features typical of the C4 syndrome were absent in S. oreophila and S. arbusculiformis. Four Salsola species, including these two, had C3-type deltaC values. Their cylindrical leaves in cross section exhibited two to three peripheral rings as layers of palisade parenchyma. Although their vascular bundles were surrounded by green bundle sheath cells, their organelle numbers were comparable to those in mesophyll cells. Neither bundle sheath cell wall thickenings nor dimorphic chloroplasts in two leaf cell types were observed. In S. oreophila, there was a high activity of RuBP carboxylase, but a low activity of C4 cycle enzymes. Interpretation of these data lends evidence to the hypothesis that a small group of C3 Salsola species, including S. oreophila, S. arbusculiformis, S. montana, and S. pachyphylla, arose as the result of a reversion of a C4 to a C3 type of photosynthetic CO2 fixation in the cooler climates of Middle Asia.     

圆叶玉兰叶片非结构性碳水化合物与氮、磷含量对海拔的响应

非结构性碳水化合物(non-structural carbohydrates, NSC)、氮(N)和磷(P)是植物生长的重要能源物质和影响植物分布的限制生长因子,圆叶玉兰(Magnolia sinensis)是四川省特有的珍稀濒危极小种群野生植物,研究其NSC、N和P可以反映它的营养供应水平及对环境的适应策略。选取芦山6个海拔梯度(1840,1960,2070,2170,2270,2390 m)的圆叶玉兰为对象,研究不同海拔下圆叶玉兰叶片中NSC与N、P及其化学计量间的关系。结果表明,圆叶玉兰叶片可溶性糖含量在2390 m处显著高于1840 m处, NSC含量在不同海拔差异极显著,随海拔增加呈"低-高-低"的单峰变化,2170 m处叶片NSC含量最高,碳水化合物供应充足;可溶性糖/淀粉的比值随海拔升高呈增大趋势,N含量和N/P比都随海拔上升而下降,且N/P比在各海拔上均小于14,NSC/N比在2390 m处显著高于1840 m处。总之,圆叶玉兰叶片的可溶性糖和NSC含量显著不受海拔的影响,较高的可溶性糖含量有利于抵御低温环境,其生长主要受氮元素限制而不受碳限制,反映了濒危植物圆叶玉兰在其有限的分布范围内NSC及N、P的保护策略,为圆叶玉兰的碳代谢和生长适应对策提供数据基础。