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1.
长白山哈泥泥炭地七种苔藓植物生态位   总被引:2,自引:0,他引:2  
采用Levins和Pianka公式,对哈泥泥炭地7种苔藓植物的生态位进行了研究.结果表明:7种苔藓在泥炭的全氮、全磷、Ca2+、K+、沼泽水的pH和电导率、乔木郁闭度、灌木盖度以及水位埋深9个环境因子梯度上的平均生态位宽度排序为:沼泽皱缩藓>喙叶泥炭藓>中位泥炭藓>尖叶泥炭藓、桧叶金发藓>大泥炭藓>锈色泥炭藓.锈色泥炭藓倾向于特化种,沼泽皱缩藓倾向于泛化种.在各种环境因子中,以电导率平均重叠值最高,水位埋深、乔木郁闭度、pH和灌木盖度梯度上平均重叠值最低,是影响苔藓分布的主要环境因子.多数苔藓在这4个梯度上产生生态位分异.少数苔藓种对在所有环境因子梯度重叠值均较高,是由于苔藓之间存在水分协作关系.这为苔藓植物的种间竞争提供了间接证据.  相似文献   

2.
在金川泥炭地设置1m×1m和25 cm ×25 cm两个尺度的大、小样方进行植被调查,并利用方差比率法、x2检验、Pearson相关分析和Spearman秩相关分析方法,定量分析了9种苔藓植物和30种主要维管植物间的种间关系.偏叶泥炭藓、大泥炭藓和尖叶泥炭藓3种优势苔藓植物彼此呈显著负关联,占领着各自不同的生境;该3种优势苔藓植物同伴生苔藓及维管植物主要呈正相关,形成独特的群落,据此划分出4个生态种组.Spearman秩相关分析表明,大样方741个种对中,正联结种对数占49.53%,明显大于小样方666个种对中的41.14%.样方大小对分析植物个体大小差异悬殊的泥炭地植物群落的种间联结的影响巨大.苔藓与维管植物间以及苔藓植物间的种间联结甚至种间关系应在大、小样方中分别探讨更合适.  相似文献   

3.
贵州思雅河河谷地区喀斯特峰丛石漠苔藓植物群落研究   总被引:3,自引:0,他引:3  
采用样带调查取样法,初步分析贵州思雅河河谷地区的喀斯特石漠区4座受人类活动影响频繁的峰丛以及3个坡段(坡底、坡中、坡顶)上的苔藓植物群落,研究苔藓植物群落在不同峰丛及其不同坡段的分布规律。结果显示:(1)在研究区域内,苔藓植物群落组成有8科19属40种,而且苔藓植物群落分为19个类型,其中纯群落有14个,常见群落有穗枝赤齿藓群落、真藓群落和卷叶湿地藓群落。(2)由于强烈的人类活动造成的干燥、贫瘠的环境,该区域苔藓主要生活型只有矮丛集型和交织型。(3)在这种特殊生境下,苔藓植物群落的丰富性也随着人类干扰范围的增大而减小。(4)在每座峰丛的不同坡段中,穗枝赤齿藓群落有着最大的综合优势比。推测穗枝赤齿藓群落对治理此类人为造成的石漠化生境具有实际应用潜力。  相似文献   

4.
为评估皆伐迹地地表苔藓组成与特点,同时为苔藓生物多样性的保护与恢复提供理论依据,作者于2006年7–10月调查了四川省阿坝藏族羌族自治州地区壤塘二林场云杉(Picealikiangensis var.rubescens)林皆伐迹地自然恢复过程中苔藓植物和维管植物的组成和结构;采用方差分析法对苔藓层结构参数进行差异性检验,对苔藓层结构参数和环境因子作非参数Spearman相关性分析,并对显著性因子进行回归分析。结果表明:(1)在9–27年植被自然恢复过程中,不同阶段苔藓植物群落优势物种组成发生了更替。一些个体较小、易产生孢子、喜阳、抗干扰的顶蒴藓物种侵入并占据优势;而一些出现于早期采伐迹地、喜湿、对环境变化较敏感的侧蒴藓物种消失。(2)随着迹地植被自然恢复,苔藓植物群落物种丰富度、多样性指数和均匀度指数总体上呈下降趋势;迹地上样方间苔藓层盖度和生物量波动较大,但随着自然恢复进程而迅速减少,群落结构趋向简单化;(3)维管植物发育程度与苔藓层发育关系密切;草本层生物量对苔藓盖度和种丰富度起主导作用,草本层高度是对苔藓生物量有显著影响的主导因子。综合分析表明,早期采伐迹地的自然恢复进程中由维管植物群落结构变化导致的生境差异对苔藓植物发育影响较大。  相似文献   

5.
俞英  郭水良  陈建华  方芳 《广西植物》2009,29(4):518-521
研究卵叶泥炭藓(Sphagnumovatum),卷叶凤尾藓(Fissidenscristatus),弯叶灰藓(Hypnumcallichroum)和大金发藓(Polytrichumcommune)的水粗提取液对维管植物虎杖和皱叶酸模种子萌发和幼苗生长的影响。结果显示:四种苔藓植物的粗提取液对两种植物的种子萌发率并没有显著影响。然而,弯叶灰藓,、卵叶泥炭藓和卷叶凤尾藓的提取液抑制了皱叶酸模种子的活力指数。除此之外,卷叶凤尾藓还显著地抑制了它幼苗的干重。四种藓类的提取液对虎杖的种子活力指数和干重,但是卷叶凤尾藓的提取液对幼苗的生长有显著的影响。苔藓植物粗提取液对种子萌发和幼苗生长的影响的机制并不清楚,有待进一步研究。  相似文献   

6.
泥炭藓是北方泥炭地的优势植物,其高光谱特征研究很少。本研究采用高光谱遥感技术,对不同水位埋深条件下(藓丘及丘间)生长的相同种类泥炭藓植物,及同一水位埋深条件下的不同种类泥炭藓植物的光谱特征进行研究。结果表明,不同种类泥炭藓属植物的光谱反射特征具有明显种间差异,主要反映在绿峰、红边的差异上。由于水分条件差异,生长在高丘和低丘的锈色泥炭藓、泥炭藓及中位泥炭藓在可见光和近红外波段的光谱反射率均具有显著差异,高丘的泥炭藓属植物的反射率均高于低丘的泥炭藓属植物。本研究所获得的东北地区哈泥泥炭地几种泥炭藓属植物的详细光谱信息,可以为高分辨率航空影像和卫片解译泥炭藓湿地提供地面基础。  相似文献   

7.
为探究神农架大九湖泥炭藓湿地的关键物种大泥炭藓(Sphagnum palustre L.)种群的分布特征及其制约因素,于2020年8月沿垂直湖岸带方向设置样带和样方进行植被和环境因子的调查和采样,于室内进行各理化指标和生理指标的测定与分析。研究结果显示:(1)大泥炭藓三生长指标(头状枝数量、盖度、生物量)对垂直湖岸带距离的响应具有一致性,均随垂直湖岸带距离的增加呈现先增加后减小的趋势,在距湖岸40m左右时,大泥炭藓种群生产力最高;(2)多元线性回归分析结果显示,在20个环境因子(土壤含水量、容重、孔隙度、固相比、液相比、气相比、pH、TN、TP、TOC、AHN、AP、TOC/TN、TOC/TP、TN/TP;地下水埋深;水样pH、TN、TP、TN/TP)中,地下水埋深是影响大泥炭藓种群生长和分布的最重要环境因子,其次是土壤TOC/TP;在8个生理指标(组织TC、TN、TP、TC/TN、TC/TP、TN/TP、总叶绿素、类胡萝卜素)中,组织TC与大泥炭藓生长显著相关;(3)地下水埋深通过影响大泥炭藓头状枝的光合和呼吸作用,土壤TOC通过影响大泥炭藓吸收同化到自身组织中的TC含量,来影响其种...  相似文献   

8.
贵州贞丰喀斯特石漠峰丛苔藓植物群落生态特征   总被引:8,自引:1,他引:7  
调查和分析了贵州贞丰县喀斯特石漠地区的3座典型峰丛、3个山段上苔藓植物群落的种类组成及其生态特征。研究区域内,苔藓植物群落的种类组成有12科16属19种。苔藓植物群落共21个类型,其中纯群落占83.3%,两种及两种以上苔藓组成的群落占26.7%,占优势的群落是皱叶牛舌藓群落(Anomodetum)、卷叶湿地藓群落(Hyophiletum)和卷叶毛口藓群落(Trichostometum)。苔藓植物群落物种为适应旱生、干燥和强光直射的环境,生活型仅有交织型和矮丛集型两类。由于人类强烈的活动破坏了原有的生态系统,苔藓群落的分布在石漠峰丛中显示出了特异性,苔藓群落的丰富度为山顶>山腰>山脚。各山段的皱叶牛舌藓群落均有最大的生态优势度,具有治理石漠的潜在价值。  相似文献   

9.
适量的烟气能够促进有性繁殖体萌发,但迄今尚无辅助烟气处理探究孢子生活力快速检测方法的研究报道。该文选择毛缘泥炭藓(Sphagnum fimbriatum)、中位泥炭藓(S.magellanicum)和粗叶泥炭藓(S.squarrosum)作为材料,分别使用亚甲基蓝染色法、四唑(TTC)染色法、碘-碘化钾(I2-KI)染色法和红墨水染色法对泥炭藓孢子进行染色,并比照营养液、烟溶液+营养液培养的孢子萌发试验,对比研究泥炭地苔藓植物孢子生活力快速检测的最佳方法。结果表明:亚甲基蓝染色法的染色效果最为明显,TTC和I2-KI均未能使泥炭藓孢子着色,孢子对红墨水虽有着色反应但不清晰;与营养液培养相比,添加烟溶液使毛缘泥炭藓、中位泥炭藓和粗叶泥炭藓孢子萌发率分别提高5%、5%和18%;使用亚甲基蓝染色的孢子染色率与经烟溶液处理过的孢子萌发率最为接近。综上认为,亚甲基蓝染色法能快速检测泥炭藓孢子的生活力。  相似文献   

10.
北京市区苔藓植物空间分布与环境关系的研究   总被引:3,自引:0,他引:3  
在2006年10月至2007年10月期间,对北京市五环路内及附近部分区域的苔藓群落进行了调查,共调查了31个地点、164个样地,采集苔藓植物标本327份。经整理鉴定,调查区有苔藓植物12科24属55种,其中阔叶小石藓(Weisia planifolia)和立碗藓(Physcomitrium sphaericum)等种类为调查区的广布种。通过对调查区同类型、不同地点苔藓植物多样性指数分析,发现北京市苔藓植物的分布特点为城西、城北苔藓植物多样性高于城东、城南。用典范对应分析法(CCA)分析27个样地中的20种地面生苔藓植物的盖度与主要环境因子的关系,结果表明,土壤含水量、距主干道距离、人为踩踏、土壤pH值、林木郁闭度等环境因子对北京市苔藓植物的分布有显著影响,其中土壤含水量、土壤pH值对苔藓植物分布的影响最为显著,北京市区大多数常见苔藓种类喜生于土壤含水量较高、偏酸性的环境。  相似文献   

11.
影响广东黑石顶树附生苔藓分布的环境因子   总被引:2,自引:0,他引:2  
通过对广东省黑石顶自然保护区内5个2500 m2样地内树附生苔藓的调查及有关环境因子的测定,研究了树附生苔藓的分布格局及其与环境因子的关系.树附生苔藓在不同高度的分布存在一定梯度,20 cm高处树附生苔藓的种类数与盖度均大于60 cm及更高处,且其群落优势种的数量组成与后者存在较大差异.不同树种附生苔藓盖度和种数差异较大.基于附生苔藓植物的盖度进行DCA排序及聚类分析将树种分成四组,马尾松(Pinus massoniana)因具有两种特有的网藓(巴西网藓Syrrhopodon prolifer和鞘刺网藓S.armatus)单独一组,福建青冈(Quercus chungii)亦与其余各种的差异均较大,形成一组,其余阔叶树种根据其所处的森林类型分成两组,针阔叶混交林内的阔叶树种和次生阔叶林内的阔叶树种各形成一组.对环境因子及树皮含水量和pH的分析显示,垂直梯度上空气湿度的差异可能是造成附生苔藓在不同高度分布差异的主要影响因子之一,不同树种附生苔藓的差异在一定程度上受树皮pH的影响,而与树皮含水量无关.同一树种上树附生苔藓的分布又在一定程度上受森林类型的影响.  相似文献   

12.
It has been suggested that a heterogeneous environment enhances species richness and allows for the coexistence of species. However, there is increasing evidence that environmental heterogeneity can have no effect or even a negative effect on plant species richness and plant coexistence at a local scale. We examined whether plant species richness increases with local heterogeneity in the water table depth, microtopography, pH and light availability in a swamp forest community at three local spatial scales (grain: 0.6, 1.2 and 11.4 m). We also used the variance partitioning approach to assess the relative contributions of niche-based and other spatial processes to species occurrence. We found that heterogeneity in microtopography and light availability positively correlated with species richness, in accordance with the habitat heterogeneity hypothesis. However, we recorded different heterogeneity-diversity relationships for particular functional species groups. An increase in the richness of bryophytes and woody plant species was generally related to habitat heterogeneity at all measured spatial scales, whereas a low impact on herbaceous species richness was recorded only at the 11.4 m scale. The distribution of herbaceous plants was primarily explained by other spatial processes, such as dispersal, in contrast to the occurrence of bryophytes, which was better explained by environmental factors. Our results suggest that both niche-based and other spatial processes are important determinants of the plant composition and species turnover at local spatial scales in swamp forests.  相似文献   

13.
We investigated the importance of water chemistry and water regime for vascular plant and bryophyte species distribution in Western Carpathian mires dominated bySphagnum. Seventy-seven small circle plots distributed across a wide geographical area, a wide range of mineral richness and all possible microtopographical features were sampled in terms of species composition, physical-chemical water properties and water regime during one growing season. Both water chemistry and water regime were found to be important factors for vegetation composition. Bryophytes reflected only one clear gradient, connected to base-richness (pH, conductivity) and maximal water-level, whereas three different environmental gradients determined the occurrence of vascular plants: water-level amplitude, base-richness and an indistinct gradient presumably connected to peat layer thickness. When the entire data set was subjected to DCA ordination, the first resulting axis was governed by the bryophyte subset, whereas the second one was governed by the vascular plant subset. The species density of vascular plants was positively correlated with pH and conductivity. On the contrary, bryophyte species density showed no relationship to environmental factors. We further compared the pH values measured in groundwater and in water squeezed from bryophytes from the same plot; these plots were distributed along the base-richness gradient. Only in the acidic mires did the use of squeezed-water chemistry in the analyses give results similar to the use of groundwater pH. Further, we found thatSphagnum species with a similar response to the base-richness gradient had differentiated niches with respect to the water level gradient and vice versa.Sphagnum contortum andS. warnstorfii exhibiting the same demands for groundwater pH were segregated along the gradient of maximum water level. An analogous pattern was detected for acidophilous speciesSphagnum magellanicum andS. papillosum.  相似文献   

14.
Questions: 1. Indicator values, such as those of Ellenberg, for different environmental factors are seen as independent. We tested for the presence of interactions between environmental factors (soil moisture and reaction) to see if this assumption is simplistic. 2. How close are Ellenberg indicator values (IV s) related to the observed optima of species response curves in an area peripheral to those where they have been previously employed and 3. Can the inclusion of bryophytes add to the utility of IVs? Location: South Uist, Outer Hebrides, Scotland, UK. Methods: Two grids (ca. 2000 m × 2000 m) were sampled at 50‐m intervals across the transition from machair to upland communities covering an orthogonal gradient of both soil pH (reaction) and soil moisture content. Percentage cover data for vascular plants, bryophytes and lichens were recorded, along with pH and moisture content of the underlying sand/soil/ peat. Reaction optima, derived from species response curves calculated using HOF models, were compared between wet and dry sites, and moisture optima between acidic and basic samples. Optima for the whole data set were compared to Ellenberg IVs to assess their performance in this area, with and without the inclusion of bryophytes. Results: A number of species showed substantially different pH optima at high and low soil moisture contents (18% of those tested) and different soil moisture optima at high and low pH (49%). For a number of species the IVs were poor predictors of their actual distribution across the sampled area. Bryophytes were poor at explaining local variation in the environmental factors and also their inclusion with vascular plants negatively affected the strength of relationships. Conclusions: A substantial number of species showed an interaction between soil moisture and reaction in determining their optima on the two respective gradients. It should be borne in mind that IVs such as Ellenberg's may not be independent of one another.  相似文献   

15.
We studied the relative importance of local habitat conditions and landscape structure for species richness of vascular plants, bryophytes and lichens in dry grasslands on the Baltic island of Öland (Sweden). In addition, we tested whether relationships between species richness and vegetation cover indicate that competition within and between the studied taxonomic groups is important. We recorded species numbers of vascular plants, bryophytes and lichens in 4 m2 plots (n=452), distributed over dry grassland patches differing in size and degree of isolation. Structural and environmental data were collected for each plot. We tested effects of local environmental conditions, landscape structure and vegetation cover on species richness using generalized linear mixed models. Different environmental variables explained species richness of vascular plants, bryophytes and lichens. Environmental effects, particularly soil pH, were more important than landscape structure. Interaction effects of soil pH with other environmental variables were significant in vascular plants. Plot heterogeneity enhanced species richness. Size and degree of isolation of dry grassland patches significantly affected bryophyte and lichen species richness, but not that of vascular plants. We observed negative relationships between bryophyte and lichen species richness and the cover of vascular plants. To conclude, effects of single environmental variables on species richness depend both on the taxonomic group and on the combination of environmental factors on a whole. Dispersal limitation in bryophytes and lichens confined to dry grasslands may be more common than is often assumed. Our study further suggests that competition between vascular plants and cryptogams is rather asymmetric.  相似文献   

16.
Sphagnum cuspidatum , S. magellanicum and S. rubellum are three co-occurring peat mosses, which naturally have a different distribution along the microtopographical gradient of the surface of peatlands. We set out an experiment to assess the interactive effects of water table (low: −10 cm and high: −1 cm) and precipitation (present or absent) on the CO2 assimilation and evaporation of these species over a 23-day period. Additionally, we measured which sections of the moss layer were responsible for light absorption and bulk carbon uptake. Thereafter, we investigated how water content affected carbon uptake by the mosses. Our results show that at high water table, CO2 assimilation of all species gradually increased over time, irrespective of the precipitation. At low water table, net CO2 assimilation of all species declined over time, with the earliest onset and highest rate of decline for S. cuspidatum . Precipitation compensated for reduced water tables and positively affected the carbon uptake of all species. Almost all light absorption occurred in the first centimeter of the Sphagnum vegetation and so did net CO2 assimilation. CO2 assimilation rate showed species-specific relationships with capitulum water content, with narrow but contrasting optima for S. cuspidatum and S. rubellum . Assimilation by S. magellanicum was constant at a relatively low rate over a broad range of capitulum water contents. Our study indicates that prolonged drought may alter the competitive balance between species, favoring hummock species over hollow species. Moreover, this study shows that precipitation is at least equally important as water table drawdown and should be taken into account in predictions about the fate of peatlands with respect to climate change.  相似文献   

17.
以中位泥炭藓(Sphagnum magellanicum Brid.)为研究对象,分别从实测冠层光谱和遥感传感器模拟光谱层面分析其群落的光谱特征。研究结果显示,中位泥炭藓与北方针叶林光谱差异明显,最佳光谱识别区间为740~1140 nm和1230~1412 nm。在可见光波段上,中位泥炭藓与云杉(Picea engelmannii Parry ex Engelmann)和黑松(Pinus contorta Douglas ex Loudon)的绿峰位置有所差异。水竹(Phyllostachys heteroclada Oliver)和中位泥炭藓的光谱识别特征波段集中在可见光-近红外波段,分别为400~550、560~696、1025~1143 nm。中位泥炭藓与北方针叶林以及水竹的特征光谱区间存在细微差异,且与水竹在可见光波段有较好的可分性,因此不同纬度带上中位泥炭藓群落的特征谱宽有所差异。红外波段是中位泥炭藓识别的最佳光谱区间。在多光谱遥感水平上,中位泥炭藓识别效果较好,传感器的识别能力依次为:MSI > ALI > OLI > ASTER。在2个中位泥炭藓群落的光谱特征分析中,导数、对数、包络线去除法的光谱降维能力有所差异,其中包络线去除法效果最好。  相似文献   

18.
The environmental factors correlating with community structure of vegetation on talus slopes of the 785 km long Niagara Escarpment, southern Ontario, Canada, were studied using canonical correspondence and regression analysis. The bryophytes and higher vascular plants were analysed separately to see if their responses were similar or different. Both vascular plants and bryophytes responded similarly to the environmental variables that were measured. For both vegetation components, location from north to south explained most of the variance. When species richness was plotted against location for the complete vegetation and for the two components separately, the results showed that vascular plant species richness decreased with increasing latitude, while bryophyte richness increased. The magnitude of both of these trends was slight but consistent with the hypothesis that available environmental energy governs a significant amount of the variance in species richness. Since separate components of the talus vegetation were shown to respond differently to the same environmental variable, groups of taxa should not be excluded from community level studies without a consideration of the possible consequences of this bias.  相似文献   

19.
以中位泥炭藓(Sphagnum magellanicum Brid.)为研究对象,分别从实测冠层光谱和遥感传感器模拟光谱层面分析其群落的光谱特征。研究结果显示,中位泥炭藓与北方针叶林光谱差异明显,最佳光谱识别区间为740~1140 nm和1230~1412 nm。在可见光波段上,中位泥炭藓与云杉(Picea engelmannii Parry ex Engelmann)和黑松(Pinus contorta Douglas ex Loudon)的绿峰位置有所差异。水竹(Phyllostachys heteroclada Oliver)和中位泥炭藓的光谱识别特征波段集中在可见光-近红外波段,分别为400~550、560~696、1025~1143 nm。中位泥炭藓与北方针叶林以及水竹的特征光谱区间存在细微差异,且与水竹在可见光波段有较好的可分性,因此不同纬度带上中位泥炭藓群落的特征谱宽有所差异。红外波段是中位泥炭藓识别的最佳光谱区间。在多光谱遥感水平上,中位泥炭藓识别效果较好,传感器的识别能力依次为:MSI> ALI> OLI> ASTER。在2个中位泥炭藓群落的光谱特征分析中,导数、对数、包络线去除法的光谱降维能力有所差异,其中包络线去除法效果最好。  相似文献   

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