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1.
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   

2.
兜叶藓属Horikawaea是典型的东南亚特有属,该属共有3个种,目前这3个种在中国均有发现。从分布范围来看,该属分布的北缘是西藏的墨脱县,南缘是菲律宾群岛一带。兜叶藓Horikawaea nitida在贵州麻阳河黑叶猴自然保护区的发现也是该种在贵州分布的首次记录。根据采自贵州该属植物的标本,描述并讨论了该属的地理分布与属内亲缘关系。  相似文献   

3.
兜叶藓属Horikawaea是典型的东南亚特有属,该属共有3个种,目前这3个种在中国均有发现。从分布范围来看,该属分布的北缘是西藏的墨脱县,南缘是菲律宾群岛一带。兜叶藓Horikawaea nitida在贵州麻阳河黑叶猴自然保护区的发现也是该种在贵州分布的首次记录。根据采自贵州该属植物的标本,描述并讨论了该属的地理分布与属内亲缘关系。  相似文献   

4.
王晓宇  熊源新 《广西植物》2003,23(4):309-310,308
大帽藓科(Encalyptaceae)植物世界有两属,中国仅1属,即大帽藓属(Encalypta Hedw.),共记录有10种。通过对采自贵州省西北部的2份标本的鉴定,认为此标本为扭蒴大帽藓(新拟名)(Encalypta strepto-carpa Hedw.),是中国首次发现的一新记录种。本种属于北温带分布类型的植物,贵州是其分布的南缘。  相似文献   

5.
本研究选取贵州都匀市毛尖镇螺蛳壳风景区沼泽湿地的6种泥炭藓属(Sphagnum)植物,分别测量其主茎粗、株高,计数侧枝数和分枝数,并计算其饱和吸水率、外吸水率、内吸水率、透明细胞面积占比、侧枝密度等指标.结果显示:(1)6种泥炭藓饱和吸水率大小依次为狭叶泥炭藓(S.cuspidatum Ehrh)(2518.99%)>...  相似文献   

6.
基于GIS和MaxEnt比较中国砂藓属与紫萼藓属植物地理分布   总被引:3,自引:0,他引:3  
基于19个生物气候因子和紫萼藓属(Grimmia) 172个、砂藓属(Racomitrium) 181个国内分布记录,应用MaxEnt模型和ArcGis 9.3软件,定量预测了紫萼藓属与砂藓属植物在“属”水平上在我国各省区的生境适应性特点.预测结果表明,紫萼藓属植物在浙江(0.7099,综合生境适宜性指数,下同)、江苏(0.6212)、北京(0.5987)、天津(0.5648)、云南(0.5532)、辽宁(0.5515)、台湾(0.5422)、安徽(0.5398)和吉林(0.4945)有较高的气候适应性,而砂藓属植物在浙江(0.889)、上海(0.6564)、香港(0.5897)、台湾(0.5858)、贵州(0.5354)、湖北(0.5039)、云南(0.4885)、重庆(0.4871)、江苏(0.4793)和安徽(0.4552)具有较高的生境适宜性.对砂藓属与紫萼藓属的分布预测范围进行比较发现,砂藓属植物在香港、重庆、贵州、广东、广西、湖北、海南和台湾的生境适应性比紫萼藓属的总体上要高,而在江西、福建和湖南,两属的分布概率比较接近,其余省区则紫萼藓属植物的生境适宜性比砂藓的要高.紫萼藓属植物属于典型的温带性种类,其分布主要在高海拨的寒冷地段.  相似文献   

7.
泥炭藓属(Sphagnum)植物的持水特性在泥炭湿地形成过程中起着重要作用,研究其与土壤营养元素之间的关系有助于地区湿地保护和退化湿地的修复。以贵州麻若平台分布的泥炭沼泽为对象,采用方差分析、相关性分析和冗余分析等方法对沼泽内泥炭藓的生物量、蓄水量、吸水率和土壤营养元素含量等进行研究。结果显示,该区域泥炭藓物种组成主要包括狭叶泥炭藓(Sphagnum cuspidatum Ehrh.)、多纹泥炭藓(Sphagnum multifibrosum X.J.Li&M.Zang)和卵叶泥炭藓(Sphagnum ovatum Hampe.)3种,狭叶泥炭藓为优势种,占泥炭藓总盖度的87.2%。沼泽中泥炭藓的生物量为(0.62 ±0.01)kg/m2,自然蓄水量为(9.42 ±0.45)kg/m2,饱和吸水率达1827.41%±34.56%,说明泥炭藓具有很强的持水能力。RDA分析表明,泥炭藓的生物量、饱和吸水量和饱和吸水率主要受沼泽土壤总钾、总磷、有效磷、有效氮、有效钾的影响,泥炭藓的鲜重、自然蓄水量和自然吸水率受土壤pH和水位的影响较大。泥炭藓的生物量、饱和蓄水量、饱和吸水率与土壤总钾含量呈正相关,与土壤总磷、有效磷、总钾、有效氮、总氮、有机质含量呈负相关,说明土壤总磷、有效磷、有效钾、有效氮、总氮、有机质对沼泽中泥炭藓的持水能力具有抑制作用。  相似文献   

8.
泥炭藓植物数量分类的研究   总被引:3,自引:0,他引:3  
何小兰  敖志文 《植物研究》1989,9(4):135-144
本文用聚类分析和主成分分析方法对泥炭藓属的14个种及一个变种进行了数量分类的研究。通过对15个OTU×42个性状的原始数值矩阵的标准化及复杂运算后,其结果表明: 1.由聚类过程所得到的树系图,并结合生物分类学的实际意义,将泥炭藓属分为6个组,即Section Sphagnum、Sect.Squarrosa、Sect.Acutifolia、Sect.Subse-cunda、Sect.Polyclada及Sect.Cuspidata。其结果与经典分类的结果基本上是一致的。 2.通过对泥炭藓主要性状的因子分析和主成分排序,初步反映了各性状所占的信息比例,找出了泥炭藓植物分类中所应依据的重要性状。 3.通过对泥炭藓植物的排序,进一步阐明了泥炭藓属内的各个种之间的系统位置。 本文首次将数量分类用于泥炭藓植物,通过研究,认为该方法用于其它苔藓植物也是可行的,这对苔藓植物定量地、准确地表现分类群的系统位置及亲缘关系,将有一定的参考价值。  相似文献   

9.
泥炭藓属(Sphagnum)植物的持水特性在泥炭湿地形成过程中起着重要作用,研究其与土壤营养元素之间的关系有助于地区湿地保护和退化湿地的修复。以贵州麻若平台分布的泥炭沼泽为对象,采用方差分析、相关性分析和冗余分析等方法对沼泽内泥炭藓的生物量、蓄水量、吸水率和土壤营养元素含量等进行研究。结果显示,该区域泥炭藓物种组成主要包括狭叶泥炭藓(Sphagnum cuspidatum Ehrh.)、多纹泥炭藓(Sphagnum multifibrosum X. J. LiM. Zang)和卵叶泥炭藓(Sphagnum ovatum Hampe.) 3种,狭叶泥炭藓为优势种,占泥炭藓总盖度的87.2%。沼泽中泥炭藓的生物量为(0.62±0.01) kg/m~2,自然蓄水量为(9.42±0.45) kg/m~2,饱和吸水率达1827.41%±34.56%,说明泥炭藓具有很强的持水能力。RDA分析表明,泥炭藓的生物量、饱和吸水量和饱和吸水率主要受沼泽土壤总钾、总磷、有效磷、有效氮、有效钾的影响,泥炭藓的鲜重、自然蓄水量和自然吸水率受土壤pH和水位的影响较大。泥炭藓的生物量、饱和蓄水量、饱和吸水率与土壤总钾含量呈正相关,与土壤总磷、有效磷、总钾、有效氮、总氮、有机质含量呈负相关,说明土壤总磷、有效磷、有效钾、有效氮、总氮、有机质对沼泽中泥炭藓的持水能力具有抑制作用。  相似文献   

10.
以泥炭藓属(Sphagnum)植物为优势种的贫营养泥炭地是陆地生态系统重要的碳汇,其优势植物的生长与分解动态关系着贫营养泥炭地碳汇潜力,但有关氮沉降对贫营养泥炭地优势藓类植物生长与分解的影响还存在很大争议,并且氮沉降对亚热带贫营养泥炭地优势藓类植物生长与分解的研究鲜有报道。该研究以鄂西南贫营养泥炭地为研究对象,通过原位喷洒不同浓度的NH4Cl溶液,采用生物量收割法和分解袋法,探讨模拟氮沉降对泥炭藓(S.palustre)与金发藓(Polytrichumcommune)生长及分解的影响。研究结果表明:(1)氮沉降对两种藓类植物生长高度与生物量均有明显的影响,且两种藓类植物生长存在一定的氮沉降阈值,约为3g·m–2·a–1;(2)氮沉降对两种藓类植物生长影响程度不同,金发藓对氮沉降的响应灵敏度要大于泥炭藓;(3)高浓度氮沉降(6和12g·m–2·a–1)抑制了泥炭藓分解,低浓度氮沉降(3g·m–2·a–1)对泥炭藓分解的影响取决于分解时间,而所有浓度氮沉降均抑...  相似文献   

11.
This paper documents the occurrence of allotriploidy (having three differentiated genomes) in gametophytes of two Southern Hemisphere Sphagnum species ( S. australe, S . falcatulum ). The pattern of microsatellite alleles indicates that both species are composed of a complex of allodiploid and allotriploid gametophytes, with the latter resulting from two allopolyploidization events. No haploid ( n  =  x ) gametophytes were found for either species. The ploidal levels suggested by the pattern of microsatellite alleles were confirmed by flow cytometry and Feulgen DNA image densitometry. For both S. australe and S. falcatulum , the respective allodiploid plants (or their ancestors) are one of the parent species of the allotriploid plants. This is the first report of triploidy in Sphagnum gametophytes occurring in nature and also the first report of the presence of three differentiated genomes in any bryophyte. It is also the first report of intersectional allopolyploidy in Sphagnum , with S. australe appearing to have parental species from Sphagnum sections Rigida and Sphagnum, and S. falcatulum having parental species from Sphagnum sections Cuspidata and Subsecunda . In both species, the allotriploid cytotypes were the most prevalent cytotype on the South Island of New Zealand. The pattern of microsatellite alleles shows the presence of two genetically distinct populations of allodiploid S. australe , possibly indicating multiple origins of polyploidy for that allodiploid cytotype. Morphological evidence is also highly indicative of recurrent polyploidy in the allotriploid cytotype of S. falcatulum . Allopolyploidy has clearly played a major evolutionary role in these two Southern Hemisphere taxa. This study, in conjunction with other recent research, indicates that allopolyploidy is a common, if not the predominant, form of polyploidy in Sphagnum .  相似文献   

12.
Experimental evidence for a persistent spore bank in Sphagnum   总被引:1,自引:0,他引:1  
Spore capsules of four Sphagnum species were buried at different depths in peat on a bog. Spore viability was determined after 0, 1, 2 and 3 yr. Viability generally declined with time, but viable spores were still found at all depths after 3 yr. The light-coloured spores of S. balticum and S. tenellum retained their viability better than the darker spores of S. fuscum and S. lindbergii . Survival was highest under wet but aerobic conditions, but was also high under humid or periodically desiccated conditions. By contrast, most spores stored under wet, anaerobic conditions died within 2–3 yr. These results, and predictions from them, are not consistent with earlier results for spores of long-lived and dominant bryophytes, or for seeds of phanerogams of undisturbed wetlands and forests. There was no correlation between spore size and longevity across species, but the small spores from small capsules of S. balticum and S. tenellum generally showed higher viability than those from the medium-sized and large capsules of the same species. This suggests a positive intraspecific relationship between longevity and dispersal distance. There was an indication of conditional dormancy, controlled by weather, in Sphagnum spores. The experiments indicate that Sphagnum spores can form a long-term persistent spore bank under suitable conditions, with a half-life of between 1 and 20 yr (mean across species of 2.6 and 5.0 yr at two depths studied), and with potential values in individual spore capsules of several decades, or even of centuries. Sphagnum spores kept refrigerated showed 15–35% viable spores after 13 yr. The capacity to form a persistent spore bank that can be activated whenever favourable conditions occur might help explain the wide geographical distribution of many Sphagnum species in the boreal and temperate zones, where they have managed to colonize almost every suitable patch of acidic, nutrient-poor wetland.  相似文献   

13.
The class Sphagnopsida (Bryophyta) includes two genera: Ambuchanania and Sphagnum. Ambuchanania contains just one rare species known from two Tasmanian localities, but Sphagnum comprises a speciose clade of mosses that dominates many wetland ecosystems, especially in the boreal zone of the Northern Hemisphere. Recent phylogenetic analyses have resolved well-supported clades within Sphagnum, but polarizing Sphagnum evolution has been problematic because the genus is so isolated that it is difficult to determine homologies between morphological and/or molecular traits within Sphagnum with those of any potential outgroup. DNA sequences from 16 genomic regions representing the mitochondrial, chloroplast, and nuclear genomes (ca. 16 kilobases) were obtained from 24 species of Sphagnum plus one species each from Takakia and Andreaea in order to resolve a rooted phylogeny. Two tropical species, S. sericeum and S. lapazense, were resolved as sister to the rest of the genus and are extremely divergent from all other sphagna. The main Sphagnum lineage consists of two clades; one includes the sections Sphagnum, Rigida, and Cuspidata, and the other includes Subsecunda, Acutifolia, and Squarrosa. The placement of section Subsecunda is weakly supported, but other nodes are strongly supported by maximum parsimony, maximum likelihood, and Bayesian analyses. In addition to homogeneous Bayesian analyses, heterogeneous models were employed to account for different patterns of nucleotide substitution among genomic regions.  相似文献   

14.
Several complexes of species in Sphagnum (peat mosses) originated through hybridization and allopolyploidy, suggesting that these processes have played a major evolutionary role in this genus. The Sphagnum subsecundum complex includes gametophytically haploid and diploid species in North America. Analyses of 12 microsatellite loci and sequences from two plastid DNA markers show that the evolutionary history of this group is substantially more complex than previously thought. Two taxonomic species, Sphagnum lescurii and Sphagnum inundatum, include both haploid and diploid populations. Within each ploidal level, S. lescurii and S. inundatum are not genetically differentiated. The diploid taxa show patterns of fixed heterozygosity for the microsatellite markers, consistent with an allopolyploid origin. Diploid S. lescurii is an allopolyploid between haploid S. lescurii and (haploid) S. subsecundum. Sphagnum carolinianum is an allopolyploid between haploid S. lescurii and an unknown parent. We detected homoploid hybridization between the haploids Sphagnum contortum and S. subsecundum. Finally, we report three samples of diploid Sphagnum platyphyllum (otherwise haploid) that have an allopolyploid origin involving north‐eastern haploid S. platyphyllum and an unidentified taxon. © 2010 The Linnean Society of London, Biological Journal of the Linnean Society, 2010, 99 , 135–151.  相似文献   

15.
简述了小腹茧蜂亚科陡胸茧蜂属的研究历史、现状和形态特征,描述了该属2新种:贵州陡胸茧蜂Snellenius guizhouensis sp.nov.和宽颊陡胸茧蜂Snellenius latigenus sp.nov,并与其近似种做了比较.两新种均采自贵州省,模式标本存放于贵州师范大学地理与生物科学学院.  相似文献   

16.
Sphagnum magellanicum has been viewed as being a predominantly circumpolar species in the northern hemisphere, but it occurs in the southern hemisphere and was originally described from the southern parts of Chile. It is an ecologically important species in mire ecosystems and has been extensively used as a model to study processes of growth, carbon sequestration and peat decomposition. Molecular and experimental studies have, however, revealed genetic structure within S. magellanicum, and morphological differences associated with these genetic groups. Here we describe Sphagnum divinum in Sphagnum subgenus Sphagnum (Sphagnaceae, Bryophyta) as a new species, based on molecular and morphological evidence. Sphagnum medium is reinstated as a distinct species and is epitypified. Consequently, a new species concept of S. magellanicum is presented including an epitypification. Important morphological characters to separate these three species in the field and under the microscope are presented. Ecology and distribution differ among the species; S. divinium has a wide habitat range including mire margin, forested peatlands and moist heaths, and a circumpolar distribution around the northern hemisphere. Sphagnum medium seems to be more restricted to ombrotrophic mire expanse habitats and shows an amphi-Atlantic distribution in the northern hemisphere. Sphagnum magellanicum has a very broad ecological niche in peatlands and is found in most mire habitats in Tierra del Fuego on the southern tip of South America.  相似文献   

17.
记述了采自贵州的隐脉叶蝉亚科拟隐脉叶蝉属一新种,剑突拟隐脉叶蝉Sophonia spathulard sp. n。模式标本保存在贵州大学。  相似文献   

18.
Based on morphological evidence it has been hypothesised that Sphagnum jensenii is an allopolyploid, with S. annulatum and S. balticum as progenitors. Analysis of nine putative enzyme loci carried out on populations of these three species from central Norway, strongly corroborate this hypothesis. Sphagnum jensenii showed fixed heterozygosity at four of the loci suggesting that it is an allopolyploid. At each of the loci screened, extant populations of S. annulatum and S. balticum shared alleles with S. jensenii . The taxonomic interpretation is that S. jensenii should be recognised as a distinct species different from S. annulatum . Implications of allopolyploidy on ecological tolerances and niche breadth are briefly discussed.  相似文献   

19.
1990年8月对梵净山和张家界两个自然保护区内蜘蛛群落进行调查,结果表明:自然保护区内蜘蛛资源极为丰富,经初步鉴定,计有蜘蛛27科85属180种,其中主要成分依次为肖蛸、园蛛、狼蛛、球蛛和皿蛛等。蜘蛛发生量折合每亩为17,585—54,000头。八个不同生境类型蜘蛛群落的种类数和密度存在明显差异;各种蜘蛛分布群在群落内的比例随栖息地结构变化而改变,因而也导致蜘蛛群落的Shannon-Wiener多样性指数,Simpson优势度和均等度等参数的变化。  相似文献   

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