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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.
泥炭植物残体是泥炭和泥炭矿体的主要组分。泥炭的植物组成与泥炭的分解度和营养状况密切相关。在进行泥炭分类时,植物残体组成是其重要依据。各泥炭矿体特征间“质”的差异也反映在泥炭植物残体组成成分的不同上。因此,在进行泥炭矿体分类时,可将矿层的植物残体组分作其依据。本文拟将我国的泥炭矿体分为富营养、中营养、贫营养和混合四个泥炭矿体型;并续分出十一个泥炭矿体组。  相似文献   

3.
冯璐  卜兆君  李振新  冯亚敏 《生态学报》2015,35(9):2993-2997
长寿有性繁殖体对于植物种群的长存具有重要意义,迄今,泥炭地苔藓植物孢子长寿性研究还很少。在长白山哈泥泥炭地钻取丘间表层泥炭样品,测定泥炭腐殖化度和烧失量,逐层提取和培养泥炭藓孢子,研究埋藏时间对孢子萌发的影响。结果表明,丘间泥炭藓孢子埋藏环境中,随着埋深的增加即埋藏年限的增加,泥炭腐殖化度和烧失量总体上分别呈现增加和递减的趋势,而地层泥炭藓孢子萌发率呈现直线递减的规律,但在埋藏近150余年后孢子萌发率仍可达40%。研究进一步证明泥炭藓具有长期持久孢子库,根据推算,泥炭地丘间埋藏环境中,泥炭藓孢子最大寿命可超过400a。  相似文献   

4.
研究泥炭地特征性环境因子——淹水、少氧和化感物质对泥炭藓孢子持久性的影响, 可深入理解泥炭地泥炭藓持久孢子库的形成机制, 为退化泥炭地泥炭藓地被恢复研究提供参考。该研究以藓丘种和丘间种两种泥炭藓的孢子为试验材料, 通过室内模拟控制实验的方法, 研究泥炭藓孢子在空气、超纯水、泥炭地地表水和泥炭藓沥出液中, 及3种速率充气下, 孢子萌发力持久性的变化。经充气处理后, 泥炭藓孢子持久性显著低于不充气处理。不充气时, 泥炭藓孢子在含有化感物质的泥炭地地表水和泥炭藓沥出液中保存, 持久性显著高于在超纯水中保存。通径分析结果显示, 溶解氧是影响泥炭地泥炭藓孢子持久性的主要因子和限制因子, 养分元素氮(TN)和磷(TP)的浓度为孢子持久性的负作用因子。研究结果表明, 泥炭藓孢子散布于苔藓地被基质或淹水的丘间生境中, 比暴露于空气或在无化感物质的水中, 能更好地维持萌发力。泥炭地中, 泥炭藓孢子和其他植物的繁殖体的超长寿命可能归因于少氧、养分贫乏和丰富的化感物质等泥炭地特征性环境因子。  相似文献   

5.
研究泥炭地特征性环境因子——淹水、少氧和化感物质对泥炭藓孢子持久性的影响,可深入理解泥炭地泥炭藓持久孢子库的形成机制,为退化泥炭地泥炭藓地被恢复研究提供参考。该研究以藓丘种和丘间种两种泥炭藓的孢子为试验材料,通过室内模拟控制实验的方法,研究泥炭藓孢子在空气、超纯水、泥炭地地表水和泥炭藓沥出液中,及3种速率充气下,孢子萌发力持久性的变化。经充气处理后,泥炭藓孢子持久性显著低于不充气处理。不充气时,泥炭藓孢子在含有化感物质的泥炭地地表水和泥炭藓沥出液中保存,持久性显著高于在超纯水中保存。通径分析结果显示,溶解氧是影响泥炭地泥炭藓孢子持久性的主要因子和限制因子,养分元素氮(TN)和磷(TP)的浓度为孢子持久性的负作用因子。研究结果表明,泥炭藓孢子散布于苔藓地被基质或淹水的丘间生境中,比暴露于空气或在无化感物质的水中,能更好地维持萌发力。泥炭地中,泥炭藓孢子和其他植物的繁殖体的超长寿命可能归因于少氧、养分贫乏和丰富的化感物质等泥炭地特征性环境因子。  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.
排水严重改变泥炭地的环境和生态过程,但对泥炭藓孢子萌发力的影响尚不清楚。在长白山地区白江河泥炭地,分别在优势植物为苔藓的近原始地段和优势植物为小灌木的排水地段,钻取泥炭柱芯为试验材料,逐层测试泥炭理化指标,提取泥炭藓孢子并进行萌发试验,统计孢子数量和萌发力;经过泥炭样品年代测定,建立深度年代关系曲线,研究泥炭藓孢子萌发力对排水的响应和机制。结果表明: 整个柱芯对比,近原始地段平均孢子数略高于排水地段,两地段的平均孢子萌发力无差异,排水地段的泥炭容重、总碳和总氮都显著高于近原始地段。柱芯上部对比,排水(1987年)以后两地段孢子累积速率无显著差异,但近原始地段的平均孢子萌发力(34%)远低于排水地段(72%)。近原始地段的碳氮比与孢子萌发力呈显著正相关;排水地段的总碳、pH和埋藏时间与孢子萌发力呈显著负相关。30年前的泥炭地排水虽对孢子累积影响不大,但通过加速分解而改变了泥炭的理化性质,提升了表层泥炭中孢子萌发力,因此降低孢子库的持久性,可能导致泥炭藓在灾变性干扰后的种群持续更新潜力下降。  相似文献   

8.
泥炭藓繁殖体移植是影响泥炭地植被恢复的重要因素之一,不同移植方式的效果往往缺乏比较研究。选取长白山区白江河退化泥炭地为研究地,以自然生境的丘间种喙叶泥炭藓(Sphagnum flexuosum)和藓丘种中位泥炭藓(S.magellanicum)(后者耐旱能力较强)为实验材料,通过野外移植实验,研究水位提升与不同泥炭藓繁殖体移植方式对退化泥炭地植被恢复的影响。数据分析显示:水位条件显著影响了喙叶泥炭藓和中位泥炭藓的建植,随着水位上升,地表湿度增加,两种泥炭藓的盖度均呈明显的上升趋势;移植方式的变化短期内对泥炭藓的建植作用并不明显,但在移植2个月后,移植方式对喙叶泥炭藓表现出显著影响,即耐旱能力较强的中位泥炭藓置于上层时,喙叶泥炭藓盖度最高;水位和移植方式不存在交互作用,即在低水位条件下,中位泥炭藓置于上层的移植方式也未能提升泥炭藓的建植盖度。研究表明,水位提升是泥炭地植被恢复的十分有效的手段,因物种间存在对水分保持的差异,采用合理植物繁殖体移植方式,将会明显提升植被恢复的成效。  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.
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   

11.
Rapid, ongoing permafrost thaw of peatlands in the discontinuous permafrost zone is exposing a globally significant store of soil carbon (C) to microbial processes. Mineralization and release of this peat C to the atmosphere as greenhouse gases is a potentially important feedback to climate change. Here we investigated the effects of permafrost thaw on peat C at a peatland complex in western Canada. We collected 15 complete peat cores (between 2.7 and 4.5 m deep) along four chronosequences, from elevated permafrost peat plateaus to saturated thermokarst bogs that thawed up to 600 years ago. The peat cores were analysed for peat C storage and peat quality, as indicated by decomposition proxies (FTIR and C/N ratios) and potential decomposability using a 200-day aerobic laboratory incubation. Our results suggest net C loss following thaw, with average total peat C stocks decreasing by ~19.3 ± 7.2 kg C m−2 over <600 years (~13% loss). Average post-thaw accumulation of new peat at the surface over the same period was ~13.1 ± 2.5 kg C m−2. We estimate ~19% (±5.8%) of deep peat (>40 cm below surface) C is lost following thaw (average 26 ± 7.9 kg C m−2 over <600 years). Our FTIR analysis shows peat below the thaw transition in thermokarst bogs is slightly more decomposed than peat of a similar type and age in permafrost plateaus, but we found no significant changes to the quality or lability of deeper peat across the chronosequences. Our incubation results also showed no increase in C mineralization of deep peat across the chronosequences. While these limited changes in peat quality in deeper peat following permafrost thaw highlight uncertainty in the exact mechanisms and processes for C loss, our analysis of peat C stocks shows large C losses following permafrost thaw in peatlands in western Canada.  相似文献   

12.
吉林敦化地区全新世泥炭沉积中植硅体分析   总被引:3,自引:1,他引:2  
通过敦化吉祥泥炭沉积中的植硅体分析发现,该剖面中植硅体含量丰富,分类特征比较明显。该地泥炭中植硅体组合以示冷型植硅体占优势,温暖指数比较低,反映气候呈寒冷型,期间曾发生4次气候波动。此次研究以泥炭为信息载体,为恢复古环境、古气候演变提供了又一重要的途径。  相似文献   

13.
In this study, the possibility of using tea production waste as a new casing material in mushroom (Agaricus bisporus) cultivation was investigated. Some physical and chemical characteristics of tea waste, fermented tea waste and a mixture of tea waste with peat were compared with that of peat casing, as were their effects on yield. The highest yield was obtained from peat casing. Using tea production waste alone as a casing was not acceptable for assured yield when it was compared with peat. But, a mixture of tea production waste with peat in 1:1 (v:v) ratio increased the yield. There was no significant difference between the mushroom yields of tea production waste+peat and peat casing materials at the end of 30 and 40 days. High salt content, organic and inorganic compounds in casing materials caused reduction of yields. However, a high iron content in casing material gave a significant positive correlation with total yield at 40 days.  相似文献   

14.
Between midsummer 1976 and November 1977 some 29000 spiders belonging to 168 species were caught in pitfalls on 42 peat and upland grassland sites covering an altitude range of 11–827 m in the north of England. The similarities between the spider faunas of each site have been assessed using a modified form of Sørensen's Index and the sites clustered according to their similarities. The sites divided into two major groups; (1) mineral soils where grasses are dominant or shallow peat soils where Juncus squarrosus is dominant and (2) peat soils where Eriophorum vaginatum and Calluna vulgaris are dominant. It is suggested that this major division is the result of the plant "architecture" rather than the species composition of the vegetation. Direct comparison between paired peat and grassland sites at the same altitudes shows no marked separation in the spider species composition on the two soil types but there are differences in abundance of individual species. The three peat site clusters form an altitudinal sequence which is not the result of the decline in numbers of non-linyphiid species with increase in altitude as the cluster formation is largely dependent on the linyphiid species which dominate the catches.
Twenty one common species have been used lo identify the communities. Many of these species are often found together and form associations. Typically, a number of associations contribute to each community. Only 19 species contribute more than 4% to the numbers of individuals caught in any one community.
Diversity declines with increase in altitude, as does the number of species caught. The decline in the number of species caught is the effect of a decrease in non-linyphiid species with increasing altitude. There is no significant decline in the numbers of species of linyphiids with increase in altitude.  相似文献   

15.
Abstract. The relationship between substrate quality and pattern of revegetation of harvested peat surfaces was studied by means of a survey and a field experiment examining influences of modest NPK-fertilization on plant colonization of an initially bare peat surface. The harvested peat surfaces varied a great deal in their chemical and physical characteristics and the sites differed in revegetation pattern. Early successional vegetation was dominated by perennial species native to nutrient-poor habitats on all sites. Soluble phosphorus and ash content, mean particle size of surface peat, and thickness of peat layer had the strongest influence in a CCA-ordination of species. The species composition depended on the amount and form of soluble nitrogen in the surface peat. Sites with a high content of phosphorus and ammonium nitrogen, and with a thick peat layer were usually densely revegetated by Eriophorum vaginatum alone, while sites characterized by thin peat layers associated with a high ash content, large particle size and a high content of nitrate nitrogen were mainly dominated by different grass and weed species. Deschampsia cespitosa clearly favoured sites with a high potassium content and small particle sizes of the peat. The importance of nutrient availability for the rate and pattern of colonization was also demonstrated by the field experiment. Application of 20 g/m2 of NPK-fertilizer resulted in a significant increase in the number of established plant individuals and marked differences in species composition compared to unfertilized plots.  相似文献   

16.
Canada’s Boreal Plains peatland vegetation species assemblages are characterized by their functional ecosystem roles and feedbacks, which are important for carbon and water storage in a sub-humid climate. The vegetation communities at the peatland-upland interface, or the peatland margin ecotone, have not been extensively delineated or characterized as a distinct ecotone. Because these ecotones constitute a smouldering “hotspot” during wildfire, with carbon loss from these margins accounting for 50–90% of total peatland carbon loss, their delineation is critical. Post-fire, areas of severe peat smouldering have previously been shown to undergo shifts in vegetation community composition, resulting in a loss of key peatland ecohydrological functions. The aim of this study was to delineate Boreal Plains peatland margin ecotones and assess their prevalence across the landscape. Using split moving window analysis on vegetation transect data from a chronosequence of study sites, the margin ecotones were delineated at sites having different times since fire. No significant differences were identified in margin width over time or margin peat depths across hydrogeological settings. However, with peat depths of up to 2.46 m in small peatlands characteristic of moraine and glaciofluvial deposits, vulnerable margin peat has been demonstrated to represent a significant carbon store. Fire managers employing peatland fuel treatments for wildfire abatement and community protection should consider these confined peatlands more carefully to mitigate catastrophic carbon losses. Further, we suggest that a greater understanding is needed of the roles of peatland margin ecotones in sustaining peatland autogenic feedback mechanisms that promote paludification and recovery following wildfire.  相似文献   

17.
M. Dooley 《Plant and Soil》1970,33(1-3):145-160
Summary Fungi occurring commonly in cut-away peat were selected for autecological study, being chosen to represent both cosmopolitan and indigenous elements of the peat flora. A fungus alien to peat,Fusarium culmorum, was also included in the study. The germination in peat of the spores of these species and their ability to grow and colonise organic material added to peat were examined. It was concluded that the cosmopolitan element was composed of efficient saprophytes but that the ability of their spores to germinate in unamended peat was limited. Although Fusarium spores germinated, the germ tubes subsequently formed chlamydospores. Only spores of the indigenous peat fungi germinated well in peat but their growth habit was not suited to the colonisation and utilisation of organic matter, added to peat, in competition with the cosmopolitan flora. The concept of ‘source potential’ is introduced to explain the variance in fungal growth from different substrate bases.  相似文献   

18.
The analysis of the micromycete complexes of oligotrophic peat deposits in the Vasyugan Marsh by direct count and culture methods showed that micromycete carbon comprises no more than 3% of the total peat carbon and that the microscopic fungal biomass varies from 2 to 13 tons/hectare, depending on the season and the peat deposit thickness. Fungal spores were found in all layers of the peat deposits, whereas the mycelium was found only in the active peat layer. The high abundance of eukaryotic cells in the peats was due to the presence of yeastlike cells rather than fungal spores. Analyses by culture methods showed that micromycetes were present in all peat layers and that their abundance tended to decrease with depth, except for yeasts, which were uniformly distributed in a vertical direction. The micromycete complexes of the peat deposits were similar in their diversity and abundance of dominant species but differed in the composition of minor species. Peat yeasts were dominated by ascomycetes.  相似文献   

19.
Pristine tropical peat swamp forests (PSFs) represent a unique wetland ecosystem of distinctive hydrology which support unique biodiversity and globally significant stores of soil carbon. Yet in Indonesia and Malaysia, home to 56% of the world's tropical peatland, they are subject to considerable developmental pressures, including widespread drainage to support agricultural needs. In this article, we review the ecology behind the functioning and ecosystem services provided by PSFs, with a particular focus on hydrological processes as well as the role of the forest itself in maintaining those services. Drawing on this, we review the suitability of current policy frameworks and consider the efficacy of their implementation. We suggest that policies in Malaysia and Indonesia are often based around the narrative of oil palm and other major monocrops as drivers of prosperity and development. However, we also argue that this narrative is also being supported by a priori claims concerning the possibility of sustainability of peat swamp exploitation via drainage‐based agriculture through the adherence to best management practices. We discuss how this limits their efficacy, uptake and the political will towards enforcement. Further, we consider how both narratives (prosperity and sustainability) clearly exclude important considerations concerning the ecosystem value of tropical PSFs which are dependent on their unimpacted hydrology. Current research clearly shows that the actual debate should be focused not on how to develop drainage‐based plantations sustainably, but on whether the sustainable conversion to drainage‐based systems is possible at all.  相似文献   

20.
中国泥炭主要植物残体类型的初步研究   总被引:1,自引:0,他引:1       下载免费PDF全文
根据泥炭中植物残体组合在发生上的联系和形态上“质”的差异这一分类原则,以组成植物残体的造炭植物为依据,按植物残体组合中的优势造炭植物的生活型和造炭植物的优势种,将中国泥炭的主要植物残体组合初步划分为6个型和15个组。根据各植物残体组合型的主要特征,进行合理地开发,利用,以免浪费宝贵的泥炭资源。我国领土辽阔,自然条件复杂,沼泽类型繁多,由不同造炭植物组成的泥炭种类也十分丰富。在泥炭矿体中,造炭植物种类随着沼泽植被类型的演替而使泥炭的植物残体种类发生垂直变化,形成各种泥炭类型。因而,对泥炭植物残体的研究,既有生产实践价值,又有理论意义。  相似文献   

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