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1.
长白山针阔叶混交林带花粉通量及垂直散布年际对比   总被引:1,自引:0,他引:1  
长白山针阔叶混交林一号样地2005和2006年气象塔不同高度捕捉器样品花粉分析对比表明:连续两年花粉组成都足以乔木花粉为主,但存在差异,06年乔木花粉百分比较高,灌木、草本较低,同时06年花粉通量也较高,可能与05年花期降水较多,温度较低,花粉产量低有关.连续两年花粉通量在垂直高度上具有较高的一致性,特别是主要乔木花粉类型(白蜡属、桦、栎、松属花粉).这一结果有助于更好理解表土花粉对植被的指示性,森林表土样品中的草本、低矮灌木花粉类型,应主要来自样品点附近的植物;样品中的乔木、较高灌丛花粉类型,可能来自样品点附近或更大范围植物;区域性植物对花粉组合也有一定影响.  相似文献   

2.
阴山山脉东段花粉通量及其与表土花粉比较研究   总被引:1,自引:0,他引:1  
阴山山脉东段蛮汉山和大青山山顶草甸、桦木林、虎榛子灌丛、人工油松林及杂草草原5个植被类型花粉通量与表土花粉对比研究发现,不同植被类型及同一植被类型不同样点花粉通量和花粉浓度差异明显,捕捉器样品花粉源区面积小于表土样品,能较好地反映样品点周围植被组成,但受虫媒植物和局地植物花粉影响,与表土样品花粉组合差异明显;表土样品中松属、桦属、蒿属及藜科花粉含量多高于捕捉器样品,表明这些花粉不仅易于传播,而且在表土中具有较强的保存能力;禾本科花粉具低代表性,花粉保存能力较低.地层花粉分析中应引起注意.  相似文献   

3.
选取南京丘陵地区29处样点,分别搜集表土及捕捉器样品,开展两种采样方式下孢粉组合与植被关系研究。结果表明,南京低山丘陵地区花粉类型以松属、栎属、枫杨属、榆属、蔷薇科、菊科、禾本科为主,表土花粉组合较好地反映了现代植被特征。主成分分析可以大致区分人工草坪区、农田区以及森林区的样品。农田区表土花粉浓度最低,每克仅为4 964粒,农田的翻耕以及微生物环境是造成其花粉浓度低的重要原因;森林区花粉浓度(每克29 176粒)及花粉通量(49 358粒/平方厘米/年)均很高。人类活动的增强可能会造成孢粉浓度的下降。在探究本地区历史时期人类活动时,可运用孢粉浓度以及与农作物相关的孢粉类型的变化来分析。所有捕捉器样品的乔木花粉百分比均低于其对应的表土样品,其中以松属尤为明显。  相似文献   

4.
中国草原区主要群落类型花粉组合特征   总被引:35,自引:1,他引:34  
现代表土花粉组合与植被关系研究是推断过去植被演化的基础。对中国草原区 39个样点进行植被调查及表土花粉分析的研究结果表明 ,表土花粉组合可反映出草原植被的总体特征。大多数样品中乔木花粉百分比低于 5 %。蒿属、藜科是草原区所有样品花粉组合中最主要的成分 ,两者在花粉组合中所占比例多大于 5 0 % ,且人类活动越强或气候越干旱 ,蒿属、藜科花粉所占百分比越高。花粉组合不能反映群落结构特征 ,如建群种、结构、盖度等的差异在花粉组合中表现不出来。即使以禾本科为建群种的草原群落 ,禾本科花粉所占比例也多低于 10 %。花粉浓度在草原区花粉与植被关系研究中意义不明确。典型草原与荒漠草原花粉组合存在明显区别 ,无倾向性对应分析 (DCA)分析表明 ,典型草原区样品在第一排序轴的排序值多高于 0 ,荒漠草原区样品的排序值小于 0 ;典型草原区藜科花粉百分比一般低于 2 5 % ,花粉类型多样性指数大于 2 ,当蒿藜占花粉总数的 5 0 %以上时 ,蒿藜比值大于 2。荒漠草原区藜科花粉含量多高于 2 5 % ,蒿藜比值多为 0 .5~ 2 ,花粉类型多样性指数多为 1~ 2。蒿属花粉属超代表性 ,但在蒿类建群的群落中 ,蒿属花粉多低于其在植被中的百分比  相似文献   

5.
通过对比分析北疆荒漠草原区和典型草原区表土和牛粪样品中的孢粉组合,发现这两类样品的孢粉组合大体相近,其乔木花粉百分比大都低于10%,灌木花粉平均为5.6%,草本花粉大都高于70%,并以藜科(Chenopodiaceae)、蒿属(Artemisia)为最主要的花粉类型。牛粪中孢粉种类低于表土,且乔木花粉含量(2.04%)亦低于表土(3.78%)。表土形成的时间存在一定的不确定性,而牛粪为现代样品,牛粪的孢粉组成可能会更好地指示现代植被组成,因而牛粪样品可以在北疆荒漠草原、典型草原地区作为一种新的现代孢粉研究材料。从荒漠草原到典型草原,表土中乔木花粉百分比增多,灌木和草本下降;而牛粪中则相反,乔木花粉百分比下降,灌木和草本的比例上升,这可能与牛以草本植物为主要食物有关。表土和牛粪样品中主要种属(蔷薇科、禾本科、伞形科、豆科等)与环境因子的主成分分析显示,孢粉组合与多年平均6—8月降水量和年均降水量的相关性最显著,其次为最冷月平均温度和最热月平均温度,而与年均温相关性较低。该研究结果指示,降水可能是影响北疆现代植被空间分布的最主要因素。  相似文献   

6.
在长白山北坡5个垂直植被带的林下采集29个表土(苔藓)样品进行孢粉分析,同时将其结果作对应分析.结果表明,除个别样品,在长白山垂直植被带的孢粉组合中乔木花粉占优势,其中以松属和桦木属最多,在各植被带均有分布.松属花粉最高含量出现在以红松为主的针阔混交林带的孢粉组合中;桦木属花粉则大量见于亚高山岳桦林带和以栎桦为主的阔叶落叶林带,但前者伴有耐寒、早的小灌丛杜鹃花属花粉,而在后者中则见有大量蕨类孢子.阔叶落叶林带的孢粉组合是以类型多、百分含量高的落叶乔木花粉和大量蕨类孢子为特征.亚高山针叶林带的孢粉组合中出现数量众多的云杉属花粉.在高山苔原带孢粉组合中虽然乔木花粉略占优势,但极少或不见蕨类孢子,与其他植被带比较,草本植物和小灌丛花粉明鲜较多,其中杜鹃属花粉含量在草本中占优势,其中出现苔原带的指示花粉--仙女木属.  相似文献   

7.
东北长白山垂直林带下现代表土花粉与植被关系   总被引:7,自引:0,他引:7  
在长白山北坡5个垂直植被带的林下采集29个表土(苔藓)样品进行孢粉分析,同时将其结果作对应分析。结果表明,除个别样品,在长白山垂直植被带的孢粉组合中乔木花粉占优势,其中以松属和桦木属最多,在各植被带均有分布。松属花粉最高含量出现在以红松为主的针阔混交林带的孢粉组合中;桦木属花粉则大量见于亚高山岳桦林带和以栎桦为主的阔叶落叶林带,但前者伴有耐寒、旱的小灌从杜鹃花属花粉,而在后者中则见有大量蕨类孢子。阔叶落叶林带的孢粉组合是以类型多、百分含量高的落叶乔木花粉和大量蕨类饱子为特征。亚高山针叶林带的孢粉组合中出现数量众多的云杉属花粉。在高山苔原带孢粉组合中虽然乔木花粉略占优势,但极少或不见蕨类孢子,与其他植被带比较,草本植物和小灌丛花粉明鲜较多,其中杜鹃属花粉含量在草本中占优势,其中出现苔原带的指示花粉——仙女木属。  相似文献   

8.
通过对重庆金佛山国家自然保护区10个不同植被类型的表土调查和采样,研究该区表土孢粉组合特征.结果表明,研究区植物孢粉共由106科属组成,其中以针叶乔木、蕨类和阔叶乔木孢粉占优势,含量分别为8.94%-56.30%、19.73%-46.77%和6.17%-39.28%,其次是灌木和草本花粉,分别为6.24%-29.77%...  相似文献   

9.
本文对云南泸沽湖周边山地不同植被类型下采集的32个表土样品和36个泸沽湖湖泊表层样品进行了孢粉分析,探讨了不同植被类型内的表土孢粉散布特征,对比分析了山地表土与湖泊表层孢粉分布特征的差异。结果表明,不同山地植被类型的孢粉组合具有不同的代表性成分与变化特征,能够较好地反映相应的植被类型。湖泊表层孢粉研究表明,湖泊内不同位置的孢粉组合差异较小,说明湖泊表层孢粉反映的是区域植被的平均分布状况。对比分析泸沽湖周边山地表土与湖泊表层样品的孢粉组合,两者存在一定的差异,表现为:湖泊表层的孢粉组合中乔木花粉(主要是松属)平均含量比表土高,但波动范围要小;草本花粉平均含量要低,且波动范围也小。这可能是由于乔木植物植株较高,而且有些乔木植物花粉具有气囊,更易借助风力将花粉传播到比较远的湖泊中的原因造成的。冷杉和铁杉花粉在所有样品中含量都相对较低,分别不高于6.5%和3.6%;桦属、桤木属、常绿栎类花粉的最高值出现在有这些母体植物生长的表土样品中,在其他样品中则明显较低。在表土孢粉样品中经常可以见到冷杉的气孔器,但在湖泊表层样品中却没有见到,说明气孔器不易到达湖泊中。该研究是对中国西南表层孢粉研究的有益补充,同时为泸沽湖新生代特别是第四纪化石孢粉解释提供了可靠的参考和依据。  相似文献   

10.
郝秀东  欧阳绪红  谢世友 《生态学报》2011,31(18):5235-5245
通过对重庆市南川区岩溶山区和石漠化区14个不同植被类型的表土调查和采样,以研究该区表土孢粉组合特征的差异性。结果显示:(1)岩溶山区的表土孢粉组合中以乔木花粉为优势,含量为34.38%-63.39%,其次是草本和蕨类植物的孢粉,含量为32.04%-58.18%,灌木花粉含量最小,为6.08%-29.77%,沼生草本也有少量,仅为0.14%,这与当地的现代植被基本相同;(2) 石漠化地区的表土孢粉组合以草本和蕨类植物孢粉占优势,含量为46.40%-76.47%,其次是乔木花粉(主要为马尾松),含量为17.73%-46.84%,灌木花粉含量最小,为5.79%-12.50%,说明其植被退化严重;(3)石漠化区的表土孢粉组合中有很多喜钙性、旱生性、石生性植物,对生态恢复和重建有很好的指示意义,为该区恢复和重建自然生态环境提供参考性依据。  相似文献   

11.
The collection of pollen by bees   总被引:4,自引:0,他引:4  
Bees require pollen for their reproduction and pollen comprises the basic larval food for bees. Most bees acquire pollen passively during flower visitation, but female bees may also collect pollen actively with the aid of various structural and behavioral adaptations. Most bees have evolved adaptations to concentrate pollen into discrete loads and transport pollen back to their nests. The various structural and behavioral adaptations of female bees for acquiring and transporting pollen are the basis of this review.  相似文献   

12.
燕山南部花粉散布特征   总被引:1,自引:1,他引:0  
燕山南部花9粉用布特性研究表明,空气中的花粉反映的是植物花期的季节性变化,表 粉是植物多年花粉散布的混合,冲积物花粉与空气中和表土花粉显著不同,是取样点上游表土花粉的混合,与取样点周围植被关系较小。因此,根据冲积物花粉恢复古植被,反映的是整个流域的植被面貌,而不是某一点的植被特征。  相似文献   

13.
Summary Betula pollen production and flowering, pollen transport and pollen deposition are considered for the mountain birch region of northern Finland for the ten-year period 1984–1993. The most abundant flowering year was 1989 and, after that, 1985. In these years the highest values were also recorded for pollen in the air. There is a significant correlation between the amount of pollen released and the thermal sum of the previous year. In terms of pollen deposition the peak years were 1989 and 1986. The correlation between the amount of pollen in the air and that being deposited on the ground is also statisticaly significant. It is evident that some birch pollen is already present in the air before local flowering begins and that, in some years, this non-local pollen can account for more than 20% of the yearly total. This preflowering proportion was highest in 1985 and 1993, the latter being a prolific flowering year in the south of the country. There is a clear relationship between the proportion of the non-local pollen in the air and the proportion ofBetula pubescens/pendula type pollen deposited on the ground and, conversely, there is a significant correlation between the amount of local pollen in the air and the amount ofBetula tortuosa plusB. nana type pollen being deposited on the ground. The questions both of the viability of this long-distance pollen and of its ability to cause allergic reactions are considered. An assessment is also made of the degree to which fossil birch pollen assemblages can be realistically interpreted in terms of local vegetation if a varying proportion of the same pollen type is non-local.  相似文献   

14.
Bruno Romano 《Aerobiologia》1988,4(1-2):20-26
Summary The results of six years (1982–1987) of aerobiological study in Perugia (central Italy) are reported. During this period a total of 80 different types of pollen belonging to 52 families were identified in the Perugia atmosphere. The highest percentages of pollens were found in the mid-March to mid-July period. For main taxa principal periods of pollination were identified. The outlines for the weekly issue in a newspaper of the concentration pattern of the allergenic pollens are reported.  相似文献   

15.
Summary Airborne grass-pollen concentrations in six cities in the EEC are compared, based on observations from five years, 1982–1986. Results show that there are quantitative differences both between the monitoring stations and between the years. Very provisionally, the average seasonal total of the European urban airborne grass-pollen concentration can be put at 4 to 5000 per m3 of air. Also qualitatively, regarding the seasonal fluctuations, there are differences between the stations, and between the years. Generally, the results confirm that June is the most typical grass-pollen month in northwestern Europe, whereas in mediterranean Europe May is the more prominent grass-pollen period. There seems to be little coherence between the starting dates of the grass-pollen season even at relatively nearby stations in northwestern Europe, suggestive for a great influence of the actual weather situation.  相似文献   

16.
17.
In Switzerland the concentration of allergenic pollendecreases with increasing elevation of the samplingsite of the Swiss pollen measuring network. The aim ofthis study was, to compare the pollen concentrationsof five different localities in the Swiss Alps and inthe Jura mountains, to get an idea of the differencesin the pollen abundance in altitudes above 1000 m. Theinvestigated localities are: La Chaux-de-Fonds(1040 m), Wiesen (1420 m), Davos (1600 m), Samedan(1705 m) and Gütsch (2287 m). These pollen sumswere compared to the Swiss plateau (Basel 273 m).Basel, La Chaux-de-Fonds and Wiesen show clearlyhigher pollen values than Davos, Samedan andGütsch. Pollen concentrations of Corylus,Alnus glutinosa-type and Fraxinus arereduced with increasing altitude and are only a smallproblem for allergies above 1000 m. Betulapollen are also reduced in the higher localities, butthere still occur many days with high pollenconcentrations. Especially Betula pollen frommedium range transport can play an important role forallergies in higher localities. The total grass pollensum does not decrease up to an altitude of 1500 m. Thegrass pollen concentration depends more on factorslike composition of the local grassland, land use andwind situation.Pollen concentrations at higher elevations isinfluenced by the local vegetation, a reduced pollenproduction, land use, topography, exposition, windvelocity and wind direction. These factors modify thepollen concentration considerably. Due to the complextopography of the Prealps and Alps, it is thereforenot possible to propose a general rule of pollenreduction with increasing altitude.  相似文献   

18.
本文报道在沈阳地区1965—1985年间于空气中间断收集大气花粉5年,共收花粉玻片1100张,花粉45780粒,属于24科37属或种。其中9种(或属)超过千粒,为优势种类花粉。每年沈阳市大气中花粉出现两个高峰,一个为春季(四、五月),另一个为夏秋季(七八月)。通过长期观察发现,花粉种类和数量每年虽有不同,伹差异不大,唯有豚草花粉消长明显。大气中花粉种类及数量的变化往往受到气温、国家有关绿化政策以及社会风气的影响。花粉与过敏症关系十分密切,我们采用17种花粉制成浸液为病人皮试和治疗。皮试结果阳性率最高的为蒿属花粉,其次为其它夏秋花粉,春季花粉阳性率不高,致敏性不强。用花粉浸液对过敏症者进行免疫治疗,收到一定的疗效。  相似文献   

19.
The presence or absence of starch in microspore development and in pollen grains was recorded in eleven wild tomato species (Solanum sect. Lycopersicon) and two close relatives (S. lycopersicoides and S. sitiens). In all the species starch started to accumulate in the early microspore bicellular stage and continued until the cytoplasm was filled. At flower anthesis, pollen grains were mostly starchless in the wild tomatoes, except in S. pennellii, which had starchy pollen. Starchy pollen is also present in the two related species. The latter two species had larger pollen grains and grow in drier environments than the other species. The heterogeneity of pollen starch content among all these species, supposed to have the same pollination mechanism, is a new finding supporting the idea that starch content and pollination mechanism do not necessarily influence each other. The presence of starchy pollen in the self‐incompatible species, which grow in the driest environments, raises questions regarding the relationship between carbohydrates content and pollen survival.  相似文献   

20.
The relative pollen productivity (RPP) of Pinus cembra, Larix, Picea, Gramineae, and Cyperaceae was estimated for the Upper Engadine area, an inner-alpine sub-continental valley in SE Switzerland lying above 1800 m a.s.l. The influx of pollen originating from lowlands was assumed constant between the investigated sites and could thus be used to establish relative pollen accumulation rates (rPAR) as a basis for further calculations. Wind above the canopy was assumed as the major mode of pollen transport and the effect of different wind speeds was tested. In order to evaluate the results pollen percentage values were simulated and compared with the empirical data. The method is sufficiently accurate for evaluation of spatially-explicit vegetation models, although the low number of sites eludes robust statistical testing.  相似文献   

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