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Kinga Rudolf Tamás Morschhauser Ferenc Pál-Fám 《Central European Journal of Biology》2012,7(4):634-647
Macrofungi play an extraordinarily important role in the catalysis of the nutrient cycle of deciduous and coniferous forests. Habitat degradation adversely influences the number of fruiting bodies of macrofungi and diminishes the diversity of the fungal community. The diversity of the terricolous- and lignicolous macrofungi assemblages were compared in stands of semi-natural and two plant associations modified by humans in different degrees in North-East Hungary. We used data from 15 permanent plots that were sampled for vascular plants and macrofungi. Rank-abundance curves and Rényi’s diversity profiles were applied for diversity research. The results indicated that structure and diversity of the terricolous macrofungi assemblages were mainly influenced by climatic and habitat conditions and the degradation of the plant associations to a lesser degree. The diversity of lignicolous macrofungi was primarily affected by the continuous presence, quality, and quantity of deadwood. Accordingly, the form and degree of forest management, as well as the age of the growing stocks, influenced community structure. If nature conservation planning and conservation activity are based on those biodiversity indicators which are good proxies for macrofungi biodiversity, the latter might be optimal for preserving macrofungi biodiversity. 相似文献
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为了探讨不同类型林地中树冠层蚂蚁功能多样性的变化,本研究采用树栖蚂蚁陷阱法调查云南省绿春县天然次生林和4种人工林的树冠层蚂蚁群落,并调查了植物多样性及植物垂直密度变化。测定54种蚂蚁的头长、头宽、胸长和后足腿节长,并计算和比较了不同类型样地间的功能丰富度、功能均匀度和功能离散度的差异。结果表明:(1)不同类型林地间树冠层蚂蚁的功能丰富度指数(FRic)有显著差异,紫胶林和紫胶林-玉米混农林显著高于桉树林、天然次生林和橡胶林,同时橡胶林显著高于桉树林;不同类型林地间树冠层蚂蚁的功能均匀度指数(FEve)有显著差异,天然次生林和紫胶林显著高于桉树林。不同类型林地间树冠层蚂蚁的功能离散度指数(FDiv)有显著差异,桉树林、橡胶林和紫胶林显著高于紫胶林-玉米混农林,且橡胶林显著高于天然次生林。(2)树冠层蚂蚁功能均匀度随枯落物盖度的增加而升高;功能离散度随枯落物盖度、草本植物盖度和>300 cm处的垂直密度的增加而升高。不同林地类型中紫胶林的树冠层蚂蚁功能多样性相对较高,而这其中枯落物盖度、草本植物盖度和>300 cm处的垂直密度等环境因素起到一定积极的作用,因此对人工林进行合理的管护有利于生态系统功能的实现和保护。 相似文献
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Thaise Emilio Bruce Walker Nelson Juliana Schietti Sylvain J.‐M. Desmoulière Helder M. V. Espírito Santo Flávia R. C. Costa 《Ecography》2010,33(4):738-747
Planning of conservation priorities has often taken mapped forest types as surrogates for biological complementarity. In the Brazilian Amazon, these exercises have given equal weight to each forest type as if they were all equally distinct. Here, we examine floristic similarity between forest types to assess the reliability of vegetation maps as a surrogate for canopy tree‐community composition. We analyzed floristic differences at the genus level between twelve Amazonian forest types using 1184 one‐hectare inventories of large trees with three complementary approaches. First, we compared a map of floristic composition, from a uni‐dimensional NMDS ordination of the inventories, with a map of coarser‐level forest types commonly recognized as distinct by classification systems across Amazonia. Using Mantel and means‐difference tests, we next examined the distance‐decay of floristic similarity for all paired samples and for the pairs drawn from within and between twelve more finely divided forest types. Finally, we examined the degree of floristic separation of each pair of the twelve forest types using non‐parametric analysis of variance. Maps of floristic composition and coarse‐level forest types were highly congruent. At the finer level of classification, similarity was only slightly higher when pairs were drawn from the same versus from different forest types. This was true for all geographic distances. Nonetheless, eighty percent of the 66 paired combinations of forest types were significantly different in the unreduced genus‐space and nearly half showed little or no overlap in a two‐dimensional ordination. Three types were most distinct from all others: white sand, seasonally dry, and bamboo‐dominated forests. Here, we show that forest types exhibit variable degrees of separation. For this reason, treating all fine‐level forest types as equally distinct results in poor representation of canopy tree beta diversity. We recommend explicitly considering the degree of floristic separation between all forest types – as presented here for Amazonian flora – as a way to improve the use of this biodiversity surrogate. 相似文献
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Carlos A. López-Quintero Gerben Straatsma A. Esperanza Franco-Molano Teun Boekhout 《Biodiversity and Conservation》2012,21(9):2221-2243
Here we present the results of fungal biodiversity studies from some selected Colombian Amazon forests in relationship to plant biodiversity and successional stages after slash and burn agriculture. Macrofungal diversity was found to differ between forests occurring in two regions (Araracuara vs Amacayacu) as well as between flooded forests and terra firme forests in the Amacayacu region. Macrofungal biodiversity differed between regeneration states of different age in the Araracuara region. Suitable substrates, especially dead wood that occurred as a result of recent slash and burn agriculture, resulted in the formation of many sporocarps of wood-inhabiting species. Putative ectomycorrhizal species were found in a dipterocarp forest. Fifty two percent of the macrofungal species could not be identified to the species level, but could be assigned to a genus, and it is likely that a significant portion of these represent species new to science. Long term studies are needed to obtain a comprehensive and complete understanding of the diversity and functioning of mycobiota in Amazon forest ecosystems. 相似文献
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高寒草甸不同草地群落物种多样性与生产力关系研究 总被引:30,自引:3,他引:30
生态系统的结构和功能、生物多样性与生产力的关系问题是近年来群落生态学中研究的中心问题,其中,生态系统生产力水平是其功能的重要表现形式,用4种不同草地类型探讨自然群落的物种多样性与生产力关系.结果表明,矮嵩草草甸、小嵩草草甸和金露梅灌丛群落中物种多样性与生产力的关系呈线性增加关系,藏嵩草沼泽化草甸群落中线性增加关系不显著,这表明群落生产力除受物种多样性的影响外,也受物种本身特征和环境资源的影响.不同的环境资源和环境异质性是形成群落结构特征、物种多样性分布格局差异的主要原因之一. 相似文献
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We postulate that the biomass distribution function for an ecological population may be derived from the condition that the biomas diversity functional is maximal subject to an energetic constraint on the total biomass. This leads to a biomass distribution of the form \(p(m) = \bar m^{ - 1} \exp ( - m/\bar m)\) , where \(\bar m\) is the mean biomass per individual. The same condition yields a unique value for the biomass diversity functional. These predictions are tested against fishery data and found to be in good agreement. It is argued that the existence of a unique value for biomass diversity may provide a preliminary theoretical foundation for the observed upper limit to species diversity. 相似文献
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Diversity and ecology of wood-inhabiting aphyllophoroid basidiomycetes on fallen woody debris in various forest types in Switzerland 总被引:2,自引:0,他引:2
This study on the ecology of aphyllophoroid wood-inhabiting basidiomycetes in Switzerland showed a remarkably high species
diversity of both saprophytes and mycorrhiza-forming species. Phlebiella vaga, a saprophytic species, and Amphinema byssoides, a mycorrhizal symbiont, were the two most abundant species. A total of 3339 samples of fungal fruitbodies in 86 plots distributed
all over Switzerland belonged to 238 species. The five main biogeographical regions of Switzerland showed different pattern
of fungal species richness: while the Plateau at lower altitudes was found to be rather rich, the Northern Alps and Central
Alps, with the highest amount of forests cover, yielded less species. Although the Southern Alps exhibited the lowest species
richness, this region harbours a specific species set. These findings encourage for further studies in Central Europe, where
many species of aphyllophoroid wood-inhabiting basidiomycetes seem to be highly under-investigated. 相似文献
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甘肃小陇山林区不同生境类型蝶类多样性研究 总被引:3,自引:2,他引:3
于2006~2008年对甘肃小陇山林区不同生境类型中蝴蝶多样性进行了调查研究,研究中依据植被的不同将该林区的蝴蝶生境划分为6种类型:人工林、灌木丛和次生林、居民农田、针阔混交林、落叶阔叶林、针叶林。共获得蝴蝶标本5365只,隶属于11科116属210种。计算了6种生境类型中蝶类物种丰富度、相似性系数和多样性指数。不同生境中,灌木丛和次生林蝶类物种的多样性指数、丰富度和个体数量较高,人工林物种多样性指数、丰富度和个体数量较低;人工林与针叶林之间的相似性系数(0.4194)最高,针阔混交林与落叶阔叶林的相似性系数(0.2951)次之,人工林与灌木丛和次生林之间的相似性系数(0.0769)最低,表明各生境之间蝶类相似性系数很低。 相似文献
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SEAN L. C. O''MALLEY STEPHEN F. HUBBARD DAVE D. CHADEE 《Medical and veterinary entomology》1989,3(3):247-252
1. Oviposition of the mosquito Toxorhynchites moctezuma Dyar & Knab was investigated in four types of tropical forest in Trinidad, West Indies, using surrogate and natural ovitraps. Larvae of Tx. moctezuma are obligate predators that might be useful for the biological control of Aedes aegypti (L). 2. Significantly more oviposition occurred in seasonal-deciduous forest than in either montane or evergreen-seasonal forest. 3. Oviposition in surrogate containers (black-painted polystyrene cups, 90 mm diameter) was compared with that occurring in typical natural containers (nutpots of Lecythis zapucajo Aublet). Surrogate ovipots were relatively insensitive indicators of oviposition activity, and would be an inefficient means of harvesting Tx. moctezuma eggs. 4. Implications for the collection, culture and mass release of Tx. moctezuma are discussed. 相似文献
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Eric Sande 《Ostrich》2013,84(1-2):64-68
Sande, E. 2000. Understorey bird species diversity and abundance in three forest types of Semuliki National Park, Uganda. Ostrich 71 (1 & 2): 64–68. Semuliki National Park is a rich lowland forest in terms of biodiversity. The bird species list currently stands at 428, of which 31 species occur nowhere else in East Africa. Although the park was severely encroached for agricultural activities, all the encroachers were evicted and many species of birds still survive. A total of 61 species with 1270 individuals were trapped from all the forest types. There was no significant difference in the species diversity between the swamp, mixed and Cynometra forest types. The Little Greenbul, Yellow-whiskered Greenbul, Slender-billed Greenbul, and Olive Sunbird were significantly more abundant in the mixed forest than in the swamp forest while the arboreal insectivore frugivores, terrestrial insectivores and sallying insectivores were significantly more abundant in the Cynometra than in the swamp forest type. 相似文献
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Sullivan MB Coleman ML Quinlivan V Rosenkrantz JE Defrancesco AS Tan G Fu R Lee JA Waterbury JB Bielawski JP Chisholm SW 《Environmental microbiology》2008,10(10):2810-2823
Oceanic phages are critical components of the global ecosystem, where they play a role in microbial mortality and evolution. Our understanding of phage diversity is greatly limited by the lack of useful genetic diversity measures. Previous studies, focusing on myophages that infect the marine cyanobacterium Synechococcus, have used the coliphage T4 portal-protein-encoding homologue, gene 20 (g20), as a diversity marker. These studies revealed 10 sequence clusters, 9 oceanic and 1 freshwater, where only 3 contained cultured representatives. We sequenced g20 from 38 marine myophages isolated using a diversity of Synechococcus and Prochlorococcus hosts to see if any would fall into the clusters that lacked cultured representatives. On the contrary, all fell into the three clusters that already contained sequences from cultured phages. Further, there was no obvious relationship between host of isolation, or host range, and g20 sequence similarity. We next expanded our analyses to all available g20 sequences (769 sequences), which include PCR amplicons from wild uncultured phages, non-PCR amplified sequences identified in the Global Ocean Survey (GOS) metagenomic database, as well as sequences from cultured phages, to evaluate the relationship between g20 sequence clusters and habitat features from which the phage sequences were isolated. Even in this meta-data set, very few sequences fell into the sequence clusters without cultured representatives, suggesting that the latter are very rare, or sequencing artefacts. In contrast, sequences most similar to the culture-containing clusters, the freshwater cluster and two novel clusters, were more highly represented, with one particular culture-containing cluster representing the dominant g20 genotype in the unamplified GOS sequence data. Finally, while some g20 sequences were non-randomly distributed with respect to habitat, there were always numerous exceptions to general patterns, indicating that phage portal proteins are not good predictors of a phage's host or the habitat in which a particular phage may thrive. 相似文献
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Gerald Rosen 《Bulletin of mathematical biology》1984,46(5-6):967-969
It is observed that a dynamical continuity equation for biomass distribution yields the asymptotic steady-state exponential
dependencen=A exp(
) exhibited by certain fishery data, wherem is the biomass of an individual,n is the number of individuals per unit biomass interval, andA,
are positive constants. This dynamical approach to biomass distribution is an alternative to the global maximization principle
proposed recently by Lurié and Wagensberg. 相似文献
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生物多样性是生态学的核心问题。传统的多样性指数仅包含物种数和相对多度的信息,这类基于分类学的多样性指数并不能很好地帮助理解群落构建和生态系统功能。不同物种对群落构建和生态系统功能所起到的作用类型和贡献也不完全相同,且物种在生态过程中的作用和贡献往往与性状密切相关,因此功能多样性已经成为反映物种群落构建、干扰以及环境因素对群落影响的重要指标。同时,由于亲缘关系相近的物种往往具有相似的性状,系统发育多样性也可以作为功能多样性的一个替代。功能多样性和系统发育多样性各自具有优缺点,但二者均比分类多样性更能揭示群落和生态系统的构建、维持与功能。 相似文献
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Abstract. Sun leaves from 37 species of tree and shrub were collected in four forest types on Pulau Ubin, Singapore. Evidence of habitat-related variation in the form of leaves is presented. The species were from the habitats: mangrove, beach forest, adinandra belukar (secondary forest on degraded soils) and secondary forest on undegraded soils. The mangrove forest species sampled had thicker leaves with a lower specific leaf area than the beach forest species. Leaves of species from the adinandra belukar were thicker and smaller, with more dry weight per unit area, than those of pioneers from undegraded sites. This is interpreted as oligotrophic xeromorphy in adinandra belukar. 相似文献