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1.
大、小兴安岭植物区及交错区物种多样性比较研究 总被引:2,自引:0,他引:2
在中国东北大兴安岭植物区、小兴安岭植物区及交错区,选择典型群落,采用物种丰富度指数、Simpson指数、Shannon-Wiener指数及均匀度指数,研究了大兴安岭植物区、小兴安岭植物区及交错区物种构成和不同分布区群落的结构。分析比较了3个植物区物种多样性指数及不同生活型物种多样性指数及均匀度指数,结果表明:大、小兴安岭植物区与交错区植物种类过渡性明显,小兴安岭植物区和交错区植物群落结构以落叶松、红松、白桦针阔混交林为主,大兴安岭植物区以兴安落叶松、东北白桦、樟子松为主;大、小兴安岭植物区及交错区物种多样性指数表现为小兴安岭植物区>交错区>大兴安岭植物区;大、小兴安岭植物区及交错区不同生活型物种多样性指数变化为草本层>灌木层>乔木层,乔木层物种多样性指数差异显著,灌木层和草本层差异不显著。 相似文献
2.
Vascular flora of Mediterranean temporary pools has been studied with the aims to define its diversity and to individuate the ecological characteristics of the different plant groups associated with this relevant and endangered habitat type. Overall, 246 species were found of which 108 were terrestrial, 57 generalist of aquatic or wet habitats and 81 typical of temporary water and strongly linked to temporary pools. The results suggest that: (i) vascular flora associated with Sardinian Mediterranean temporary pools is rich and diversified; (ii) rare ferns are better represented than previously reported; (iii) plant species are generally heliophilous and acidophilous, specialized temporary pool species mainly differing from the unspecialized ones in relationship to their soil moisture requirements; (iv) these habitats are particularly important for maintaining regional freshwater biodiversity. 相似文献
3.
Aung Swe Rajesh Jeewon Stephen B. Pointing Kevin D. Hyde 《Biodiversity and Conservation》2009,18(6):1695-1714
Nematode-trapping fungi are ubiquitous in terrestrial habitats in dung, soils, litter and woody debris and they also occur in freshwater, but only one species has been found in marine habitats. The purpose of this study was therefore to investigate whether nematode-trapping fungi occurred in mangrove habitats. To achieve this we assessed the diversity of nematode-trapping fungi on decaying litter from mangroves, freshwater and terrestrial habitats (22 sites) in Hong Kong. Composite samples (n = 1,320) of decaying litter (wood and leaves) were examined and a total of 31 species of nematode-trapping fungi belonging to four genera, Arthrobotrys, Monacrosporium, and Dactylella were recorded. Twenty-nine species reported in this study are new records for Hong Kong and 16 species are new records from mangrove habitats worldwide. Nematode trapping fungi are therefore present in marine environments. Commonly encountered taxa were Arthrobotrys oligospora and Monacrosporium thaumasium which are abundant in all habitats. A. oligospora, M. thaumasium and Arthrobotrys musiformis were frequent (F > 10%). Twenty-six species were rare (0.16–9.32%). Species richness and diversity was higher in terrestrial than in freshwater and mangrove habitats (ANOVA, P < 0.001). A higher mean diversity was observed on decaying leaves as compared to decaying wood in all habitats (P < 0.001). Based on Shannon diversity index, it was also observed that taxa characterized by adhesive nets were more frequent in all habitats. This can be explained by the fact that these taxa may have a better competitive saprotrophic ability which would allow them to compete favourably in nutrient limited environments. Abiotic factors that could be linked to differences in species diversity between decaying wood and leaves are also discussed. 相似文献
4.
GO¨RAN Thor 《Biodiversity and Conservation》1997,7(1):59-72
The three major threats to lichens in Sweden; forestry, air pollution, and structural changes in the agricultural landscape, are outlined. Forestry is the most serious. The majority of the red-listed lichens in forests are found in productive forests with a continuity in tree growth, but nearly 70% of the protected area in Sweden consists of alpine landscapes. Examples of important habitats with red-listed lichens are described, e.g. Alnus glutinosa marshes, alvar-vegetation, broad-leaved deciduous forests and different Picea abies forests. The use of selected indicator species of lichens and macrofungi (mainly red-listed species) in boreal coniferous forests provides information on continuity in tree growth of an area, and on earlier influences of forestry. Examples of indicator species for different types of forest are presented and discussed. In spite of the Swedish right of common accesso, collecting of lichens is forbidden without permission from the land-owner. Collecting in protected areas is allowed only with a permit obtained from the authorities. 相似文献
5.
Rafe M. Brown Cameron D. Siler Carl. H Oliveros Luke J. Welton Ashley Rock John Swab Merlijn Van Weerd Jonah van Beijnen Edgar Jose Dominic Rodriguez Edmund Jose Arvin C. Diesmos 《ZooKeys》2013,(266):1-120
We provide the first report on the herpetological biodiversity (amphibians and reptiles) of the northern Sierra Madre Mountain Range (Cagayan and Isabela provinces), northeast Luzon Island, Philippines. New data from extensive previously unpublished surveys in the Municipalities of Gonzaga, Gattaran, Lasam, Santa Ana, and Baggao (Cagayan Province), as well as fieldwork in the Municipalities of Cabagan, San Mariano, and Palanan (Isabela Province), combined with all available historical museum records, suggest this region is quite diverse. Our new data indicate that at least 101 species are present (29 amphibians, 30 lizards, 35 snakes, two freshwater turtles, three marine turtles, and two crocodilians) and now represented with well-documented records and/or voucher specimens, confirmed in institutional biodiversity repositories. A high percentage of Philippine endemic species constitute the local fauna (approximately 70%). The results of this and other recent studies signify that the herpetological diversity of the northern Philippines is far more diverse than previously imagined. Thirty-eight percent of our recorded species are associated with unresolved taxonomic issues (suspected new species or species complexes in need of taxonomic partitioning). This suggests that despite past and present efforts to comprehensively characterize the fauna, the herpetological biodiversity of the northern Philippines is still substantially underestimated and warranting of further study. 相似文献
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7.
Marilen M. Parungao Sally C. Fryar Kevin D. Hyde 《Biodiversity and Conservation》2002,11(7):1185-1194
Ten leaves from each of 13 different tree types from two differentrainforest sites in North Queensland, Australia were examined in order toestablish the fungal diversity developing on these leaves. A total of 57microfungi were identified, most of which were mitosporic fungi. Speciesdiversity in terms of richness and evenness were compared and the Mt Lewis sitewas found to be richer as compared to the Butchers Creek site. Statisticalmeasurements of diversity indices, however, showed that the two forest siteswere of similar diversity. Thirty-six of the fungi identified occurred only onone leaf type, indicating possible host specificities or recurrences. The samplesize, however, is deemed to be insufficient, as a larger sample size may haveresulted in less of the fungi appearing to be host specific. It is recommendedthat future studies should include more leaf samples and less tree types. It isparticularly important that the same leaf species are collected within the samesite and at different sites in order to establish the effects of host on fungalcomposition. 相似文献
8.
The Effect of Dew and Fog on Lithic Lichens Along an Altitudinal Gradient in the Negev Desert 总被引:1,自引:0,他引:1
The negative effect of high levels of heavy metals on the activity of soil microorganisms is well-known. However, some microorganisms survive even in high levels of heavy metals, and the microbial activity can therefore, help to recover these polluted soils. Microbial metal uptake in contaminated soils has to be tightly regulated to avoid toxic effects for the cells. These mechanisms of metal resistance are frequently associated to transport-related membrane proteins that mediate bacterium's direct metabolic interactions with the complex soil and aquatic harsh environments. This study reports the identification of gene clusters in rhizobial strains that are regulated by heavy metals, particularly chromium. A DNA fragment was amplified from R. leguminosarum, and in silico analysis of the sequence obtained revealed a putative protein homologue to a cation/multidrug efflux pump component (GenBank DQ398937). Another amplified DNA fragment, with 960 bp, has strong homology with anion ABC transporters (GenBank ZP_002212691) and a peptide ABC transporter (GenBank NP_766950), was identified in Mesorhizobium loti (GenBank DQ398941) and Sinorhizobium meliloti. Using Chromosome Walking technique, a single product from Sinorhizobium meliloti was cloned and sequenced. This new fragment enlarged more 302 bp to the initial sequence corresponding to the ABC transporter, confirming homology with an ATPase from PP superfamily (GenBank ZP_00197146.1). 相似文献
9.
Manganese oxyhydroxides have been found deposited on the surface of the lichen Catillaria chalybeia on an altered rhodochrosite. It is suggested that the Mn was mobilised from the ore surface via surface-weathering and redeposited in the thallus. The lichen Acarospora smaragdula also grew upon the ore but showed no sign of Mn deposition. Nine further lichens and two bryophytes were also found on the ore. 相似文献
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Biodiversity conservation in Changbai Mountain Biosphere Reserve, northeastern China: status, problem, and strategy 总被引:2,自引:0,他引:2
The Changbai Mountain Biosphere Reserve (CMBR) is the largest and one of the earliest natural reserves established in China. The continuous losses of species and ecosystems in the reserve since its establishment have raised numerous concerns within China and beyond, which also leads some people to question the function and efficiency of natural reserves in protecting biological and ecological resources. By collecting the published data, conducting field investigation, and interviewing local people, we present the current status of biological and ecological diversity/resources in the reserve and analyze the major factors causing biodiversity loss in the reserve in an ecological and socio-economic context. We found that the high human population pressure, mismanagement practices of resources, a poor resource evaluation system which underestimates the ecological value of the natural reserve, an inappropriate economic development policy, and rapid expansion of the tourist industry were the major causes leading to the biodiversity loss in the reserve in the past few decades. In order to manage the biological resources and biodiversity in the CMBR in a sustainable way, we recommend some strategies and measures which include balancing economic development and biological/ecological conservation, controlling human population in the reserve, encouraging collaboration within and outside the reserve, especially the areas around the reserve, enhancing governmental assistance and subsidy to the local residents, and promoting scientific research and biodiversity education in the local communities. 相似文献
12.
Eighteen species of eleven lichen genera were found on driftwood and worked timber deposited on the beaches in the Hornsund
and Billefjorden regions (the west coast of Spitsbergen, Svalbard archipelago). Majority of them indicate low substrate specificity
in the high arctic regions. Only three species (Caloplaca spitsbergensis, Lecanora mughicola, L. orae-frigidae) are typical for lignum. Most of the taxa are widespread in Svalbard. Species like: Caloplaca holocarpa, C. spitsbergensis, Protothelenella sphinctrinoidella, Rinodina archaea were sporadically reported till now. Lecanora mughicola was not reported from Svalbard up to the present and this is the first record of the species for the region. 相似文献
13.
通过对采自山东昆嵛山的4000余号苔藓植物标本进行鉴定,发现昆嵛山分布有苔藓植物56科131属318种,包括山东新记录种69种。在昆嵛山的苔藓植物中,苔类植物有22科28属41种,藓类植物有34科103属277种。昆嵛山苔藓植物区系主要由青藓科(45种)、真藓科(33种)、丛藓科(31种)、灰藓科(24种)、绢藓科(18种)、曲尾藓科(15种)等一些大科组成。单种属和寡种属数量较多,但特有现象不明显。土生和石生群落优势明显,水生和树生群落缺乏。区系地理成分复杂,分布类型多样,温带成分优势明显,但也具有一定的热带成分。本研究旨在进一步促进山东苔藓植物研究,并与现代苔藓植物学的发展接轨,也为中国苔藓植物的研究提供新的资料。 相似文献
14.
紫金山次生林林窗植被和环境的研究 总被引:43,自引:5,他引:43
研究了紫金山次生林林窗的形成、分布、植被及环境特征 .林窗主要由人为砍伐马尾松形成 ,呈随机分布 .林窗内共出现木本植物 53种 ,频度最高者为枫香 ,频度 1 0 0 % ,其次为刺楸、白栎、黄连木和栓皮栎 .共出现 1 2 83个体 ,其中枫香占 1 8.7% ,黄檀 1 0 .9% ,白栎 8.7% ,刺楸、栓皮栎分别为 5.5%和 5.3% .林窗的种类密度和个体密度分别为 7种和 1 90株·1 0 0m- 2 .方差分析表明 ,枫香、黄檀、白栎和栓皮栎在林窗内的密度分布与随机分布预测值有显著差异 ,反映其分布的非随机性 .林窗内 ,基周 <2cm的个体占 59.0 % ,树龄愈高 ,个体数愈少 ,基周 4cm时 ,个体数下降 70 .5% ,1 0cm时下降 96.2 % .林窗内光照强度、大气温度、大气湿度及土壤元素分布 ,在时序上有近似与旷地的规律性 ,空间上则显现更复杂的格局 . 相似文献
15.
Diversity and ecological distribution of macrofungi in the Laojun Mountain region,southwestern China
Ying Zhang De Qun Zhou Qi Zhao Tong Xin Zhou Kevin D. Hyde 《Biodiversity and Conservation》2010,19(12):3545-3563
Surveys of the macrofungi associated with eight different vegetation types in the Laojun Mountain region of southwestern China
yielded approximately 520 species belonging to 175 genera. Species richness and diversity were highest in mixed conifer and
broadleaf forests and deciduous broadleaf forests. In typical forests of temperate regions of the world, there are five dominant
genera of ectomycorrhizal macrofungi. The distribution patterns of species in these genera for the different vegetation types
indicate that they are able to associate with a wide variety of different trees. Analysis of data for common macrofungal species
and taxonomic similarity of the communities present in the eight vegetation types suggest that the greater the differences
in the plant species that comprise the vegetation, the less similar are the common macrofungal species associated with the
most common host plants. These same data also show that some species of macrofungi occur only in one or two vegetation types.
There were 156 species of edible fungi recorded from the different vegetation types, and these fungi appear to be abundant
in the Laojun Mountain region. At different positions along the elevation gradient, positive correlations existed with respect
to the relationship between species richness and diversity, and the general trend was for macrofungal species richness and
diversity to decrease with increasing elevation, with the numbers of species recorded being significantly lower at the very
highest elevation. The relative dominance of certain taxa in the assemblage of species present was found to increase with
increasing elevation, and variation in the evenness component of diversity was slight. As such, the differences in dominance
and evenness were also not significant (P > 0.05). Macrofungal species richness was slightly more diverse on shaded slopes than on more exposed (sunny) slopes, and
the differences in species diversity, dominance and evenness were relatively minor. This suggests that slope aspect may only
weakly influence the distribution of macrofungal species in the Laojun Mountain region. 相似文献
16.
Tree species diversity, biovolume and forest stand structure were investigated in natural forest ecosystem located around
some selected communities in the bitumen-producing area of Ondo state, Nigeria. Two forest reserves and four free areas distributed
in 4 Local Government Areas (LGA) of the state were selected for data collection, out of the total 6 LGAs in the bitumen belt
of the state. The two forest reserves are Oluwa FR at Legge in Odigbo LGA and Eba Island FR in Ese-Odo LGA while the four
free areas are located close to each of Omotoso community (Odigbo LGA), Ode-Aye community (Okitipupa), Igbo-Egunrin community
(Ilaje) and Igbotako community (Okitipupa). Eight plots of equal size (20 × 20 m) were located in each of the selected location,
using systematic line transect sampling design. In each plot, all living trees with dbh ≥ 10 cm were identified with their
botanical names and their dbhs were also measured. The results of the study reveal that there were ninety nine (99) tropical
hardwood timber species (range: 21 to 48 species per selected forest). These species were distributed among twenty nine (29)
families. While Funtumia elastica has the highest population distribution across the selected communities’ forest, Euphorbiaceae was the dominant family in
the entire area. Although there was a moderate variation in the biodiversity indices among the selected communities’ forest,
the Shannon-Weiner diversity index of H1 = 4.02 and species evenness of E = 0.88 were obtained for the entire study area. Tree density summing up to 2,740 trees/6 ha
varied moderately, with a range of 361–609 tree/ha, among the communities. Though most of the trees encountered belonged to
the lowest diameter size class, the mean basal area and biovolume were 26.69 m2/ha and 262.36 m3/ha respectively. Recommendations guiding the decision on the allocation of the communities’ forest to the bitumen exploratory
industries are made and the need for good forest management of the prospective area of bitumen exploration of Ondo state is
emphasized. This is to prevent the imminent loss of biological diversity that would eventually accompany the exploration. 相似文献
17.
Fire in tropical dry forests: corticolous lichens as indicators of recent ecological changes in Thailand 总被引:1,自引:0,他引:1
The distribution of lichens in lowland deciduous and evergreen forests in Thailand is used to interpret recent changes in the distribution of these forests. The role of fire in changing the forest structure, microclimate and species content is discussed. Characteristic corticolous lichen communities of dry deciduous and moist evergreen forests are described, as well as changes in the composition of the flora following fire events. Where frequent fires have altered the forest rates of change in forest type are suggested using lichen data from randomly selected trees in forest plots, and growth rates of sampled species in quadrats. The disjunct nature of the lichen floras in lowland deciduous and evergreen forests is discussed, their origin and use in interpreting changes in forest types in monsoon climates over long periods of time. 相似文献
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Xikuangshan is located in Lengshuijiang City, Hunan province, China. With intensive mining and metallurgical activities, large amounts of tailing containing heavy metals (in this study, the term “heavy metals” is used for both metals and metalloids) were introduced to the soils around the mine area. Those heavy metals including antimony and other heavy metals would pose huge risk to human health and ecological environment. With a view to providing information on the extent of contamination and potential ecological risk of heavy metals in the soils of this mine area, the total contents of antimony (Sb), manganese (Mn), zinc (Zn), arsenic (As), cadmium (Cd), and lead (Pb) in the soils were examined. The results revealed that the predominant pollutants in this area were Sb, Cd, and Zn with mean concentrations being 356.58, 9.98, and 486.42 mg kg?1, 119.66, 117.41, and 5.17 times of the corresponding background values respectively. The pollution indices (Ps) indicated that the pollution levels of all sampling zones were serious including the control zones. The ecological risk levels of all heavy metals were very high on all the sampling zones except sampling zone 7 (as considerable), and Sb, Cd, and As were regarded as making great contribution to the risk indices (RI). 相似文献
20.
山东五莲山植物群落结构及物种多样性 总被引:3,自引:0,他引:3
五莲山自然保护区地处鲁东南沿海地区,为全面了解其群落结构组成及物种多样性,作者进行了野外调查,共获得11个标准样方,面积6 600 m2。样方内记录到高等植物52科141种。该保护区地带性植被为常绿—落叶针阔叶天然次生混交林、落叶阔叶林,主要森林植被为赤松—板栗群落(Pinus densiflora-Castanea mollissima community)、麻栎—赤松群落(Quercus acutissima-Pinus densiflora community)、赤松—杜鹃群落(P. densiflora-Rhododendron simsii community)、麻栎—杜鹃群落(Q. acutissima-Rhododendron simsii community)。样方数据显示该区域木本植物种类不是很丰富,但植物群落结构复杂,具有明显的生境异质性,其多样性指数乔木层<木本层<灌木层。作者认为影响该保护区核心区多样性的最显著特征应该为海拔和坡度,而人为干扰会严重影响外围保护区植被类型及其物种多样性。整体上看,本区域正处于群落演替早期,种间竞争尚不充分,物种多样性偏低。 相似文献