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1.
This study reports, for the first time, the investigation of the distribution of Korean saxicolous lichens in the coastal rocks of U-do islet, which is known as an unpolluted zone in Jeju. More than thirty lichens were obtained and investigated from the coastal rocks frequently contacted by seawater. A molecular analysis using PCR amplification of the rRNA ITS regions revealed the coastal rock lichens could be placed into 8 families and 14 genera, Ramalinaceae (Bacidia, Ramalina), Physciaceae (Buellia, Dirinaria, Phaeophyscia, Physcia, Pyxine), Lecanoraceae (Candelaria, Lecanora), Parmeliaceae (Xanthoparmelia), Graphidaceae (Graphis), Pertusariaceae (Pertusaria), Rhizocarpaceae (Rhizocarpon), and Teloschistaceae (Caloplaca), showing a diversity of lichens, with foliose (flat leaf-like), crustose (crust-like), and fruticose (miniature shrub-like) life forms might be distributed in the coastal rocks. These findings suggested the possibility that the lichens identified in the present work might be resistant to a salty environment.  相似文献   

2.
Dung beetles (Scarabaeinae) are conspicuous components in most terrestrial ecosystems, performing important ecological functions and services. Being sensitive to several types of disturbance, they have been successfully used as indicators of habitat change. Dung beetle communities in tropical rainforests have been well studied, but considerably less information is available for tropical dry forests. In this study I sampled dung beetles in two undisturbed habitats, deciduous forest and semideciduous forest, and two disturbed habitats, secondary forest and open area habitat, in the Chamela-Cuixmala region of western Mexico. Dung beetle species with high indicator value for each habitat were identified. Beetle abundance, observed species richness and estimated species richness were similar in the three forest habitats, but significantly lower in the open area habitat. A more detailed analysis of species-specific abundances in the three forest habitats revealed some differences. Transects of one of the undisturbed habitats, the deciduous forest, were more similar to the non-adjacent transects of disturbed secondary forest, than to the adjacent undisturbed semideciduous forest transects. Unlike studies in other tropical sites that have found a decrease in equitability in Scarabaeinae assemblages between undisturbed forest and disturbed habitat (particularly open habitats), in the Chamela-Cuixmala region all four habitats showed similar low equitability in community structure, with two or three very dominant species.  相似文献   

3.
Hua Zhu  Min Cao  Huabin Hu 《Biotropica》2006,38(3):310-317
Xishuangbanna of southern Yunnan is biogeographically located at a transitional zone from tropical Southeast (SE) Asia to subtropical East Asia, and is at the junction of the Indian and Burmese plates of Gondwana and the Eurasian plate of Laurasia. The flora of the region consists of a recorded 3336 native seed plant species, belonging to 1140 genera in 197 families, among which 83.5 percent are tropical genera and 32.8 percent are endemic to tropical Asia, suggesting a strong affinity to tropical Asian flora. The vegetation of Xishuangbanna is organized into four forest types: tropical rain forest, tropical seasonal moist forest, tropical montane evergreen broad‐leaved forest, and tropical monsoon forest. The tropical rain forest in Xishuangbanna has the same floristic composition of families and genera as some lowland equatorial rain forests in SE Asia, and is dominated (with a few exceptions) by the same families both in species richness and stem dominance. The exceptions include some deciduous trees in the canopy layer, fewer megaphanerophytes and epiphytes, and a higher abundance of lianas and microphyllic plants. We consider the tropical rain forest of Xishuangbanna as a type of tropical Asian rain forest, based on their conspicuous similarities in ecological and floristic characteristics.  相似文献   

4.
西双版纳热带森林地区不同生境蜜蜂的物种多样性研究   总被引:9,自引:0,他引:9  
本文研究了西双版纳热带森林地区不同生境蜜蜂的物种多样性。共鉴定蜜蜂总科5科、22属、77种。8个生境的物种丰富度指数DMA的取值范围在1.914~7.877之间,多样性指数H′的范围是0.608~1.398,均匀度指数Jsw为0.716~0.956,其中保护区、雨林和灌丛拥有较高的物种丰富度指数和多样性指数,橡胶林的最小,而均匀度指数以曼养广龙山最大,农田最小。根据不同生境物种的相似性系数C进行系统聚类,8个生境在相似性系数0.169的水平时全部聚合在一起。傣族龙山在保持雨林的蜜蜂物种多样性中可以起一定的作用,但很有限,且当龙山面积越小,受人为干扰越严重时,物种多样性的损失就越大。雨林一旦被开垦为橡胶林或农田,雨林中原有的许多蜜蜂将会消失,物种多样性显著减少。  相似文献   

5.
云南热带雨林具有与东南亚低地热带雨林类似的群落结构、生态外貌特征和物种多样性,是亚洲热带雨林的一个类型。它的植物区系组成中有90%的属和多于80%的种为热带分布成分,其中约40%的属和70%的种为热带亚洲分布型,它含属种较多的优势科和在群落中重要值较大的科也与亚洲热带雨林相似,是亚洲热带雨林和植物区系的热带北缘类型。云南西南部、南部与东南部的热带雨林在群落结构和生态外貌上类似,但在南部与东南部之间有明显的植物区系分异,它们经历了不同的起源背景和演化历程。云南的热带雨林在很大程度上由西南季风维持。喜马拉雅隆升导致西南季风气候形成和加强,在云南热带局部地区产生了湿润气候,发育了热带雨林植被。现在的云南热带雨林里或其分布地区有落叶物种或热带落叶林存在,这不仅是季节性气候的影响,推测在晚第三纪或第四纪更新世云南热带地区曾经历了干旱气候。云南热带雨林的分布主要受制于局部生境,并非地区性气候条件。  相似文献   

6.
According to the Convention on Biological Diversity (CBD) the development of bioindicators is extremely necessary to achieve the conservation targets by 2010, and insects are considered an effective group for this goal. Drosophilids are regarded as potential indicators, although this idea remains untested. Therefore, we followed up a protocol to test the drosophilid potential indicator for human disturbance in the Brazilian Savanna, one of the richest and most threatened tropical biomes in the world. Sampling was undertaken in one urban environment and two biological reserves, representing four habitat types (undisturbed gallery forest, disturbed gallery forest, undisturbed savanna, and urban environment). We examined differences in the drosophilid assemblages among habitat types and used the Indicator Value (IndVal) method to point out the indicator species. We also tested the two-stage indicator validation, a protocol recently proposed in the literature, to validate the indicator species for undisturbed gallery forest and savannas, in independent samples. The assemblage variables varied mainly in undisturbed gallery forests, and reflected changes from an undisturbed to a disturbed stage. The IndVal associated with the two-stage protocol showed reliable characteristic species, which are very helpful for diagnostic surveys. Likewise, species that can detect changes in the habitats were also found. We found a set of indicators, which together may be very efficient for both assessing and reflecting a variety of conditions, improving the confidence of the bioindication system, expanding the taxonomic options for bioindicators, and therefore, contributing to the conservation of this region.  相似文献   

7.
Abstract. Ecological and biogeographic analyses of the tropical rain forest in south Yunnan were made using data from seventeen sample plots and floristic inventories of about 1000 species of seed plants. The rain forest is shown to be a type of true tropical rain forest because it has almost the same profile, physiognomic characteristics, species richness per unit area, numbers of individuals in each tree species and diameter classes of trees as classic lowland tropical rain forests. As the area is at the northern margin of monsoonal tropics, the rain forest differs from equatorial lowland rain forests in having some deciduous trees in the canopy layer, fewer megaphanaerophytes and epiphytes but more species of lianas as well as more species of microphylls. In its floristic composition, about 80% of total families. 94% of total genera and more than 90% of total species are tropical, of which about 38% of genera and 74% of species are tropical Asian. Furthermore, the rain forest has not only almost the same families and genera, but also the same families rank in the top ten both in species richness and in dominance of stems, as lowland forests in southeast Asia. It is indisputable that the flora of the rain forest is part of the tropical Asian flora. However, most of the tropical families and genera have their northern limits in south Yunnan and most have their centre of species diversity in Malesia. More strictly tropical families and genera have relatively lower species richness and importance compared with lowland rain forests in tropical southeast Asia. Thus, the flora also shows characteristics of being at the margin of the tropics. Based mainly on physiognomy and floristic composition the tropical rain forest of Yunnan is classified into two types, i.e. seasonal rain forest and wet seasonal rain forest, the latter is further divided into two subtypes, i.e. mixed rain forest and dipterocarp rain forest. From analysis of geographic elements it is also shown that the tropical rain forest of Yunnan occurs at a geographical nexus with its flora coming mainly from four sources, i.e. Malesia, south Himalayas, Indochina and China.  相似文献   

8.
Species diversity of vascular epiphyte plant communities was studied in La Carbonera, a montane rain forest dominated by Podocarpaceae in the Venezuelan Andes. We compared the epiphyte communities of the primary, disturbed, and secondary forest areas of La Carbonera in order to augment the scarce knowledge on the effects of anthropogenic disturbance on these important elements of tropical vegetation. Diversity of vascular epiphytes (191 species in the whole forest area) was low in the disturbed and secondary areas (81 spp.) compared to adjacent primary forest (178 spp.). Four types of disturbed forest and secondary vegetation supported different numbers of epiphyte species, showing a decline with increasing degrees of disturbance (65 spp. along a road transect, 42 spp. on relict trees in disturbed forest, 13 spp. in a tree plantation and 7 spp. in a former clearing, both secondary vegetation units). Epiphytic species composition in primary and disturbed or secondary forest areas differed markedly: disturbed habitats harboured fewer fern and orchid species but more bromeliad species than the primary forest. Probably the families occurring only in primary forest sites of our study may be useful as bioindicators to determine the degree of disturbance in other habitats of mountain rain forests as well. Epiphyte abundance was also lower in disturbed habitats: a remnant emergent tree supported only about half as many epiphyte individuals as a member of the same species of similar size in the primary forest. The decrease in species numbers and abundance as well as the differences in species composition are mainly due to the less diverse phorophyte structure and less differentiated microclimate in the disturbed and secondary vegetation compared to the primary forest.  相似文献   

9.
Lichens have value as bioindicators of environmental pollution, climate change, and ecological continuity. Extensive work has been undertaken in temperate areas, but in only few cases have the techniques been applied in the tropics. Most tropical studies to date are in relation to air pollution and forest disturbance, but these are scattered geographically and remain to be undertaken in most tropical regions. The potential of lichens as rapid bioindicators in the tropics can start to be realized even where the species described are not fully identified as they are perennial and separable by eye or hand lens, and a lack of training is identified as the main constraint. An extensive bibliography is included.  相似文献   

10.
Anthropogenic landscape changes and avian diversity at Los Tuxtlas, Mexico   总被引:7,自引:7,他引:0  
Faced with rapid and extensive conversion of tropical rain forests to a landscape consisting of pasture lands, and with the need to preserve the avian diversity of tropical regions, it is imperative to determine how different species have responded to anthropogenic alterations of their natural habitats. We sampled birds in undisturbed and disturbed forest islands in regenerating forests and in four replicates of each of the following man-made habitats: arboreal agricultural habitats (cacao, coffee, mixed, citrus and allspice), non-arboreal agricultural habitats (corn, jalapen~o chili pepper and bananas), live fences and pastures, at Los Tuxtlas, Veracruz, Mexico. We censused 22145 birds representing 226 species. We detected 79% of the species in forest habitats, 80% in agricultural habitats, 43% in live fences and only 5% in pastures. Isolating distance and continued disturbance by humans of forest fragments were important variables influencing species' richness. Arboreal agricultural habitats and live fences were richer in species and in birds than non-arboreal man-made habitats. Economic surveys showed that some of the crops investigated yield higher returns than cattle ranching based on pastures. We discuss the conservation value for birds of agricultural islands and of live fences as landscape elements that help reduce physical and biotic isolation among remaining configurations of forest fragments in Los Tuxtlas.  相似文献   

11.
We studied the ecological distribution of pteridophytes (ferns and fern allies) along eight 8-km transects covering 12.7 ha in Peruvian Amazonia. Subunits of 200 m2 of the transects have previously been classified into four different forest types, and here we document and quantify the floristic differences among these forest types. Pteridophytes have been suggested as an indicator group to classify rain forest habitats, but this requires that the ecological preferences of the species are well documented and consistent across geographic regions. Here we analyzed in detail the distribution and diversity patterns of 130 species across the four rain forest types. Relative species abundance and species diversity were similar among some of the forest types and differed among others, but the species composition differed markedly. Our results largely confirmed the earlier interpretation of the edaphic preferences of the pteridophyte species in western Amazonia. This supports the proposition that deterministic processes have an important role in influencing the floristic composition of Amazonian forests.  相似文献   

12.
We studied temporal and spatial dynamics of extremely diverse moth ensembles (Lepidoptera: Pyraloidea) along a gradient of forest disturbance ranging from undisturbed primary tropical rain forest to different kinds of modified forest and open cultivated land at the margin of Mount Kinabalu National Park (Sabah, East Malaysia). We sampled moths by light trapping during two periods (March‐May and August‐September 1997). We collected a total of 7724 individuals representing 680 species during 78 light‐trapping nights at six study sites. Species diversity (Fisher's α) of ensembles in undisturbed primary forest was distinctly higher than in disturbed or secondary forest. More pyraloid moths were attracted in undisturbed primary forest. Samples from disturbed primary or old‐growth secondary forest were statistically indistinguishable from the undisturbed primary forest ensemble in regard to species composition. Thus, pyraloid ensembles from disturbed forest with tall trees remaining appeared to represent impoverished subsets of the undisturbed primary forest community. The more heavily disturbed sites had a distinct fauna and showed a stronger faunal differentiation among each other. Four species of the genus Eoophyla, in which aquatic larvae feed on algae in fast‐running streams benefited prominently from forest disturbance. Temporal variation of ensembles was remarkably concordant across the disturbance gradient. Relative abundance variation of the commonest species was identical at all sites. Overall, pyraloid moths responded more sensitively to anthropogenic habitat alteration than most other moth taxa studied thus far in tropical regions and allowed for an analysis of diversity patterns at a high temporal resolution.  相似文献   

13.
Understanding the ecological interactions between plant reproductive strategies and frugivore feeding behavior can offer insight into the maintenance of tropical forest biodiversity. We examined the role of plant ecological and phenological characteristics in influencing fruit consumption by the White‐bearded gibbon (Hylobates albibarbis) in Gunung Palung National Park, Indonesian Borneo. Gibbons are widespread across Borneo, highly frugivorous and perform important seed dispersal services. We compare multiple models using information criteria to identify the ecological and phenological predictors that most strongly influence gibbon fruit use of 154 plant genera. The most important predictors of resource use were the overall abundance of a genus and the consistency of fruit availability. Plant genera can maintain constant fruit availability as a result of (1) individual stems fruiting often or (2) stems fruiting out of synchrony with each other (asynchrony). Our results demonstrate that gibbons prefer to feed on plant genera that provide consistent fruit availability due to fruiting asynchrony. Because gibbons feed more often on genera that fruit asynchronously, gibbons are more likely to disperse seeds of plant genera with this reproductive strategy. Research on other frugivorous species is needed to determine whether the results for gibbons are generalizable more broadly. Finally, these results suggest that asynchronously fruiting plant genera may be particularly important for habitat restoration in tropical forests designed for frugivore conservation.  相似文献   

14.
论滇南西双版纳的森林植被分类   总被引:3,自引:0,他引:3  
朱华 《云南植物研究》2007,29(4):377-387
本文基于多年研究成果的总结,对西双版纳森林植被的分类、主要植被类型及其特征进行了系统归纳,并讨论了它们与世界类似热带森林植被的关系。以群落的生态外貌与结构、种类组成和生境特征相结合作为植被分类的原则和依据,可以将西双版纳的热带森林植被分类为热带雨林、热带季节性湿润林、热带季雨林和热带山地常绿阔叶林四个主要的植被型,包括有至少二十个群系。热带雨林包括热带季节雨林和热带山地(低山)雨林二个植被亚型。热带季节雨林具有与赤道低地热带雨林几乎一样的群落结构和生态外貌特征,是亚洲热带雨林的一个类型,但由于发生在季风热带北缘纬度和海拔的极限条件下,受到季节性干旱和热量不足的影响,在其林冠层中有一定比例的落叶树种存在,大高位芽植物和附生植物较逊色而藤本植物和在叶级谱上的小叶型植物更丰富,这些特征又有别于赤道低地的热带雨林。热带山地雨林是热带雨林的山地亚型,是该地区热带山地较湿润生境的一种森林类型,它在植物区系组成和生态外貌特征上类似于热带亚洲的低山雨林,隶属于广义热带雨林植被型下的低山雨林亚型。热带季节性湿润林分布在石灰岩山坡中、上部,在群落外貌上类似热带山地常绿阔叶林但在植物区系组成上与后者不同,它是石灰岩山地垂直带上的一种植被类型。热带季雨林是分布在该地区开阔河谷盆地及河岸受季风影响强烈的生境的一种热带落叶森林,是介于热带雨林与萨王纳之间的植被类型。热带山地常绿阔叶林(季风常绿阔叶林)是西双版纳的主要山地植被类型,它分布在热带季节雨林带之上偏干的山地生境。它在植物区系组成上不同于该地区的热带季节雨林,在生态外貌特征上亦不同于热带山地雨林,是发育在受地区性季风气候强烈影响的热带山地的一种森林植被类型。  相似文献   

15.
瑞丽莫里热带雨林种子植物区系的初步研究   总被引:1,自引:0,他引:1  
朱华  赵见明  李黎  司洪虎   《广西植物》2006,26(4):400-405
初步分析了鲜为人知的滇西南瑞丽莫里的热带雨林植物区系组成与地理成分。该植物区系中热带和主产热带的科占总科数的80%以上,热带分布属占总属数的84.1%;典型热带分布种占总种数的82.1%,该区系在科、属和种水平上均以热带成分占优势,明显属于热带性质的植物区系。在其热带分布属中,又以热带亚洲分布属最多,占总属数的26.5%;典型热带分布种中也以热带亚洲分布及其变型的种占绝对优势,占总种数的72.9%,反映了该植物区系具有热带亚洲植物区系的性质特点。在其热带亚洲成分中,又具体以南亚—大陆东南亚成分比例最高,反映了滇西南的热带雨林植物区系由于地域邻接关系,受印度(喜马拉雅)—缅甸植物区系的强烈影响。  相似文献   

16.
A total of 2277 species of vascular plant in 868 genera and 158 families are recorded as native to the Republic of Singapore. This flora consists of 174 pteridophytes (7.6% of the total), eight gymnosperms (0.4%), 590 monocots (25.9%) and 1505 dicots (66.1%).Median values of species per family, genera per family and species per genus are 5, 2 and 1, respectively. The most abundant 'families' and genera in terms of species are Orchidaceae (196 spp.), Pteridophyta (174 spp.), Rubiaceae (140 spp.), Euphorbiaceae (116 spp.), Gramineae (100 spp.) and Eugenia (46 spp.), Ficus (43 spp.), Dendrobium (33 spp.), Bulbophyllum (29 spp.) and Cyperus (29 spp.). Trees constitute 37.2% of the flora, shrubs 9.8%, herbs 25.9%, climbers 14.0% and epiphytes 13%.Euphorbiaceae and Rubiaceae dominate the woody flora; pteridophytes, Gramineae and Cyperaceae the herbs; Rubiaceae, Palmae and Annonaceae the climbers and Orchidaceae and pteridophytes the epiphyteS. Species confined to coastal habitats comprise 11.1% of the total flora; 73.5% are lowland forest species and the remaining 15.5% are non-tree species of open and frequently-disturbed sites. The vascular plant of flora of Bukit Timah Nature Reserve, the largest remaining patch of primary rain forest in Singapore, is also analysed. Its flora is similar to that of the forest component of the complete Singapore flora. The Singapore flora, in comparison with other tropical floras, is highly diverse, but appears depauperate in epiphytes and climbers.  相似文献   

17.
该研究通过对山西管涔山和五鹿山等区域采集的蜈蚣衣科地衣300余份标本的鉴定分析,结合已有报道,从物种多样性、空间分布特点、生境类型及区系成分等方面对蜈蚣衣科地衣进行研究,以明确中国蜈蚣衣科地衣物种组成及区系特点。结果表明:(1)中国蜈蚣衣科地衣共有7属197种54变种,饼干衣属(Rinodina)占绝对优势,约占蜈蚣衣科地衣总种数的30.5%。(2)中国蜈蚣衣科地衣多分布于新疆,蜈蚣衣属(Physcia)是该科中分布最广泛的属,但其中有26.4%的物种仅分布于单一地区。(3)蜈蚣衣科地衣生境类型多样,有树生、石生、藓丛生、土生和多生境5种,以多生境地衣为主(48.5%)。(4)中国蜈蚣衣科地衣的地理成分复杂,同时伴随多种区系成分,但以温带性质显著(占43.1%),东亚特色明显。(5)仅分布于中国的蜈蚣衣科地衣共4属10种,且主要分布于中国东北、西北和西南地区。  相似文献   

18.
In the tropical dry forest of the central Pacific coast of Mexico the pollination and reproductive success of the bombacaceous tree Ceiba grandiflora was negatively affected by habitat disruption. Two of the three bat species that function as effective pollinators for this species ( Glossophaga soricina and Musonycteris harrisoni) visited flowers found in trees in disturbed habitats significantly less than trees found in undisturbed habitats. A similar pattern was observed for the effective bat pollinator, Leptonycteris curasoae; however the difference was not significant. The three nectarivorous bats that functioned as effective pollinators of C. grandiflora also visited flowers to exclusively feed on pollen by biting or pulling off an anther (see Fig. S1 of Electronic Supplementary Material). The number of pollen grains deposited on stigmas from flowers in undisturbed areas was significantly greater than from flowers in disturbed habitats. The greater visitation rate and the greater number of pollen grains deposited on flowers from trees in undisturbed forest resulted in a significantly greater fruit set for trees in these areas. Our study demonstrates the negative effect that habitat disruption has on bat pollinators in tropical dry forest ecosystems and documents the negative consequences for the plants they pollinate.  相似文献   

19.
Conversion of natural habitats to agriculture reduces species richness, particularly in highly diverse tropical regions, but its effects on species composition are less well-studied. The conversion of rain forest to oil palm is of particular conservation concern globally, and we examined how it affects the abundance of birds, beetles, and ants according to their local population size, body size, geographical range size, and feeding guild or trophic position. We re-analysed data from six published studies representing 487 species/genera to assess the relative importance of these traits in explaining changes in abundance following forest conversion. We found consistent patterns across all three taxa, with large-bodied, abundant forest species from higher trophic levels, declining most in abundance following conversion of forest to oil palm. Best-fitting models explained 39–66 % of the variation in abundance changes for the three taxa, and included all ecological traits that we considered. Across the three taxa, those few species found in oil palm tended to be small-bodied species, from lower trophic levels, that had low local abundances in forest. These species were often hyper-abundant in oil palm plantations. These results provide empirical evidence of consistent responses to land-use change among taxonomic groups in relation to ecological traits.  相似文献   

20.
To compare community assemblage patterns in tropical northeastern and subtropical central eastern Australia across selected gradients and scales, we tested the relationship of species traits with phylogenetic structure, and niche breadth. We considered phylogenetic relationships across current‐day species in assemblages in relation to rain forest species pool sizes, and trait values along gradients including elevation and latitude. Trait values were quantified across scales for seed size, leaf area, wood density and maximum height at maturity for 1137 species and 596 assemblages using trait gradient analysis (TGA). Local assemblages of subtropical species had narrower trait ranges, and higher niche breadth values than corresponding assemblages of tropical species. Leaf size and seed size increased at low latitudes, and community phylogenetic structure was most strongly correlated with seed traits in the subtropics, reflecting dispersal and re‐colonization processes. Elevation accounted for little of the variance in community phylogenetic structure or trait variation across local and regional scales. Stable moist forest areas retained many species from ancestral rain forest lineages across a range of temporally conserved habitats; species within assemblages were less related; and rain forest assemblages had higher functional diversity, but lower niche breadth. This suggests that on average, assemblages of species in stable areas had greater trait variation and narrower distributions. Historic and recent rain forest contraction and re‐expansion can result in recolonized areas that are dominated by species that are more related (phylogenetically) than by chance, have smaller, widely dispersed seeds, and greater niche breadth (broader distributions).  相似文献   

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