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1.
Folivory has evolved in all primate radiations but the relative importance of resource quantity and nutritional quality of food is controversial. To understand how food abundance and different nutrients affect a folivorous diet, we investigated food composition of the leaf-eating lemur Avahi meridionalis. From June to December 2004, we conducted 26 nights of focal observation (256.1 h) in Sainte Luce pluvial littoral forest (southeast Madagascar) and recorded feeding behavior of 4 radiocollared individuals. Within the subjects’ home ranges, we recorded vegetation characteristics (morphospecies, phenology, diameter at breast height) and sampled food and nonfood items for chemical analyses. A. meridionalis did not eat fruit but only leaves and flowers and did not base their choice on food abundance. Adult leaves eaten were higher in easily soluble protein than adult leaves that were not consumed. The subjects ate young leaves and flowers as soon as they became available. These young leaves contained the same concentrations of soluble protein, higher concentrations of crude protein, and lower concentrations of acid detergent fiber and sugar than mature food leaves. A. meridionalis ate leaves with condensed tannins, alkaloids, and intermediate concentrations of polyphenolics. Contrary to previous studies that considered Avahi spp. a specialist, A. meridionalis acted as leaf-eating generalists with moderate selectivity, based on nutritional quality and tolerance of a wide array of plant secondary metabolites. This illustrates the dietary flexibility within a single genus of primates that seems to be driven by environmental constraints rather than morphological or physiological adaptations.  相似文献   

2.
Anuran males emit advertisement calls for the purpose of attracting females and repelling conspecific males. Call transmission is influenced by the acoustics of the propagation environment, including vegetation. Thus, forestry monocultures of non-native trees represent artificial environments that could modify call transmission. These monocultures have substituted large areas of Atlantic Forest in southern Brazil, representing a conservation challenge. Considering this context, we hypothesized that anurans have calls that are less attenuated in their native environment than in forest plantations. To test it, we performed sound transmission experiments using calls of three anuran species native to southern Brazil: Boana bischoffi, B. leptolineata, and Hylodes meridionalis. We compared sound attenuation between the native forest and forestry monocultures (Eucalyptus sp. and Pinus sp. forests), and included distance from the sound source, air temperature, humidity, and vegetation density as cofactors in linear mixed models. Our results show that the advertisement calls of the two tree frogs (Boana) attenuate less in tree plantations than in native forests, while the third species shows either no differences or less attenuation in native forests. Our results can be understood according to differences in natural history and microhabitat use among the studied species. The two tree frog species vocalize perched from vegetation so their calls become better transmitted in forestry monocultures, which have fewer trees than the native forest. On the other hand, H. meridionalis calls from rocks on streams and the propagation is finely tuned to this peculiar microhabitat. We discuss the conservation implications of our findings for anurans and for the Atlantic Forest. Abstract in Portuguese and Spanish are available with online material.  相似文献   

3.
We obtained DNA sequence data from mitochondrial (cytochrome b) and nuclear genes (myoglobin and ornithine decarboxylase) to reconstruct the phylogenetic relationships among eight species of shrikes (Lanius). Phylogenetic analyses based on maximum parsimony, maximum likelihood and Bayesian inference all converged into a congruent topology and defined several well-supported clades. Our multi-gene approach based on nucleotide sequences from fast-evolving and conserved genes strongly supported the paraphyly of Southern Grey Shrikes (Lanius meridionalis). The Canary Islands subspecies (L. m. koenigi) differed significantly from its European counterpart (L. m. meridionalis). Furthermore, the genetic distinctiveness of L. m. koenigi was confirmed by ISSR genomic fingerprinting. By contrast, we did not find evidence to distinguish the Canarian Southern Grey Shrike from L. m. algeriensis on the African mainland (Tunisia), and therefore these two taxa may be considered as synonymous. Together, they correspond to a separate species. The origin of the taxa investigated in this study might have originated about 6 Mya at the Miocene/Pliocene boundary when a remarkable worldwide faunal turnover and global vegetation change occurred. The Lanius genus represents a complex and taxonomically challenging group that requires additional research.  相似文献   

4.
This study provides a view of vegetation types dominated by Sesleria species in the Western Carpathians (Sesleria caerulea, S. heufleriana, S. tatrae, and S. uliginosa). We also took into account characteristics/traits such as plant life forms, autochthonous status, endemism, and ploidy level occurring within each relevé in our data set. Altitude and Ellenberg indicator values derived for each relevé were considered as well. Eight vegetation types/formations/habitats were recognized in a data set of 942 phytosociological relevés: (1) synanthropic vegetation, (2) rock fissures and screes, (3) alpine grasslands and heaths, (4) mesic grasslands and pastures, (5) springs and fens, (6) forests, (7) xerophilous shrubland, and (8) high-mountain scrubs (krummholz). Results corroborated and clearly emphasized that Sesleria caerulea has the widest ecological amplitude of all studied species because the species occurred among all studied vegetation types. Sesleria tatrae was present only in several vegetation types occurring from montane to alpine vegetation belts in the highest mountains. Sesleria heufleriana and S. uliginosa were recorded only in low-altitude areas. The difference between them lies mainly in the dampness of each locality. Sesleria heufleriana was frequently found in xerophilous communities, whereas S. uliginosa preferred humid habitats of springs and fens.  相似文献   

5.
V. H. Jolly 《Hydrobiologia》1953,5(3):309-313
Summary The consideration of specimens from many localities in New Zealand shows that the genus Bosmina is represented by but a single species. This species is maintained to be B. meridionalis by the author. Dorsal incisures are shown to occur on the mucro in juvenile females which suggests the possible identity of this species with B. hagmanni Stingelin. Should the above species prove to be identical the specific name meridionalis is shown to take precedence.
Résumé L'examen de nombreux specimens pris dans plusieurs endroits de la Nouvelle Zéelande démontre que le genre Bosmina n'est représenté que par l'espèce B. meridionalis. Des incisions dorsales sont visibles sur le mucro chez les jeunes femelles, ce qui suggère l'idée que cette espèce est identique à B. hagmanni Stingelin. Si ces espèces sont vraiment identiques, le nom spécifique B. meridionalis doit avoir la préséance.
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6.
Genetic differentiation of Hyla arborea molleri and H. meridionalis was studied through allozyme electrophoresis and through essays of artificial hybridization. Samples were taken at several localities in Portugal, where these species occur either in sympatry or allopatry, and at one locality in France. Of the 21 presumptive loci analyzed, 6 were monoallelic, while 9 loci were discriminative between both species. A relatively high level of genetic differentiation was found between the two species (NEI's D = 0.725), contrasting with their morphological similarity. Remarkably low levels of genetic variability were found within species, with greater differentiation found among samples of H. meridionalis than of H. a. molleri. Although the capacity for interspecific hybridization was low, hybrid embryos resulted from both reciprocal crosses, but with much greater success in the cross ♂H. a. molleri x δH. meridionalis. Hybrids showed greater similarity with the male parent, and showed heterozygote allozymic phenotypes for discriminative loci. Results are compared with those of similar studies on the same and different species of Hyla, and differentiation of H. a. molleri and H. meridionalis is discussed in relation to their taxonomic status and origin.  相似文献   

7.
Some aspects of the seasonal distribution of flagellates in mountain lakes   总被引:2,自引:2,他引:0  
E. Rott 《Hydrobiologia》1988,161(1):159-170
In a larger regional survey in Tyrol, phytoplankton species composition and biovolume of mid-altitude and high-mountain lakes was studied. Results from eight lakes showed that flagellates (mainly Chrysophyceae, Dinophyceae, and Cryptophyceae) are important components of the phytoplankton.In the mid-altitude lakes a spring and an autumn maximum of Chrysophyceae as well as a summer maximum of large dinoflagellates are observed, whereas Cryptophyceae and Dinophyceae show irregular distributions. In the high-mountain lakes the seasonal variations of phytoplankton, including flagellates, are limited by the long duration of the winter situation. However similar sequences of phytoplankton assemblages as in the midaltitude lakes can be observed. Flagellates in high-mountain lakes are important to sustain phytoplankton standing crop under the winter snow and ice cover.In order to show similarities and differences of high-mountain and mid-altitude lakes, vertical profiles of phytoplankton from three lakes and seasonal patterns of Gymnodinium uberrimum from two lakes are compared. In addition the patterns of cryptomonads differing in their ecological requirements (Cryptomonas spp. and Rhodomonas minuta) are shown for a meromictic mid-altitude lake.  相似文献   

8.
This paper presents a survey of high-altitude plant communities which occur in the Western Carpathians with an enumeration of the characteristic, transgressive and differential species of the individual alliances, orders and classes. It describes the tall-herb vegetation (Mulgedio-Aconitetea) and communities of the subalpine shrubs (Betulo carpaticae-Alnetea viridis), the montane and alpine calcareous swards (Elyno-Seslerietea), the wind-exposed cryophilous swards on ridge edges with low snow cover (Carici rupestris-Kobresietea bellardii), the chionophilous communities of snow beds and snow fields (Salicetea herbaceae), the arctic-boreal dwarf-shrub heathlands (Loiseleurio-Vaccinietea), the alpine acidophilous grasslands (Caricetea curvulae) and the high-mountain mat-grass swards of the alliance Nardion strictae (Nardetea strictae).  相似文献   

9.
黄河三角洲植被空间分布特征及其环境解释   总被引:2,自引:0,他引:2  
安乐生  周葆华  赵全升  王磊 《生态学报》2017,37(20):6809-6817
为了解黄河三角洲地区植被空间分布与环境因子之间的关系,通过局地植被样方调查、区域遥感影像提取归一化植被指数(NDVI)及地形高度、地下水位埋深、表层土壤Cl~-含量等环境数据采集,综合样地植被与环境数据进行了除趋势对应分析(DCA)和除趋势典范对应分析(DCCA),并对区域NDVI与主要环境变量进行了单因子相关性分析和多元逐步回归分析。结果显示:DCA排序可将黄河三角洲植被分为翅碱蓬、柽柳-翅碱蓬、芦苇-柽柳、芦苇4个主要群落类型(群丛),DCCA与DCA排序图总体相似,但DCCA更清晰地表明其第一轴主要代表的是潜水Cl~-浓度等关键水盐因子,且随着水土环境系统盐分含量的减小,群落由翅碱蓬逐渐向芦苇演变。区域典型植被群落和NDVI分布格局与变化趋势受地下水位埋深和潜水Cl~-浓度2个环境因素影响较大(NDVI与2个环境变量间建立的二元回归方程R~2=0.57),而土壤Cl~-含量的植被效应实际上受地下水位埋深和潜水Cl~-浓度的影响。在区域地下水普遍浅埋条件下,地下水成为影响植被生长与分布的生态环境最敏感要素,而地下水位埋深和潜水Cl~-浓度是这一要素中的2个关键因子,尤其是后者梯度变化对天然植被分布格局起重要的控制作用。  相似文献   

10.
Linuparus White, 1847 comprises three extant species, Linuparus trigonus (Von Siebold, 1824), L. sordidusBruce, 1965, and L. somniosusBerry and George, 1972, as well as 32 fossil species. Most fossil records are from North America and Europe, but the extant species are all confined to the Indo-West Pacific. Different colour forms in L. trigonus and L. sordidus have been noted, with Northern Hemisphere specimens generally darker in colour for both species. The phylogenetic relationships of the extant Linuparus species, including the colour forms, were investigated using mitochondrial 12S rRNA and COI gene sequence analysis. We found no genetic evidence to differentiate the colour morphs of L. sordidus, but the two colour forms of L. trigonus were clearly distinct at the species level. This is supported morphologically by a consistent difference in the shape of the thoracic sternum between the two forms. The paler coloured Southern Hemisphere form is described as a new species, L. meridionalis. Phylogenetic analysis shows that L. trigonus and L. meridionalis sp. nov. are derived sister taxa, while L. somniosus is basal within the genus. Thus the present results support the previous hypothesis that Linuparus was originated in shallow water.  相似文献   

11.
Invasive plants are degrading wildlands around the globe by displacing native species, reducing biodiversity, and altering ecological functions. The current approach of applying herbicides to invasive plants in wildlands has not been effective at curtailing their expansion and, in certain circumstances, may do more harm than good. Preventing the spread of invasive species has been identified as an important strategy to protect wildlands. However, few prevention strategies have actually been tested. We hypothesized that establishing competitive vegetation next to infestations would increase the biotic resistance of the plant community to invasion and decrease the invasive species propagule pressure beyond the competitive vegetation. To evaluate this, we established twelve competitive vegetation barriers in front of invasive annual grass, Taeniatherum caput-medusae (L.) Nevski, infestations. The non-native perennial grass Agropyron desertorum (Fisch. ex Link) Schult. was seeded into plant communities adjacent to the infestations to create the competitive vegetation barriers. Soil nutrient concentrations and the spread of T. caput-medusae were compared between where A. desertorum was seeded and not seeded (control treatment) 3 years after treatment. Less T. caput-medusae and lower soil ammonium and potassium concentrations in the competitive vegetation barrier than control treatment (P ≤ 0.01) suggest that establishing competitive vegetation increased the biotic resistance of the plant communities to invasion. Taeniatherum caput-medusae cover and density in the plant communities protected by the competitive vegetation barrier (locales across the barriers from the infestations) were ~42- and 47-fold less, respectively, than unprotected plant communities (P < 0.01). This suggests that invasive plant propagule pressure was decreased in the plant communities protected by competitive vegetation barriers. The establishment of competitive vegetation around infestations may be an effective strategy to prevent or at least reduce the spread of invasive plant species.  相似文献   

12.
Length‐weight relationships (LWRs) were evaluated for 11 fish species from the Yibin reach of the upper Yangtze River, southwest China. Samples were collected from April 2012 to January 2013. Length‐weight relationships for 11 species were unknown to FishBase, and new maximum lengths are recorded for five species. Results indicate that parameter b ranged from 2.586 (Sinibotia superciliaris) to 3.164 (Rhinogobio ventralis), and r2 values ranged from 0.931 (Sinibotia superciliaris) to 0.996 (Silurus meridionalis).  相似文献   

13.
The authors have studied and analyzed the role of lichens in epilithic-lichen, stony, Alectoria, Dryas, fruticose-lichen, fescue, Cobresia, and yernik tundras, integral components of high-mountain vegetation.  相似文献   

14.
在黄河中游郑州荥阳段,选择了5种河滨湿地植物群落进行根系和土壤性状特征研究,以期阐明不同植物群落的根系分布规律与土壤性状的关系,为河滨湿地植物群落组成以及土壤质量恢复提供科学参考。结果表明(1)在0—40 cm土层,根生物量密度与根长密度的平均值均表现为:芦苇群落(Phragmites australis)和芦苇-狗牙根(Cynodon dactylon)群落均大于芦苇-拂子茅(Calamagrostis epigeios)-狗牙根群落、拂子茅-狗牙根群落、拂子茅-狗牙根-水莎草(Juncellus serotinus)群落。拂子茅-狗牙根、芦苇-拂子茅-狗牙根、拂子茅-水莎草-狗牙根三种植物群落类型下根生物量密度、根长密度在0—20 cm表层土壤较大,芦苇群落和芦苇-狗牙根群落的根生物量密度、根长密度在10—40 cm的土层较大。(2)黄河河滨湿地芦苇群落、芦苇-狗牙根群落的土壤以粉粒为主,拂子茅-狗牙根群落、芦苇-拂子茅-狗牙根群落、拂子茅-狗牙根-水莎草群落的土壤主要以砂粒为主。在0—40 cm土层,芦苇群落、芦苇-狗牙根群落的土壤含水率、土壤有机质、有效氮和有效磷含量均显著高于...  相似文献   

15.
In the southern Andes mountains (27–\(39{^{\circ }}\hbox {S}\)) Azorella madreporica and Laretia acaulis, two Apiaceae cushion plant species commonly known as yaretas, conform a well-established altitudinal vegetation belt along the lower Andean zone. These species have been considered as fundamental components of several ecological dynamics within their communities; however, high-mountain ecosystems are increasingly threatened worldwide by natural and anthropogenic pressures and the southern Andes are not the exception. Recognizing that genetic information is crucial for the success of any conservation or restoration initiative in wild populations, we developed and cross-amplified 28 specifically designed microsatellite markers (14 in A. madreporica and 14 in L. acaulis), and also tested the cross amplification of 25 markers from the related species Azorella selago. In a region which is particularly vulnerable to global change trends, this new polymorphic microsatellite loci will be useful in the study of the genetic diversity of these high-mountain cushion plants, which are pivotal in the structuring of their native ecosystems.  相似文献   

16.
Primate responses to habitat alteration vary depending on the species’ dietary guild and forest type. Leaves from secondary vegetation can provide nutritious resources to folivorous primates, whereas frugivores, burdened with a scattered spatial and temporal distribution of fruiting resources, require larger home ranges, potentially limiting their ability to cope with altered landscapes. Within coastal southeastern Madagascar, we sought to determine whether two lemur species occupying contrasting ecological niches respond differently to the changing features of their degraded and fragmented habitat. We conducted behavioral observations between 2011 and 2013 on frugivorous collared brown lemurs (Eulemur collaris) and folivorous southern bamboo lemurs (Hapalemur meridionalis). To estimate the ability of lemurs to use pioneer species, we categorized all plants used for feeding and resting as fast growing, mid-growing, or slow growing. We fitted general linear mixed-effects models, one for each plant growth category with monthly proportional use rates as the dependent variable, and included species (E. collaris and H. meridionalis), activity (feeding and resting), and season (dry and wet) as fixed effects. Our results show that E. collaris used both slow- and mid-growing plant species most often, while H. meridionalis were more likely to use fast-growing plants, which indicated an ability to use secondary/disturbed vegetation. Frugivorous E. collaris appear more limited by climax plants, while folivorous H. meridionalis appear to be slightly more adaptable, a finding that is consistent with that for other primate folivores.  相似文献   

17.
Kuo  Chu-Chia  Su  Yu  Liu  Ho-Yih  Lin  Cheng-Tao 《Plant Ecology》2021,222(8):933-951

Mountain ecosystems are globally among the most vulnerable to the impacts of global warming. This study is carried out on high-mountain summits dominated by dwarf bamboo, Yushania niitakayamensis, in the alpine zone of subtropical Taiwan. A total of six summits were selected using a multi-summit approach, following the common protocol of the Global Observation Research Initiative in Alpine Environments (GLORIA). To assess the climate change effects, we used the soil temperature and statistical downscaling precipitation data to analyze the climatic changing patterns, also applied enhanced vegetation index (EVI) and vegetation diversity index to assess the vegetation responses among summits along the timeline. The results showed that the temperature has a significant increase in all summits, especially in winter. The annual chilling days have reduced around 50% from 2010 to 2019, which would imply the extension of plant growing season. The EVI values showed a tendency to increase over time. Furthermore, the long-term trend of EVI had an abnormal drop in 2018. This coincided with low precipitation and extremely high temperature in the early growing season, which may have caused water shortage and a decline in plant growth. Although the temperature was increasing significantly, the species diversity was slightly increasing in the first survey, but significantly decreased in the third survey. We suggest that the increase in temperature and the extension of the growing season might have led to the expansion of the bamboo species Y. niitakayamensis. Its expansion, combined with an extreme climate event could have caused the decline in species diversity.

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18.
Abstract Oryza meridionalis is an annual emergent wetland grass which produces between 26 and 260 kg seeds ha-1 annually. Seed shed occurs at the end of the wet season, when the plains are usually still partially flooded. The juvenile recruitment of key native vertebrate species, such as the Magpie Goose (Anseranus semipalmata) and the Dusky Plains Rat (Rattus colletti), coincides with seed shed. This study investigated predation of O. meridionalis seeds at two sites on the South Alligator River floodplain in monsoonal Australia. The effects of inundation and the presence of a background density of seeds on seed removal were investigated by stratified sampling with respect to position down the topographic slope, to include the ‘dry’ floodplain margin, ‘damp’Oryza zone, and ‘flooded’Oryza zone. The effect of seed lot size on the proportion of seed removed was also investigated, and exclosures were used to identify the principal predator group. The proportion of seeds removed was not affected by the presence/absence of a background of seeds nor the number of seeds placed in experimental ‘lots’. The majority of seeds (75%) was consumed by vertebrate predators (most likely the abundant Dusky Plains Rat). Inundation afforded some protection from predation. Despite high losses of seeds exposed to predators, O. meridionalis is an abundant and widespread species on these floodplains, possibly because of the protection from predation afforded by inundation to those seeds which are shed into the water column. It is likely that there is a complex interaction between topography, rainfall and predator and prey relationships, which ultimately determines the importance of seed removal for the maintenance of populations of O. meridionalis. These high losses of seeds to predation have implications for wetland rehabilitation where seed broadcasting is proposed.  相似文献   

19.
To reconstruct the vegetation and fire history of the Upper Engadine, two continuous sediment cores from Lej da Champfèr and Lej da San Murezzan (Upper Engadine Valley, southeastern Switzerland) were analysed for pollen, plant macrofossils, charcoal and kerogen. The chronologies of the cores are based on 38 radiocarbon dates. Pollen and macrofossil data suggest a rapid afforestation with Betula, Pinus sylvestris, Pinus cembra, and Larix decidua after the retreat of the glaciers from the lake catchments 11,000 cal years ago. This vegetation type persisted until ca. 7300 cal b.p. (5350 b.c.) when Picea replaced Pinus cembra. Pollen indicative of human impact suggests that in this high-mountain region of the central Alps strong anthropogenic activities began during the Early Bronze Age (3900 cal b.p., 1950 b.c.). Local human settlements led to vegetational changes, promoting the expansion of Larix decidua and Alnus viridis. In the case of Larix, continuing land use and especially grazing after fire led to the formation of Larix meadows. The expansion of Alnus viridis was directly induced by fire, as evidenced by time-series analysis. Subsequently, the process of forest conversion into open landscapes continued for millennia and reached its maximum at the end of the Middle Ages at around 500 cal b.p. (a.d. 1450).  相似文献   

20.
M. Terzi  R. Di Pietro 《Plant biosystems》2016,150(6):1364-1369
The thermophilous chasmophytic vegetation on limestone of the Adriatic Region has been arranged in the endemic order Centaureo-Campanuletalia (class Asplenietea trichomanis). The distribution range of the order covers a large area around the Adriatic Sea – from the south and north east of Italy to Slovenia, Croatia, Bosnia i Hercegovina, Montenegro and Albania. The Centaureo-Campanuletalia or its subordinated syntaxa are quoted in the main syntaxonomic synopses of the Region as well as in technical reports. The critical analysis of the nomenclature of the order, based on the International Code of Phytosociological Nomenclature (ICPN), showed many invalid or incorrect names while it is evident that the usage of correct names in scientific literature is crucial, both for the advances of syntaxonomic knowledge and their application for practical purposes. This paper presents a revision of the nomenclature for the Centaureo-Campanuletalia and related syntaxa in order to stabilize this nomenclature at least at alliance level. As a result, three syntaxa were validated (Centaureo dalmaticae-Campanuletalia pyramidalis, Centaureo cuspidatae-Portenschlagiellion ramosissimae, Inulo verbascifoliae-Centaureetum cuspidatae) and five others were lectotypified.  相似文献   

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