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1.
Dung beetles are predominantly coprophagous and use mammalian faeces as their main food resource and for offspring rearing. However, these resources are generally ephemeral and scarce. The objective of this study was to verify the attractiveness to dung beetles of the faeces of nine native mammal species of the Cerrado biome in different trophic guilds. This study was conducted during the rainy season (October 2016 to March 2017) in two sensu stricto areas of the Cerrado in the Brasília National Park (PNB), Federal District, Brazil. Pitfalls containing faeces of nine mammals native to the region were used as bait (from three herbivores, three carnivores and three omnivores) for the collection of dung beetles. We collected 203 individuals and 19 species, and the most abundant species were Uroxys aff. thoracalis, Oxysternon palemo, Coprophanaeus spitzi and Diabroctis mirabilis. The most attractive faecal bait was from the omnivorous Chrysocyon brachyurus (32.67% of the individuals and 13 species). This study reveals variation in the attraction of dung beetles to native mammal dung of the Cerrado, with more abundance in the faeces of omnivores and carnivores and less in the faeces of herbivores. The species composition in the carnivore baits did not differ from that of the omnivore baits. These data indicate that changes in Scarabaeinae assemblages result from changes in mammal species such as those that have occurred in the Cerrado biome with the conversion to cattle production, which in recent years has caused intense fragmentation of habitats, expansion of agricultural and livestock activities and the introduction of exotic species. The mammal C. brachyurus, vulnerable to extinction in Brazil, should be a focus for future research, since its faeces support a great diversity of dung beetles in the Cerrado.  相似文献   

2.
Cetoniidae is a diverse family containing approximately 4,000 species, most of which feed on flowers and fruits. In Brazil, 72 species and 24 genera are recorded. Little is known about this family in the Central region of Brazil, and no research has previously been conducted in the ecologically important Cerrado biome. In this study, we evaluated the diversity and temporal variation of the Cetoniidae in an area of the Cerrado in the Federal District (Brazil) and verified whether the abundance and species richness were influenced by climatic variables. The study was carried out in an area of Cerrado sensu stricto at Água Limpa Farm in Brasília/DF. Beetles were collected weekly from October 2013 to September 2014 using 40 traps baited with banana and pineapple fermented with sugarcane juice. A total of 398 specimens comprising 8 genera and 15 species were collected. We observed temporal variation in abundance and richness of the Cetoniidae in direct relation to the climatic characteristics of the Cerrado, with a greater number of individuals and species appearing in the rainy season. Climatic variables such as temperature and humidity appear to have a significant effect on the diversity of Cetoniidae. This is the first study conducted on this family in Central Brazil.  相似文献   

3.
We present a survey of moth pollination in woody species of the Cerrado of Central Brazil. Although with the exception of Roupala montana (which has simple polysepalous flowers arranged in dense cymes) all moth pollinated species in this community have tubular flowers, or a pseudo-tube formed from a single folded petal in Qualea grandiflora, settling moth flowers (tube less than 15 mm) vs. hawkmoth flowers (tube more than 50 mm) are markedly different in size. Moths visit some 20 woody Cerrado species, but they are probably effective pollinators of only 13 species or ca.14% of the woody taxa studied, and even in these latter species they are often very sparse visitors. Nevertheless, it is notable that moths are pollinators for 21% of the 38 most commonly distributed woody Cerrado species. Moreover, the reproductive efficacy of the studied moth pollinated species was similar to that of species pollinated by other kind of vectors.  相似文献   

4.
Three new species of the Brazilian genus Luetzelburgia Harms (Leguminosae, Papilionoideae, Sophoreae sensu lato (Vataireoid clade)) are described and illustrated under the names Luetzelburgia harleyi D. Cardoso, L. P. Queiroz &; H. C. Lima, L. neurocarpa D. Cardoso, L. P. Queiroz &; H. C. Lima and L. purpurea D. Cardoso, L. P. Queiroz &; H. C. Lima. All three occur in the caatinga vegetation of the State of Bahia, Eastern Brazil. A discussion of the morphological characters distinguishing the new species from their close relatives, as well as an identification key to all known species of Luetzelburgia, are presented.  相似文献   

5.
Natural forests are often replaced by invasive alien trees on isolated oceanic islands. Adequate eradication of invasive trees should be conducted with the goal of biodiversity conservation, because islands support many endemic organisms that depend on native forests. An invasive alien tree, Bischofia javanica Blume (Euphorbiaceae), has invaded and replaced natural forests on the oceanic Ogasawara (Bonin) Islands, Japan, in the northwestern Pacific Ocean. To determine how the removal of B. javanica trees affects insect diversity, we examined flying beetles captured using Malaise traps in B. javanica forests on Hahajima. The abundance, species density, and species composition of wood-boring beetles (Coleoptera: Cerambycidae, Elateridae, Mordellidae, and Scolytidae) were compared between closed-canopy sites and gaps created by girdling B. javanica trees in alien forests during two seasons (June–July and October–November 2005). Of the collected beetles, 75.8, 87.5, 90.0, and 0.0% of cerambycid, elaterid, mordellid, and scolytid beetle species, respectively, were endemic to the Ogasawara Islands. More cerambycid, elaterid, and mordellid individuals were captured in June–July than in October–November; the number of scolytid individuals did not differ between seasons. More cerambycid, elaterid, and scolytid individuals were captured in artificial gaps than on the closed-canopy forest floor. Although fewer mordellid individuals were captured in gaps, more endemic mordellids were captured in gaps. More cerambycid and scolytid species were captured in artificial gaps than in closed-canopy areas. The positive responses of beetles to artificial gaps suggest that the removal of B. javanica increases beetle diversity and the abundance of endemic beetles.  相似文献   

6.
We examined the patterns of distribution, vectors of introduction, and potential ecological impacts of freshwater exotic species in Texas over the last 45 years. Currently, five species of exotic gastropods are established: channeled-type applesnail (Pomacea insularum), red-rim melania (Melanoides tuberculatus), quilted melania (Tarebia granifera), giant rams-horn snail (Marisa cornuarietis), and Chinese mysterysnail (Cipangopaludina chinensis). In contrast to the northern part of the US, where shipping appears to be the most important vector for the introduction of aquatic invasive species, aquarium and ornamental trade dominated among unintentional vectors of introduction of all freshwater exotics in Texas, resulting in different patterns of distribution, spread, and ecological impacts. The rate of spread of exotic gastropods in Texas varied from 39 waterbodies colonized over 18 years for P. insularum to only three waterbodies during last 45 years for C. chinensis. Four of five exotic gastropods were found in highly vulnerable aquifer-fed springs and rivers, which contain numerous endemic and endangered species. The fifth species, Pomacea insularum, is an agricultural pest. Potential negative ecological effects of exotic gastropods include impacts on wetlands and wetland restoration, competitive exclusion of native snails, and the introduction of exotic parasites, trematodes, which could infect fish and waterfowl, including federally protected species. Aquifer springs with stable temperature regimes are refuges for both cold and warm intolerant species. Handling editor: D. Dudgeon  相似文献   

7.
Over the past decade, four exotic tunicates (Styela clava, Ciona intestinalis, Botrylloides violaceus and Botryllus schlosseri) have been reported in the Brudenell estuary in Prince Edward Island (PEI), Canada. Styela clava was the first exotic tunicate to arrive in 1997, rapidly establishing, spreading, invading, and eventually becoming a nuisance in several estuaries of PEI. In the Brudenell estuary, S. clava remained the only exotic nuisance tunicate until 2003. In the fall of 2004, the vase tunicate C. intestinalis, was reported in low abundance, followed by the two colonial species, B. schlosseri and B. violaceus, reported in the spring of 2005. The abundance of C. intestinalis rapidly increased post-introduction, eventually replacing S. clava as the foremost nuisance species on mussel farms in the estuary. To date, C. intestinalis continues to colonize this estuary at epidemic proportions, resulting in the continuing drop of S. clava abundance. The current abundance of C. intestinalis is estimated at 5 cm−2, which is similar to S. clava abundance at its height in 2003. The 2006 abundance of S. clava is estimated to have fallen to near 0 cm−2. The dominance of C. intestinalis as a fouling organism on mussel farms is considered a serious threat to this aquaculture industry, mainly due to its unmanageable weight. The process of the detection, establishment, invasiveness, and eventual rise to nuisance level of exotic tunicates in the Brudenell River is presented.  相似文献   

8.
Raw  Anthony 《Annals of botany》2000,85(4):487-492
Native bees are effective pollinators of hot pepper plants,Capsicum annuum. In four gardens in south-central Brazil (Patosde Minas and Brasília) flowers of three cultivars receivedvisits from 16 species of bees in eight genera: Hylaeus(Colletidae),Dialictus, Halictus, Augochlora,Augochloropsis and Ceratalictus(Halictidae),Exomalopsis andBombus (Apidae). No other insects were observedto visit the flowers. Some species of bee occurred in more thanone garden. Individual bees gathered a full pollen load from18 to 47 flowers and visited one to eight plants on a singleforaging trip. In 76 shifts between plants, the bees made nineswitches between cultivars. It is suggested that small nativespecies of bees pollinate the flowers effectively and that theirsmall foraging areas are important in keeping the cultivarsof both hot and sweet peppers genetically distinct where severalcultivars are grown close together. Copyright 2000 Annals ofBotany Company Capsicum annuum, hot pepper, native bees, fruit set, Brazil  相似文献   

9.
Exotic species can invade and establish new habitats both as a result of their own traits, and as a result of the characteristics of the environment they invade. Here, we show that the abundance of the invasive submerged aquatic plant, Myriophyllum spicatum (Eurasian watermilfoil) is highly dependent on the conditions of the environment in a mesocosm experiment. M. spicatum is allelopathic towards epiphytic algae, and in the absence of algivorous snails, we found that the abundance of both algae and M. spicatum significantly increased with experimentally increased nutrient loading, while the abundance of native submerged macrophytes declined. However, when snails were present, snail biomass increased with increasing nutrient loading, and M. spicatum biomass was consistently low while native submerged macrophyte biomass was consistently high. Our results stress the importance of the interaction between species traits and environmental conditions when considering the invasiveness of certain exotic species and the invasibility of certain environments.  相似文献   

10.
Mesquita DO  Colli GR  Vitt LJ 《Oecologia》2007,153(1):185-195
We compare lizard assemblages of Cerrado and Amazonian savannas to test the ecological release hypothesis, which predicts that niche dimensions and abundance should be greater in species inhabiting isolated habitat patches with low species richness (Amazonian savannas and isolated Cerrado patches) when compared with nonisolated areas in central Cerrado with greater species richness. We calculated microhabitat and diet niche breadths with data from 14 isolated Cerrado patches and Amazon savanna areas and six central Cerrado populations. Morphological data were compared using average Euclidean distances, and lizard abundance was estimated using the number of lizards captured in pitfall traps over an extended time period. We found no evidence of ecological release with respect to microhabitat use, suggesting that historical factors are better microhabitat predictors than ecological factors. However, data from individual stomachs indicate that ecological release occurs in these areas for one species (Tropidurus) but not others (Ameiva ameiva, Anolis, Cnemidophorus, and Micrablepharus), suggesting that evolutionary lineages respond differently to environmental pressures, with tropidurids being more affected by ecological factors than polychrotids, teiids, and gymnophthalmids. We found no evidence that ecological release occurs in these areas using morphological data. Based on abundance data, our results indicate that the ecological release (density compensation) hypothesis is not supported: lizard species are not more abundant in isolated areas than in nonisolated areas. The ecology of species is highly conservative, varying little from assemblage to assemblage. Nevertheless, increases in niche breadth for some species indicate that ecological release occurs as well. Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users.  相似文献   

11.
12.
Achatina (Lissachatina) fulica was introduced in Brazil in the 1980s for commercial purposes (“escargot” farming) and nowadays, mainly by human activity, it is widespread in at least 23 out of 26 Brazilian states and Brasília, including the Amazonian region and natural reserves, where besides a general nuisance for people it is a pest and also a public health concern, since it is one of the natural intermediate host of Angiostrongylus cantonensis, ethiological agent of the meningoencephalitis in Asia. As Brazil is experiencing the explosive phase of the invasion, the Laboratório de Malacologia do Instituto Oswaldo Cruz/Fiocruz has been receiving samples of these molluscs for identification and search for Angiostrongylus cantonensis and Angiostrongylus costaricensis larvae. While examining samples of A. fulica different nematode larvae were obtained, including Aelurostrongylus, whose different species are parasites of felids, dogs, primates, and badger. Morphological and morphometric analyses presented herein indicated the species Aelurostrongylus abstrusus, as well as the occurrence of other nematode larvae (Strongyluris-like) found in the interior of the pallial cavity of A. fulica. This is the first report in Brazil of the development of A. abstrusus infective larvae in A. fulica evidencing the veterinary importance of this mollusc in the transmission of A. abstrusus to domestic cats. Since the spread of A. fulica is pointed out in the literature as one of the main causative spread of the meningoencephalitis caused by A. cantonensis the authors emphasize the need of sanitary vigilance of snails and rats from vulnerable areas for A. cantonensis introduction as the port side areas.  相似文献   

13.
Summary  A new and probably endemic species of Cambessedesia DC. is described from campo rupestre vegetation, as part of a floristic survey of Melastomataceae from the S?o José mountain range, Tiradentes District, Minas Gerais State, Brazil. Miscellaneous  Accepted for publication April 2008.  相似文献   

14.
We examined the entire spatial distribution of a narrow endemic shrub (Coccoloba cereifera, Polygonaceae) in Serra do Cipó, Brazil. We tested the hypothesis that a narrow endemic species would show a gradual decline in either size and density towards the edges of its distribution. The contribution of soil specificity and post-fire growth to C. cereifera abundance and distribution were also investigated. C. cereifera showed multimodal and highly aggregated distribution pattern at several scales, from 25 m2 to 3000 m2 (blocked quadrat variance analyses). This pattern seems to be strongly related to the predominance of clonal recruitment and to the close association of the species to sandfields, which have discrete distribution between gallery forests and rocky outcrops. Population density did not decline towards the edge of the species distribution. Plants near the distribution boundaries had slightly more leaves and more inflorescences per plant (p<0.005), but there was no significant change in the mean number of ramets per clone. The absence of large plants in some populations at the center of the species distribution may be related to the higher frequency of fire in this region, killing aerial plant parts. Nearly all aggregations had inverse-J shaped size-distribution, suggesting effective recruitment of ramets, most frequently via asexual reproduction. Similar patterns of plant abundance may be common in fire-prone habitats characterized by infertile, and well-drained soils since these areas generally have high numbers of endemic plants, with strong soil specificity. Possible mechanisms for the observed pattern are discussed considering current models concerning distribution of abundance of species.  相似文献   

15.
Adiantum diphyllum, a species endemic to the coastal forests of Bahia State, Brazil, is characterized and distinguished from other species ofAdiantum with anastomosing veins, elongate sori, and venuloid idioblasts.
Adiantum diphyllum, uma espécie endêmica das florestas costeiras do leste do Brasil. é caracterizada e distinta das outras espécies deAdiantum com nervuras anastomosadas, soros alongados e idioblastos entre as nervuras.
  相似文献   

16.
Five new species ofHypolytrum Rich. from South America are described and illustrated.Hypolytrum amorimii andH. jardimii, both of sect.Bullata T. Koyama, are species with pseudopetioles and colored leaves, and endemic to the rain forest of southeastern Brazil.Hypolytrum bahiense (sect.Hypolytrum), a species with a lax synflorescence and two, free and lightly scabridulous floral bracts, is endemic to the rain forest of southeastern Bahia, Brazil.Hypolytrum leptocalamum (sect.Hypolytrum), a species with lax synflorescence and spike ellipsoid to cylindrical, is restricted to area of tepuis in the Guayana Highland (Brazil, Guyana, and Venezuela).Hypolytrum paraense (sect.Hypolytrum), a species with three, partly connate and densely scabridulous floral bracts, is restricted to the rain forest of the Amazon Basin, in the state of Pará, Brazil.  相似文献   

17.
Two new narrow endemic species ofBegonia from the Atlantic coastal forests of Brazil,B. espiritosantensis andB. ibitiocensis, are described and illustrated.Begonia schenkii var.calvescens, an endemic taxon from the states of Santa Catarina and Rio Grande do Sul, is transferred to species rank, and described and illustrated. A distribution map is provided for all three taxa.  相似文献   

18.
Edges between forest and non-forest habitats often have significant effects on forest microclimate and resource availability, with corresponding effects on species composition and abundance. Exotic species are often increased in abundance near forest edges. This increase in abundance could be either because of the increase in resource availability near edges, or because of increased dispersal into forest edges. We measured species composition and a set of geospatial variables on transects at 66 edges in the North Carolina Piedmont in an attempt to distinguish between these two factors. Mantel tests show that species composition is significantly different in forest edges than in the forest interior, but that this effect only penetrates about 5 m into the forest. Indicator species analysis finds several species that are indicative of edge communities, including trumpet vine (Campsis radicans), two drought-tolerant oak species (Quercus stellata and Q. falcata), a serviceberry (Amelanchier arboreum), and a common exotic species, tree-of-heaven (Ailanthus altissima). Poisson regression techniques showed that in both the seedling and tree strata of the forest, exotic species increased in abundance on flat sites with a high potential seed source. Mapping predicted exotic species abundance onto the landscape. We find that large-scale variation in exotic species abundance is due mostly to variation in potential seed sources, while small-scale variation relates more to edaphic factors. Our results stress that both dispersal and environmental filters are important for determining exotic species abundance, but potentially the filters operate at different spatial scales.  相似文献   

19.
We report the occurrence of the orange-striped green anemone Diadumene lineata (Verrill 1871) (=Haliplanella lineata) in salt marshes at the Bahía Blanca Estuary for the first time in August 2005. We also found this species attached to roots and stems of Spartina alterniflora, an association that has never been registered before. After their determination, sampling was performed during a year to evaluate seasonal abundance of this sea anemone. Results showed that D. lineata was present through the whole year, indicating the existence of a stable population. All individuals sampled were found attached to roots or stems of S. alterniflora, with the higher abundances detected in summer. Further studies are necessary to precise the potential effects of this exotic sea anemone on salt marsh communities.  相似文献   

20.
Invasion of habitats by exotic shrubs is often associated with a decrease in the abundance of native species, particularly trees. This is typically interpreted as evidence for direct resource competition between the invader and native species. However, this may also reflect indirect impacts of the exotic shrubs through harboring high densities of seed predators––known as apparent competition. Here I present data from separate seed predation experiments conducted with two shrub species exotic to North America; Rosa multiflora, an invader of abandoned agricultural land, and Lonicera maackii, an invader of disturbed or secondary forest habitats. Both experiments showed significantly greater risks of seed predation for tree seeds located under shrub canopies when compared to open microhabitats within the same site. These results indicate the potential importance of indirect impacts of exotic species invasions on native biota in addition to the direct impacts that are typically the focus of research.  相似文献   

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