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1.
A total of 139 collembolan species from 55 genera were found in coastal tundra near the settlement of Lavrentiya in the eastern part of the Chukchi Peninsula. The local fauna of the region is quite “Beringian” in species composition but its structure appears to be in full agreement with the known characteristics of southern tundra faunas of other sectors in the Arctic. The specificity of collembolan complexes of the main plant associations in the studied area is not very high because the predominant collembolan species usually inhabit a wide range of communities. The performed study on Collembola fails to confirm the conventional view of a significantly higher diversity of northeastern Palaearctic faunas. Despite the rather southern position of the studied coastal tundra, the species richness of its collembolan fauna seems to be the same as or only slightly higher than that of analogous landscapes in the other Arctic sectors. The apparent discrepancy between relatively low diversity of Collembola at the local level as shown herein and its rich regional fauna may be the result of increased differentiation of the collembolan fauna of the region characterized by very complex orography and extremely contrasting climatic conditions.  相似文献   

2.
Although their functional importance in ecosystems is increasingly recognized, soil‐dwelling micro‐arthropods are usually poorly known in comparison with their above‐ground counterparts. Collembola constitute a significant and species‐rich component of the soil biodiversity, but it remains a woefully understudied group because of the taxonomic impediment. The ever‐increasing use of molecular taxonomic tools, such as DNA barcoding, provides a possible solution. Here, we test the use of this approach through a diversity survey of Collembola from the vicinity of Churchill, Manitoba, Canada, and compare the results with previous surveys in the same area and in other sub‐Arctic regions. The systematic barcoding campaign at Churchill revealed a diverse collembolan fauna consisting of 97 species‐level MOTUs in six types of habitats. If all these MOTUs are confirmed as species, this richness would be far higher than prior records for Arctic Canada and could lead to reconsider the actual diversity of the group in Arctic environments.  相似文献   

3.
Abstract The collembolan faunas of 30 bauxite mines rehabilitated by a range of different methods between 1966 and 1977, and three forest plots were surveyed in the spring and summer of 1978–79 with the aim of studying the restoration of decomposer activity in degraded areas. The rehabilitation methods included seeding and planting with a variety of native or exotic plant species. Physical and botanical parameters of the plots were also measured. Sixty species of Collembola were collected from the rehabilitated areas; nine of the 28 species found in the forest plots were not present on the mined sites. Principal components analysis suggested that the species richness of the collembolan community in rehabilitated areas is positively correlated with plot age. A parametric correlation analysis using a number of collembolan community characteristics revealed that, among other factors, the development of a species rich collembolan fauna is positively correlated with plant species richness and diversity, and also with percentage plant cover. These results provide directions for improving rehabilitation practices.  相似文献   

4.
Opencast mining causes severe environmental impacts by removing the vegetation cover and depleting the fauna. Reforestation methods using native species and diverse pre- and post-disturbance approaches aim to recover the original richness and diversity of species found before the impact. Bioindicators are powerful tools to evaluate the restoration of the original environmental conditions in disturbed areas. We used species richness, endemism and diversity measurements of Collembola to compare successional stages in reforested sites of different ages compared with a control undisturbed area. Richness and abundance of Collembola were subjected to correlation analysis with age of plots and vegetational variables. Areas that were reforested for up to 16 years supported a much lower Collembola species richness than undisturbed areas. Both the age of reforestation plots and vegetation variables (number of trees, diameter of crowns, depth of leaf litter and tree species richness) were positively and significantly correlated to collembolan abundance and richness. The results showed that the diversity of the 16-year-old plot was significantly higher than that of younger areas, but significantly less diverse than that of the control area. Endemic species were more sensitive to disturbance than non-endemics. Thus, species richness and diversity of soil Collembola can be only partially restored with appropriate reforestation methods, and although it takes many years, to some extent even endemic species can be gradually restored. Nevertheless, the maintenance of undisturbed diversity reservoirs linked by ecological corridors to reforested plots is imperative, as only undisturbed areas can support most of the endemic species able to re-colonize reforested sites.  相似文献   

5.
The collembolan fauna of the Pinega State Reserve (Arkhangelsk Province) was examined. The study area is highly specific due to its karst topography. In all, 126 Collembola species were recorded in the reserve, a significant fraction of their diversity being restricted to karst habitats. Several species that had never been recorded in plain forest biotopes were of special interest. Such forms with distribution ranges mainly limited to the tundra zone comprised about 10% of the local fauna. Regarding the longitudinal sizes of the ranges, this group was not homogeneous and included both widespread circumpolar and east-Palaearctic (Siberian) species. Several arctoalpine forms were also recorded. Most of these arctic species were not numerous over the area studied and in general, the collembolan assemblages at the coldest sites of the reserve did not differ significantly from those typical of the forest zone, with the exception of two species, Desoria tshernovi and D. inupikella, which often predominated in the karst communities. The origin and appropriateness of the term relict for the revealed “insular” populations of arctic species are discussed.  相似文献   

6.
Epigeic communities of Collembola were studied after a windthrow in differently managed spruce forest stands in the High Tatras, Slovakia. Investigations were carried out in following treatments: reference forest stands (REF), windthrown stands left to natural regeneration (NEX), windthrown stands from which fallen wood had been extracted (EXT), and windthrown stands from which fallen wood had been removed and which had been affected by fire (FIR). A Kruskal-Wallis nonparametric ANOVA revealed significant differences of Collembola community composition and activity between the treatments studied, which was also further supported by the results from NMS ordination and cluster analysis using indicator species analysis. EXT stands had communities with remarkably high activity and diversity of Collembola, whereas FIR stands had low species richness and diversity indices compared to other treatments (REF, NEX, EXT). Windthrown stands had greater collembolan activity and diversity (NEX, EXT) than intact forest stands. However, forest specialists and bryophilous species were sensitive to forest clearing and fire disturbance and were replaced by xeroresistant and generalist species, or species preferring open habitats. The collembolan community most similar to that found in REF stands, in terms of community homogeneity and the magnitude of diversity indices, was found in NEX stands.  相似文献   

7.
Studies of carrion fauna have increased in Brazil and have contributed to the knowledge of this fauna in the national territory. Brazil has continental dimensions and presents various biomes in its territorial area. Most of the carrion fauna have seldom been studied, and this is especially true for the Savanna or “Cerrado.” The present research examined the fauna visiting carrion in two environments and two seasons in a rural area situated in a region of Cerrado in southeastern Brazil. The two environments studied were a pasture and a fragment of semi-deciduous forest. Samples were collected during the dry and humid seasons of the year. The study identified the diversity and relative abundance of species attracted to pig carcasses (Sus scrofa L.) exposed in each environment and season. Eight pig carcasses (10 ± 1 kg) were placed in traps, and adult insects attracted to the traps were collected during the decay of the carcasses. A total of 92,489 insects were collected during the experiments. The Diptera was the most frequent order (92.2%) represented by 27 families and at least 124 species. This was followed by Coleoptera (4.4%) represented by 14 families and at least 65 species. Sarcophagidae had the greatest diversity of species, followed by Muscidae and Calliphoridae. Several species were collected only during a specific period of the year or in a single environment. The results are important from an ecological point of view and for Medico-Legal Forensic Entomology.  相似文献   

8.
The response of species numbers and density of Collembola to manipulation of plant species richness (1, 2, 4, 8, 32 species) and number of plant functional groups (grasses, legumes and non-legume herbs) was studied in an experimental grassland at the Swiss BIODEPTH site (Lupsingen, Switzerland) in October 1997. Plant species richness or number of plant functional groups did not affect total diversity of Collembola, however, the number of Collembola species increased in the presence of legumes and the grass Trisetum flavescens . The abundance of Protaphorura armata increased but that of Hypogastruridae/Neanuridae significantly decreased with increasing number of plant functional groups. Other groups including the herbivorous Symphypleona did not respond to plant species richness and plant functional groups. Possibly, Hypogastruridae/Neanuridae species are weak competitors declining in density if the density of other Collembola groups increase. In general, the effect of the number of plant functional groups on the densities of collembolan taxa was stronger than that of plant species richness. Changes in Collembola density and diversity in part was likely caused by increased soil microbial and fine root biomass in treatments with higher plant functional group diversity. The presence of legumes resulted in an increase in the densities of total Collembola, Symphypleona/Neelipleona and Isotomidae indicating that they benefited from the high litter quality and the increased microbial biomass in the rhizosphere of legumes. The results suggest that microbivorous soil invertebrates are controlled by food quality rather than quantity. Furthermore, they indicate that presence of certain plant species and functional groups may be more important for collembolan community structure than the diversity of plant species and functional groups per se.  相似文献   

9.
Plankton and littoral samples were obtained from several ponds and lagoons of different environments in the Mexican state of Tabasco. These systems are located in the Grijalva-Villahermosa or the Usumacinta basins. Twenty-two copepod species were recorded, most of them cyclopoids with neotropical and Caribbean affinities. Physical and chemical data associated with the species, as well as morphometric parameters of the surveyed systems were measured and analyzed. A correlation was found between diversity and parameters related to the productivity and the shoreline development (D L) of the systems; therefore the littoral heterogeneity could be used to predict the species number in shallow tropical systems. At a regional level, the Tabasco copepod fauna is similar to that known from the Yucatan Peninsula, but different from the faunal associations of central Mexico. Distributional patterns differed slightly between both basins and appear to be correlated with climatic variations. This first survey of the freshwater copepod fauna in the state of Tabasco shows it to be constituted mainly by neotropical forms.  相似文献   

10.
  • 1 Brazil is the second most bat species‐rich country in the world, but the available information on the occurrence and distribution of bat species in Brazil is still heterogeneous and fragmented.
  • 2 We review the occurrence and distribution of bat species in Brazil, analyse the spatial performance of inventories conducted to date and identify knowledge gaps. We also identify the main factors contributing to the recent increase in the knowledge of the Brazilian bat fauna, and make suggestions for maintaining this momentum into the near future.
  • 3 We plotted record coordinates on a map, grouped them in 0.5 degrees of latitude × 0.5 degrees of longitude grid cells, and analysed records for each of the five terrestrial biomes in Brazil, and for the 1439 priority polygons for the conservation of Brazilian biodiversity.
  • 4 We identified 5502 formal bat records in Brazil, indicating that less than 10% of the country is minimally surveyed, and that for nearly 60% of Brazil there is not a single record of bat species. Record coverage varies from 79% in the Atlantic Forest to 24% in Amazonia, but none of the Brazilian biomes is well surveyed for bats. Bat species have been recorded in only 15% of the priority areas for Brazilian biodiversity conservation.
  • 5 If the current rate of recording bats in empty grid cells (10% every 4 years) was maintained, it would take 33 years for all cells to have a single record. If the current rate of recording ≥20 species in a grid cell (0.8% per year) was maintained, it would take 200 years for the bat fauna of Brazil to be minimally surveyed. Alarmingly, most of the data‐poor areas are at the expansion frontiers of the agro‐business, near the surrounding deforestation fronts.
  • 6 We make recommendations for scientific research on bats in Brazil, to ensure the conservation of this ecologically important taxon.
  相似文献   

11.
Three exotic species of Collembola are here identified in collections made during surveys on subantarctic South Georgia in the summers of 2005/2006 and 2009/2010. Previously, only two exotic species of Collembola were known from the island. Increased visitation by tourists, research and maintenance personnel seems an obvious cause despite strict quarantine controls imposed on all visitors. The biology, habitat and distribution of the new species records indicated that fresh vegetables, imported in past years, were their likely means of dispersal to the island. A risk analysis based on their current distribution and ecology was conducted for exotic collembolan species that could invade South Georgia. Pathway analysis of the species with the highest risk scores suggested additional quarantine management protocols could include fumigation of imported fresh food, and this is recommended to minimise the risk of further invasions. A review of exotic Collembola in the Antarctic and subantarctic is provided and the biological traits of Collembola are discussed in relation to their invasion potential.  相似文献   

12.
A soil arthropod community was studied in a dry evergreen forest over a 3-year period from May 1998 to April 2001. Population abundance, species composition, and community structure were investigated over the 3-year study period. The soil arthropods consisted of Acari (75.38%), Collembola (16.11%), and others (8.51%), and their abundances showed a clear difference between the rainy and dry seasons. Population abundance of Collembola and Acari were low during drought conditions. The humidity was the most important factor determining distribution, abundance, and survival of soil Collembola in this tropical forest. High predation and low accumulation of organic matter caused low population abundance of Collembola in the tropical habitat. The collembolan community was dominated by a few dominant species over the study period. The pattern of seasonal changes in numbers of Collembola was similar over the 3-year study period. The species composition of the collembolan community was constant and persistent throughout a 3-year study period. Thus, the collembolan community showed constancy in its species composition with seasonal variability over the 3-year study period.  相似文献   

13.
Biodiversity of Collembola and their functional role in the ecosystem   总被引:1,自引:0,他引:1  
More than 6500 species of Collembola are known from throughout the world and these are only a small part of the still undescribed species. There are many checklists and catalogues of Collembola for smaller territories and entire continents. Biogeographical analyses have been made for some genera and smaller territories. The most serious problems for a global biogeographical analysis is the lack of enough records from immense territories of all continents. Local biodiversity of Collembola can be very high, reaching over 100 species in small mountain ranges. Sampling methods do not impede documenting biodiversity on a global scale. Collembola have well differentiated ecomorphological life-forms and feeding guilds which enable the functional role that Collembola play in ecosystems to be recognised in some degree. Collembola play an important role in plant litter decomposition processes and in forming soil microstructure. They are hosts of many parasitic Protozoa, Nematoda, Trematoda and pathogenic bacteria and in turn are attacked by different predators. They utilise as food Protozoa, Nematoda, Rotatoria, Enchytraeidae, invertebrate carrion, bacteria, fungi, algae, plant litter, live plant tissues, and some plant pathogens. Soil acidification, nitrogen supply, global climate change and intensive farming have greatly impacted collembolan diversity.  相似文献   

14.
Aim The plant diversity of one location on the Guiana Shield, Kaieteur National Park in Guyana, is used to examine the various hypothesized origins of the flora and to evaluate which may best explain the current plant distributions. Location Kaieteur National Park is located on eastern edge of the Potaro Plateau in central Guyana, South America. The species examined have distributions that vary from local to global. Methods The distribution patterns of the families, genera and species known from Kaieteur are examined using generalized distribution patterns. Results Data on distribution patterns, elevation and habitat were gathered from 131 flowering plant families, 517 genera and 1227 species. These plants represent all taxa that are currently known to occur in the area of the original Kaieteur National Park. Families tend to have cosmopolitan or pantropical distribution, genera are mostly neotropical and at the species level, most species are restricted to the Guiana Shield (c. 40%), northern South America (69%) or neotropical (96%) in distribution, each level inclusive of the previous. Conclusions The flora at the study site in Kaieteur National Park has its strongest affinity with the Guiana Shield; 42.1% of the species have a distribution that corresponds with the Shield or is more restricted within the Shield. There is a distinct flora on the Guiana Shield and its affinities lie with the flora of northern South American and beyond that, the neotropics. The flora is not closely affiliated with the floras of the Brazilian Shield, the Amazon, the Andes, the eastern coastal forests of Brazil, southern South America, or Africa as has been previous suggested.  相似文献   

15.
Collembola (springtails) are soil arthropods, representing the most widespread hexapod group worldwide. Being skin-breathing animals, Collembola evolved special cuticular patterns, which are robust and antiadhesive allowing cuticular respiration under humid conditions in the soil environment. Details about function and formation of these unique cuticle characters are still unknown. Here we demonstrate that a high diversity of cuticular structures exists and that the different observed structural patterns of Collembola cuticles might go along with specific adaptations to life in soil. We examined the cuticle structures of 40 different species using scanning electron microscopy and compared the cuticle patterns of the different species with information about their preferred habitat. In addition, we compare the results with current systematic concepts, showing that certain cuticle structures are typical for different collembolan groups.  相似文献   

16.
Due to the spread of Visceral leishmaniasis in Brazilian territory, this research was undertaken with the objective to identify the sandfly fauna and aspects of the species behavior in forest and anthropic environments in Paraná State, Brazil. The sandfly captures were sporadically carried out in 37 municipalities of the Paraná state, during the period from March 2004 to November 2005. Each municipality was once visited, when Falc?o traps were installed during three consecutive nights in forested fragments and anthropic environments; captures with Shannon traps installed in forests and edge of forests, inspection of walls and electric aspiration in domiciles and forested areas were sporadically undertaken. The data analysis was based on estimates of frequency and abundance of the species, by five native landscapes. A total of 38,662 specimens belonging to 23 species were captured. Nyssomyia neivai (Pinto) (75.6%), Ny. whitmani (Antunes & Coutinho) (10.1%), Migonemyia migonei (Fran?a) (7.8%), Expapillata firmatoi (Barreto et al.) (2.1%) and Pintomyia fischeri (Pinto) (1.6%) together constituted 97.2% of the phlebotomine collected. High frequencies of sand flies were found in forests, henhouses, pig-pens and domiciles. The three most frequent species have been implicated in transmission of tegumentary leishmaniasis in Paraná and in the Brazilian Southeastern and Southern Regions. Lutzomyia longipalpis (Lutz & Neiva), the visceral leishmaniasis vector, was not found, however Lutzomyia gaminariai (Cordero et al.), female of which is similar to that of Lu. longipalpis was captured, raising the need to investigate its behavior, including as regard to the vectorial competence.  相似文献   

17.
The drosophilids of a gallery forest in the Brazilian savanna were investigated to identify the temporal and vertical patterns in the community structure of these insects. Twelve monthly collections were performed (December 2007 to November 2008) in three vertical strata of the forest (0, 4 and 8 m heights) using 30 traps baited with fermented banana. The drosophilid assemblage was composed of 61 species (7,623 individuals), experienced temporal fluctuations and was vertically stratified. Both the diversity and abundance of the flies were very low during the dry season, a time when the assemblages were dominated by the exotic species Drosophila simulans, whereas the community showed an increased abundance and richness of neotropical species and showed vertical stratification in the wet season. Rare species were found primarily at the ground level (flies usually associated with neotropical forests) or in the canopy, which harbors species currently associated with open vegetation, little-studied neotropical species and most likely several new species. These changes, which reflect drosophilid adaptations to different environments, involve a shifting of the ecological niches occupied by the flies in the forest over time. This process of change is termed niche construction. Thus, we conclude that this complex and dynamic community structure, which is related to the interaction of several environmental factors associated with different forest environments, contributes to the high diversity of gallery forests in the Brazilian savanna.  相似文献   

18.
Long-term assessments of species assemblages are valuable tools for detecting species ecological preferences and their dispersal tracks, as well as for assessing the possible effects of alien species on native communities. Here we report a 50-year-long study on population dynamics of the four species of land flatworms (Platyhelminthes, Tricladida, Terricola) that have colonized or become extinct in a 70-year-old Atlantic Forest regrowth remnant through the period 1955–2006. On the one hand, the two initially most abundant species, which are native to the study site, Notogynaphallia ernesti and Geoplana multicolor have declined over decades and at present do not exist in the forest remnant. The extinction of these species is most likely related with their preference for open vegetation areas, which presently do not exist in the forest remnant. On the other hand, the neotropical Geoplaninae 1 and the exotic Endeavouria septemlineata were detected in the forest only very recently. The long-term study allowed us to conclude that Geoplaninae 1 was introduced into the study area, although it is only known from the study site. Endeavouria septemlineata, an active predator of the exotic giant African snail, is originally known from Hawaii. This land flatworm species was observed repeatedly in Brazilian anthropogenic areas, and this is the first report of the species in relatively well preserved native forest, which may be evidence of an ongoing adaptive process. Monitoring of its geographic spread and its ecological role would be a good practice for preventing potential damaging effects, since it also feeds on native mollusk fauna, as we observed in lab conditions. Júlio Pedroni: Granted by CNPQ–Brazil.  相似文献   

19.
As biodiversity loss rapidly increases through habitat degradation in the Amazon rainforest, the need to characterize and understand the species diversity becomes even more important. In this study we used empirical and published datasets to assess the diversity patterns and produce the first overview of the sphingid fauna in the Brazilian Amazon. We compared the diversity patterns in distinct areas in the biome by analyzing hawkmoth assemblages considering both species composition and abundance, and asked whether these communities are structured according to environmental factors. Additionally, we provide information of diel activity pattern of sphingids and evaluated the importance of time in sampling effort. We found that the Brazilian Amazon may harbor more than 80 % of the hawkmoth species that occur in Brazil and more than half of the species recorded in South America. Species composition and assemblage structure is determined by the quality of the habitat (disturbed or undisturbed vegetation), temperature and relative humidity. Finally, we show that the temporal activity of sphingids presents distinct patterns at different taxonomic levels, highlighting the importance of full night collections to better characterize the fauna. Our results show that habitat alteration can be an important factor affecting sphingid assemblages, illustrating the importance of Protected Areas in species maintenance.  相似文献   

20.
There is very little information available about Culicoides species (Diptera: Ceratopogonidae) in the western Brazilian Amazon. However, studies of the fauna of this region are essential to knowledge of the species and potential vectors within it. Thus, the present study aims to evaluate the abundance, richness and composition of Culicoides species in rural areas in the state of Rondônia, Brazil. Culicoides specimens were collected in forest and pasture environments in the municipality of Porto Velho, using light traps. A total of 1708 individuals (1136 females and 572 males) belonging to 33 species were collected; 28 of these samples represent new records for the state of Rondônia and include the first record of Culicoides contubernalis in Brazil. Culicoides insignis was the most abundant species (86.1%). Species richness was greater in forest areas (32 species, 96.96%), whereas pastures presented the greatest number of Culicoides captured (n = 1540, 90.1%). This study shows that Culicoides populations differ between forest and pasture environments and indicates that the abundance of C. insignis is an important factor in epidemiological vigilance studies in the region.  相似文献   

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