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1.
The first fossil representative of the jewel damselflies (Calopterygoidea: Chlorocyphidae), a family of large, prominent, and often brilliantly colored Old World tropical Zygoptera, is described and figured. Chlorocypha cordasevae n. sp. was recovered from the Late Miocene (Early Pannonian, Serravalian to Tortonian, c.11 Ma) locality of Paldau, in the Styrian Basin, Austria. The fossil seems to be related to the African genus Chlorocypha Fraser, and within a larger group of African genera also including Stenocypha Dijkstra, Africocypha Pinhey, and Platycypha Fraser, and collectively set apart from southern Asiatic genera. The discovery of a central European species of Chlorocypha as recently as the Late Miocene reveals a much wider range to the family than its generally disjunctive modern distribution, demonstrating a Neogene contraction to their range, likely in connection with climatic cooling, drying, and developing seasonality. Modern chlorocyphids live under warm, humid climates, and the presence of C. cordasevae in the Pannonian fauna of Paldau further corroborates such a subtropical paleoclimate for the locality at that time. 相似文献
2.
《Plant Ecology & Diversity》2013,6(3):373-385
Background: Climatic variables determining the most suitable sites for the woodlands of Tierra del Fuego are not yet as well understood as those related to their geographical range. Aim: The aim of this paper is to provide some insights into the relationships between climatic niche and current distribution of three Nothofagus species in Tierra del Fuego. Methods: We have identified the climatic variables responsible for the most suitable sites for three sub-Antarctic Nothofagus woodland types within their climatic ranges by calculating suitability indices, using the CLIMPAIR niche-based phytoclimatic model. Results: The distribution range of the major Nothofagus woodlands is mainly driven by variables related to water stress, whereas phytoclimatic suitability is mainly driven by thermal variables related to warm summer temperatures for Nothofagus betuloides and N. pumilio and to winter cold for N. antarctica that are also mainly responsible for the peculiarity of the Fueguian climate. Conclusions: These findings introduce a new perspective in the study of the Nothofagus ecology, based on the climatic traits responsible for the high-suitability locations instead of the traditional focus on the overall geographical distribution. 相似文献
3.
《Cytotherapy》2021,23(11):1029-1035
Background aimsUmbilical cord blood is an established source of stem cells in patients with hematologic malignancies who do not have HLA-compatible matched related or unrelated donors. The success of an umbilical cord blood transplant depends on the dose of total nucleated and CD34+ cells infused. Therefore, collecting, banking and listing high-quality cord blood units with high total nucleated and CD34+ cell dose are essential.MethodsHere the authors describe their cord blood bank's novel collection technique, which involves both in utero and ex utero collection of a single cord blood unit. The authors also evaluated maternal, neonatal and collection parameters that may impact the cell dose.ResultsMaternal gestational age and race, and neonatal weight and sex correlated with the total nucleated cell dose.ConclusionsThe optimized collection of umbilical cord blood is critical for its use as a source of stem cells for transplantation. 相似文献
4.
Adwan H. Shehab Osama Mouhra Mohammad A. Abu Baker Zuhair S. Amr 《Zoology in the Middle East.》2013,59(1):4-12
Abstract A new distribution locality for the Forest Dormouse, Dryomys nitedula, is reported from Ashrafiat Al Wade in the Barada River valley, northwest of Damascus. The specimens are morphologically similar to the Arabian and Turkish populations. Some ecological and biological aspects are discussed. 相似文献
5.
《Plains anthropologist》2013,58(95):37-56
AbstractIn 1976 Alfred E. Johnson proposed a subsistencesettlement model for Kansas City Hopewell. The model consisted of a subsistence territory encompassirig a drainage upon which a large permanent village settlement was located near its mouth with a series of smaller specialized ancillary sites located up from the village. Limited corn and squash horticulture would be present in the latter half of the occupation too. A test of such a model would be actual limited activity sites. The Yeo site, a late kansas City Hopewell site, is a hickory nut/marsh elder seed collection/storage station. It is exactly the type of site necessary to substantiate such a model. Also, such a test implies the testing of the notion that there are “specialized, limited activity sites,” sites which are important to some of the suppositions of the New Archaeology. Additionally, the presence of the combination of hickory/cultivated marsh elder (Iva annua var. macrocarpa) utilization within the context of an upland oak-history forest may be interpreted as supporting Asch and Asch’s (1978) model of marsh elder domestication. 相似文献
6.
《Journal of bryology》2013,35(3):485-486
AbstractThe hepatic Nardia insecta Lindb. is reported from a streamside locality in the Kielder district of South Northumberland, new to Britain. It was first collected in 1964 when herbarium specimens were initially referred to N. geoscyphus. Plants of N. insecta were refound in 1993 at the same locality where it has persisted while conifer plantations have developed in the surrounding catchment. N. insecta from Northumberland is described and illustrated, and a chromosome count of n = 18 is reported. It is compared with N. geoscyphus which has been found to be represented in the British Isles by two forms that differ in morphology and geographical distribution. 相似文献
7.
AimFormerly introduced for their presumed value in controlling mosquito‐borne diseases, the two mosquitofish Gambusia affinis and G. holbrooki (Poeciliidae) are now among the world''s most widespread invasive alien species, negatively impacting aquatic ecosystems around the world. These inconspicuous freshwater fish are, once their presence is noticed, difficult to eradicate. It is, therefore, of utmost importance to assess their geographic potential and to identify their likely ability to persist under novel climatic conditions.LocationGlobal.MethodsWe build species distribution models using occurrence data from the native and introduced distribution ranges to identify putative niche shifts and further ascertain the areas climatically suitable for the establishment and possible spread of mosquitofish.ResultsWe found significant niche expansions into climatic regions outside their natural climatic conditions, emphasizing the importance of integrating climatic niches of both native and invasive ranges into projections. In particular, there was a marked shift toward tropical regions in Asia and a clear niche shift of European G. holbrooki. This ecological flexibility partly explains the massive success of the two species, and substantially increases the risk for further range expansion. We also showed that the potential for additional expansion resulting from climate change is enormous—especially in Europe.Main conclusionsDespite the successful invasion history and ongoing range expansions, many countries still lack proper preventive measures. Thus, we urge policy makers to carefully evaluate the risk both mosquitofish pose to a particular area and to initiate appropriate management strategies. 相似文献
8.
AbstractWe report here finds of thalattosuchians from Western Carpathians. The material consists of two isolated teeth from two different localities of the Pieniny Klippen Belt. The material represents the first evidence of the occurrence of both clades Teleosauridae and Metriorhynchidae in Slovakia. The first, a small tooth comes from the locality Beňatina and is dated early Middle Jurassic (Aalenian). Identification of the specimen shows it belongs to a longirostrine teleosaurid, possibly to Steneosaurus. Teleosaurids were largely restricted to lagoonal/near-shore environments. Their limbs allow them to support and walk on land. Regarding that fact, the presence of this taxon in Beňatina might be an indication of terrestrial land in the nearby area and shows a location of epicontinental seaways. A second larger tooth was found in the Upper Jurassic (Tithonian) sediments of the locality Kyjov, and is tentatively allocated in the genus Plesiosuchus. The members of Plesiosuchina are known in England, France, Portugal and Sicily. Our findings indicate a much wider spatial distribution of this clade in Europe and it fits well with the previous interpretation of sediments of the locality Kyjov as deep-water pelagic deposits. 相似文献
9.
Abstract Opportunistic sightings and strandings of Caperea marginata (n=196) from the vicinity of Australia and New Zealand (1884 to early 2007) were used to relate geographic and temporal patterns to oceanographic and broad-scale climatic variability. Records were not uniformly distributed along the coast and more (69%) were from Australia than New Zealand. Seven coastal whale ‘hotspots’ were identified which accounted for 61% of records with locality data. Half of the hotspot records were from southeast (37) and northwest (20) Tasmania—others each had 9–15 events. Upwelling and/or high zooplankton abundance has been documented near all whale hotspots. Records of C. marginata occurred in all months, with 75% in spring and summer. Inter-annual variability showed broad agreement between increased whale records (usually in spring/summer) and strongly positive ‘Niño 3.4’ during 1980–1995 but not thereafter. Coastal upwelling and productivity increase during climatic phenomena such as El Niño and are likely to be quickly beneficial to plankton-feeding whales such as C. marginata. 相似文献
10.
Thomas W. Fieldsend Nicolas Dubos Kenneth L. Krysko Christopher J. Raxworthy Sparkle L. Malone 《Ecology and evolution》2021,11(14):9410
AimTo investigate whether the frequently advocated climate‐matching species distribution modeling approach could predict the well‐characterized colonization of Florida by the Madagascar giant day gecko Phelsuma grandis.LocationMadagascar and Florida, USA.MethodsTo determine the climatic conditions associated with the native range of P. grandis, we used native‐range presence‐only records and Bioclim climatic data to build a Maxent species distribution model and projected the climatic thresholds of the native range onto Florida. We then built an analogous model using Florida presence‐only data and projected it onto Madagascar. We constructed a third model using native‐range presences for both P. grandis and the closely related parapatric species P. kochi.ResultsDespite performing well within the native range, our Madagascar Bioclim model failed to identify suitable climatic habitat currently occupied by P. grandis in Florida. The model constructed using Florida presences also failed to reflect the distribution in Madagascar by overpredicting distribution, especially in western areas occupied by P. kochi. The model built using the combined P. kochi/P. grandis dataset modestly improved the prediction of the range of P. grandis in Florida, thereby implying competitive exclusion of P. grandis by P. kochi from habitat within the former''s fundamental niche. These findings thus suggest ecological release of P. grandis in Florida. However, because ecological release cannot fully explain the divergent occupied niches of P. grandis in Madagascar versus Florida, our findings also demonstrate some degree of in situ adaptation in Florida.Main conclusionsOur models suggest that the discrepancy between the predicted and observed range of P. grandis in Florida is attributable to either in situ adaptation by P. grandis within Florida, or a combination of such in situ adaptation and competition with P. kochi in Madagascar. Our study demonstrates that climate‐matching species distribution models can severely underpredict the establishment risk posed by non‐native herpetofauna. 相似文献
11.
《Plant Ecology & Diversity》2013,6(2-3):105-113
Background: Seed mass is a life history trait that is related to invasiveness. Under limiting conditions, a trade-off is observed whereby an increase in seed mass occurs at the expense of seed numbers; if the above trade-off holds across climatic gradients it can provide an opportunity to assess the fitness/invasive potential of exotic plants.Aims: To examine the variation in the life history traits of Eschscholzia californica populations across climatic gradients and to relate these traits to observed invasiveness.Methods: We examined 19 populations in Chile. For each population we related seed mass, seed number, the slope of trade-off between seed mass and number and plant density with annual precipitation and mean annual temperature.Results: Seed number and the coefficient of variation in seed mass were positively correlated with climatic variables. Trade-off was detected in 26% of the populations and no relationship was detected with climatic gradient. Plant density was negatively associated with precipitation.Conclusions: The results suggest that for E. californica producing seeds with a variety of sizes is an optimal strategy to face geographic heterogeneity and hence to increase its invasiveness. Increased production of seeds at the cool and wet southern limit of the current range of the species does not contribute to an increase in its invasiveness. 相似文献
12.
The monotypic genus Evanos (Coleoptera: Rutelidae: Geniatini) is revised and a new species, E. danieleae Grossi, n. sp., is described based on specimens collected from Minas Gerais, Brazil. A lectotype is designated for Evanos villatus. Diagnostic characters and comments about the taxonomic status of the genus are given, as well as a key for both species and a distribution map with the known locality records. 相似文献
13.
《Plains anthropologist》2013,58(22):249-256
AbstractThe Swift Bird House (39DW233) is a prehistoric structure of indeterminate characteristics. The associated artifacts are directed to a Northern Plains horticulture and hunting complex. A tenuous relationship to the Anoka Focus and a possible occupation date of about A. D. 1500 is suggested for the site 相似文献
14.
《Plant Ecology & Diversity》2013,6(4):529-540
Background: All human land use (LU) affects the distribution of plant species; however, the impacts vary with the type/intensity of LU. For managing ecosystems, it is therefore essential to understand the effects of LU types on the distribution of plant species on a macroscale.Aims: The objectives of our study were to quantify the effects of various LU types on the distribution of vascular plant species in Japan and to determine in particular the extent to which LU was an important factor for the distribution of common species.Methods: Based on a logistic regression model and variation partitioning being applied to each plant species, we evaluated the partial deviance by six LU types, four climatic types and three topographic and geological factors for 647 plant species at 14,412 sites in Japan.Results: The effect of LU was significant for species present at multiple sites. Of the six LU types, secondary vegetation and plantation were the most important factors determining species distribution for many species.Conclusions: Our results suggest that distribution of the common species is largely affected by LU on macroscale. The design of LU relating to secondary vegetation and plantations will thus be important in determining changes in the vegetation composition within Japan. 相似文献
15.
《Plant Ecology & Diversity》2013,6(2-3):197-215
Background: Temporary ponds, an abundant habitat in the Maghreb region and notably in Morocco, have a high conservation value. However, they are mainly known from the north of the country.Aims: The aim of this work was to characterise the vegetation of Moroccan temporary ponds along a combined gradient of latitude and anthropogenic pressure.Methods: Eighty-five ponds distributed along a north–south gradient of 750 km were sampled. For each pond, all vegetation was surveyed (flooded and dry parts) and the local abiotic characteristics were measured during two successive hydrological cycles. The prevailing anthropogenic pressures were also identified and were attributed an impact score.Results: Eighty-one characteristic pond species (including 17 rare species) were recorded, with several new distribution data in the southern part of the latitudinal gradient. Plant communities were related to climatic and anthropogenic factors, but mostly to local factors, such as maximum water depth and soil pH. The northern ponds (wettest macroclimate) were rich in characteristic species and rare species, while the southern (driest macroclimate) ponds were more species poor.Conclusions: In addition to the direct impact of increasing human activity, a further reduction of the floristic richness of temporary ponds is expected due to climatic changes. This is particularly the case for characteristic species which have a high conservation value. 相似文献
16.
【背景】北美刺龙葵是一种全球广泛分布的恶性杂草,已被列入我国进境检疫性有害生物名单。近年来北美刺龙葵不断随进口货物传入我国,明确其传入途径和适生区对控制其入侵具有重要意义。【方法】采用GIS、空间统计学、Maxent生态位模型等方法分析了北美刺龙葵的传入途径与潜在分布区,并通过ROC分析法对模型进行检验。【结果】跨区域农产品贸易是北美刺龙葵全球扩散的驱动力与传入我国的主要途径。生态模型预测结果表明,北美刺龙葵在我国具有广阔的适生区,除黑龙江、吉林、内蒙古、青海、甘肃、西藏、四川西北部以外的区域都是其在我国的适生区,其中高风险区主要集中在东部和南部沿海、西南边境和新疆的部分地区。AUC值为0.789,表明本研究建立的Maxent模型的预测能力较强,能够很好地拟合物种已知分布的环境生态位。【结论与意义】北美刺龙葵在我国的传入风险极高。基于北美刺龙葵在我国的主要传入途径与潜在扩散媒介的时空分布,划定了重点监测的区域,建议对适生区内极易传入的高风险区如港口、机场、物流中转站、加工厂等开展早期监测预警,以预防其再次入侵与进一步扩散蔓延。 相似文献
17.
Diversity of Antarctic terrestrial protozoa 总被引:6,自引:0,他引:6
H. G. Smith 《Biodiversity and Conservation》1996,5(11):1379-1394
Heterotrophic protozoa have a global distribution in terrestrial habitats. The functional groups significantly represented are zooflagellates, cillates, gymnamoebae and testate amoebae. Their range extends into the Antarctic zone, but the species richness of the communities is rarely of the same order of magnitude as those in temperate latitudes. Species diversity is usually very low owing to dominance of the communities by single, or a few, species which are best adapted to the Antarctic terrestrial environment. This is characterized by seasonal, diurnal or unpredictable fluctuations in moisture, temperature and bacterial food supply of high amplitude. The fauna shows pauperization with latitude and climatic severity. Nearly all records of species distribution are consistent with the model that community composition is determined by local conditions. An important exception is the distribution of the testate amoeba genus Nebela whose species distribution is influenced by biogeographical factors. Successional changes in community composition in fellfield habitats are characterized by the sequence: pioneer microflagellate colonizers, larger flagellates and small ciliates, and finally testate amoebae. The succession is most closely correlated with the accumulation of organic matter. A model of the strategies of dominant microflagellate species can be constructed by ordinating them on a two-dimensional habitat template of A-r-K selection continuum. The globally ubiquitous microflagellate Heteromita globosa emerges as the most strongly A-selected and K-selected. The occurrence of terrestrial protozoa near their latitudinal limits of distribution can serve as sensitive indicators of the biological effects of climatic change. Having short generation times and effective means of cyst dispersal, changes in the gross distribution can provide rapid warning of critical changes in thermal regimes. 相似文献
18.
Andreja Radović Vassiliki Kati Melita Perčec Tadić Damijan Denac Dražen Kotrošan 《Bird Study》2013,60(1):106-114
Capsule Spatial environmental modelling well predicted nesting distribution of the White stork in Southeast Europe and can be used in conservation planning with respect to climate change.Aims To create spatial models for predicting White Stork presence and densities in the Southeast Europe to identify areas of suitable habitat for White Storks.Methods We quantified the habitat used by nesting White storks in Southeast Europe. Using spatial modelling, we defined a set of free and available online environmental variables that predict the breeding localities of the species. We employed pseudo-absences and the kriging of the residuals in order to create predictive models of nest presence and density.Results The presence–absence model was found to be precise in predicting the presence of nests. Both density and presence of breeding pairs were best explained negatively by elevation, slope, minimum temperature during May, and distance to the nearest human settlement and positively by topographic wetness index, total area of human settlement and spring precipitation.Conclusion Our robust and easily repeatable models offer a conservation tool to reveal suitable but unoccupied localities for breeding White Storks pairs which may inform our understanding of how climate change might affect the species' distribution in the future. For example, protecting White Storks on the Dalmatian coast may become even more significant in the future, because the Dalmatian coast is predicted as the only suitable breeding area in Croatia later this century. 相似文献
19.
《Journal of bryology》2013,35(4):305-309
AbstractThe discovery of Paludella squarrosa (Hedw.) Brid., new to Ireland, is reported. This Boreo-arctic Montane species has a relic distribution in western and central Europe and was formerly more widespread. The reasons for its decline and its documented extinction from Britain and the Netherlands in recent times are discussed. The vegetation and ecology of the Irish locality are described. The associated species include Leiocolea rutheana, another Boreal relic species and a second record for Ireland. 相似文献
20.
《Plant Ecology & Diversity》2013,6(3):349-354
ABSTRACTBackground: Climate change may increase the risk of biological invasions. However, current knowledge of this interaction is limited.Aims: We aimed to quantify (1) the effect of climate change on the potential distribution of invasive plant species in Spain, (2) the importance of the area of origin of such species and (3) the vulnerability of different biogeographic provinces to future changes in climatic suitability for invaders.Methods: We applied six methods of species distribution modelling to assess the variation of climatically suitable areas for 40 alien plants. We developed a Potential Area Change Index and used it as the response variable in modelling for three future emissions scenarios and three global circulation models over three time periods. The area of origin and biogeographic province in Spain were also considered.Results: We found a highly specific response for each plant species rather than a clear trend for the entire set of species. Predicted climate suitability increased over higher emission scenarios and longer projected time lags. Neotropical species showed the greatest potential climatic range expansion. We detected a strong interaction between the geographic origin of a species and the biogeographic province.Conclusions: Special attention should be given to the areas where aridification of climate is projected and where introduced neotropical species are likely to expand their range. Future work should develop accurate species-specific approaches that allow the management invasive plant species. 相似文献