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1.
Abstract

New or interesting plants in the mountainous basin of the Esino (Marche region).—The Authors point out a discovery of 46 species of remarkable importance concerning the flora of the Marche region in the mountainous basin of the Esino. Among these, Poa chaixi and Monotropa hypopithis have been discovered in this region for the first time.  相似文献   

2.
Abstract

A sample of Ischnura-specimens from the Nahr al-Khabur drainage basin in Mesopotamia contained a single aberrant male which could not be assigned to any of the species occurring in the area. Several morphological characters of this specimen were found to be intermediate between the sympatric Ischnura elegans ebneri and Ischnura fountainei. and it is regarded as a hybrid of these species. Ischnura intermedia is reported for the first time from Syria.  相似文献   

3.
Aristolochia dalyi, from western Peruvian and Brazilian Amazonia, andA. bahiensis, from Bahia, Brazil, are described and illustrated. The species belong toAristolochia ser.Thyrsicae andA. ser.Hexandrae subser.Anthocaulicae, respectively. A key to the eight western Amazonian species of the seriesThyrsicae is presented.Aristolochia dalyi closely resemblesA. silvatica Barb. Rodr. from the Río Negro basin, andA. bahiensis—the first cauliflorous species ofAristolochia known from the Mata Atlantica—is similar toA. guentheri O. C. Schmidt andA. klugii O. C. Schmidt, from the Western Amazon basin. Characters based primarily on the perianth shape, along with some vegetative features, are used to distinguish the two newly described species from their close relatives.
Resumen   Aristolochia dalyi, del occidente de la amazonía peruana y brasilera, yA. bahiensis, del estado de Acre, en Brasil, son descritas e ilustradas. Las especies pertenecen aAristolochia ser.Thyrsicae yA. ser.Hexandrae subser.Anthocaulicae respectivamente.Aristolochia dalyi es incluída en una clave para diferenciarla de las especies de la serieThyrsicae presentes en la Amazonía occidental, y resulta ser similar aA. silvatica Barb. Rodr, propia de la cuenca del río Negro; por su parte,A. bahiensis, hasta ahora la única especie deAristolochia cauliflora hallada en la Mata Atlántica, es similar aA. guentheri O. C. Schmidt yA. klugii O. C. Schmidt, propias del occidente de la cuenca amazónica. Los caracteres diagnósticos de las nuevas especies se basan principlalmente en la forma del perianto, aunque algunas diferencias vegetativas son también reconocidas.
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4.
Abstract

The composition of the freshwater mollusc fauna from Lake Sapanca (Marmara region, NW Turkey) is described. The occurrence of Sadleriana fluminensis (Hydrobiidae) is a new record for Turkey. The origin of several species from the former catchment basin of the Lower Danube (the “Dardanelles River”) is discussed.  相似文献   

5.
Abstract

The presence of Didymosphenia geminata (Lyngbye) M. Schmidt (Bacillariophyta) was revealed in the Drava river and in its affluent Rio Sesto, both flowing in the Alto Adige/Südtirol region of Italy and belonging to the Danube basin. New data are given on the distribution of the species in the Danube basin.  相似文献   

6.
湿度盐度pH协同驱动锡林河景观疣微菌群空间异质性   总被引:4,自引:0,他引:4  
[目的] 为了阐明锡林河不同景观要素间疣微菌群的空间分布异质性及环境驱动力。[方法] 本文基于生境及微地形差异选择水生的河床中心、河床边缘与牛轭湖床,湿生的低河漫滩与高河漫滩,旱生的低阶地与高阶地等景观要素,基于16S rRNA基因高通量测序技术研究不同景观要素土壤疣微菌群的景观异质性,结合土壤湿度等环境变量研究其驱动力。[结果] 景观要素内疣微菌群呈协同的分布特征,景观要素间呈趋异的分布特征。斯巴达杆菌纲的Chthoniobacter成员及疣微菌纲的突柄杆菌属等成员主要分布在水生河床中心,与砂粒含量存在显著正相关关系(P<0.05);丰祐菌纲成员主要分布在湿生河漫滩,与pH存在正相关关系(P<0.05或P>0.05);斯巴达杆菌纲的DA101_soil_group成员主要分布在旱生河流阶地,与盐度及养分含量等存在极显著正相关关系(P<0.01)。双组与三组环境变量的变异权重分析表明,湿度、盐度、pH对疣微菌群景观异质性的解释度分别高达24.7%与21.4%、24.3%与22.7%、23.1%与20.8%。[结论] 锡林河流域疣微菌群存在景观异质性。Chthoniobacter和突柄杆菌属等成员是河床中心景观要素的指示生物,DA101_soil_group是阶地景观要素的指示生物。湿度、盐度、pH协同驱动疣微菌群的景观异质性。  相似文献   

7.
New species Nummulites vetustufabianiin. sp. is described from the El Hamra Formation, Gara El Hamra section Bahariya Oasis Western Desert. The biometrical measurements include maximum and minimum diameter of the successive radii and heights of whorls, length/height ratio, number of chambers and the marginal cord thickness of each whorl for the megalospheric generation as well as the diameter of proloculus were elaborated to differentiate between some allied granulated species such as Nummulites depressus, Nummulites decrouezae, Nummulites cuvillieri and N. vetustufabianiin. sp.Nummulites fabianii group has lateral distribution for the entire Tethys basin, hence such biometrical studies are needed to emphasise the polyphyletic nature of the group.  相似文献   

8.
Abstract

Bowl-shaped structures are for the first time reported from the Greek Island of Rhodes. They occur in Pleistocene deposits of the Cape Arkhangelos Formation in the Rhodes Synthem. The regularity of their three-dimensional appearance is the argument for a biological origin. This gives the reason to assign the structures to Piscichnus waitemata for which we issue a formal diagnosis. They were formed on a clastic carbonate wedge that built into a coastal, steep-sided basin. Associate trace fossils are Thalassinoides suevicus and Bichordites monastiriensis.  相似文献   

9.
The present paper describes and illustrates the new speciesAverrhoidium dalyi and provides a key to the species ofAverrhoidium. The new species is known from lowland, terra firme forest in the Purus River basin, in Acre, Brazil, and from Manu National Park in Madre de Dios, Peru.
Resumen  En el presente artículo se describe, discute e ilustra la nueva especieAverrhoidium dalyi coleccionada en la cuenca del Río Purus en el estado de Acre, Brasil y en el Parque Nacional del Manu en el departamento Madre de Dios, Peru. También en el presente se provee una clave para las especies deAverrhoidium.
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10.
内蒙古自治区二连盆地、海拉尔盆地是我国重要的煤层气产区,其中生物成因煤层气是煤层气的重要来源,但复杂物质转化产甲烷相关微生物群落结构及功能尚不清楚。【目的】研究煤层水中的微生物代谢挥发性脂肪酸产甲烷的生理特征及群落特征。【方法】以内蒙古自治区二连盆地和海拉尔盆地的四口煤层气井水作为接种物,分别添加乙酸钠、丙酸钠和丁酸钠厌氧培养;定期监测挥发性脂肪酸降解过程中甲烷和底物的变化趋势,应用高通量测序技术,分析原始煤层气井水及稳定期产甲烷菌液的微生物群落结构。【结果】除海拉尔盆地H303煤层气井微生物不能代谢丙酸外,其他样品均具备代谢乙酸、丙酸和丁酸产生甲烷的能力,其生理生态参数存在显著差异,产甲烷延滞期依次是乙酸<丁酸<丙酸;最大比产甲烷速率和底物转化效率依次是丙酸<乙酸<丁酸。富集培养后,古菌群落结构与煤层气井水的来源显著相关,二连盆地优势古菌为氢营养型产甲烷古菌Methanocalculus (相对丰度13.5%–63.4%)和复合营养型产甲烷古菌Methanosarcina (7.9%–51.3%),海拉尔盆地的优势古菌为氢营养型产甲烷古菌Methanobact...  相似文献   

11.
Abstract

A report is presented on freshwater animals collected in 1993 in the Sefid Rud catchment area and the basin of Anzali (Gilan, Iran). Some species are recorded for the first time for Iran. There is a considerable number of species of North American origin (neophytes, neozoans), e.g. Gambusia holbrooki, Rhithropanopeus harrisii, and Azolla sp.  相似文献   

12.
Two new species of the Empis (Leptempis) rustica group are described: E. (L.) tenuis n. sp. and E. (L.) lauriauti n. sp. Both were mainly collected in mountainous areas of the Mediterranean basin; the first species was collected in Morocco and Southern Spain; the latter was found in late summer in the Southern Alps in France. The key to species of the Empis (L.) rustica group is updated to include these two new species as well as a recently described Caucasian species.  相似文献   

13.
Abstract

A review of the distribution of toxic dinoflagellates and related toxic events in the Mediterranean Sea is provided. Diarrhetic shellfish poisoning (DSP) and paralytic shellfish poisoning (PSP) are the main seafood contaminations, that have been reported since 1987. In 1994 four lethal cases for PSP were reported in Morocco. DSP seems to be restricted in the Northern part of the basin, while PSP contamination presents a wider distribution. Potentially DSP species, belonging to the genus Dinophysis, are widely distributed in the Mediterranean Sea, suggesting a wider extension of this contamination. The lack of monitoring programs in the Southern Mediterranean could be responsible of DSP overlooking. The species responsible for PSP are Gymnodinium catenatum in the Alboran Sea and Alexandrium minutum in various parts of the basin. Ichtyotoxic effects, due to Gymnodinium and Gyrodinium species, have been sporadically reported in some Mediterranean areas.  相似文献   

14.
Eigenmannia trilineata López and Castello, 1966 (Sternopygidae) was described from the Río de La Plata basin and subsequently cited from most South American river basins. Questions about the limits of this species raise the possibility of the occurrence of undescribed species misidentified as E. trilineata. Herein we propose the Eigenmannia trilineata species group for species that share the presence of the superior medial stripe on the flank. This group comprises: E igenmannia antonioi sp. nov. , from the Rio Anapu, Rio Amazonas basin; E igenmannia desantanai sp. nov. , from the Rio Cuiabá, Rio Paraguay basin; E igenmannia guairaca sp. nov. , from the Riacho Água do Ó, upper Rio Paraná basin; E igenmannia matintapereira sp. nov. , from the Rio Uneiuxi and Rio Urubaxi, Rio Negro basin; Eigenmannia microstoma (Reinhardt, 1852), from the Rio São Francisco basin; E igenmannia muirapinima sp. nov. , from small tributaries of the Rio Amazonas; E igenmannia pavulagem sp. nov. , from the tributaries of Rio Capim, Rio Guamá basin; E. trilineata, from the lower Rio Paraná basin and Río de La Plata basin; Eigenmannia vicentespelaea Triques, 1996, from São Vicente I and II caves, Rio Tocantins basin; and E igenmannia waiwai sp. nov. , from the Rio Trombetas basin. These species can be distinguished from each other by unique sets of meristics, morphometrics, osteological and colour pattern features. © 2015 The Linnean Society of London  相似文献   

15.
黄雅丹  付灿  李强 《微生物学报》2024,64(6):2057-2070
存在于健康植物根中的内生细菌不但能够与宿主植物建立共生关系,而且还具有促进植物生长、提升植物对营养元素摄取能力等功能,从而对维持陆地生态平衡、提升喀斯特石漠化综合治理成效具有重要的意义。【目的】探究宿主植物根中的内生细菌群落结构,为深入认识宿主植物-内生细菌的互作机制提供理论依据。【方法】以被引种到喀斯特断陷盆地石漠化综合治理区不同种植年限钙果根中的内生细菌和根际土为研究对象,分析根内生细菌群落特征和根际土理化性质。【结果】钙果种植年限对研究区土壤质量整体有着直接、显著的影响,并间接影响根内生细菌群落。根内生细菌群落以共生互作为主,通过共网络结构识别出种植第一年和第三年的前三位优势属为链霉菌属(Streptomyces)、卡氏伯克霍尔德菌属(Burkholderia-Caballeronia- Paraburkholderia)和噬几丁质菌属(Chitinophaga),种植第五年的前三位优势属为StreptomycesChitinophaga和海无柄孢囊黏细菌属(Haliangium)。根内生细菌群落的形成主要由随机性过程中的生态漂变所主导。【结论】不同生长阶段钙果根内生细菌群落结构的差异是由于随机性过程赋予了微生物物种多样化。内生细菌群落的共生互作关系以及优势菌具有生防功能,可增强钙果定殖能力和生长,进而提升钙果在喀斯特断陷盆地石漠化综合治理区的生态效益和经济效益。  相似文献   

16.
Marina victoriae andM. brevis are newly described species from the southern Baja California peninsula, Mexico. The former is a perennial herb locally abundant in the eroded hillsides at the foothills of Sierra de la Victoria, where an oak woodland and a dry tropical forest meet. The latter is an elusive ephemeral inhabiting a narrow strip of land between the mangroves and the desert scrub on an island in the Gulf of California. These two new species belong to the seriesChrysorrhizae, a group native to the Gulf of California basin.  相似文献   

17.
Abstract

Account on the Cartography of the Vegetation of the Basin of Bormio (Valtellina). Presentation of the phytosociological Map 1:5000. — The authors illustrate the features of the new phytosociological map of the basin of Bormio (Valtellina). The chief types of vegetation of the region are outlined.  相似文献   

18.
Pinus georginae is described and illustrated as a new endemic species from the valleys in the southern basin of Río Ameca, Jalisco, western Mexico. It is closely related to Pinus praetermissa; however, after studying the cones and anatomy of the leaves in detail, characteristics were revealed that identify P. georginae as a distinct species.
Resumen  Se describe e ilustra Pinus georginae como una especie nueva, endémica de algunos valles intermontanos al sur del Río Ameca, Jalisco, en el Occidente de México. Los árboles se parecen a Pinus praetermissa; sin embargo, al estudiar con detalle los conos y la anatomía de las acículas lo ubican a Pinus georginae como una entidad biológica con categoría específica independiente.
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19.
《Plant Ecology & Diversity》2013,6(2-3):241-251
Background: Phragmites australis dieback syndrome, recently reported for the Mediterranean basin, features several symptomatic traits among which the clumping habit seems to be one of the most diagnostic.

Aims: We evaluated the effect of water depth on the intensity of the clumping habit and evaluated the diagnostic role of other traits.

Methods: We investigated patterns of macro-morphological (culm height and diameter, flowering head and dead apical bud rates) and demographic (density) traits of P. australis in function of submersion (PF-permanent vs. NF-temporary) at five Italian wetland sites. We related the occurrence of clumping and its frequency with water depth.

Results: There were clear trends, modulated by site-specific effects, for most of the considered traits in function of the duration of submersion. The clumping rate was close to zero in NF-stands, reached high values in PF-stands and was positively correlated with water depth.

Conclusions: We have shown that permanent submersion with deep water levels plays a crucial role in the occurrence of reed dieback. As all other considered traits, with the exception of the occurrence of dead apical buds, well correlate with the clumping habit, we propose using clumping as a key indicator for detecting potential reed dieback.  相似文献   

20.
【目的】为了探索河流水体污染胁迫对浮游细菌群落的影响。【方法】本研究使用主成分分析将水体污染胁迫分为高、中、低3级,基于高通量测序技术分析了鄱阳湖流域锦江干流浮游细菌群落的多样性、组成以及交互作用。【结果】锦江污染胁迫下的浮游细菌群落优势菌群包括假单胞菌门(Pseudomonadota,13.53%–45.83%)、放线菌门(Actinobacteriota,17.05%–40.50%)、拟杆菌门(Bacteroidota,5.79%–31.56%)、蓝藻菌门(Cyanobacteria,0.41%–59.31%)和芽孢杆菌门(Bacillota,0.11%–4.81%)。其中Bacillota在污染胁迫等级下显著差异(P=0.03)。浮游细菌群落组成在不同水体污染胁迫等级下存在显著差异(P=0.046)。群落丰富度Chao1与ACE指数在低污染胁迫地区显著高于中污染胁迫地区(P=0.024和0.037),Shannon多样性指数差异不显著。共生网络拓扑特征表明,随着水体污染胁迫减小,细菌共生网络的复杂性与稳定性增强,浮游细菌群落之间的交互作用增强。【结论】污染胁迫显著改变了水体细菌群...  相似文献   

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