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1.
武汉东湖南部湖汊的鼓藻类 总被引:6,自引:0,他引:6
从1963年9月到1964年12月,作者在武汉东湖南部的湖汊定点采得48号藻类标本,其鼓藻类十分丰富,经鉴定共有20个属,164个种,75个变种和13个变型。其中有2个新种、7个新变种和2个新变型,12个种、25个变种和5个变型是中国的新记录;在四季中出现频率较高的优势种类有11个种和1个变种。在不同季节共6次所采得的鼓藻种类的统计结果得出,在夏季(6月、8月)的种类最多,秋季和冬季(9月、10月、12月)次之,春季(4月)最少。在东湖252个鼓藻类的分类单位中,热带、亚热带类群共有45个,其中的19个是南亚和东南亚地区特有或普遍分布的类群,13个是以广西为模式产地的类群,从而反映武汉地区鼓藻类区系具有亚热带类型的特点,并与南亚和东南亚的鼓藻类区系关系密切。 相似文献
2.
About one hundred genera with more than 300 species have been identified in water samples, net haul material, periphyton samples from artificial substrate, and benthos and sediment samples collected during 1969–1972. More than 40 taxa of lower rank (subspecies, varieties, forms) were recorded. The most prominent algal groups were diatoms with 138 taxa, and green algae with 122 taxa of which the majority was desmids. The material from the epipelic and epilithic communities in the lake is very scarce, while the list of plankton species is relatively complete, with the exception that a large number of small flagellates could not be identified to species level. The taxa which were identified, are presented in a list with additional notes on occurrence. 相似文献
3.
Adil Y. Al-Handal 《International Review of Hydrobiology》1995,80(1):89-102
79 taxa of desmids belongig to 17 genera were observed in 17 samples collected from several parts in Basrah district, South Iraq. 3 genera viz. Actinotaenium, Docidium and Spondylosum, and 41 taxa are new records for Iraqi waters. Distribution of taxa in the area studied as well as in the whole country (when available) are given. Some slight morphological variations in desmids were observed due to the alkaline nature of water. 相似文献
4.
The orchids in Hainan.were reported containing 58 genera,143 species and two varieties in Flora Hainanica(1977).Since then a number of papers have been published and many specimens collected.The present paper deals with new,little known or noteworthy orchids in Hainan,concerning 36 genera,57 species and one variety,of which two (Bulbophyllum obtusiangulum Tsi,Sunipia hainanensis Tsi) are new to science and 18 new to Hainan,In addition,one new name(Ceratostylis hainanensis Tsi) is proposed and five names are reduced to synonyms.So far,there are altogether 68 genera,178 species and three varieties of orchids known from Hainan Island. 相似文献
5.
As part of the general study of the hydrobiology of the southeastern Nigerian deltaic waters, phytoplankton samples were collected (Jan.–August, 1981, to Dec., 1984 irregularly). Sixty-seven species were identified, thirty-nine of which were diatoms. The diatoms constituted the dominant taxa especially in the brackish zone while desmids, green algae and blue-green algal species occurred more commonly in the freshwater usptream zone. 相似文献
6.
Suspended and benthic algal communities from a mildly acidic, third-order Rhode Island stream were examined to determine the seasonal distribution, abundance and diversity of the lotic desmids. Within a one-year sampling period, 148 species and 202 subspecific taxa of desmids were identified, representing 23 genera. Species of Cosmarium and Closterium accounted for approximately 70% of the desmids present, and were the most diverse and abundant taxa during all seasons except spring, when Hyalotheca dissiliens was the dominant desmid species. Average abundance and species richness generally were greatest during summer for both suspended and benthic desmids. Most desmids occurred in benthic habitats, and were randomly distributed among substrata. Average seasonal abundance was 7.4 × 104 cells·g?1 dry wt substratum, among 13 types of substrata. Highest desmid abundance was measured among substrata with intricate morphologies, such as Fontinalis spp., which was associated with 1.2 × 106 desmid cells·g?1 dry wt substratum, or 1.7 × 103 cells·cm?2 substratum. Cell division was observed for 70 desmid taxa, and average seasonal reproduction (based on cell numbers) among all substrata ranged from 4% in winter to 20% during summer. In addition, sexually produced zygospores were found occasionally for H. dissiliens. Desmids were distributed among most substrata examined in this stream, with abundance comparable to reported estimates from softwater lakes and acid bogs. In contrast to established dogma, lotic desmids are not incidental drift organisms, but rather comprise a viable and persistent component of the stream periphyton. 相似文献
7.
Desmids from the Auvergne (France) 总被引:3,自引:2,他引:1
Frans A. C. Kouwets 《Hydrobiologia》1987,146(3):193-263
An investigation has been made into the present occurrence and distribution of desmids in the French Auvergne. 27 samples from different habitats revealed the presence of 280 taxa belonging to 251 species, of which 120 had not previously been recorded from this region.The number of taxa per sample varied from 2 to 118; especially the samples from mesotrophic lakes were very rich in desmid species. An annotated list with corresponding figures of the recognized taxa is presented, and previous reports relating to desmids from the study-area are discussed. 相似文献
8.
Adaptive strategies of desmids in two tropical monomictic lakes were studied in relation to morphometric differences. The study aimed at evaluating desmids' strategies during inter-annual succession patterns in two tropical lakes (Dom Helvécio and Carioca) in southeast Brazil. From monthly samples of freshwater algae collected during five consecutive years (2002–2006) from the two lakes, the desmids were classified according to size, life form, and life strategies (competitive, stress tolerant, and ruderal). Our results indicated that Lake Carioca (19º45′20″S, 42º37′12″W), a small, shallow, turbid, and mesotrophic system showed dominance of invasive/opportunistic taxa (C) and R-strategists (Staurastrum species <20 μm), whereas Lake Dom Helvécio (19º45′–19º48′45″S, 42º33′45″W), a large, deep, and clear system was dominated by ruderal (R) species (Closterium aciculare and Pleurotaenium trabecula >50 μm) and tolerant to stress (S) species (Staurastrum and Staurodesmus species >20 μm). A significant number of desmids from the lakes had low MLD (≤20 μm), low volume (<103), and high SV?1 ratio (>1). Consequently, C-strategist species were abundant and formed a group having great adaptive value in the lakes, with higher resilience and capacity to change composition after the turnover period. Stratification stability and atelomixis were the main driving forces to sustain high desmid biomass in these two lakes, despite the greater macrophyte richness and great water column depth at Lake Dom Helvécio and the main factor influencing richness and contribution of complex forms. 相似文献
9.
More than thirty species and varieties of Fritillaria have been reported from Xinjiang,incluing many new taxa recently published. A revision of these was made based on mainly herbarium material and literature.As a result,seven species were recognized,including newly recorded F. stenanthera(Regel)Regel,and nine species and twenty-one varieties were reduced to synonyms. 相似文献
10.
214 taxa under 21 genera of desmids have been described and illustrated from Bangladesh, of which 3 species and 8 varieties are new to science. 相似文献
11.
Moreno-Ruiz JL Tapia-García M González-Macias Mdel C Figueroa-Torres MG 《Revista de biología tropical》2008,56(1):27-54
Phytoplankton species collected from the limnetic to euryhaline sections of Tehuantepec River were identified, classified and compared with regional information from Mexico and South America. We collected 15 samples every three months from July 1997 through August 1998 with a 20 microm net and a Van Dorn bottle. Indicator values and a code checklist are included. A total of 58 families, 121 genera, 273 species, one subspecies, 75 varieties, 13 forms and one morphotype were identified in the taxa Bacillariophyta (42.0 %), Chlorophyta (29.0 %), Cyanoprocaryota (18.0 %), Euglenophyta (5.0 %), Dinophyta (3.0 %), Cryptophyta (2.0 %) and Chrysophyta (1.0 %). The predominant families were Scenedesmaceae (24 species), Oocystaceae (22), Bacillariophyceae (21), Chaetocerotaceae (15) and Euglenaceae (14). Five families, eight genera, 72 species, 45 varieties and eight forms are first records for Mexico. The species Chroococcus turgidus, Microcystis flosaquae and Pseudanabaena limnetica (which produce massive blooms or red tides) are important in this river of moderate water quality. 相似文献
12.
Information on changes over time in the biodiversity and ecology of tropical systems is of increasing importance against the background of local, regional, and global dynamics. This study aimed to contribute with long-term data on the abundance fluctuations of two species of echinoderms from a tropical tidal flat. From February 1984 to December 1986, March 1985 to April 1987, and July 1994 to September 1996 (total: 76 dates), core samples (17.7 cm2, 15 cm deep) were collected at low tide at a mud-sand flat in the mid upper Gulf of Nicoya estuary, Costa Rica, as part of a survey of the benthic community. Among more than 100 taxa, the burrowing brittle star, Amphipholis geminata, and the sand dollar, Mellitella stokesii, consistently appeared in the samples over the study period. A total of 63 M. stokesii and 149 A. geminata were collected. The 43 sand dollars found during 1984-1985, give an approximate density of 35 ind./m2, which is within the range reported for this species. M. stokesii was almost absent from 1994 to 1996, while A. geminata had its peak of abundance at the end of 1995. Low abundances of the sand dollar during the rainy seasons (May-November) and slight increments in dry seasons (December-April) cores, also agrees with a report from the region. A. geminata also presented an irregular pattern of abundance, with slight increases at the end of the rainy seasons or during the dry seasons, when higher salinities are more suitable for echinoderms. The patchy spatial distribution of both species makes difficult the detection of patterns with a corer. Nevertheless, this information is unique due to its extensive time coverage and provides a baseline for future surveys designed specifically for the study of tropical intertidal estuarine echinoderms. 相似文献
13.
Silva Ide G Moura Ado N Dantas EW Bittencourt-Oliveira Mdo C 《Revista de biología tropical》2010,58(4):1421-1436
Natural lake systems represent important reservoirs for residential water supply, fish production, recreational activities and enjoyment of their natural beauty. Nevertheless, human impacts may affect their health status resulting in degradation and loss of biodiversity. The aim of the present study was to obtain data on the health status of a natural lake located in an indigenous reservation in the Brazilian Amazon, using the phytoplankton community changes along the rainy (June) and dry (November) seasons of 2006. We collected water (temperature, pH, Secchi depth and conductivity) and phytoplankton samples from the subsurface, middle of the water column, and approximately 30 cm above the bottom, over 24-hour sampling periods, from a central station in the lake. Samples taken from biotic and abiotic variables were correlated using canonical correspondence analysis (CCA). Results showed that the lake exhibited high temperatures in both seasons, and showed thermal stratification only during the rainy season. Dissolved oxygen exhibited a clinograde pattern in the rainy season and high oxygen in the hypolimnion in the dry season. In the rainy season, the water near the bottom was acidic, turbid and had a greater concentration of phosphorus. Dissolved oxygen, conductivity, pH, nitrite, total phosphorus and total dissolved phosphorus exhibited diel variations in the rainy season, whereas water temperature, dissolved oxygen, total nitrogen and total dissolved phosphorus exhibited significant differences between hours of the day in the dry season. The phytoplankton was represented by 39 taxa, and Chlorophyta showed the greatest species richness, totaling 25 taxa. Among Chlorophyta, desmids were the most diverse, accounting 52%. Bacillariophyta (nine species) was the second most diverse group. Cyanophyta was represented by three species, including Merismopedia tenuissima, the most abundant taxon. Despite the occurrence of taxa that indicate organic pollution, their biomass and frequency indicate that the system is not currently threatened. Lake Caracaran? is an oligotrophic system, with low algal density and isolated blooming episodes due to its shallow depth. 相似文献
14.
D.B. Williamson 《Plant Ecology & Diversity》2013,6(1):113-122
Summary Samples from bogs and lochs collected in the parish of Assynt, south — west Sutherland; loch and pool samples from Shetland; tarn samples from Cumbria and a small pool in Oadby, Leicestershire, have been examined. New desmid varieties and formae, some rare desmids and interesting observations on common desmids can be reported. 相似文献
15.
Studies on coccolithophorids in Mexico are rather scarce, probably due to the use of traditional methods for studying marine phytoplankton (e.g. collection, preservation and analysis). This is the first study of the coccolithophorid flora from west coast of Baja California, Mexico. Bottle samples (4 l) were taken at various depths (5, 25 and 50 m), at fixed stations located on perpendicular transects along the west coast of Baja California, considering three different zones: North, Central and South. A total of 32 samples were studied by optical and scanning electron microscopy, yielding 24 taxa identified (17 species and 5 nominal varieties, plus 2 different varieties). The coccolithophorid assemblages are considered subtropical and coastal (with many cosmopolitan taxa). Emiliania huxleyi and Gephyrocapsa oceanica were the most abundant (relative abundance) and widespread species in the study area. We report 15 new records for the Mexican Pacific. The zonal and vertical distribution of some taxa are briefly discussed, as well as the taxonomy of Rhabdosphaera claviger, Helicosphaera carteri, H. hyalina and related taxa. 相似文献
16.
Wang Shu-Song 《植物分类学报:英文版》1989,27(4):310-316
Anhui Province is situated in the subtropical and temperate zones. With favorable
climate this district is rich in algae. During 1982-1986, the author made a number of collections of the algal specimens-about 1000 samples from 36 counties and cities of the province. The identification result shows that there are about 30 species and 15 varieties of Scenedesmus in the province.
In present paper, however, reported are only some new taxa and new records of Scenedesmus. The 4 new species are Scenedesmus anhuiensis, S. huangshanensis, S. quadrialatus
and S. wuhuensis, the 2 new varieties are Scenedesmus prismaticus var. spinosus and S. smithii
var. spinulosus, and the 4 new records of distribution in China are Scenedesmus denticulatus
var. australis Playfair, S. prismaticus Bruhl et Biswas, S. quadricauda var. dentatus Dedussand S. smithii Teiling. 相似文献
17.
本文研究了中国产粗叶本属植物30种4亚种和7变种的地理分布,划分出三个分布区类型,十二个变型和四个亚变型。根据种多度和分布特征,中国粗叶本属植物在分布上表现出与中国的热带雨林、季雨林区,南亚热带常绿阔叶林带和中亚热带常绿阔叶林带相匹配的分布规律,并受几条植物地理界线的作用。通过对地理替代类群和一些特殊分布式样的分析,显示了所谓的“田中线”和一条北起四川峨眉向南经贵州西南部至广西西部的界线对粗叶木种的分布,特别是对中国-喜马拉雅和中国-日本替代分布具有明显的作用。这导致笔者认为“田中线”作为中国-日本分布的西界而另一第线作为中国-喜马拉雅分布的东界。进一步的分析还揭示由云南南部沿缅甸、泰国向南延伸的横断山余脉既充做一条植物南-北迁移的通道又是一条中南半岛西部(印-缅)与东部(印度支那-华南)的植物地理界线。 相似文献
18.
19.
陕西省啮齿动物区系与区划 总被引:25,自引:3,他引:22
陕西省地处我国的中部偏东,气侯和植被兼具亚热带和暖温带特点,在动物地理上横跨古北与东洋两大界,啮齿动物种类比较丰富。计有53种另附9亚种,分隶于2目8科6亚科,几乎占全国啮齿动物总种数的三分之一。大足鼠为陕西省首次记录。文中就区系特征作了分析。根据自然地理要素和动物区系的差别,陕西省可划为六个三级地理省。 相似文献
20.
《Fungal Ecology》2021
Interactions between diverse groups of organisms influence the functioning and diversity of ecosystems. Salient examples of such relationships are those among hypogeous fungi, trees and mycophagous mammals. To investigate the role of small mammals in transporting fungal spores within and outside forests as well as the influence of seasons, habitats and species on small mammal mycophagy, we set up a study in the Pieniny Mts, Western Carpathians (Southern Poland). The droppings of small mammals were collected during live trapping in July and September 2016 and 2017, to analyze richness, composition and frequency of fungal spores present in faeces. The yellow-necked mouse Apodemus flavicollis, the bank vole Myodes glareolus and the common vole Microtus arvalis were the most frequently trapped. Spores of 27 fungal taxa from 16 genera were retrieved from nearly 70% of faecal samples of rodents and shrews, with up to 9 spore taxa recorded per sample. Spore diversity in samples was higher in September than in July, although seasonal variation was year and animal dependent. The highest mean number of fungal taxa per sample was recorded for the bank vole and the yellow-necked mouse, with the former species showing a higher degree of mycophagy. The two rodents differed in the average frequencies of consumed fungi in samples, which could result from some degree of specialization in the choice of particular fungal species, as shown by the laboratory-based experiment. Within particular animal species, differences in the fungal diet were found between seasons. The spores of hypogeous fungi were transported from forests to meadows mostly by the yellow-necked mouse and, to a lesser extent, by the common vole. However, both, the diversity and the number of transported spores diminished with distance from the forest edge. 相似文献