A study of Bacillariophyta flora in water bodies and water courses of the Messoyakha River (Gydansky Peninsula)

A total of 236 species and intraspecific taxa of Bacillariophyta diatoms from 55 genera, including 15 new ones for Russian flora, were found in an SEM study of phytoplankton in Lake Glubokoe and large tributaries (Nizhnyaya Messoyakha, Purparod, Erparod, Paravanga, and Nyakhataparod) in the basin of the lower reaches of the Messoyakha River. The maximum species diversity was recorded in the tributaries Nizhnyaya Messoyakha (117), Nyakhataparod (109), and Lake Glubokoe (97). The following species are the most widespread in the studied water bodies: Asterionella formosa, Aulacoseira subarctica, Navicula cryptocephala, Nitzschia gracilis, and Tabellaria flocculosa.     

Materials on the flora of Bacillariophyta in rivers of the white sea basin in the Republic of Karelia

A total of 290 species and varieties of Bacillariophyta including 32 that were new for the flora of Karelia and 18 that were new for the flora of Russia, have been recorded in phytoplankton in nine rivers of the White Sea basin. The genera Aulacoseira, Pinnularia, Eunotia, and Navicula s. l. are the richest in taxonomy. The maximum species diversity was recorded in the Suma (73), Kolezhma (91), and Chirko-Kem (146) rivers. The following species are the most widespread in the rivers that were under study here: A. ambigua, A. subarctica, A. subborealis, {tiA. tenella}, Asterionella formosa, and Tabellaria flocculosa.     

Campanian flora of the Bureya River basin (Late Cretaceous of the Amur Region)

A general characterization of the Campanian flora of the Amur Region is provided based on a floristic assemblage from the upper member of the Kundur Formation (Amur Region) and its stratigraphic analogue, the Taipinglinchang Formation (northern China). New species of Trochodendroides and Celastrinites are described; and a new combination, Arthollia tschernyschewii, is proposed.     

Distribution patterns of freshwater molluscs along environmental gradients in the southern Guadiana River basin (SW Iberian Peninsula)

The taxonomic status of the freshwater mollusc fauna of the Iberian Peninsula it is reasonably well known, but, unlike other benthic macroinvertebrate, its distribution and ecology has been poorly studied. In this article, I study the relationships between environmental characteristics and distribution and community structure of freshwater molluscs along climatic, hydrological, physicochemical, and heterogeneity gradients in the southwestern Iberian Peninsula. Ninety-four sampling points were analysed, in which, in addition to habitat features, the presence/absence and abundance of species were evaluated. The environmental gradients were measured by use of principal-components analysis (PAC), which orders the variables along two gradients: headwaters-mouth gradient (PC1) and water availability (PC2). According to canonical correspondence analysis (CCA), the main environmental factors related to species distribution and community structure were conductivity, permanency, channel width, turbidity, slope, and distance to the main river axis. The relationship between biodiversity (measured as species richness and the Shannon–Weiner diversity index), the ratio of the number of introduced species to the total number of species (zoogeographic integrity coefficient), and environmental variables was best explained by a regression model incorporating, basically, the permanence of water in streams as the variable that accounted for most of the variance. This study demonstrates that the distribution of freshwater molluscs along a Mediterranean gradient highly stressed by drought depends, mainly, on the hydrological stability and environmental conditions of the headwaters and estuarine sites.     

Materials for the fungus flora of Japan (51)

A discomycete in Sarcoscyphaceae is described and illustrated as new to Japan:Cookeina sulcipes (Berk.) Kuntze, found on decayed wood along the Aira River, Iriomote Island, Okinawa Pref., Japan. Hongo, T., Nippon Kingakukai Kaiho (Trans. Mycol. Soc. Japan)38: 99–100, 1997.     

Materials for the fungus flora of Japan (48)

A coelomycetePolymorphum quercinum, newly found on the branches ofFagus crenata in Japan, is described.(47): Kobayashi, T. et al., Mycoscience 35: 399–401, 1994.     

Materials for the fungus flora of Japan (55)

From recent isolates of microfungi on soil materials collected at several localities in Japan, three onygenalean species are described and photographed as new to Japan:Aphanoascus durus, Kuehniella racovitzae, andShanorella spirotricha. (54) Yokoyama, T. and Nasu, H., Mycoscience41: 91–93, 2000.     

Effects of suspensoids (turbidity) on penetration of solar radiation in aquatic ecosystems

In mainland Australia and in southern Africa, the aridity of the climate and sparse vegetative cover increase the susceptibility of the soils to erosion, and as a consequence surface waters are usually turbid. The inanimate suspensoids in such waters, the tripton fraction of the limnologist, are responsible for virtually all the light scattering, and also, by virtue of the yellow-brown humic materials adsorbed on their surface, for a substantial part of the light absorption. Spectral absorption data for suspensoids in terms of theirin situ absorption coefficient values, and the contribution of suspensoids to absorption of photosynthetically available radiation (PAR) are given for certain Australian water bodies.To understand the effect of suspensoids on attenuation of the solar flux with depth, the scattering coefficient must also be known, and this can be determined from the nephelometric turbidity or from up- and down-welling irradiance measurements. The effect of particle size on scattering efficiency is discussed.An equation expressing the vertical attenuation coefficient for downward irradiance as a function of absorption coefficient, scattering coefficient and solar altitude is presented, and is used to explore the effects of absorption due to dissolved colour and suspensoids, and the effects of scattering by suspensoids, on the penetration of PAR.Suspensoids, by increasing the rate of attenuation of the solar flux with depth, can greatly diminish the euphotic depth of a water body, with a consequent decrease in the ratio of the euphotic to the mixed depth: thus turbidity can reduce productivity of a water body substantially below that which might be expected on the basis of nutrient availability. Shallow turbid waters of low intrinsic colour can, however, be highly productive. By diminishing the depth of the layer within which solar energy is dissipated as heat, suspensoids can greatly modify the hydrodynamic behaviour of water bodies, and this also has far-reaching ecological consequences.Suspensoids drastically impair the visual clarity of water, a fact of major significance for the aquatic fauna, as well of aesthetic significance for humanity. The reciprocal of the Secchi depth is more correctly thought of as a guide to the vertical contrast attenuation coefficient rather than to the vertical attenuation coefficient for irradiance. The reflectivity of a water body, being at any wavelength proportional to the backscattering coefficient divided by the absorption coefficient, is highly dependent on the concentration, and optical character, of the suspensoids present. This has implications not only for the appearance (colour, muddiness) of the water to an observer, but also for the remote sensing of water composition by air- or satellite-borne radiometric sensors.     

Materials for the fungus flora of Japan (53)

Two interesting ascomycetes are described as new to Japan:Ascotricha amesii (Xylariaceae), isolated from garden soil in Osaka; andAuxarthron reticulatum, isolated from forest soil in Tokyo. ADicyma anamorph is associated with the former species. (52): Tubaki, K., Tokumasu, S. and Konno, M., Nippon Kingakukai Kaiho38: 249–250. 1997.     

Materials for the fungus flora of Japan (49)

Two interesting microfungi are described as new to Japan:Talaromyces galapagensis (anam.Penicillium galapagense), isolated from soil in Shizuoka; andPenicillium megasporum, isolated from marine sludge in Nagasaki. Some observations are recorded, particularly on ascomatal initials ofT. galapagensis, which are similar to those described forTalaromyces flavus.(48): Kaneko, S., Mycoscience 36: 359–360, 1995.     

Materials for the fungus flora of Japan (47)

Albophoma yamanashiensis isolated from a forest soil in Yamanashi Prefecture is described as a new genus belonging to Nectrioidaceae, Coelomycetes.(46): Hosoya, T. et al., Trans. Mycol. Soc. Japan 34: 429–432, 1993.     

Materials for the fungus flora of Japan (57)

Two microfungi are described as new to Japan:Amaurascopsis reticulatus (Amauroascaceae, Ascomycetes), isolated from forest soil in Kamakura, has not been recorded since it was originally found and is characterized by yellow to orange-red ascomata with undifferentiated peridial hyphae and globose ascospores with contorted ridges appearing irregularly punctate-reticulate; andHobsonia mirabilis (helicosporous hyphomycete), isolated from the cut stem of a thistle in Hachijo-jima, is characterized by gelatinous sporodochia and hyaline, tortuously coiled conidia. (56): Okuda, T. and Yamamoto, K., Mycoscience41: 411–414, 2000.     

Ecological implications of molluscan ontogenetic strategies - examples from aquatic ecosystems of the Cenozoic Iberian Peninsula

Molluscs from marginal marine and intra-continental basins of the Iberian Peninsula are described with special emphasis on the early ontogenetic shell formation, which reflects the embryogenesis and larval ecology. The fossils, covering a time span from the Early Oligocene to the Early Pleistocene, are compared to contemporaneous fossil faunas of the Mediterranean and Paratethys, and to extant Mediterranean faunas. Larval shells occur in bivalves and gastropods of Upper Tortonian coastal lagoons near Crevillente (Alicante), indicating marine larval stages and a connection of the adult habitat with the open sea. The euryhaline marginal marine gastropods display planktotrophic larval shells, which enable a marine distribution, but prevented generally euryhaline genera, such as Granulolabium and Terebralia (Cerithioidea, Potamididae), from colonizing continental saline ecosystems. The establishment of athalassic saline populations implies the preadaptational loss of planktotrophy. For the first time lecithotrophic larval development in an athalassic saline system is documented for Potamides gaudryi (Cerithioidea, Potamididae) from the late Middle to early Upper Miocene of the Duero Basin. With regard to the early ontogenetic development, P. gaudryi is distinguished from its possible descendant, the extant Potamides conicus (Blainville, 1829), which represents a direct developer that lacks any larval stage. In comparison to direct development, lecithotrophic larval development was advantageous in the colonization of temporary habitats, such as flood areas. Two different modes of direct development with hatching of crawling young are documented: Feeding on embryonic yolk until the hatching stage and adelphophagy. Adelphophagous embryonic development appears to be advantageous in neritids, thiarids and pulmonates that live in habitats with strong predation of juvenile fishes based on the advanced developmental stage and larger shell size of the hatchlings.     

A review of length–weight relationships of fish from the Segura River basin (SE Iberian Peninsula)

We present the relationships between fork length and total weight for 14 fish species from the Segura River basin (southeastern Spain): Barbus sclateri, Chondrostoma polylepis, Gobio lozanoi, Aphanius iberus, Micropterus salmoides, Lepomis gibbosus, Carassius auratus auratus, Cyprinus carpio carpio, Sander lucioperca, Gambusia holbrooki, Liza ramado, Mugil cephalus, Atherina boyeri and Pomatoschistus marmoratus. Significant length–weight relationships were found for all species. The values of the exponent b of the length–weight relationships ranged from 3.82 for Sander lucioperca to 2.59 for Micropterus salmoides.     

Alien flora of the Korean Peninsula

The Korean Peninsula has been divided into the countries of North and South Korea since 1948. This adoption of different political and socio-economic regimes has significantly changed economic activity and international exchange by those nations, thus affecting the introduction of alien plants. Our study objective was to provide a comprehensive, up-to-date inventory of the alien flora on the Korean Peninsula and to analyse how the partitioning between North and South Korea has influenced the numbers and status of those alien plants. We identified pre-1876 aliens that were brought to the Korean Peninsula before 1876, when Korea opened up to foreign countries, and also determined the post-1876 aliens that were introduced after 1876. Plants in the latter group were further classified into those that arrived before the outbreak of the Korean War in 1950 (1876–1950 aliens) and those introduced since then (post-1950 aliens). We investigated the regions of origin, family compositions, and invasion status of those alien taxa. In total, 504 alien taxa were identified, with 102 taxa being pre-1876 and 117 being 1876–1950 aliens. After the Korean War, the number of alien plants in South Korea more than doubled (276 taxa), whereas the number reported for North Korea was considerably lower (33 taxa). This might be due to enhanced economic activity and a larger human population in South Korea. Climatic differences as well as variations in the recording intensity for alien flora between North and South Korea may also have contributed to the large contrast in numbers of new alien species recorded during the last decades. Coordinated measures between the two nations are necessary if the spread of invasive alien plants onto the Korean Peninsula is to be reduced.     

海河流域河流生境功能识别及区域差异

城市群快速发展严重影响着区域水生态系统的完整性,大尺度流域的河流生境功能辨识和分析尚缺乏系统研究。以海河流域为例,根据河段蜿蜒度、河段比降、断流风险、盐度等4个指标,构建了河流生境功能的分类指标体系。通过多源空间数据和人工判读,划分了6254条河段,在此基础上将河流生境类型划分为15类。通过52个监测样点的鱼类调查数据,分析了不同河流生境的水生生物特征差异,揭示了鱼类多样性高的区域多位于河流比降大、断流风险低的区域,而河流蜿蜒度对于鱼类多样性影响较小。根据京津冀13个地级市的河流生境差异,提出京津冀城市群的生态安全构建需要充分考虑河流生境的空间异质性,并制定融合城市发展目标、水资源利用需求和河流生境功能的综合指标体系。     

秦岭南坡旬河中上游地区植物区系初步研究

植物各类组成是植被的重要特征之一,研究一个地区的植物区系有助于加深化对植被的认识。旬河流域中上游地区位于秦岭南坡。该地区植物种类丰富,共有种子植物１１２科３９５属７５０种。植物区系地理成分十分复杂,具有明显的温带特征。但和热带植物区系有一定联系。其起源也很古老,有８种植物属于原始的被子植物,并有８个单型属笔１１个少型属,还有许多孓植物。     

Didymosphenia geminata (Lyngbye) M. Schmidt (Bacillariophyta) in the Danube basin: New data from the Drava river (northern Italy)

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.     

A practical concept for the ecological assessment of aquatic ecosystems: application on the River Dore in France

The ecological assessment of freshwater ecosystems necessitates to consider (i) the operational biological classification for defining a range of ecosystem alterations, (ii) operational biomonitoring tools fulfilling the requirements of the classification, (iii) ecological quality objectives to be preserved or restored. The development of this biomonitoring approach was illustrated by the study of the River Dore. Four biological qualities were defined with their related bio-indicators: (1) general biological quality (invertebrates), (2) biological sediment quality (oligochaetes), (3) biological water quality (diatoms) and (4) biological fish quality (fish communities). The selected bio-indicators were adjusted to an ecological classification model, based on a range of 8 ecological qualities, from `pristine' (S0) to extreme toxicity (S7). The model allows to use numerical index values as well as methods without index calculations, and to assess the general ecological quality of the river and its time-dependent evolution. At the sites downstream of industrial discharges, an improvement of the general ecological quality was observed from 1983 to 1995 in relation to sewage-treatment actions. A general ecological quality objective is proposed for each site of the river, taking into account the past and present ecological evolution of the river. The relevance of the approach greatly depends upon the accuracy of bio-indicator adjustment to the classification model and would be enhanced by taking into account other biological characteristics, like trophic status and hyporheic biocenoses.     

Biology and Ecology of the Redpoll (Acanthis flammea sensu lato,Passeriformes, Fringillidae) on Yamal Peninsula and in the Near-Ob Forested Tundra

Biology Bulletin - The features of the biology, ecology, and annual cycle of the Redpoll in the near-Ob forest–tundra and subarctic tundra of Yamal are considered: distribution, habitats,...