Assessment of Rarity Category for Higher Aquatic Plants

A spatiotemporal analysis of higher aquatic plant flora in the water bodies of the city of Kyiv (Ukraine) has been used to develop local protection criteria for 22 rare and protected species. These criteria differ considerably from the regional ones due to the significant transformation of the environment in an urban landscape. The rare component of macrophyte flora in the water bodies of the city have become poorer over the past 40–50 years; two species have disappeared from the urban flora, seven species are characterized as critically endangered, five species are endangered, four are vulnerable and at a high extinction risk, and four more species are characterized by a low risk of extinction.     

Seaweed biogeography of the mid-Atlantic coast of the United States

The northern boundary of the warm temperate region of the mid-Atlantic coast of the United States is set at Cape Hatteras; the southern boundary lies at Cape Canaveral. There is some spillover of cool temperate species south of Cape Hatteras into North Carolina and spillover of warm temperate species south of Cape Canaveral toward Palm Beach. Elements of the warm temperate flora also extend into the northern Gulf of Mexico, but precise limits to the flora cannot be drawn there. Thirty-one species are endemic to the warm temperate flora. The inshore waters of North Carolina include approximately equal numbers of species with northern and southern centres of distribution; the species of the offshore waters have predominantly southern affinities, but also include most of the endemic species. Seasonal changes in the shallow water flora of North Carolina reflect eurythermal cool temperate and tropical elements in winter and summer respectively and a year-round warm temperate element. These groupings have been verified by experimental studies in which light and temperature were varied. The deep water flora is a summer flora dominated by perennial species. The inshore, eurythermal cool temperate and tropical species have a variety of cryptic stages by which they persist throughout the year.Paper presented at the Seaweed Biogeography Workshop of the International Working Group on Seaweed Biogeography, held from 3–7 April 1984 at the Department of Marine Biology, Rijks-universiteit Groningen (The Netherlands). Convenor: C. van den Hoek.     

阴山山脉乌拉山段种子植物区系组成及特征研究

通过对阴山山脉乌拉山段种子植物区系进行调查、统计、排序,从科、属、种3个分类等级上对植物的地理分布类型、生活型、水分生态类型分别进行统计分析,并与内蒙古种子植物区系进行对比分析。结果表明:(1)乌拉山有野生种子植物67科,227属,426种,其中,裸子植物3科,5属,7种;双子叶植物58科,187属,345种;单子叶植物6科,35属,74种;(2)从地理成分来看,温带成分占绝对优势;生活型以草本植物占绝对优势;从水分生态类型看,中生植物是该区的主要成分,旱生植物在本区系也占有相当比重,说明该地区水分条件较差,在气候区上属于半干旱地区;(3)与毗邻山地植物区系的相似性分析表明,乌拉山植物区系与九峰山、大青山种子植物区系具有很近的亲缘关系,与狼山亲缘关系较远。     

Changes in the Aral Sea ecosystems during the period 1960–1990

Salt and water balance in the Aral Sea are described together with the endemic fauna and flora which were mainly of freshwater origin. During the last thirty years the fauna and flora have undergone dramatic changes due partly to a great increase in salinity as the result of water abstraction from the inflowing rivers and partly as the result of the deliberate and accidental introduction of a wide variety of marine invertebrates and fishes. The increased salinity has eliminated most the species of freshwater origin while many of endemic saline species have been lost as the result of competition with the marine ones. Changes in productivity are described and future prospects for the sea are discussed.     

Persistence, extinction and different species pools within the flora of lake islands in western Ireland

The vascular flora on twenty-nine lake islands in Lough Corrib, western Ireland was surveyed in 1992–93. Thirteen of these islands had been surveyed by the author in 1974 (Roden, 1979). Data on species–area curves and species turnover between 1974 and 1992 are presented. Species numbers on each island did not change greatly in the 18-year interval and extinctions were most common on smaller islands. It is known that six of the islands surveyed are less than 150 years old and their flora must have immigrated over open water during that period. It is shown that this group of species has a different log species/log area regression than the remaining flora, with a much shallower slope (low Z value). The proportion of less widespread species was greatest on islands nearest to the mainland. The implication of different slopes in different species groups and the restriction of turnover to rare species is discussed with reference to the island Theory of Biogeography.     

Marine macroalgal biodiversity hotspots: why is there high species richness and endemism in southern Australian marine benthic flora?

The southern Australian marine macroalgal flora has the highest levels of species richness and endemism of any regional macroalgal flora in the world. Analyses of species composition and distributions for the southern Australian flora have identified four different floristic elements, namely the southern Australian endemic element, the widely distributed temperate element, the tropical element and a cold water element. Within the southern Australian endemic element, four species distribution patterns are apparent, thought to largely result from the Jurassic to Oligocene fragmentation of East Gondwana, the subsequent migration of Tethyan ancestors from the west Australian coast and the later invasion of high latitude Pacific species. Climatic deterioration from the late Eocene to the present is thought responsible for the replacement of the previous tropical south coast flora by an endemic temperate flora which has subsequently diversified in response to fluctuating environmental conditions, abundant rocky substrata and substantial habitat heterogeneity. High levels of endemism are attributed to Australia's long isolation and maintained, as is the high species richness, by the lack of recent mass extinction events. The warm water Leeuwin Current has had profound influence in the region since the Eocene, flowing to disperse macroalgal species onto the south coast as well as ameliorating the local environment. It is now evident that the high species richness and endemism we now observe in the southern Australian marine macroalgal flora can be attributed to a complex interaction of biogeographical, ecological and phylogenetic processes over the last 160 million years.     

Tropical high Andean drylands: species diversity and its environmental determinants in the Central Andes

Diversity determinants have mostly been evaluated in high diversity areas, leaving behind regions with less species diversity such as drylands. Here we aim to analyze the patterns of plant diversity in tropical drylands in the southern Central Andes, and determine the importance of water, energy, and environmental heterogeneity as diversity determinants of the arid and semi-arid adapted flora. We examined the distribution of 645 native species from lowlands to 6000 m.a.s.l. in the north-western region of Argentina (NWA) and define hotspots of diversity within each NWA ecoregion. Diversity is concentrated in regions of middle elevation with intermediate values of water and energy, at the transition between arid and semi-arid regions. Furthermore, we showed that in tropical drylands energy input is as fundamental for plant diversity as water input is and, we found that the effects of these variables varied with elevation and, also with aridity. Water variables had the strongest effect on the flora in the arid high Andean ecoregions, where an increase in precipitation during the growing season stimulated species diversity. Energy only became more important than water when the arid adapted flora entered the low and semi-arid regions where energy increments reduce species diversity. Our analysis provides strong quantitative support for climate variables as the main determinants of plant diversity across different ecoregions of the southern Central Andes. Given the present climate change events, knowing how these variables affect the distribution of the arid adapted flora is crucial for planning strategies for achieve their present and future conservation.     

THE LICHEN VEGETATION OF ACID WATERCOURSES IN ENGLAND

The lichen vegetation of forty-five acid watercourses in England is described and related to ecological variables. The zonation scheme adopted for chalk and limestone streams that involves four overlapping bands of lichen vegetation related to length of submergence is also appropriate for this habitat. The flora involves around 90 species, a number of which are rarely recorded specialists. Evidence is presented that substratum chemistry is a more powerful ecological factor than water chemistry. An attempt has been made to relate the lichen flora to homogeneous stream segments from the headwaters down to the alluvial lowlands. An investigation into the effects of water quality showed that both suspended solids (silting) and eutrophication are highly deleterious to the lichen flora; the submerged and fluvial mesic zones are the first to be affected. The zonation across streams in England is compared with those reported from Germany and found to be closely similar.     

锡林郭勒草原国家级自然保护区种子植物区系研究北大核心CSCD

该研究以查阅文献和野外实地调查相结合的方法,对锡林郭勒草原国家级自然保护区种子植物进行调查、统计、排序,并对该区系种子植物的种类组成、水分生态类型、生活型及种的地理成分进行分析。结果表明:锡林郭勒草原国家级自然保护区有野生种子植物856种,分别隶属于87科,345属;其中,裸子植物3科,5属,11种;被子植物84科,340属,845种。植物水分生态类型以中生植物为主,共559种,占区系总种数的65.30%;旱生植物213种,占区系总种数的24.88%。生活型以草本植物为主,占区系总种数的88.67%。区系中种的地理成分较为复杂,既反映出保护区植物地域性强的特征,也反映出该区域生境类型多样、植物丰富度高的特征。     

苗儿山植物区系的初步研究

<正> 苗儿山自然保护区是我国亚热带天然林保存较好、并有一定代表性的林区之一。它的植物区系成分复杂,植物种类繁多,古老孑遗植物丰富。研究其植物区系的组成和特点,对进一步研究广西乃至我国的植物区系,及开发利用保护区内的植物资源,使之更好为我国社会主义建设服务,均有一定的意义。     

Diversity and ecological characteristics of vascular flora in Mediterranean temporary pools

Vascular flora of Mediterranean temporary pools has been studied with the aims to define its diversity and to individuate the ecological characteristics of the different plant groups associated with this relevant and endangered habitat type. Overall, 246 species were found of which 108 were terrestrial, 57 generalist of aquatic or wet habitats and 81 typical of temporary water and strongly linked to temporary pools. The results suggest that: (i) vascular flora associated with Sardinian Mediterranean temporary pools is rich and diversified; (ii) rare ferns are better represented than previously reported; (iii) plant species are generally heliophilous and acidophilous, specialized temporary pool species mainly differing from the unspecialized ones in relationship to their soil moisture requirements; (iv) these habitats are particularly important for maintaining regional freshwater biodiversity.     

湖北蕨类植物区系基本成分和主要特点的探讨

在湖北蕨类植物区系中,属种数量最多的科有水龙骨科(Polypodiaceae)、鳞毛蕨科(Dryopteridaceae)和蹄盖蕨科(Athyriaceae)。并以鳞毛蕨属(Dryopteris)、耳蕨属(Polystichum)和蹄盖蕨属(Athyrium)为最主要代表。区系的主要特点为:种类丰富,地理成分错综复杂,联系广泛,显示出多种区系成分交叉在一起的过渡特色。     

Summer in the Ensenada Front: The distribution of phytoplankton species, July 1985 and September 1988

Two interdisciplinary cruises took place in the Ensenada Frontalregion during July 1985 and September 1988. This paper discussesthe distribution of phytoplankton species along one sectionfrom each cruise. Each year, the overall dominant species wasEmiliania huxleyi. Although hydrography of the euphotic zoneindicated the presence of water from three sources, the CentralPacific flora dominated the floral patterns. Recurrent groupanalysis identified two clusters of related groups of species,present in both years and separated by depth. These were similarto recurrent groups defined from the Climax area in the CentralNorth Pacific. Similarity maps indicated the presence of thetwo-layered structure that is characteristic of the CentralPacific flora. The transition between flora corresponded tothe depth of the chlorophyll maximum layer but also to the coolsalinity minimum layer that marks California Current water andthat is absent from the Central Pacific. The extensive entrainmentand persistence of Central Pacific flora in the Ensenada Frontalregion is unexpected.     

The intertidal algal flora of Isipingo Beach,Natal, South Africa,and its phycogeographical affinities

The intertidal seaweed flora of Isipingo Beach, Natal, is described. Isipingo Beach lies on the sub-tropical east coast of southern Africa and is the only east coast locality studied in detail by pioneering biogeographers. A total of 172 species (37 chlorophytes, 26 phaeophytes and 109 rhodophytes) are recorded. A phycogeographical analysis of 124 species with sufficiently documented distributions, shows that 69% are warm water species also known from the tropical coasts of Mozambique, Tanzania and Kenya. The phycogeographical affinity of the Isipingo flora is certainly with sub-tropical and tropical floras.     

Phytoperiphyton of the Samarga River basin (Primorskii Krai)

In the periphyton of the Samarga River basin, 313 species of algae (337, including infraspecific taxa) from eight divisions have been found. The groups of algae from the river main flow, creeks, streams, and the mouth are described. Data on the density and biomass of periphyton algae are presented. A decrease in these parameters after a flood is shown. In algal flora composition, benthic oligohalobic species of algae, preferring a slightly alkaline environment, dominate. At the river mouth a significant amount of mesohalobic species has been observed. A sanitary and biological evaluation of water quality has shown that the mass development of xenoand oligosaprobic algae defines the excellent quality of the river water. All parts of the main flow correspond to the oligosaprobic purification zone, class II of water purity (saprobic index of 0.95–1.48). The good quality of the Samarga River water is ensured by the absence of pollution sources and the satisfactory condition of its catchment area forests.     

Species richness and endemicity in the Spanish vascular flora

Data from an updated and revised checklist of the Spanish flora is analyzed. The Spanish vascular plant flora is composed of 204 families, 1433 genera and 7071 species. Floristic data are analysed by considering three regions: mainland Spain with 5984 species, the Balearic Islands with 1521 species and Canary Islands with 2066 species. Extinct species are included in the analysis, with an extinction rate of 0.35% of the flora. A total of 1488 endemic species are recognized, which account for 21% of the Spanish flora. The rate of endemism in the Canary Islands is 25.9%, considerably higher than for the Balearic Islands (6.9%) and for mainland Spain (13.8%). A list of the 35 strict endemic genera is compiled, of which 65.7% are Canarian, and another list of 27 subendemic genera of which 48.1% are also Canarian. An estimated 12% of the Spanish flora is non‐native, with large variation between the 20.7% of the Canary flora, 10.5% of mainland Spain and 9.7% of the Balearic Islands. Finally, the composition of the Spanish flora for large groups and families is ana lysed. The data show that species richness and endemicity rates have been overestimated by previous authors, and are similar to other Mediterranean countries. It is concluded that a complete revision of the Macaronesian flora is strongly needed to obtain an accurate comparison with the flora of other areas.     

Changes in aquatic macrophyte flora over the last century in Catalan water bodies (NE Spain)

Landscape and aquatic environments have suffered increasing threats over the last century with major impacts on lentic waters and, presumably, on its inhabiting life. This study aims to evaluate changes in occurrence of aquatic macrophyte flora in lentic waters in Catalonia (NE Spain), emphasizing the last 20 years, with particular reference to vulnerable species. We conducted a survey (2005–2009) identifying macrophytes from 215 lentic water bodies (from eight different geomorphological typologies) and compared the data obtained with a historical compilation (1879–2006) from the Biodiversity Data Bank of Catalonia (BDBC). Vascular hydrophyte species were present in 53.5% of the sampled water bodies and only 69.7% of species cited in the BDBC were re-sampled in the recent survey. Significant changes in species occurrence were also found, particularly for those endangered macrophytes where the ratio of re-sampling was lower (52%). Hydrophyte flora of 36 water bodies has changed over the last 20 years and richness clearly tends to decrease. However, trends are different in each typology; while richness is stable in alpine lakes, it drops for coastal lagoons, ponds and karstic lakes. The threats most correlated with hydrophyte disappearance are water extraction and regulation and desiccation/drainage. To sum up, we detect a loss of hydrophyte diversity at a local and regional scale. Conservation actions are needed to preserve remaining water bodies and flora.     

小肠内容物菌群及膜菌群的研究

作者借助小肠镜及结肠镜于正常国人空肠及回肠中取材,共检测了３０例的肠内容物菌群及膜菌群,对１０种有代表性的需氧及厌氧菌进行了定性及定量分析,并对各菌株均作了生化鉴定,其结果显示空肠梭菌、回肠梭菌、乳杆菌及双歧杆菌的肠内容物菌群与膜菌群有显著差异。３０例空肠内容及粘膜组织中均未培养出肠球菌。大肠杆菌在空肠的腔菌群及膜菌群有１６／３０,１０／３０例,类杆菌有１２／３０和１０／３０例生长,并讨论了上述结果的意义。     

DISTRIBUTION OF PHYTOPLANKTON IN A POLLUTED SALINE LAKE,ONONDAGA LAKE,NEW YORK1,2,3

Onondaga Lake, possibly the most polluted lake in New York State, supports an algal flora characteristic of a eutrophic lake with an admixture of saline species. Floral diversity is noteworthy under the circumstances. Seasons in the lake may be identified by the succession of flora. High salinity of lake water results in layering at the outfall (as in an estuary, in reverse) such that river water may enter the lake at the outlet despite continuous net outflow. Certain species of algae appeared first at the outflow station and then spread through the lake. Phosphorus and nitrogen are never limiting, although seasonal diminution in the latter may influence the composition of the flora. Silica diminution was related to blooms of diatoms and may then be limiting for further growth of diatom populations. No obvious controlling relationship exists between herbivores and phytoplankton populations. The euphotic layer is typically much shallower than the thermocline. Therefore turbulence and mixing may play an important role in controlling certain populations. A brief midsummer clearing in 1969, characteristic for the lake, resulted in serious oxygen depletion and cannot be accounted for with the available data. Among metals, chromium and copper are high in the lake as the result of industrial discharges. The former may be inhibiting, the latter probably is inhibiting to algal growth. Consequently, measures underway to “clean up” the lake may result in increased blooms. Biomass calculations have been made for the major phytoplankters, and a list of 82 species is presented.