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1.
A historical review. By the end of the 20th century, the composition of intertidal biota has been studied in all Russian Far Eastern seas; the specific features of vertical zonation in intertidal communities have been revealed; the major belt-forming communities of flora and fauna have been described and studied in the quantitative aspect; the existence of bionomic types in the intertidal zone, similar to those in the coastal area of the Barents Sea, has been corroborated; and some regularities have been retraced in the geographical zonation of different types of marine intertidal zone. The progress of the scientific school of Academician Oleg G. Kusakin has been particularly emphasized in the investigations of intertidal biota, communities and taxocenoses.  相似文献   

2.
China''s seas cover nearly 5 million square kilometers extending from the tropical to the temperate climate zones and bordering on 32,000 km of coastline, including islands. Comprehensive systematic study of the marine biodiversity within this region began in the early 1950s with the establishment of the Qingdao Marine Biological Laboratory of the Chinese Academy of Sciences. Since that time scientists have carried out intensive multidisciplinary research on marine life in the China seas and have recorded 22,629 species belonging to 46 phyla. The marine flora and fauna of the China seas are characterized by high biodiversity, including tropical and subtropical elements of the Indo-West Pacific warm-water fauna in the South and East China seas, and temperate elements of North Pacific temperate fauna mainly in the Yellow Sea. The southern South China Sea fauna is characterized by typical tropical elements paralleled with the Philippine-New Guinea-Indonesia Coral triangle typical tropical faunal center.This paper summarizes advances in studies of marine biodiversity in China''s seas and discusses current research mainly on characteristics and changes in marine biodiversity, including the monitoring, assessment, and conservation of endangered species and particularly the strengthening of effective management. Studies of (1) a tidal flat in a semi-enclosed embayment, (2) the impact of global climate change on a cold-water ecosystem, (3) coral reefs of Hainan Island and Xisha-Nansha atolls, (4) mangrove forests of the South China Sea, (5) a threatened seagrass field, and (6) an example of stock enhancement practices of the Chinese shrimp fishery are briefly introduced. Besides the overexploitation of living resources (more than 12.4 million tons yielded in 2007), the major threat to the biodiversity of the China seas is environmental deterioration (pollution, coastal construction), particularly in the brackish waters of estuarine environments, which are characterized by high productivity and represent spawning and nursery areas for several economically important species. In the long term, climate change is also a major threat. Finally, challenges in marine biodiversity studies are briefly discussed along with suggestions to strengthen the field. Since 2004, China has participated in the Census of Marine Life, through which advances in the study of zooplankton and zoobenthos biodiversity were finally summarized.  相似文献   

3.
We analyzed the role of the waterways of Belarus in the spread of aquatic exotic invertebrates through the central European invasion corridor. Present day Belarus became critically important when in the end of the 18th—beginning of the 19th century three interbasin canals connecting rivers from the Black and Baltic seas basins were constructed for international trade. These canals became important pathways facilitating the spread of aquatic alien species. For more than a hundred years, only Ponto-Caspian species colonized Belarus using ships and especially timber in rafts exported by Russia into Western Europe. In the second half of the 20th century, new vectors of spread appeared in Belarus, such as stocking of economically important invertebrates and accidental introductions. This paper is the first comprehensive review of aquatic exotic invertebrates in Belarus. Currently, 19 exotic aquatic invertebrates are known in Belarus, including 14 species of Ponto-Caspian origin. The rate of spread of aquatic invasive species in the second half of the 20th century increased 7-fold compared to the 19th—beginning of the 20th century. We found a significant positive correlation between the time since initial invasion and number of waterbodies colonized. We predict a further increase in the rate of colonization of Belarus by exotic invertebrates as well as an increase in the diversity of vectors of spread and donor areas of alien species, especially when the ongoing reconstruction of the interbasin canals will be completed and the hydrological connection between Black Sea and Baltic Sea basins will be reestablished after an interruption that has lasted for almost a century.  相似文献   

4.
Arctic biogeography: The paradox of the marine benthic fauna and flora   总被引:2,自引:0,他引:2  
The marine benthic fauna and flora that inhabit the shallow arctic sublittoral zone comprise a relatively young marine assemblage characterized by species of either Pacific or Atlantic affinity and notably few endemics. The young character of nearshore arctic communities, as well as their biogeographical composition, is largely a product of the Pleistocene glaciation. However, analysis of more recent collections and comparison between the origins of the benthic fauna and flora present some interesting paradoxes to biogeographers. One enigma is the low frequency of algal species with Pacific affinities in the Arctic, especially in the Chukchi, Beaufort and East Siberian Seas of the Eastern Arctic, which receive direct inputs of northward-flowing Pacific waters. In contrast, animal species with Pacific affinities are found throughout the nearshore regions of the Arctic, reaching their highest frequency in the marginal seas between the New Siberian Islands and the Canadian Archipelago. Organization of published and unpublished data, additional field collections, and the use of cladistics and molecular DNA techniques by systematists are a high priority for future research in reconstructing the evolution of the arctic biotic assemblage.  相似文献   

5.
The site of Cessaniti (Vibo Valentia, Italy) has been well known since the 19th century for the richness and good preservation of its Miocene fauna and flora. The sedimentary succession of the site represents a paralic system that evolved toward an open-marine environment recording the Tortonian transgression. The fossil assemblage contains rich invertebrate (corals, bivalves, gastropods, brachiopods, echinoids, benthic and planktonic foraminifers) and vertebrate faunas (proboscideans, rhinoceroses, giraffids, bovids, sirenids, marine turtles, and fish remains). The fossils recovered at the Cessaniti site have a relevant role in phylogenetic studies and paleogeographic reconstructions of Late Miocene environments of the southern Italy. This research is focused on the microstructure and preservation state of the fossil bones. Samples of Metaxytherium sp. bones have been analyzed to understand the diagenetic profile of the bone assemblages that characterizes the taphonomic history of the Cessaniti site. The analyses provided a comprehensive account of how bone mineral (bioapatite) has been altered and demonstrated that the post-burial processes did not significantly affect the micromorphological and biogeochemical features of the bones. The excellent preservation state of the bones strengthens the importance of the Cessaniti site for studies of the Mediterranean Miocene vertebrate fauna.  相似文献   

6.
To study natural polymorphism, pollen grains should be collected from ecologically clean sites. Taking the ecological conditions at the end of the 19th century and at the beginning of the 20th century as more favorable than the modern state, herbarium material (LE) was examined. In addition to typical (normally developed) pollen grains, we found two more morphological types within the range of natural polymorphism of pollen grains of Acer tataricum L. that were produced at the end of the 19th century and at the beginning of the 20th century.  相似文献   

7.
Impacts of climate change on polar seas The polar seas in the Arctic and Antarctic are characterized by extreme cold and the prevalence of sea ice, which provides a unique polar habitat but also strongly affects the pelagic and benthic biota beneath. Life conditions for the marine fauna and flora differ considerably between the Arctic and Southern Oceans, as a result of contrasts in geography, geological history, as well as seasonal dynamics in light regime, sea ice cover and, hence, biological production. Climate change is particularly obvious in the Arctic Ocean and off the Antarctic Peninsula where warming results in a rapid shrinkage of the summer sea ice cover. Such decline threatens the sea‐ice communities and their associated fauna and will also have far reaching effects for the plankton and benthos of the polar seas.  相似文献   

8.
9.
Summary During research on the possible differences between theflora urbica in Padua at the beginning of the century and at present times, a considerable concentration of allergy-provoking species has been observed. In addition to the list of these species, this first approach includes some proposals and comments on the ways of managing public and private green areas.  相似文献   

10.
11.
Abstract

The marine flora of the Isle of Pianosa (Isles Tremiti). – The little Isle Pianosa (Middle Adriatic) presents an algal flora typical for clear, deep seas. Its main components are here described. Endolithic flora on calcareous rocks has been particularly well examined.  相似文献   

12.
Haddock  Steven H. D. 《Hydrobiologia》2004,530(1-3):549-556
Hydrobiologia - The study of the natural history of gelatinous zooplankton (‘gelata’) reached a high point at the end of the 19th century, when scientists first began to understand the...  相似文献   

13.
中国海棘皮动物的种类组成及区系特点   总被引:3,自引:0,他引:3  
廖玉麟  肖宁 《生物多样性》2011,19(6):729-736
棘皮动物是大型底栖动物的重要类群和组成部分.本文从种类组成和区系分布类型两个方面分析了各海区棘皮动物的多样性特点,讨论了温度、海流和水团等海洋环境因素对棘皮动物分布的影响.目前中国海域棘皮动物己记录有591种,包括海百合纲44种,海星纲86种,海胆纲93种,海参纲147种,蛇尾纲221种.黄、渤海和东海、南海的种类组成...  相似文献   

14.
Certain palaeoecological criteria in the reconstruction of the Palaeogene palaeobiogeography of the Indian subcontinent are discussed. The Early Palaeogene is characterised by marine oscillations, a prolific invertebrate fauna, extensive coal facies development and outpouring of basaltic lava flows, the last being a feature connected with the movement of the Indian Plate and coinciding with a Himalayan orogenic impulse. The Middle Eocene transgression marks the transition of marine sedimentation to fluvial conditions in northern India with the presence of a fairly diverse mammalian fauna in northwestern Pakistan and northern India. During the Late Oligocene, mammals clearly ancestral to the much more prolific Siwalik fauna were present in western Pakistan, northeastern India and southcentral Burma.The flora consists of mainly tropical to subtropical families with the addition of some temperate elements in Assam in the latter half of the Eocene and Oligocene. Invertebrates indicate a close affinity between the western and eastern sectors and suggest that the sea was continuous in the north at least up to the Palaeocene. With the emergence of land in the northeastern part of the subcontinent, the fauna of Assam acquired distinct Indo-Pacific elements similar to those of Burma and the Indonesian Arc. Later, the sea was divided into two gulfs which gradually shrank towards the end of the Palaeogene and disappeared by the Middle Miocene.  相似文献   

15.
Large marine regions, including the exceptionally productive Southern Ocean, are iron-limited. As a result, there has been substantial interest in iron-fertilizing high nutrient low chlorophyll (HNLC) areas in an effort to sequester atmospheric carbon dioxide. More recently, research has shifted to quantifying the beneficial effects of iron recycling by marine biota. Marine top predators such as whales and seabirds have been examined specifically in this regard as they have high biomass, form dense aggregations, and excrete bioavailable iron in concentrations seven orders of magnitude higher than ambient seawater. Despite it being well established that marine fauna link the iron and carbon cycles, the connection of this process to the sulfur cycle has rarely been considered. The chemoattraction of specific marine fauna to algal-derived dimethyl sulfide (DMS) is key in triggering dense, multi-species foraging aggregations that induce iron recycling, augmenting carbon assimilation. The goal of this paper is twofold; first, to highlight DMS chemoattraction as a behavior that catalyzes carbon sequestration via natural iron fertilization, and second, to identify knowledge gaps that recent biogeochemical advances can address. Fostering this interdisciplinary research will enhance our understanding of global climate regulation, ecosystem services provided by marine top predators, and the biogeochemical cycles of carbon, iron, and sulfur in HNLC waters.  相似文献   

16.
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.  相似文献   

17.
许再富 《生物多样性》2000,8(1):112-119
根据有关历史资料的统计分析,在元朝以后,滇南各土司向天朝上贡的犀角估算有79~123支,并在清朝于18世纪末19世纪初犀牛就成为濒于灭绝的物种,而最后的一头犀牛是在1957年在滇南被捕杀。滇南各土司在元朝以后向天朝上贡的大象估算有1140~1339头、象牙38~76支,加上大象和犀牛被用于频繁的战争,它在17世纪中期就处于濒危的状态。因而,向天朝上贡这一特殊的人文因素是大象和犀牛在滇南濒危和灭绝的重要原因之一。虽然犀牛已在滇南灭绝,但从现代的生态环境来说,实现再引种是可能的。  相似文献   

18.
In Part I of this examinations, preliminary original researches about the constitutional situations in Germany from the North to the kingdom Württemberg has been presented. In this part II, such preliminary researches follow for the other southern part of the German settlement. With references to Baden, Alsace-Lorraine, and Bavaria first since the second part of the 19th century, comprehensive anthropological data exist, but these contain valuable and differentiated data material. A first analysis for this German data material does not reveal regular relation-ships between body-height, urban and rural life, and geographical altitude. But there are relation-ships between wealthy and poor social classes and between educated and heavily working people, and there exists a negative trend in the body-height-means from the North and South to the middle of the German settlement with minima in Saxony and in several regions in Southern Germany. As spread for the different means about 160 to more than 170 cm is to estimate. The spread seems to be broader in the second half of the 19th century, presumably because the better life-conditions does not hold for all Germans in the same manner. About of the beginning of the 20th century, the body-height-means show an increase with may by interpreted as an kind of rehabilitation after times of emergency in the early industrialization and of difficulties in food supply.  相似文献   

19.
Increasing anthropogenic impacts on biodiversity has been a cause for concern in Australia in recent years. Areas that hold high levels of endemic species and also face exceptional threats of destruction have been described as biodiversity hotspots. Ecological research focused on biodiversity hotspots will provide a better understanding of the flora and fauna of these regions and thus inform conservation strategies. Consequently, it is important to understand where biodiversity hotspots are located and how well they have been researched in the past. However, the choice of ecological research sites may be influenced by a variety of factors such as proximity to research institutions. This study utilized a geographic information system to investigate the spatial distribution of ecological research field sites in Australia and its territorial waters, the hotspots of the field sites around research institutions and the proximity of ecological research field sites from the main campus of the research institutions. Furthermore, these hotspots of ecological research were linked to biodiversity hotspots to identify the regions that were commonly depicted in the ecological literature and to identify others that may need more attention. We demonstrated that hotspots of ecological research were concentrated around research institutions, with a large number of field sites being located between 0 km and 500 km from the nearest institution, especially along the eastern coast. This study highlighted areas that have been the focus of much ecological research as well as areas that need more attention from ecologists to add new knowledge to Australian ecological science.  相似文献   

20.
This study presents the results of phenological observations on arrival and departure terms of some migratory birds on the background of the thermal conditions course of Cracov and its vicinity during the 19th and 20th century. On the base of observations carried out in the years 1944–1978 it was found that some migratory birds had a tendency to change their arrival and departure terms. At the end of this period they were noticed to arrive earlier and to depart later than at the beginning. These differences were more marked when compared with data from the 19th century. In the author's opinion these changes observed in the investigated area during the last decades result from a tendency of a warming up of climate in the Northern Hemisphere.Presented at the Eighth International Congress of Biometeorology, 9–14 September 1979, Shefayim, Israel.  相似文献   

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