162 resultados para Xinjiang Uygur Zizhiqu (China)--History--Sources


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Bangia fuscopurpurea (Rhodophyta) was cultivated in Putian (Fujian province, China). The characteristics of the life history concerned with cultivation were investigated and the cultivation procedure was presented. The gametophytic phase (thallus) and the sporophytic phase (conchocelis) occurred alternately in the life history of B. fuscopurpurea. Young thalli produced archeospores, and the number depended on the environmental factors. Temperature affected the number of archeospore release and percent of germination, and photo flux density (PFD) mainly affected the time of spore release and germination. Thalli matured from December to February and developed into the conchocelis phase through sexual reproduction. The conchocelis grown in shells had three developmental stages: vegetative conchocelis, conchosporangiall formation and conchospore formation. Pit-connections were present in the first 2 stages but absent after conchospore formation. Vegetative conchocelis and conchosporangial. branches can transform into each other. However, conchospores only developed into the gametophytic phase. Cultivation of B. fuscopurpurea was based on characterization of the life history, consisting of 3 steps: zygotospores collection, indoor cultivation of conchocelis and outdoor cultivation of thalli. Young thalli that developed from conchospores produced numerous archeospores before December. Over 90% of the crop was from the development of archeospores. The results indicated that conchosporelings were a good source of archeospores, and the development of the large quantity of archeospores acted as a more prevailing means to increase the population size. (C) 2008 Elsevier B.V. All rights reserved.

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This paper provides basic information on the general ecology and life history cycles of various flatfish species in the Bohai Sea, China. The species studied are Paralichthys olivaceus (Temminck & Schlegel), Cleisthenes herzensteini (Schmidt), Eopsetta grigorjewi (Herzenstein), Verasper variegatus (Temminck & Schlegel), Pleuronichthys cornutus (Temminck & Schlegel), Pseudopleuronectes yokohamae (Gunther), Pseudopleuronectes herzensteini (Jordan & Snyder), Kareius bicoloratus (Basilewsky), Zebrias zebra (Bloch), Cynoglossus semilaevis Gunther, Cynoglossus abbreviatus (Gray) and Cynoglossus joyneri Gunther. Information on reproduction, eggs and larval distribution, growth and adult abundance is presented. Based on the biology and ecology of these flatfish, artificial enhancement of the commercial species in the Bohai Sea is discussed.

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The composition and distribution of aliphatic (n-alkanes) and polyaromatic hydrocarbons (PAHs) were measured for the surface sediments collected at 25 sites from Jiaozhou Bay, Qingdao, China. Total n-alkanes and PAH concentrations ranged from 0.5 to 8.2 mu g/gdw and 0.02 to 2.2 mu g/gdw, respectively, and the distribution of both n-alkanes and PAHs showed large spatial variations in the bay. The distribution of PAHs in the sediments was predominated by the three or more ring compounds. High hydrocarbon levels were generally found in the areas associated with high anthropogenic impact and port activities in the bay. The calculated hydrocarbon indexes suggest that petroleum contamination was the main source of n-alkanes, while both pyrolytic and petrogenic sources contributed PAHs to the surface sediments of Jiaozhou Bay. In comparison to other polluted coastal sediments, the level of contamination from both aliphatic hydrocarbons and PAHs in Jiaozhou Bay sediments is relatively low at the present time. (c) 2005 Elsevier Ltd. All rights reserved.

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Food Sources of three filter-feeding bivalves from two habitats (intertidal oyster Crassostrea gigas, mussel Mytilus galloprovincialis. and subtidal cultured scallop Chlamys farreri) of Jiaozhou Bay (Qingdao,China) were determined by fatty acid and stable isotope in analysis. Cultured scallop was characterized by significant diatom markets such as 16:1/16:0 close to 1 and high ratio of 20:5(n - 3)/22:6(n - 3), hence we assume that the scallop mainly feeds on diatoms. Fatty acid biomarkers specific to bacteria and terrestrial materials were also found in considerable amounts in scallop tissue, which suggested that there were Substantial bacterial and terrestrial input into the food of the species. Intertidal oyster and mussel, however, exhibited significant flagellate marker. 22:6(n - 3). and lower level of diatom markers. which indicated that flagellates are also part of intertidal bivalves' Planktonic food Sources: meanwhile, high level of Chlorophyta fatty acid marker, Sigma 18:2(n - 6) + 18:3(n - 3), suggested that Ulva pertusa (Chlorophyta) seaweed bed supplied important food sources to intertidal bivalves. Additionally, result of stable isotope analysis showed that phytoplankton contributed 86.2 to 89.0% to intertidal bivalves' carbon budget; macroalga U. pertusa origin source had a contribution of MIX, to 11.0%, which indicated its role Lis in important supplemental food source to intertidal bivalves. From this study. it is concluded that the dietary difference of three bivalves probably relates to the different potential food sources in the scallop farm and intertidal zone in Jiaozhou Bay.

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In the present paper, we have elucidated the importance of energy and water cycling in arid areas to investigate global climate and local economics. Then, we were concerned with the physical arguments as how to stratify the soil, and the stability of the numerical scheme in the mathematical model for predicting temperature variation and water motion. Furthermore, we discuss the methods to estimate evaporation in arid areas. Numerical simulation of energy and water cycling at the Acsu Observatory, CAS, Xinjiang province and Shapuotou Observatory, CAS, Ningxia Province are conducted as case studies. The results show that the laws of terrestrial processes are rather typical in these arid areas. Planting drought-endurable trees can alleviate unfavourable conditions to a certain extent. (C) 1997 Academic Press Limited.