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31.
《Journal of Natural History》2012,46(13-14):911-947
In this paper, soft-bottom polychaete species collected in August and September 2011 in the Aegean and Levantine Seas (4–325 m) are presented. A total of 358 species belonging to 48 families were found. Two species, Leonnates aylaoberi sp. nov. and Levinsenia materi sp. nov., are new to science and 14 species are new records for the marine fauna of Turkey. Syllidae and Spionidae were represented by a high number of species. The highest polychaete density was estimated as 5660 ind.m?2 in the area. The most dominant species in the area were Lumbrineris geldiayi, Owenia fusiformis and Sigambra tentaculata. A total of 21 alien polychaete species were encountered in the area, of which Streblospio gynobranchiata formed a dense population in the Aegean Sea (Izmir Bay), and Prionospio depauperata and Prionospio saccifera in the Levantine Sea. Four hot spot areas for the settlement of alien species were determined in the area. http://www.zoobank.org/urn:lsid:zoobank.org:pub:4ECEC9B2-1604-4768-B152-BBEAE257249F 相似文献
32.
《Journal of Natural History》2012,46(29-30):1761-1778
This paper introduces new data on Todaropsis eblanae morphology, morphometry and functional aspects of the male reproductive system and hectocotylus. Spermatophores differ in specimens from the Atlantic Ocean (average length, 18.28 ± 1.45 mm, 15.63 ± 0.8% of mantle length; weight, 2.0–12.0 mg) and the Indian Ocean (average length, 24.8 ± 2.85 mm, 16.9 ± 2.1% of mantle length; weight, 35.0–39.6 mg) (t?=?3.14; p < 0.01 for absolute sizes and t?=?0.711; p > 001 for relative sizes). An additional important distinctive trait is the form of connection of the cement body with the ejaculatory tube. In recent years, T. eblanae has been regularly caught in the Barents Sea, meaning its range has extended to subarctic waters. The morphology and morphometry of the spermatophoric complex of organs did not vary in investigated parts of its range. Hectocotylus patterns and some important spermatophore traits distinguish Todaropsis from other Ommastrephidae. 相似文献
33.
《Journal of Natural History》2012,46(17):2145-2152
During a recent biological investigation of submarine caves of Grand Cayman, the Caribbean Sea, two species of Heteromysoides were collected. One species, referred to Heteromysoides spongicola B?cescu, 1968, is known only by the type specimens; therefore, this discovery marks the second record of occurrence and a new habitat record for the species. The other species is considered new and is described as H. stenoura, a 10th species of the genus. The new species closely resembles H. simplex Hanamura and Kase, 2001, known from the submarine caves of Okinawa, north-western Pacific, in the possession of a spiniform process on the eyes and a simple termination to the third thoracic endopod. However, the new species can be readily distinguished from the Pacific congener by a distally narrow telson and a more developed cornea in the eyes. 相似文献
34.
分析了黄海沿岸地区环境污染的时间变动,指出近10年来工业废水排放已经呈现下降趋势,环境与经济发展基本相互协调,统计分析证明:该地区环境污染程度与经济发展呈现典型的正相关关系,符合工业化中期的典型特征:人均GDP、水资源的消费强度、人口增长均对工业废水的排放起到了促进作用。 相似文献
35.
肖嗣荣 《河北省科学院学报》1990,(2)
本文对河北平原旱涝与北太平洋海温距平之间关系进行了研究,发现东太平洋赤道区和黑潮区海温异常分布对河北旱涝影响最为显著。基于统计分析结果,本文提出了北太平洋海温异常对河北平原旱涝影响的可能途径。 相似文献
36.
37.
针对埕岛油田的实际情况,提出了测井多并分析技术,主要包括对测井数据进行标准化处理,以测井曲线为基础进行岩心的深度归位及测井曲线校正.通过油田10多口井资料的分析和处理,并以埕北102、201和斜2井计算的孔隙度、渗透率、泥质含量和含水饱和度数值与岩心分析值相对比,说明了上述分析方法和处理技术的有效性和实用价值. 相似文献
38.
Radiolarian record to paleoecological environment change events over the past 1.2 MaBP in the southern South China Sea 总被引:2,自引:0,他引:2
This note studies the Radiolarian fossil groups since 1.2 MaBP in ODP leg 184 site 1143, the southern South China Sea (SCS).
The result shows that radiolarian abundance experienced a significant variation: before 0.9 MaBP it remained at the extremely
low level, but increased with low extent between 0.9–0.65 Ma, which corresponded to the Mid-Pleistocene Transition stage,
and it increased rapidly after 0.65 MaBP. During the whole process, the average abundance became higher and higher in each
stage, and showed regularly periodic fluctuations. The obvious increase after 0.65 MaBP is inferred to result from the enhanced
upwelling in this region, which was induced by the intensified monsoon circulation after the “Mid-Pleistocene Transition”.
An outstanding result of the spectral analyses is that a long oscillation of ∼ 0.2 Ma cycle was found in the records of radiolarian
abundance and complex diversity, which corresponds well to the result of other paleoceanographic indexes. This probably indicated
a special cycle characteristic of paleoecological environment evolution in this area. In addition, all of the radiolarian
indexes show an obvious boundary in about 0.47 MaBP, indicating the abrupt variation of the community structure and radiolarian
abundance level before and after 0.47 MaBP. So we suppose that there existed a distinct change event of oceanic ecology environment
during that period. 相似文献
39.
Carbon isotopic record of foraminifers in surface sediments from the South China Sea and its significance 总被引:3,自引:0,他引:3
CHENGXinrong WANGPinxian HUANGBaoqi LIUChuanlian JIANZhimin ZHAOQuanhong LIJianru TIANJun XUJian 《科学通报(英文版)》2005,50(2):162-166
Since the 1990s, the papers and data involved withthe South China Sea (SCS) have been emerging in largenumbers in the world as people pay more attention to thepaleoceanography of the SCS. There have been more than100 cores mentioned in papers containing p… 相似文献
40.
Linear sand ridges on the outer shelf of the East China Sea 总被引:3,自引:1,他引:3
WU Ziyin JIN Xianglong LI Jiabiao ZHENG Yulong WANG Xiaobo 《科学通报(英文版)》2005,50(21):2517-2528
Based on the latest full-coverage high-resolution multi-beam sounding data, the distribution of the linear sand ridges on the outer shelf of the East China Sea (ECS) is studied with quantitative statistical analysis. The study area can be divided into the northeastern part and the southwestern part. Sand ridges in the northeastern area, trending 116°N, show obvious linear character and shrink to the inner shell Sand ridges in the southwestern area, trending 120°N -146°N, tend to have net form. Sand ridges gradually become sand sheets in the center part of study area. Sand ridges are distributed landward to the isobath of 60m, distributed seaward to the water depth of 120 m in the northeast and 150 m in the southwest. Immature sand ridges are observed at water depth of 130-180 m in the southwestern depressions. The acoustic reflection properties of the internal high.angle inclined beddings of the sand ridges are analyzed based on the typical seismic profiles close to the research area. Lithological analysis and dating of 4 boreholes and 12 cores indicate that the widely distributed transgressive sand layer with high content of shell debris which was formed in the early-middle Holocene is the main composition of the linear sand ridges on the outer shelf of the ECS. The dominating factor in formation, developing and burying of the sand ridges is the variation of water depth caused by sealevel change and the rate of sediment supply. In 12400 aBP the cotidal lines of the M2 tidal component were closely perpendicular to the strike-directions of the sand ridges in the study area, and the tidal wave system during 12000-8000 aBP might play a key role in the formation of the linear sand ridges which are widely distributed on the outer shelf of the ECS. 相似文献