Campanian Climatic Change: Isotopic Evidence from Far East, North America, North Atlantic and Western Europe

Paleoclimatic settings have been reconstructed for the Campanian using original oxygen-isotopic analyses of well-preserved molluskan and foraminifera shells from Russian Far East, Hokkaido, USA, Belgium and some DSDP holes (95, 98, 102, 390A, and 392A) in North Atlantic. Early Early Campanian climatic optimum has been recognized from data on high bottom shelf water paleotemperatures in middle latitudes of both the western circum-Pacific (to 24.2°C) and the eastern circum-Pacific (to 26.4°C) areas and high bottom shallow water paleotemperatures in high latitudes of the Koryak Upland (22.4–25.5°C), which agrees with the data on the Campanian Barykovskaya flora in high latitudes (Golovneva and Herman, 1998) and Jonker flora and its equivalents in middle latitudes. Judging from the data on comparatively high bottom shallow water paleotemperature values in high latitudes, South Alaska (19.4°C) and the Koryak Upland (22.4–25.5°C), we also expect Latest Campanian temperature maximum, which has not been confirmed, however, for low and middle latitudes by neither of isotopic nor paleobotanic data now. Main climatic tendency during the Campanian (with the exception of Latest Campanian) has been learned from isotopic composition of Campanian aragonitic ammonoid shells from the Hokkaido-South Sakhalin (Krilyon) marine basin. In contrary to Huber’s et al. (2002) assumption, we expect warm greenhouse conditions during the most part of the Campanian.     

优质淡水珍珠的体色及其与拉曼光谱的关系

对不同颜色的优质淡水养殖珍珠进行激光拉曼光谱的研究,并试图从中找出珍珠颜色与其中的有机物以及和拉曼光谱的关系。结果发现,和纯白色系列优质珠相比,粉红色系列优质珠多了1134和1526 cm-1两个峰;紫色系列优质珠中的1017,1295,2231,2609 cm-1在纯白色珍珠和粉红色系列中均未曾出现;在有色珍珠中探测到某有机物的拉曼峰:由C—C伸缩振动引起的1121,1134 cm-1及C=C伸缩振动引起的1503,1526 cm-1,推测此有机物为聚乙炔类物质,不同于以前的研究者所认为的类胡萝卜素。不同色系的珍珠,其拉曼光谱有着明显的区别;随着同色系颜色的加深,有机物拉曼谱峰的强度也越来越强。     

Size-differential feeding in Pinna nobilis L. (Mollusca: Bivalvia): Exploitation of detritus,phytoplankton and zooplankton

The endangered fan shell Pinna nobilis is a large bivalve mollusc (<120 cm shell length) endemic to the Mediterranean that lives one-third buried in soft substrata, generally in shallow coastal waters. We hypothesised that P. nobilis of different sizes would ingest different food sources, because small fan shells will inhale material from closer to the substratum than do large fan shells. We studied stomach contents and faeces of 18 fan shells, 6 small (mean 23.0 cm length), 6 medium-sized (mean 41.5 cm length) and 6 large (mean 62.7 cm length) living in a small area of a low-energy coastal detritic bottom characterised by mud, sand and macroalgae at Mali Ston Bay, Croatia. We found that all P. nobilis ingested copious quantities of undetermined detritus (probably at least 95% of ingested material), phytoplankton, micro and mesozooplankton and pollen grains. Large P. nobilis stomach contents showed a preponderance of water column calanoid copepods, while small fan shells had higher numbers of bivalve larvae. All fan shells took in high numbers of harpacticoid copepods that are benthonic, feeding on microbial communities of detritus and benthic vegetation. There was also a significant selection of phytoplankton species, some apparently occurring between inhalation and ingestion. The stomach contents of small P. nobilis had a higher organic matter content than either medium-sized or large fan shells; this indicated that small fan shells ingested detritus of higher organic content than did larger P. nobilis. As the faeces of all P. nobilis had similar organic matter content, this also indicates higher assimilation efficiencies in small fan shells. The demonstration of differential dietary selectivity by different sized animals has implications for future trophic studies of this endangered species. This study also provides the first demonstration of predation on zooplankton by P. nobilis.     

华北地台北缘拴马桩煤系

狼山—色尔腾山和大青山的拴马桩煤系曾被认为是分布于华北地台北缘“内蒙地轴”上的晚古生代纯陆相山间盆地沉积。新的研究证明，上述两地的拴马桩煤系的时代并不完全等同，也不是纯陆相地层，更不是同一盆地的含煤沉积     

唐古拉山侏罗系沉积的若干特征及沉积盆地背景条件的探讨

对于唐古拉山侏罗系沉积类型的不同认识由来已久,然而无论是将其视为地槽型沉积,还是地台型沉积,均难以令人满意地解释该区侏罗纪沉积的特点和性质。 作者在野外工作和室内研究的基础上,从地球化学因素、古生态分析、沉积岩沉积构造和矿物结构成熟度等综合考虑,对该区侏罗纪沉积的特点和性质提出下列证据: （1）含盐度值一般均低于广海的平均盐度值。 （2）发育了海相一半咸水相一陆相的双壳类动物群序列,并以半咸水双壳类属占优势。 （3）沉积构造多为浅水成因的小型波痕,交错层理沉积组合。 （4）沉积岩粒度分析表现了近岸环境的概率曲线特征。 （5）沉积岩矿物结构,成熟度较高,未见海相成因的粒级层理。 结论是唐古拉山区侏罗系应为近岸局限海环境下的沉积产物,在海退时期还发育了滨岸湖相沉积。 根据羌塘地区侏罗纪沉积相空间展布的特点,可以认为唐古拉山区侏罗系仅仅是大西洋型大陆边缘沉积的一个组成部分,是陆架大幅度坳陷所承受的巨厚陆源碎屑沉积,整个羌塘地区侏罗纪沉积在空间上的演替关系及其巨大厚度可借助于大西洋型大陆边缘特有的大陆堤前展沉积模式得到较好的解释。     

莺歌海盆地上新统双壳类贝壳的锶含量及其意义

锶（Ｓｒ）是碳酸盐沉积物及软体动物介壳中的重要微量元素之一,Ｓｒ含量和Ｓｒ／Ｃａ比值的变化明显受沉积相的控制。因此,锶作为地球化学指标具有一定的环境意义。通过对南海北部莺歌海盆地莺６井上新统双壳类贝壳中的Ｓｒ含量和Ｓｒ／Ｃａ比值的变化与环境、成岩作用关系的研究,发现莺歌海盆地上新世沉积环境为上陆坡→潮下带→潮间带,所得结论与双壳类的生态环境和地层沉积相的综合分析结果一致。     

Effects of sewage discharges on lipid and fatty acid composition of the Patagonian bivalve Diplodon chilensis

Lipid and fatty acid (FA) composition and selected oxidative stress parameters of freshwater clams (Dipolodon chilensis), from a sewage-polluted (SMA) and a clean site, were compared. Trophic markers FA were analyzed in clams and sediment. Saturated FA (SAFA), and bacteria and sewage markers were abundant in SMA sediments, while diatom markers were 50% lower. Proportions of SAFA, branched FA, 20:5n − 3 (EPA) and 22:6n − 3 (DHA) were higher in SMA clams. Chronic exposure of D. chilensis to increasing eutrophication affected its lipid and FA composition. The increase in EPA and DHA proportions could be an adaptive response, which increases stress resistance but could also lead to higher susceptibility to lipid peroxidation TBARS, lipofuscins (20-fold) and GSH concentrations were higher in SMA clams. FA markers indicated terrestrial plant detritus and bacteria are important items in D. chilensis diet. Anthropogenic input in their food could be traced using specific FA as trophic markers.     

河北白洋淀全新统沉积特征与地层划分

通过对河北白洋淀老河头剖面全新世沉积物岩性特征、地层层序、粒度组成及微体古生物组合等进行综合研究,重建了白洋淀全新世以来的环境演变过程。全新世以来白洋淀沉积特征所反映的气候环境特征表现为早期开始出现湖沼相沉积,气候寒冷偏湿;中期湖泊沉积发育,气候温暖湿润;晚期湖泊退缩,以河流-沼泽相沉积为主,气候向凉干转变。综合沉积特征、环境演变阶段与加速器质谱(AMS)14C测年资料对白洋淀全新统沉积序列进行系统分析,并将全新统划分为三段:下全新统(11000—8500 a)以灰黄色粉砂质粘土、粉砂为主,夹黑色粘土,冲积-湖沼相沉积发育;中全新统(8500—3200 a)为灰黑色粘土夹粘土质粉砂,湖沼相沉积发育;上全新统(3200 a~)以黄色、褐黄色粉细砂、粘土质粉砂为主,冲积-沼泽相沉积发育。白洋淀全新统中段含有黑色粘土沉积和大量微体与腹足、双壳类等古生物化石,为华北地区全新世地层的划分及区域对比提供了依据。