Cytochrome P450 differences in normal and imposex-affected female whelk Buccinum undatum from the open North Sea

Normal and imposex-affected female Buccinum undatum were sampled from the open North Sea at three locations, one with low, and two with high shipping densities. Cytochrome P450 components and P450 aromatase activity were determined in the microsomal fractions isolated from pooled digestive gland/gonads. Cytochrome P450 aromatase activity was significantly higher (P < 0.05) in normal females collected in the low shipping density area (1,325 +/- 295 fmol/h/mg protein) than levels from imposex animals from a high shipping density area (620 +/- 287 fmol/h/mg protein). A negative correlation was found between aromatase activity and organotin body burden (r = -0.99). Levels of CYP450, cytochrome b5 and NADPH cytochrome c reductase activity did not show differences among groups. This is the first field evidence of depressed aromatase activity in imposex affected females, although additional research under laboratory controlled conditions is required to fully understand the mechanisms underlying the development of imposex in this species.     

通过对重力波曳力的参数化来减小数值天气预报和大气环流模式中的系统性误差

一、引 言 由于地形性激发的中尺度重力波的中断,在加拿大气候中心大气环流谱模式中有时候采用了波的曳力效应的参数化。这一参数化的细节以及它在大气环流模式气候模拟中影响的讨论,可见Boer等人(1985)的工作。 最近,人们利用激发重力波次尺度地形的更好的描绘,来修改这一参数化方案。还有,使用Lindzen(1981)的波饱和概念来描述曳力效应。这一关于地形重力波曳力参数化的作法已在加拿大气候中心的大气环流谱模式中广泛试验,在加拿大气象中心的业务的谱数值预报模式中也正在普遍进行试验。本文的目的所在于概述在这些模式中正在普遍使用的波的曳力方案,并且证明这一方案在消除中期预报和大气环流模拟的系统性误差方面的用处。     

海南岛珊瑚礁的主要类型

一、前言 中苏海洋生物考察团,于1958年3—6月在中国南海的海南岛进行了考察工作,对该地区的海洋潮间带动物群的栖息条件和沿岸的动物生态学进行了调查研究。工作中除考察了岩石、红树丛、沙滩及泥滩的生物群落外,同时考察了热带海洋中典型的生物群落——珊瑚礁。     

黄海多毛类动物地理学的初步研究

1.黄海多毛类区系包含有中国沿岸特有地方性种,黄海和日本沿岸的特有地方性种,广温性热带暖水种,寒温带冷水种和广布种等不同性质成分。 2.值得提出的是太平洋东西两岸种在黄海的发现,计有19种。这些种的分布应该考虑不仅是由于历史的成因,在某种程度上幼体也许有可能随当前自日本沿岸流向美洲沿 岸的黑潮传布过去。多毛类有些种幼虫期很长,并且能随海流分布至深海(Thorson,1950)。 3.根据与邻近海区区系的比较,黄海多毛类与日本沿岸,特别是日本本州北部金华山附近的女川湾和松岛湾一带的区系最相近似,女川湾和松岛湾一带属亲潮寒流和黑潮暖流交汇区,因之在种类组成上不仅有来自南方的暖水种,同时,还有北方的冷水种,具有混合区系特征。黄海——本州北部应属同一地理区划。 4.黄海多毛类具有十分显著的混合区系特征,与日本的情况不同,黄海的暖水种多分布在潮间带,冷水种大部分在较深水域,井与深水区终年存在的冷水团有关。 5.黄海北部和中部应属北太平洋北温带和印度西太平洋热带区之间的过渡区。     

Macrofauna impact on Ulva rigida C. Ag. production and relationship with environmental variables in the lagoon of Venice

The grazing pressure of the macrofaunal invertebrates associated with the biomass of Ulva rigida in the Venice lagoon, their species composition and relationship with environmental variables have been studied. Fifteen sampling campaigns were carried out during different seasons both in the central basin of the lagoon, dominated by macroalgae (especially U. rigida C. Ag.) and in the southern basin, prevalently populated by seagrasses (especially Zostera marina L.). Replicate experiments were conducted in the field by exposing Ulva fronds in net cages of 10 and 1 mm (control) mesh-sizes to allow or prevent grazer entrance. The grazing pressure was determined as Ulva growth rate difference in the cages. In the absence of invertebrate herbivores, Ulva exhibited per cent relative growth rates (%RGRs) ranging from 1.5 to 9.5% day(-1), whereas in their presence the %RGRs were significantly lower (from -2.5 to 3.4% day(-1)) and frequently negative, especially in the station dominated by macroalgae. In this area, peak grazing rates and macrofauna biomasses of up to 8.6% day(-1) and 1,480 g m(-2) fwt (84.4 ash-free dry weight), respectively, were found. On the whole, during in field experiments in the Ulva-dominated station, herbivores removed an amount of biomass whose percentage ranged from 59 to 165% (mean: 103%) of the biomass yield (grazers excluded) found in the cages. These results suggest the possibility that grazers could act as an important factor affecting Ulva production in the Venice lagoon. Macrofauna populations were analysed by means of multivaliate techniques applied to biological variables only and biological and environmental variables together. Data of individual abundance, after a log(x + 1) transformation and the calculation of the Bray-Curtis matrix, were classified using the Cluster Analysis and ordinated by means of the Non-Metric Multidimensional Scaling (MDS) technique, in accordance with the strategies used in the study of multispecies distributions. Finally, biological and environmental variables were analysed together by means of correlation matrices and the Principal Component Analysis.     

Variational iteration solving method for El Nio phenomenon atmospheric physics of nonlinear model

1 IntroductionThe El Ni’o atmospheric physics oscillation is anabnormal phenomenon involved in the tropical Pacificocean- atmosphere interactions. Studies on the El Ni(ophenomenon are very attractive (Lin et al., 2000; Linet al., 2001, 2002; Wang, 2001; Feng et al., 2001;Feng et al., 2002; Liu et al., 2002; Wei and Chen,2003; Xie et al., 2002; Zhu et al., 2002; Pu et al.,2003; Gu et al., 2004; Yu and Liu, 2004). Lin and Mo(2004), Mo and Lin (2004) and Mo et al. (2004) alsostudied a s…     

应用C14测定浮游生物初级生产力的方法

本文从单位时间和单位体积内通过光合作用转变为有机碳的重量出发,介绍了一个测定有机物初级生产力的新的海洋学方法。为了使对此感兴趣的人都能够参照他们各自的需要来应用或改进这一同位素定量方法,我们简短地对操作方法和历史作了一般的评价之后,还作了相当详尽的叙述。     

海岸带泥砂运动的形态学与岩石学的研究方法

在苏联,近十年来,海岸地貌学的研究有了很大的发展,而对于海岸地带,即海与陆相互作用地带的泥砂运动及其迁移规律性的研究则是其中最重要的一个方向。实际上,正像所指出的,对岩石圈物质迁移过程的研究是从“岩石颗粒及原生岩塊的破碎开始直到它们在地质作用中重新结合为止”而且是作为研究地壳表面地形的形成及共发展的地貌学中的一个重要任务。正是在这个作用的过程中及其后果,就建立着并发展着各种地形的形态。通常,这些形态可划分为二种基本类型:剥蚀的和堆积的。     

海洋微生物学的主要任务

海——微生物栖息的特殊环境。特殊的盐类成分,低温,高压,低浓度的有机物质,植物及动物区系的稀少等组成了微生物生命活动的广阔海洋区域一些主要生态特征。 海洋中最初的微生物学研究,早在上一世纪就已进行了,但足它们局限于较狭小的任务——     

东海东北海域环流的数值研究

本文用二维正压非线性模式研究东海东北海域(包括朝鲜海峡)的流型。该海域的环流主要为海底地形所支配。科氏效应对环流的变动很重要,β效应则是次要的。作为研究该海域的第一步,风应力未予考虑。该海域的海流在夏季比冬季强,朝鲜海峡一带尤为明显,这与所观察到的对马海流输运的年变化是一致的。在附录中导出了带底应力的应涡守恒方程,并用以分析该海域东北和东南部的流场,以便与数值结果进行比较。