中国海域斑海豹种群资源和分子遗传特征研究

斑海豹，西北太平洋广泛分布的冷水性海洋哺乳动物，为我国的二类保护野生动物，属于濒危物种，也是唯一能在我国海域自然繁殖的鳍脚类动物。辽东湾结冰区是斑海豹在世界上8个繁殖区中最南端的一个。为了能够更好地保护斑海豹资源，对渤海海域斑海豹的栖息地、种群动态及分布时间、重金属体内积累、以及斑海豹的分子遗传特性进行了研究。结果如下： 斑海豹在渤海海域的栖息地有辽宁双台子河口水域、大连虎平岛和山东庙岛群岛海域三处，其中的上岸点分别为河口泥沙滩、海里的浅石滩和海岛周围的小岛礁三种类型。斑海豹出现在三个栖息地的时间为每年的3~5月，2002~2008年间各栖息地的斑海豹的数量变化不明显。 对斑海豹肌肉、肝和肾脏组织重金属元素含量的分析结果显示，汞（Hg）、镉（Cd）、铅（Pb）和砷（As）等有毒元素在斑海豹体内的积累远未达到致死浓度。 对斑海豹的部分mtDNA 序列分析发现，辽东湾斑海豹群体的遗传距离、控制区DNA的单元型多样度和核苷酸多样度均远小于日本群体，辽东湾群体的遗传多样性水平较低。 微卫星引物标记对辽东湾斑海豹群体的遗传多样性研究显示，平均有效等位基因数（2~4个）和期望杂合度（0.24~0.72）等指标均较低，表明辽东湾斑海豹群体遗传多样性水平下降，可能曾出现过一定程度的瓶颈效应。 对斑海豹的41个MHC-I基因的序列分析，得到40个等位基因。斑海豹MHC-I基因多态性水平高，说明辽东湾斑海豹种群MHC-I基因的丰富性。 以上研究结果对于我国辽东湾斑海豹种群的保护和管理具有一定意义。

Ecological environment changes in Daya Bay, China, from 1982 to 2004

Data collected from 12 marine monitoring stations in Daya Bay from 1982 to 2004 reveal a substantial change in the ecological environment of this region. The average N/P ratio increased from 1.377 in 1985 to 49.09 in 2004. Algal species changed from 159 species of 46 genera in 1982 to 126 species of 44 genera in 2004. Major zooplankton species went from 46 species in 1983 to 36 species in 2004. The annual mean biomass of benthic animals was recorded at 123.10 gm(2) in 1982 and 126.68 g m(2) in 2004. Mean biomass and species of benthic animals near nuclear power plants ranged froth 317.9 g m(2) in 1991 to 45.24 g m(2) in 2004 and from 250 species in 1991 to 177 species in 2004. A total of 12-19 species of hermatypic corals and 13 species of mangrove plants were observed in Daya Bay from 1984 to 2002. 2008 Elsevier Ltd. All rights reserved.

Dynamics of intraseasonal sea level and thermocline variability in the equatorial Atlantic during 2002-03

Satellite and in situ observations in the equatorial Atlantic Ocean during 2002-03 show dominant spectral peaks at 40-60 days and secondary peaks at 10-40 days in sea level and thermocline within the intraseasonal period band (10-80 days). A detailed investigation of the dynamics of the intraseasonal variations is carried out using an ocean general circulation model, namely, the Hybrid Coordinate Ocean Model (HYCOM). Two parallel experiments are performed in the tropical Atlantic Ocean basin for the period 2000-03: one is forced by daily scatterometer winds from the Quick Scatterometer (QuikSCAT) satellite together with other forcing fields, and the other is forced by the low-passed 80-day version of the above fields. To help in understanding the role played by the wind-driven equatorial waves, a linear continuously stratified ocean model is also used. Within 3 degrees S-3 degrees N of the equatorial region, the strong 40-60-day sea surface height anomaly (SSHA) and thermocline variability result mainly from the first and second baroclinic modes equatorial Kelvin waves that are forced by intraseasonal zonal winds, with the second baroclinic mode playing a more important role. Sharp 40-50-day peaks of zonal and meridional winds appear in both the QuikSCAT and Pilot Research Moored Array in the Tropical Atlantic (PIRATA) data for the period 2002-03, and they are especially strong in 2002. Zonal wind anomaly in the central-western equatorial basin for the period 2000-06 is significantly correlated with SSHA across the equatorial basin, with simultaneous/ lag correlation ranging from-0.62 to 0.74 above 95% significance. Away from the equator (3 degrees-5 degrees N), however, sea level and thermocline variations in the 40-60-day band are caused largely by tropical instability waves (TIWs). On 10-40-day time scales and west of 10 degrees W, the spectral power of sea level and thermocline appears to be dominated by TIWs within 5 degrees S-5 degrees N of the equatorial region. The wind-driven circulation, however, also provides a significant contribution. Interestingly, east of 10 W, SSHA and thermocline variations at 10 40- day periods result almost entirely from wind-driven equatorial waves. During the boreal spring of 2002 when TIWs are weak, Kelvin waves dominate the SSHA across the equatorial basin (2 degrees S-2 degrees N). The observed quasi-biweekly Yanai waves are excited mainly by the quasi-biweekly meridional winds, and they contribute significantly to the SSHA and thermocline variations in 1 degrees-5 degrees N and 1 degrees-5 degrees S regions.