In July (summer) and October (autumn) 2007 and in January (winter) and April (spring) 2008, an investigation was made on the spatiotemporal distribution of virus in the surface seawater, overlying water and sediment in Xiangshan Bay. A cylindrical High-fidelity gravity sampler instead of conventional grab sampler was used for collecting samples, and principal component analysis and multivariate linear stepwise regression analysis were adopted to analyze the relationships between virus abundance and environmental parameters. Virus abundance during investigation ranged from 6.48× 104 to 1.01 × 108 cells/mL, with a mean of 1.55×107, 1.03×108, 1.13 ×108 cells/mL of the surface seawater, overlying water and sediment respectively. Significantly high values could be observed for virus abundance in autumn compared to other sampling time with the lowest value in winter. In vertical direction, the number of viruses in the overlying water and in the sediment was higher than that in the surface seawater; in horizontal direction, the number of viruses decreased from the top to the mouth of the bay with higher abundance near the breeding areas. A very high value of virus abundance was observed near Power Plant as well. Such spatial distribution of viruses in Xiangshan Bay demonstrated that anthropogenic coastal land pollution and maricultures pollution played the key roles. The dissolved oxygen, surface seawater temperature and Ch1 a were the main factors influencing the abundance marine virus in surface seawater. In contrast, the nutrients (N,P) and bacteria abundance were the main factors influencing virioplankton distribution in the overlying water; in addition,the virus abundance had significant positive relation with the bacteria abuntance in the sediment (P ＜0.01).%分别于2007年的7月(夏季)、11月(秋季)与2008年的1月(冬季)、4月(春季)采集样品,研究了象山港海域的水样(表层海水和上覆水)中的浮游病毒及沉积物中的底层病毒丰度的时空分布特征,并采用主成分分析及多元逐步回归分析方法研究了影响浮游病毒丰度时空分布的主要因素,结果表明,调查期间象山港海域表层海水、上覆水及沉积物样品中浮游(底层)病毒丰度实测值的变化范围为6.48x104～1.01x108cells/mL,均值分别为1.55x107,1.03x108,1.13x108cells/mL.季节分布特征为秋季>夏季>春季>冬季.病毒丰度垂直分布表现为上覆水均大于表层海水;平面分布均为从港底到港口递减、养殖区高于非养殖区、电厂附近海域出现较高值的趋势.近岸人类活动的陆源污染及水产养殖污染是造成此空间分布特征的主要原因.溶解氧、水温及叶绿素a是制约表层海水浮游病毒丰度的主要影响因素;营养盐含量及浮游细菌丰度是制约上覆水中浮游病毒丰度的主要影响因素,沉积物中的病毒丰度与细菌丰度具有显著正相关性(P<0.01).
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