秦皇岛砂滩海洋线虫的数量研究

A STUDY ON THE ABUNDANCE OF FREE-LIVING MARINE NEMATODES ON FOUR INTERTIDAL SANDY BEACHES AT THE QIN HUANG DAO BAY, NORTH CHINA

在两年的周期内,对秦皇岛4个砂滩的海洋线虫进行了6次芯样采集。灯塔、新煤码头、汤河口和北戴河赤土山4个砂滩均系分选好的细砂或中细砂,其中值粒径为140-285μm。对连续16个芯样计数的变异性所做的测试证明,1,2和3个芯样计算所得95％C.L.分别是0.539X—1.855X,0.647X—1.547X和0.700X—1.428X。秦皇岛砂滩海洋线虫的年平均密度:中潮带上区为1381±441 inds.10cm^(-2)。中潮带下区为1264±538 inds.10cm^(-2)。灯塔和新煤码头砂滩,8月出现高密度值,与温度的季节变化相符合,而汤河口则出现最低值,可能与污染物的大量排出有关。多数砂滩的大部分芯样显示了明显的重直分布,即种群数量的大部分集中在芯样顶部的两个分层:0～4和5～8cm。没有发现垂直分布的季节变化趋势。与世界其他海区砂滩的资料进行了比较。

Free-living marine nematodes were studied over a 2-year period on four sandy beaches at the Qin Huang Dao Bay,Hebai province.The four sices investigated (the Light-house,the New Coal Pier,the Tang River Estuary and the Chi Tu Shan) were well sorted sand and fine sand,with median diameter from 140μm to 285μm To determine the variability of samples counts,16 replicate cores of 2.2 cm internal diameter were collected from the area of MTL at Tang River Estuary.The 95% confidence limits (C.L.) for the total population was calculated after a log transformation.The 96% C.L.of a single core,and that of the mean of two and three cores were as follows:0.539X-1.855X,0.647X-1.547X and 0.700X-1.428X respectively.Total nematodes abundance averaged 1381±441 inds.10cm-2 at the upper layer of MTL and 1264±538 inds 10cm-2 at the lower layer of MTL.There was no significant difference between them.The numerical difference of nematodes in the four beaches was also not significant.Most of the cores showed marked vertical distributions,i.e.the bulk of the nematode population concentrated in the top 0-8cm sediment.Maximum densities occurred at the time of highest temperatures at the Ligh-house and the New Coal Pier beaches.Minimum abundance was observed at the same time in the Tang River Estuary beach,possibly due to the pollutants from the River.The seasonal changes of the vertical distributions were not observed.The abundance reported here has been compared with those reported from similar sandy beaches all over the world.