甲藻孢囊在辽东半岛沿岸海域表层沉积物中的分布

孢囊是诸多有毒有害甲藻赤潮暴发的种源,也是底栖贝类毒素积累源之一。近年来,北黄海沿岸海域贝毒呈现明显增加的趋势,为掌握有毒有害甲藻在辽东半岛沿岸海域的种源分布情况,笔者于2013年在辽东半岛普兰店(皮口)、庄河、东港浅海海域的菲律宾蛤仔增养殖区域布设12个站位,利用柱状采泥器采集表层沉积物,通过定性和定量分析,研究甲藻孢囊在辽东半岛沿岸海域的空间分布情况,并通过群落相似性分析,研究3个海域甲藻孢囊群落的相似性情况。研究结果显示,3个调查区域共检测出甲藻孢囊10属15种,其中自养型9种,异养型6种。各区域各站位孢囊丰度相差较大,为87~775孢囊/g,平均丰度为393孢囊/g,东港和庄河海域丰度较低,普兰店海域丰度相对较高。相似性分析结果显示,3个海域孢囊群落组成亲缘关系较远。普兰店海域有毒有害甲藻分布广泛,且临近孢囊种类和丰度较高的长山群岛海域,毒素在贝类体内累积的可能性较高,需引起重视。

Distribution of Dinoflagellate Cysts in Surface Sediments along Coasts in Liaodong Peninsula

Cysts are considered as the source of harmful alga blooms and shellfish toxins. Since the shellfish poisoning in the coastal areas of the North Yellow Sea had shown increasing tendency recently,surface sediment samples were collected in the present study by columnar mud collectors from twelve stations in cultivation areas of shellfish along coasts of Pulandian,Zhuanghe and Donggang cities in 2013. Qualitative and quantitative analysis were conducted to investigate the spatial distribution of dinoflagellate resting cysts in these areas. Community similarity analysis were carried out on the cyst communities among three sea areas. The results showed that 15 morphotypes representing 10 genera were identified,among which there were 9 autotrophic species and 6 heterotrophic ones. Cell density of dinoflagellate cyst was ranged from 87 to 775 per gram of dry weight,with the average of 393 cysts/g. Higher abundance of cyst was distributed in Pulandian sea areas,followed by Zhuanghe and donggang sea areas. The cyst communities in the three sea areas showed distant relationships. It is worth noting that it is easier for the accumulation of poisoning in shellfish due to the distribution of toxic cysts in Pulandian and adjacent Changshan archipelago sea areas.