双齿围沙蚕对潮间带不同类型底质选择行为的研究

利用行为学实验装置研究了双齿围沙蚕(Perinereis aibuhitensis)对低潮区、中潮区和高潮区沉积物表层为10、60 cm深以下的沉积物的选择行为。3个潮区表层为10 cm的沉积物编号分别为1#、2#、3#，3个潮区60 cm以下的沉积物编号分别为4#、5#、6#。结果显示，在实验装置一中，不同沉积物的有机物含量无显著差异(P>0.05)，1#和4#沉积物中，C含量显著高于2#沉积物(P<0.05)，4#沉积物中，N含量显著高于2#和6#沉积物，不同沉积物的H2S含量均差异显著(P<0.05)；1#沉积物间隙水中，H2S含量显著高于其他各组(P<0.05)。规格和底质类型对双齿围沙蚕的选择行为无显著影响(P>0.05)；规格对双齿围沙蚕搜寻时间影响显著(P<0.05)，而底质类型则对搜寻时间无显著影响(P>0.05)。在实验装置二中，6#沉积物中有机物含量显著高于1#和2#沉积物(P<0.05)，C、N含量均显著高于其他沉积物(P<0.05)，2#沉积物中，H2S含量显著高于其他沉积物(P<0.05)；各个沉积物间隙水中H2S含量均差异显著(P<0.05)。底质类型和规格对双齿围沙蚕的移动距离均有显著影响(P<0.05)。研究表明，小规格双齿围沙蚕比较活跃和敏感，倾向于选择H2S含量较低的底质；在底质内部钻蚀时，双齿围沙蚕倾向于选择物质含量较低的底质。总体来看，双齿围沙蚕对自然栖息地底质类型选择性不强。

Experimental Study of the Choice Behavior of Perinereis aibuhitensis Grube among Different Sediment Types

Bioturbation is important for biogeochemical processes of sediments. The associations between bioturbation and changes in sediment environment have been well studied. However, little information is available regarding the behavior of the infauna, which is a major factor affecting sediments. In the present study, sediments at the low, middle, and high tidal zones were collected at different depths (above 10 cm: sediments 1#, 2#, and 3#; below 60 cm: sediments 4#, 5#, and 6#) from the natural habitat of Perinereis aibuhitensis Grube to study their choice behavior in two devices (I and II). The contents of organic matter, carbon, nitrogen, and hydrogen sulfide in different sediment types were also examined. In device I, there was no difference in organic matter contents across different sediments (P>0.05). Carbon contents in sediments 1# and 4# were significantly higher than those in sediment 2# (P<0.05). The nitrogen content in sediment 4# was significantly higher than those in sediments 2# and 6# (P<0.05). The contents of hydrogen sulfide significantly differed across different sediments (P<0.05). Hydrogen sulfide concentration in the pore water of sediment 1# was significantly higher than those of other sediments (P<0.05). Two-way analysis of variance showed that different P. aibuhitensis sizes and sediment types had no significant effects on the choice behavior of P. aibuhitensis (P>0.05). Size affected the time to search for different sediments (P<0.05), while sediment type showed no effect on search time (P>0.05). In device II, the content of organic matter in sediment 6# was significantly higher than those of sediments 1# and 2# (P<0.05). The contents of carbon and nitrogen in sediment 6# were significantly higher than those in other sediments (P<0.05). The content of hydrogen sulfide in sediment 2# was significantly higher than that in other sediments (P<0.05), and hydrogen sulfide concentrations in pore water significantly differed among different sediments (P<0.05). Two-way analysis of variance showed that different P. aibuhitensis sizes and sediment types significantly affected the movement distance of P. aibuhitensis (P<0.05). Moreover, small P. aibuhitensis were more active and sensitive and preferred sediments with lower hydrogen sulfide content. When P. aibuhitensis drilled inside the sediment, they tended to choose sediments with lower organic matter content. In general, P. aibuhitensis exhibited a slight selectivity for different natural sediment types.