Microphytobenthos seasonality determines growth and reproduction in intertidal bivalves
Microphytobenthos seasonality determines growth and reproduction in intertidal bivalves
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DOI：
10.3354/meps315113
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发表时间：
2006-06
影响因子：
2.5
通讯作者：
C. Kang;Yong-Woo Lee;E. Choy;Jae-Ki Shin;In-Soo Seo;Jae-Sang Hong
中科院分区：
文献类型：
--
作者：
C. Kang;Yong-Woo Lee;E. Choy;Jae-Ki Shin;In-Soo Seo;Jae-Sang Hong
2002年1 - 12月，在韩国光阳湾温带河口泥质滩涂研究了潮间带双壳类动物的食物来源浮游植物和微底栖植物生物量的年循环。研究了悬浮饲养的marilina laterula和沉积饲养的rutila Moerella的生长和繁殖活动的季节变化规律，并结合双壳类动物组织的δ 13c和δ 15n及其潜在食物资源的分析，探讨了它们与中上层和底栖微藻年循环的关系。浮游植物和微底栖植物生物量在春末-夏季达到峰值，呈单峰型季节变化。水体和沉积物的光合色素组成均以硅藻标志色素岩藻黄质为主。浮游微藻和底栖微藻的年循环模式相似，分类组成相似，表明重悬浮的底栖微藻是海湾浮游植物组成的重要贡献者。该结论与渤海湾悬浮颗粒物（POM）的δ 13c值和海湾的物理特征有关。在叶绿素a （chl a）浓度最高的春末和夏季，这两种双壳类动物的生长和繁殖活动都是同步的：它们的外壳和组织生长以及性腺发育都是同时完成的。这种大型动物和微藻过程的时间耦合表明潮间带双壳类的活动可能在很大程度上取决于微底栖植物的季节性。尽管浮游植物对悬浮食性双壳类的饮食有相当的贡献，但双壳类组织的同位素特征表明，它们对微底栖植物来源的有机质的依赖与季节无关。这些结果强调了在悬浮和沉积双壳类动物配子产生和生长的关键时期，作为一种可用食物来源的小底栖植物的季节性发育的重要性。
The annual cycles of phytoplanktonic and microphytobenthic biomasses as food sources for intertidal bivalves were investigated in a temperate estuarine muddy sandflat of Kwangyang Bay (Korea) from January to December 2002. Seasonal patterns in growth and reproductive activity of a suspension-feeder Laternula marilina and a deposit-feeder Moerella rutila were examined in order to assess their relationship with the annual cycles of pelagic and benthic microalgae, and were com- bined with analyses of δ 13 C and δ 15 N of bivalve tissues and their potential food resources. Biomasses of phytoplankton and microphytobenthos peaked in late spring-summer, and demonstrated a uni- modal pattern of seasonal variation. Photosynthetic pigment composition showed a predominance of diatom marker pigment, fucoxanthin, in the water and the sediments throughout the year. Similar patterns of annual cycles in pelagic and benthic microalgal biomasses and similarities in taxonomic composition indicated that resuspended microphytobenthos is an important contributor to the bay's phytoplankton component. This was supported by the δ 13 C values of suspended particulate organic matter (POM) and physical characteristics of the bay. Synchrony in growth and reproductive activity was observed for both bivalves: their shell and tissue growth and gonadal development were achieved together during late spring and summer when chlorophyll a (chl a) concentrations were highest. This temporal coupling of macrofaunal and microalgal processes indicated that the activities of intertidal bivalves might depend largely on microphytobenthos seasonality. The isotopic signa- tures of the bivalve tissues demonstrated their dependence on organic matter of microphytobenthic source irrespective of season, despite a comparable contribution of phytoplankton to the diet of the suspension-feeding bivalve. These results highlight the importance of seasonal development of microphytobenthos as an available food source during the critical period of gamete production and growth for both suspension- and deposit-feeding bivalves.