Microtaphonomy of organic materials at sediment-water interface-Experimental Research for establishing paleoenvitonmental proxies in consideration to microbial processes-

在海面产生的有机物质沉积在海底，并在沉积物-水界面(SWI)被底栖生物消耗。本研究旨在通过现场实验和实验室实验，阐明小型底栖动物和小型底栖动物如何在SWI消耗有机物质。碳13标记的单细胞浮游植物(杜氏藻和角毛藻)和细菌供应在投喂装置的底泥表面。总共有八套仪器安装在海底。每隔一天恢复3个顶端，直到6天后。在实验室显微镜下采集了小型底栖动物，包括有孔虫和后生动物。用气相色谱-质谱仪测定了各物种的δ^&lt；13&gt；C值。底栖有孔虫能快速消化新鲜食材。80%到90%的消化食品原料通过呼吸作用矿化成二氧化碳气体。它们中的其余部分可能被同化成有孔虫细胞物质。不同物种对食物原料的反应不同，特别是对每种取食行为的反应不同。与沉淀物给料器相比，植物碎屑给料器的响应速度最快。在这项研究中，在有孔虫物种中没有特定的细菌群可以分析。在相模湾中心也进行了现场测量，使用在着陆器系统中组装的传感器微电极和平面光电系统。在SWI形成了几毫米到1厘米厚的氧化层。在SWI上观察到2厘米尺度的溶氧斑块。这可能与底栖有孔虫的三维分布模式很好地对应。在这项研究中，我们开发了一种高灵敏度的光电膜。通过本研究，我们可以得出结论：有孔虫是珊瑚礁有机物质的主要消耗者。

Organic materials produced at sea surface are deposited on sea floor and are consumed by benthic organisms at Sediment-water Interface(SWI). This research aims to elucidate how micro-and meio-benthos consume organic materials at SWI through in situ and laboratory experiments.In situ experiments were conducted at the central part of Sagami Bay. Carbon 13 labeled single-celled phytoplankton (Dunaliella and Chaetoceros) and bacteria were supplied on sediment surface of feeding apparatus. In total, eight-set of apparatuses were situated on the sea floor. Three apperatuses were recovered every two days until 6 days have passed. Meiobenthos, both foraminifera and metazoan meiobenthos were picked under microscope in the laboratory. δ ^<13>C values of each species were measured with GC-mass spectrometer. Benthic foraminifera digested fresh food materials rapidly. Eighty to Ninety percentages of digested food materials are calculated to mineralize into carbon dioxide gas through respiration. Rests of them may assimilate into foraminiferal cell materials. Responses in food materials are different from species to species, in particular to each feeding behavior. Phytodetrital feeder should be most quick responder in comparison to deposit feeder. There are no specific bacteriovore among foraminiferal species that could analyze during this study.In situ measurements have also conducted at Sagami Bay center using both sensor microelectrode and planer optode systems that have assembled in lander system. A few millimeter to 1 cm thick oxygenated layer is developed at SWI. Two cm scale patchness of dissolved oxygen was observed at SWI. This may correspond well to 3D-distributional patterns of benthic foraminifera. We developed a highly sensitive optode film during this research. It can detect behaviors of benthic foraminifera at SWI.Through this research, we can conclude that foraminifera act a big role as primary consumer of organic materials at SWI.