Rudnick D T, Elmgren R, Frithsen J B
Marine Ecosystems Research Laboratory, Graduate School of Oceanography, University of Rhode Island, 02882, Narragansett, RI, USA.
Oecologia. 1985 Sep;67(2):157-168. doi: 10.1007/BF00384279.
The muds of a shallow (7 m) site in Narragansett Bay, Rhode Island contained higher abundances of meiofauna (averaging 17×10 individuals per m and ash free dry weight of 2.9 g/m during a 3 year period) than have been found in any other sediment. The majority of sublittoral muds, worldwide, have been reported to contain about 10 individuals per m. This difference is attributed primarily to differences in sampling techniques and laboratory processing.Extremely high meiofaunal abundances may have also occurred because Narragansett Bay sediments were a foodrich environment. While the quantity of organic deposition in the bay is not unusually high for coastal waters, this input, primarily composed of diatom detritus, may contain an unusually high proportion of labile organics. Furthermore, meiofauna could have thrived because of spatial segregation of meiofauna and macrofauna. While meiofauna were concentrated at the sediment-water interface, most macrofauna were subsurface deposit feeders. Macrofaunal competition with, and ingestion of meiofauna may thus have been minimized.The seasonal cycles of meiofauna and macrofauna were similar. Highest abundances and biomass were observed in May and June and lowest values in the late summer and fall. Springtime increases of meiofaunal abundance were observed in all depth horizons, to 10 cm. We hypothesize that phytoplankton detritus accumulated in the sediment during the winter and early spring, and that the benthos responded to this store of food when temperatures rose rapidly in the late spring. By late summer, the stored detritus was exhausted and the benthos declined.
罗德岛纳拉甘西特湾一个浅水区（7米深）的淤泥中，小型底栖动物的丰度更高（在3年期间平均每立方米有17×10个个体，无灰干重为2.9克/立方米），比在其他任何沉积物中发现的都要高。据报道，全球大多数潮下带淤泥每立方米约含10个个体。这种差异主要归因于采样技术和实验室处理的不同。纳拉甘西特湾淤泥中极高的小型底栖动物丰度也可能是因为其沉积物是食物丰富的环境。虽然该海湾的有机沉积物数量对于沿海水域来说并非异常高，但这种输入主要由硅藻碎屑组成，可能含有异常高比例的易分解有机物。此外，小型底栖动物能够繁盛可能是因为小型底栖动物和大型底栖动物在空间上的分隔。小型底栖动物集中在沉积物 - 水界面，而大多数大型底栖动物是地下沉积物摄食者。因此，大型底栖动物与小型底栖动物的竞争以及对小型底栖动物的摄食可能已降至最低。小型底栖动物和大型底栖动物的季节循环相似。在五月和六月观察到丰度和生物量最高，而在夏末和秋季则最低。在所有深度至10厘米的层面都观察到小型底栖动物丰度在春季增加。我们推测，浮游植物碎屑在冬季和早春积累在沉积物中，当春季后期温度迅速上升时，底栖生物对这种食物储备做出了反应。到夏末，储存的碎屑耗尽，底栖生物数量下降。
