SGER: Development of in Situ Techniques for Quantifying Rates of Feeding, House Production and House Flux by Appendicularians

在海洋食物网中，水中附属物对颗粒动力学的贡献仍未得到充分研究。该项目将开发基于原位潜水的技术，从而更详细、更长期地调查具有较大房屋(直径1-30厘米)的物种的生态作用。这些物种鲜为人知，但在全球范围内的水柱环境中随处可见，数量往往很多，是现场记录摄食率、家养产量和家养通量的容易处理的目标。关于这些杂食性、非选择性滤食性喂食器的现场信息量有限，但令人信服，这表明它们可能在整个水柱中的物质流动中发挥核心作用，特别是在颗粒丰富的层中。首先，附肢动物能够快速繁殖后代。其次，大多数物种能够对广泛的颗粒物，包括微生物浮游植物、细菌和碎屑，有很高的捕食率。从充满颗粒的附属物房屋中出口或回收生物碳的速度取决于几个因素。例如，研究人员认为，表层和底栖生物区房屋上的颗粒负荷将分别与地表生产和再悬浮有关。颗粒选择、饲喂、家粪颗粒生产和家粪颗粒下沉的比率也将随着物种、颗粒选择和房屋年限的不同而不同。因此，开发可靠的现场方法对于更好地了解行为和环境参数如何相互作用影响颗粒物的命运至关重要。

The contribution of midwater appendicularians to particle dynamics remains understudied in marine food webs. This project will develop in situ submersible-based techniques that will lead to more detailed, long-term investigations of the ecological role of species with relatively large houses (1-30 cm diameter). These species are poorly known but ubiquitous in water column environments on a global scale, are often numerous, and are tractable targets for in situ documentation of rates of feeding, house production, and house flux. The limited but compelling amount of field information about these omnivorous, non-selective filter feeders suggests that they may have a central role in the flux of material throughout the water column, especially in particle-rich layers. First, appendicularians are capable of rapid generation times. Second, most species are capable of high grazing rates on a wide spectrum of particles, including microbial phytoplankton, bacteria, and detritus. The rate of export or recycling of biogenic carbon from particle-laden appendicularian houses depends upon several factors. For example, the investigator believes that particle loading on houses in the epipelagic and epibenthic zones will vary in relation to surface production and resuspension, respectively. Rates (of particle selection, feeding, house-fecal pellet production, and house-fecal pellet sinking) will also vary with species, particle selection, and house age. Therefore, developing reliable field methods will be essential to better understand how behavioral and environmental parameters interact to influence the fate of particulate matter.