Twilight zone to deep-ocean floor. Developing an understanding of particle dynamics and trophic interactions using a molecular experimental approach

光合初级生产是海洋食物链的基础。浮游植物固定的能量被转移到食草动物和更高的消费者。生产者和消费者之间的能量转移效率反映了生态系统的状态，例如养分充足与养分缺乏。通过下沉，表层沃茨的颗粒有机物被转移到深海，在那里，颗粒有机物是深海动物的重要资源，无论这些动物生活在中上层（水中）还是底栖（海底）环境中。我们知道，在中高纬度的北方大西洋，POM的沉积是由表层水春季水华季节性驱动的。然而，POM的组成存在相当大的变化，这部分是由浮游植物的性质驱动的，但也是由以它们为食的生物体驱动的。离开表面沃茨的POM大部分在所谓的黄昏区丢失;那里发生的过程也可能改变下沉POM的化学成分。我们对发生在阴阳魔界的POM的生物过程几乎一无所知。到达海底的海底动物所需的物质可能会发生很大变化，许多化学品可能会耗尽，然而，深海生物群落是高度多样化的。在这个项目中，我们将与国家海洋学中心、南安普顿和布里斯托大学的科学家合作，试图阐明固定在表面沃茨中的有机物中锁定的能量是如何在生活在深海的消费者之间分配的。我们将详细研究颗粒物质的化学，其中包括浮游植物和以其为食的小型生物（细菌和微型浮游动物），浮游动物和生活在深海和海底的大型动物的生物化学。我们还将使用遥控潜水器Isis进行孵化实验，以评估微生物如何分解阴阳魔界的有机物，以及生活在海底的大型动物如何以及是否能够对POM的流入作出反应。

Photosynthetic primary production is the basis of much of the oceanic food chain. The energy fixed by phytoplankton is transferred to grazers and to higher consumers. The efficiency of the energy transfer between producer and consumer reflects the state of the ecosystem, for example nutrient replete vs nutrient deficient. Through sinking, particulate organic matter (POM) from surface waters is transferred to the deep sea, where it is an important resource for deep-dwelling animals, be they living in pelagic (in the water) or benthic (at the sea floor) environments. We know that in the northern Atlantic Ocean at mid- to high latitude, the deposition of POM is seasonally driven by the surface water spring bloom. However, there is considerable variability in the composition of the POM, which is driven partly by the nature of the phytoplankton, but also by the organisms that graze on them. Much of the POM leaving surface waters is lost in the so-called twilight zone; processes occurring there also presumably modify the chemical composition of the sinking POM. We know virtually nothing about the biological processing of POM that occurs in the twilight zone. The material arriving at the sea floor which feeds the benthic animals is potentially highly altered and depleted in many chemicals, nevertheless, the deep-sea community is highly diverse. In this project, we will work with scientists at the National Oceanography Centre, Southampton and the University of Bristol to try to shed some light on how the energy locked up in organic matter fixed in surface waters is partitioned between consumers living in the deep sea. We will study in detail, the chemistry of particulate material, which includes the phytoplankton and small size organisms that feed on it (bacteria and microzooplankton), the biochemistry of the zooplankton and larger animals living in the deep sea and at the sea floor. We will also carry out incubation experiments using the remotely operated vehicle, Isis, in order to assess how micro-organisms break down organic matter in the twilight zone and how and whether large animals living at the sea floor are able to react to an influx of POM.