Quantifying kelp detrital pathways: what is potentially locked away as Blue Carbon?

海带森林具有全球最高的植物生产率，每单位面积460 g C m2/年至3000 g C m2/年[1]，对我们沿海系统的生物多样性非常重要。据估计，海带系统产生的80%的生物量主要作为碎屑材料输出到浅水和深水系统[2]。然而，人们对碎屑路径的动力学知之甚少[3]，特别是物质分解成减小的粒度级的速率，以及这对颗粒运输和原位再矿化速率的影响。这一信息在确定碎屑碳的比例时具有重要意义，这些碎屑碳将被矿化，释放到沿海沃茨中的CO2，以及哪些可能被输出到沉积物中以被锁定为蓝碳。这个跨学科博士学位的目的是确定海带生物量分解率在不同的环境条件下，如流体力学（波与流速），温度和光使用实验室和现场实验方法。此外，海带衰老和脱落的生物地球化学动力学将通过实地采样来阐明，以确定这些过程如何影响溶解有机碳的产生和组成，以及颗粒有机碳库如何被沿海和陆架海的无脊椎动物进一步分解。博士候选人将在Portaferry的女王海洋实验室（QML）工作，北方爱尔兰，QML的设施包括室内和室外水族馆设施，海水流动，并且靠近野外地点。候选人将与Louise Kregting博士（QUB）密切合作，他是一位具有生产力和生态生理学大型藻类与生物物理相互作用的专业知识的藻类学家，Jamie Dick教授（QUB）将提供生物分解过程的专业知识，例如，草食性和食草性甲壳类动物，这可以极大地促进转化为细颗粒有机物，Ursula Witte教授（UoA）。一位生物海洋学家，擅长实验方法，以阐明和追踪碳的早期成岩作用，这是了解海带衍生的有机物如何保存在海洋沉积物中的基础，另一位是William Hunter博士（AFBI，NI），他的专长是海洋生物地球化学，对环境变化如何影响碳和营养循环特别感兴趣。该研究将提供广泛领域的培训，包括管理碎屑途径的化学，物理和生物过程。全面的培训将给予学生，但是，在海洋生物学，定量生态学，数据分析和水化学与沿海流体动力学和生物物理相互作用的赞赏背景将是可取的。

Kelp forests have some of the highest plant production rates globally of between 460 g C m2 yr to 3000 g C m2 yr per unit area [1] and are important for the biodiversity of our coastal systems. It has been estimated that 80% of the biomass produced by kelp systems is exported to shallow- and deep-water systems primarily as detrital material [2]. Yet very little is known of the dynamics of the detrital pathway [3], in particular, the rate of breakdown of the material into decreasing size fractions and the effect of this on particle transport and remineralization rates in situ. This information is of significance when determining the proportion of the detrital carbon that will be remineralised, releasing CO2 into the coastal waters and what is potentially exported to the sediments to be locked away as blue-carbon. The aim of this interdisciplinary PhD is to determine the rate of kelp biomass breakdown under varying environmental conditions such as hydrodynamics (waves vs current velocity), temperature, and light using both laboratory and field experimental approaches. Additionally, the biogeochemical dynamics of kelp from senescence and shedding will be elucidated through field-based sampling to determine how these processes affect the production and composition of the dissolved organic carbon and particulate organic carbon pools are broken down further by invertebrates in coastal and shelf seas.The PhD candidate would be based at Queen's Marine Laboratory (QML) in Portaferry, Northern Ireland where QML's facilities are comprised of indoor and outdoor aquarium facilities with running seawater as well as being close to field locations. The candidate would work closely alongside Dr Louise Kregting (QUB), a phycologist with expertise in productivity and eco-physiology macroalgae merged with biophysical interactions, Prof Jamie Dick (QUB) who will provide expertise on biological breakdown processes by, for example, herbivorous and detritivorous crustaceans, which can contribute immensely to conversion of course to fine particulate organic matter, Prof Ursula Witte (UoA), a biological oceanographer with expertise on experimental methods to elucidate and trace the early diagenesis of carbon fundamental to understanding how kelp-derived organic matter is preserved in marine sediments and Dr William Hunter (AFBI, NI) who's expertise is in marine biogeochemistry, with a specific interest in how environmental changes affects carbon and nutrient cycling. The research would provide training in a wide range of areas including chemical, physical, and biological processes that govern the detrital pathway. Full training will be given to the student, however, a background in marine biology, quantitative ecology, data analysis, and water chemistry with an appreciation of coastal fluid dynamics and biophysical interactions will be desirable.