Assessing benthic recovery following cessation of salmon farming using eDNA metabarcoding (ABReDNA)

鲑鱼养殖在一定程度上丰富了当地沉积物中的有机物（OM），这取决于当地的水动力制度、场地特征和宿主鱼类生物量。OM积累/细菌同化驱动大型底栖动物的变化，这些变化被用作活性场址法规合规性评估的指标。大多数获得许可的地点仍在生产，目前关于停止养殖后沉积物恢复动态的信息很少。该学生将加入一个国际团队，开发eDNA方法来监测生态系统，特别关注水产养殖。该博士生将与CASE的合作者SEPA一起，为我们目前的知识做出重大贡献，主要集中在两个领域：1。元条形码数据变异性的来源，包括“实验室”效应和PCR效应。学生将进行方差分析，通过比较不同实验室制备的相同样品的PCR结果，将实验室效应（例如PCR）纳入背景。2. eDNA与大型底栖生物恢复的相似性。使用大型底栖生物验证的元条形码方法来跟踪养鱼场底栖生物的恢复，学生将评估细菌组合如何随着时间的推移而变化，并将这些变化映射到大型底栖生物的变化上，以评估两种方法之间的差异。

Salmon farming enriches local sediments with organic matter (OM) to an extent that depends on the local hydrodynamic regime, site characteristics and hosted fish biomass. The OM accumulation/bacterial assimilation drives changes in the macrobenthos and these changes are used as indicators in regulatory-compliance assessment for active farm sites. Most licensed sites are still in production and there is currently little information on the dynamics of sediment recovery following cessation of farming. The student will join an international team developing the eDNA approach to ecosystem monitoring, specifically focussed on aquaculture. This PhD student, with CASE collaborators SEPA, will make a substantial contribution to our current knowledge focussing on two main areas: 1. Sources of variability in metabarcoding data, including 'laboratory' and PCR effects. The student will conduct a variance analysis to put lab-effects (e.g. PCR) into context by comparing PCR results, from the same samples, as prepared in different laboratories. 2. Similarities between eDNA- and macrobenthic recovery. Using macrobenthic-validated metabarcoding approaches to track benthic recovery at a fish-farm site, the student will assess how bacterial assemblages change, over time, and will map these changes onto macrobenthic changes to assess differences between the two approaches.