Benthic mineralization and microscale heterogeneity

• Main Author: Larsen, Morten
• Other Authors: Glud, Ronnie
• Published: University of the Highlands and Islands 2012
• Online Access: http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.739365

Traditionally, marine sediments are viewed as horizontally layered structures. However, in recent decades there has been growing awareness of the naturally occurring microscale heterogeneity affecting the biogeochemical functioning. Studies on microscale dynamics have been facilitated by recent developments of high resolution sensors for 2-dimensional chemical imaging. The presented work has contributed to this development by introducing a simple, robust and inexpensive 2-dimensional imaging system, which has made the approach accessible to a much wider user-group. The presented study utilizes the advances in chemical imaging to study benthic processes in systems, where the natural function of microscale heterogeneity has been ignored or improperly appreciated. The results confirm the importance of natural heterogeneity in benthic ecosystem functioning including: trace metal mobilization, microbial abundance/activity and localized increased concentrations of electron donors. The combined findings highlight the need for high spatial resolution to achieve a full conceptual and quantitative understanding of benthic microbial systems. The current work has opened a number of avenues for future work on microscale patchiness. This especially includes; I) Plant and microorganism effects on rhizosphere biogeochemistry; II) Microscale heterogeneity of microbial abundance, diversity and function; III) Fauna induced microscale heterogeneity and structure.