Degree
Doctor of Philosophy (PhD)
Department
Department of Oceanography and Coastal Science
Document Type
Dissertation
Abstract
The land-ocean interface is extremely heterogeneous in terms of lateral input, marine primary productivity, air-sea fluxes, and sediment transport processes. Climate change and human perturbation has the potential to influence the carbon cycle along this continuum through anticipated changes in weathering, river discharge, vegetation, organic matter production as well as alteration of carbon transformation and transport processes. This dissertation focuses on how changes in river discharge, sea level rise, and increasing winter storms can impact carbon cycling along the land ocean continuum in coastal Louisiana. My research suggests (i) sea-level rise and associated saltwater intrusion has the potential to shift the microbial respiration structure of Louisiana marshes, leading to a decrease in iron reduction and increase in sulfate reduction which will have profound influence of plant communities, carbon respiration pathways and methane production from wetlands; (ii) temporary increase in river discharge can alter benthic carbon respiration pathways by enhancing sediment carbon remineralization on likely through additional supply of reactive Fe and Mn. and (iii) winter-storm driven fluid-mud events likely do not lead to long term increase in respiration of sediment carbon in shallow Louisiana shelf due to a combination of rapid respiration of labile organic carbon during summer months, presence of more resilient terrestrial carbon faction in these sediment and lower temperature during winter. However, our results are not conclusive as most of our sampling occurred about a month after storm events and likely missed any remineralization pulses immediately after these events. Overall, my research highlights the substantial changes that are likely to occur to carbon cycling in coastal Louisiana under future projected climate changes. These studies have provided a much-needed foundation for future research seeking to understand how the Louisiana coast carbon cycle will be affected by different climate change scenarios.
Date
3-25-2024
Recommended Citation
Clower, Patrick O., "CARBON CYCLING ACROSS LAND OCEAN CONTINUUM UNDER ACCELERATED CLIMATE CHANGES" (2024). LSU Doctoral Dissertations. 6378.
https://repository.lsu.edu/gradschool_dissertations/6378
Committee Chair
Maiti, Kanchan