​​​​​​​​​​​​​​​Current Research

The unifying theme of this body of work is to understand the fundamental dynamics of ecosystems and the influence of natural and anthropogenic perturbations/feedbacks on ecosystem functions.

                       

                       Ecosystem dynamics along  terrestrial-aquatic interfaces 

                                        The primary objective of this project is to examine how coupled plant-soil-water-microbe

                                        interactions, and related biogeochemical transformations and fluxes, respond to variable water

                                        availability and exposure to salt along coastal terrestrial aquatic interfaces. We are currently

                                        studying the underlying mechanisms driving carbon transformations and the magnitude of

                                        these exchanges to and from the atmosphere, soils, porewater, trees, and surface waters across

                                        the headwater-to-estuary continuum of Pacific Northwest, USA coastal watersheds. A

                                        combination of in situ measurements, high-resolution monitoring, and lab incubations are

                                        being used for development of a reactive transport model adapted for tidal systems. These

                                        models help to evaluate parameterization of the Energy Exascale Earth Systems Model

                                        (E3SM).Funding provided by Pacific Northwest National Laboratory, Lab Directed

                                        Research and Development. Lead PI: Nick Ward


                       Mechanistic understanding of tree methane emissions

                                         Among the largest uncertainties in the global CH4 budget is the role of forest trees. While     

                                         upland forest soils are typically a sink of atmospheric CH4, the emission of CH4 from tree

                                         stems to the atmosphere may balance, or even exceed this sink. This project uses molecular

                                         level tools to understand the microbial mechanisms driving methanogenesis and methane

                                         oxidation inside trees. A crowd-sourcing approach is being used to gather tree core samples

                                         from researchers around the world studying tree methane fluxes to develop understanding

                                         across numerous types of environments and climatic conditions. Funding is provided

                                         by Pacific Northwest National Laboratory, Lab Directed Research and Development.
                                        
Lead PI: Nick Ward


                       Metabolic response of eelgrass to environmental stress

                                        Seagrass is a critical habitat for a variety of ecosystem services such as fisheries, pollutant  
                                        detoxification, and sequestration of “blue” carbon. Significant effort has been made to restore  
                                        eelgrass, a keystone species in Puget Sound, but the success rate of restoration is limited by a
                                        lack of fundamental knowledge of how eelgrass responds/adapts to changing ocean      
                                        conditions. We are developing a suite of biomarker proxies for eelgrass health based on  
                                        cellular metabolite abundance. Funding provided by Pacific Northwest National Laboratory  
                                        Energy and Environment Lab Directed Research and Development (PNNL-EED-LDRD).
                                        Lead PI: Nick Ward


                       The role of priming effects on the conversion of blue

                       carbon to CO2 in the coastal zone 

                                         Blue carbon storage in coastal marshes is thought to be an essential mechanism for

                                         atmospheric CO2 sequestration, however, the release and subsequent breakdown of stored  

                                         blue carbon due to sea level rise is a potentially significant positive feedback for climate  

                                         change. This study utilizes a combination of innovative incubation approaches and cutting

                                         edge organic geochemical (e.g. FT-ICR-MS, LTQ Orbitrap MS, NMR, and GC-MS) and

                                         molecular biological analyses (e.g. metatranscriptomics) to answer fundamental questions

                                         concerning the mechanisms driving global biogeochemical cycles. Funding provided by the  

                                        Department of Energy Joint Genome Institute. Lead PI: Thomas Bianchi

                               Net eco
system exchange of the lower Amazon River

                                         This project seeks to unravel the sequence of processes and sources of

                                         terrestrially-derived organic matter that culminate in the immense CO2 outgassing to

                                         the atmosphere from tropical rivers worldwide. Funding provided by the Fundação de

                                         Amparo à Pesquisa do Estado de São Paulo (FAPESP) and the National Science

                                         Foundation (NSF). Lead PI: Jeff Richey 

                                         Website: http://boto.ocean.washington.edu/story/show/10


                       The influence of microbial priming effects on the carbon

                       balance of large river reservoirs

                             River impoundments significantly alter both the flow of water and biogeochemical cycled. This

                                        project evaluates the mechanisms of organic carbon decomposition in a large river reservoir,    

                                        the Columbia River. We hypothesize that microbail priming effects play an important role in

                                        carbon transformations in reservoirs due to an abundance of algal material linked to sediment

                                        settling and inputs of terrestrially-derived carbon from surrounding tributaries. We use a

                                        combination of field measurements and incubation experiments to evaluate these

                                        mechanisms. Funding is provided bythe US. Department of Energy, Subsurface

                                        Biogeochemical Research program. Lead PI: Tom Bianchi  



                                         

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Ecosystems Research

Nick Ward, PhD