S1 Title: Vegetation Loss Decreases Salt Marsh Denitrification Capacity: Implications for 1 Marsh Erosion 2 3 Authors: Sarra E. Hinshaw 1 2* , Corianne Tatariw 1 2* , Nikaela Flournoy 1 , Alice 4 Kleinhuizen 1 2 , Caitlin Taylor 1 , Patricia A. Sobecky 1 , Behzad Mortazavi 1 2* 5 6 Authors address: 1 University of Alabama, Department of Biological Sciences, 7 Tuscaloosa, AL 35487, 2 Dauphin Island Sea Lab, Dauphin Island, AL 36528 8 9 *S.E.H. and C.T. have contributed equally to this manuscript 10 **Corresponding Author 11 University of Alabama 12 Dauphin Island Sea Laboratory 13 101 Bienville Blvd 14 Dauphin Island, AL 36528 15 251-861-2141 16 bmortazavi@ua.edu 17 Keywords: Deepwater Horizon, isotope pairing, Chandeleur Islands, Spartina 18 alterniflora, napA, nirS, norB, nutrient flux 19 20 Pages: 11 21 Tables: 5 22 Figures: 4 23