The spatial and temporal controls on variability of the relative contributions of groundwater within and between flow systems to shallow lakes in the low-relief glaciated Boreal Plains of Canada were evaluated. Eleven lakes located in a coarse glacial outwash, of varying topographic positions and potential groundwater contributing areas, were sampled annually for stable O and H isotope ratios over the course of 8 years. It was...

Tidal fresh marshes are at least as productive as nearby salt marshes, but much less is known about controls on primary production in tidal fresh vs. salt marshes. We studied a tidal fresh marsh in Georgia, U.S.A., dominated by the C 3 grass Zizaniopsis miliacea . We documented seasonal variation in Z. miliacea above‐ground biomass and below‐ground macro‐organic matter over 1 yr, and annual variation in end‐of‐season abovegrou...

We compared processing and fate of dissolved NO 3 − in two New England salt marsh ecosystems, one receiving natural flood tide concentrations of ∼1–4 μmol NO 3 − /L and the other receiving experimentally fertilized flood tides containing ∼70–100 μmol NO 3 − /L. We conducted simultaneous 15 NO 3 − (isotope) tracer additions from 23 to 28 July 2005 in the reference (8.4 ha) and fertilized (12.4 ha) systems to compare N dynamics...