We seek to address two questions:
1.  How important is hyporheic regeneration relative to other important ecosystem or landscape fluxes (e.g. hyporheic mineralization, throughflow, lateral flow)?
2. How does the interaction among these processes differ over the extreme arctic season?

During the “shoulder seasons” in the arctic (spring and fall) the extent of sub-stream thaw basin controls the extent of the hyporheic zone, while during the summer the thaw basin is generally deeper than the hyporheic zone. This creates a situation – unique to the arctic – in which the hyporheic zone and its influences on stream biogeochemical processes change seasonally from being non-existent in the early spring and late fall to being fully formed and functional in the summer. Simultaneously, important terrestrial ecosystem characteristics and processes that affect stream function also vary seasonally (e.g., snowmelt, vegetation influences, DOM quantity and quality, microbial activity).

We propose to quantify the relative influences of throughflow, lateral inputs, and hyporheic regeneration on the seasonal fluxes C, N, and P in an arctic river network, and determine how these influences will shift under seasonal conditions that are likely to be substantially different in the future.

Tundra stream in Northern Alaska.