Hidden Processes During Seasonal Isolation of a High-Altitude Watershed

摘要: Biogeochemical processes capable of altering global carbon systems occur frequently in Earth’s Critical Zone–the area spanning from vegetation canopy to saturated bedrock–yet many these phenomena are difficult detect. Observation is limited by the seasonal inaccessibility remote ecosystems, such as those mountainous, snow- and ice-dominated areas. This isolation leads a distinct gap biogeochemical knowledge that ultimately affects accuracy confidence with which ecosystems can be computationally modeled for purpose projecting change under different climate scenarios. To examine high-altitude, headwater ecosystem’s role methanogenesis, sulfate reduction, groundwater-surface water exchange, samples were continuously collected river hyporheic zones during winter East River (ER), CO watershed. Measurements ER surface revealed up 50 µM levels dissolved methane July through September, while 12 cm deep zone at same location showed spring early summer peak strong biogenic signature (< 65 µM, -60.76‰) before declining. Continuously 𝛿18O-H2O 𝛿2H-H2O isotopes column exhibited similar patterns previous discrete measurements, experienced fluctuations 𝛿18O-H2O, alluding significant groundwater interactions. microbial communities late fall diverse populations reflect taxonomic composition ecologically systems, including taxa indicative cycling this system. These measurements captured several components high-altitude watershed response seasonality, strengthening our understanding months.