EGU Abstracts Due: January 10th, 2019
EGU Session HS2.4.3 Understanding hydrologic and biogeochemical responses to climate and human-induced perturbations in the Anthropocene
Conveners: Pamela L. Sullivan, Li Li, and Paolo Benettin
Session Abstract: Soil fabric, the distribution of pores and their connected nature, controls the flow paths and transit time distribution of water and, thus, the propensity to weather minerals, degrade contaminants and transform nutrients across the critical zone (CZ; Earth’s living skin that stretches from the canopy to depths of circulating groundwater). Evidence is emerging from natural and applied sciences that demonstrates soil fabric is responding on short timescales (e.g., months and decades) to climate and land cover change. These processes are linked to biotic factors such as alteration to microbial decay of organic matter that governs the trajectory of aggregate stability and root growth that can either clog pores or enhance macroporosity. In addition, shifts in abiotic drivers such as freeze-thaw and wet-dry cycles also alter stress fields in the soil and trajectory of its fabric. Process-based and data-based models have started to unearth how these rapid changes in soil fabric may alter water and nutrient fluxes across terrestrial Earth. To better understand the timescale over which changes in soil fabric occur, if that rate is responding to the “great acceleration” of the Anthropocene, and the cascading effects on hydrologic and biogeochemical dynamics of the CZ (present and future), we invite abstracts that: 1) examine these processes in lab, field, and modeling experiments, across large spatial (aggregate to continental) and temporal (seconds to centuries) scales, 2) use new technologies and methods to quantify soil structure and its relationship to biogeo-chemical and -physical processes of the CZ and 3) develop quantitative metrics that can advance process-based representation and hypothesis testing.