Soil Lysimeter Excavation for Coupled Hydrological, Geochemical, and Microbiological Investigations.
Studying co-evolution of hydrological and biogeochemical processes in the subsurface of natural landscapes can enhance the understanding of coupled Earth-system processes. Such knowledge is imperative in improving predictions of hydro-biogeochemical cycles, especially under climate change scenarios. We present an experimental method, designed to capture sub-surface heterogeneity of an initially homogeneous soil system. This method is based on destructive sampling of a soil lysimeter designed to simulate a small-scale hillslope. A weighing lysimeter of one cubic meter capacity was divided into sections (voxels) and was excavated layer-by-layer, with sub samples being collected from each voxel. The excavation procedure was aimed at detecting the incipient heterogeneity of the system by focusing on the spatial assessment of hydrological, geochemical, and microbiological properties of the soil. Representative results of a few physicochemical variables tested show the development of heterogeneity. Additional work to test interactions between hydrological, geochemical, and microbiological signatures is planned to interpret the observed patterns. Our study also demonstrates the possibility of carrying out similar excavations in order to observe and quantify different aspects of soil-development under varying environmental conditions and scale.
Biosphere 2, University of Arizona; asengupta@email.arizona.edu.
Aditi
A
Sengupta
Department of Soil, Water and Environmental Science, University of Arizona.
Yadi
Y
Wang
Department of Hydrology and Water Resources, University of Arizona.
Antonio A
AA
Meira Neto
Department of Hydrology and Water Resources, University of Arizona.
Katarena A
KA
Matos
Biosphere 2, University of Arizona; Department of Soil, Water and Environmental Science, University of Arizona.
Katerina
K
Dontsova
Department of Soil, Water and Environmental Science, University of Arizona.
Rob
R
Root
Department of Soil, Water and Environmental Science, University of Arizona.
Julie W
JW
Neilson
Department of Soil, Water and Environmental Science, University of Arizona.
Raina M
RM
Maier
Biosphere 2, University of Arizona; Department of Soil, Water and Environmental Science, University of Arizona.
Jon
J
Chorover
Biosphere 2, University of Arizona; Department of Hydrology and Water Resources, University of Arizona.
Peter A
PA
Troch
D057231:Climate Change; D062070:Hydrology / Q000379:methods*; D012987:Soil / Q000737:chemistry*; D012988:Soil Microbiology; D012989:Soil Pollutants / Q000737:chemistry
D012987:Soil; D012989:Soil Pollutants