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Title: Advances in Biogeochemical Modeling for Intensively Managed Landscapes
The study of Critical Zone (CZ) biogeochemistry in Intensively Managed Landscapes is a study of transitions. Large-scale anthropogenic inputs in the form of agricultural practices have induced significant shifts in the transport and transformation of water, carbon, and nutrients across the landscape. Disentangling the present-day complexity of physical, biological, and hydrologic CZ processes in intensively managed landscapes requires us to first understand the interplay between underlying natural processes which have occurred over geologic time scales from the overpowering, comparatively abrupt onset of intensive agricultural practices that have dominated the landscape in recent centuries. Modeling provides a unique advantage to extricate such complex processes. Advancements in recent years have improved our ability to elucidate (1) the coevolution of soil organic carbon storage, movement, and decomposition under climate and land cover changes, (2) the impacts of intensive agricultural management practices on age-nutrient dynamics and their consequential modification of rates and landscape fluxes, and (3) the integral regulatory role of vegetation and root exudation on CZ biogeochemical processes. In this chapter, we will review several recent models developed in the Intensively Managed Landscape Critical Zone Observatory in Illinois, USA that advance our understanding of critical transitions in biogeochemical dynamics due to intensive management more » and discuss future challenges. « less
Wymore, A.S.; Yang, W.H.; Silver, W.L.; McDowell, W.H.; Chorover, J.
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Biogeochemistry of the Critical Zone
Sponsoring Org:
National Science Foundation
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