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Abstract Observatory‐scale data collection efforts allow unprecedented opportunities for integrative, multidisciplinary investigations in large, complex watersheds, which can affect management decisions and policy. Through the National Science Foundation‐funded REACH (REsilience under Accelerated CHange) project, in collaboration with the Intensively Managed Landscapes‐Critical Zone Observatory, we have collected a series of multidisciplinary data sets throughout the Minnesota River Basin in south‐central Minnesota, USA, a 43,400‐km2tributary to the Upper Mississippi River. Postglacial incision within the Minnesota River valley created an erosional landscape highly responsive to hydrologic change, allowing for transdisciplinary research into the complex cascade of environmental changes that occur due to hydrology and land use alterations from intensive agricultural management and climate change. Data sets collected include water chemistry and biogeochemical data, geochemical fingerprinting of major sediment sources, high‐resolution monitoring of river bluff erosion, and repeat channel cross‐sectional and bathymetry data following major floods. The data collection efforts led to development of a series of integrative reduced complexity models that provide deeper insight into how water, sediment, and nutrients route and transform through a large channel network and respond to change. These models represent the culmination of efforts to integrate interdisciplinary data sets and science to gain new insights into watershed‐scale processes in order to advance management and decision making. The purpose of this paper is to present a synthesis of the data sets and models, disseminate them to the community for further research, and identify mechanisms used to expand the temporal and spatial extent of short‐term observatory‐scale data collection efforts.
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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 and discuss future challenges.
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- Award ID(s):
- 2012850
- PAR ID:
- 10333652
- Editor(s):
- Wymore, A.S.; Yang, W.H.; Silver, W.L.; McDowell, W.H.; Chorover, J.
- Date Published:
- Journal Name:
- Biogeochemistry of the Critical Zone
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Conference Paper:
- https://doi.org/10.1007/978-3-030-95921-0_6
