The central hypothesis for the IML-CZO is that, through human modification, the critical zone of IMLs has passed a tipping point (or threshold) and has changed from being a transformer of material flux, with high nutrient, water, and sediment storage, to being a transporter. This change threatens the resilience of the landscape to accommodate future impacts associated with ongoing human activity, including climate change and bioenergy crop production. The vulnerability of the IMLs increases as these human activities intensify, compromising the sustainability of key critical-zone services on which ecological systems and human populations depend. Understanding and quantifying shifts in the response of the critical zone to human development remains a challenge, and current assessments are at best qualitative.
The IML-CZO will first examine how:
Researchers will next capture the connectivity of contemporary hydrological, geomorphological, and biogeochemical processes along different flow paths by quantifying the stores and residence times of water, SOM, DOC, and sediment.
24 Apr 2014 - Information for the 2014 All Hands Meeting for the CZO Network on 21-14 September, including registration information and abstract submission.
03 Mar 2014 - The IML-CZO focuses on intensely managed agricultural and urban landscapes in Iowa, Illinois, and Minnesota.
02 Jul 2014 - Recent flooding in southeastern Iowa has brought high water and wind damage to the Clear Creek watershed in the IML-CZO. Researcher Art Bettis took...
08 Apr 2014 - Reactive Transport Modeling Survey – Community Needs for Biogeochemical Studies The below survey is designed by Alexis Navarre-Sitchler, Kate...
02 Apr 2014 - March 31, 2014. Dr. Enriqueta Barrera (NSF CZO program director) and Dr. Gordon Grant (USFS; CZO Steering Committee chairperson)
01 Apr 2014 - Soil sampling is underway at the Clear Creek watershed.
Power law scaling of topographic depressions and their hydrologic connectivity. Phong, V. V. Le and Praveen Kumar, P. (2014): Geophysical Research Letters
Emergent and divergent resilience behavior in catastrophic shift systems. Srinivasan, V. and Kumar, P. (2014): Ecological Modelling
Simultaneous improvement in productivity, water use, and albedo through crop structural modification. Drewry, D.T., Kumar, P., and Long, S.P. (2014): Global Change Biology
Antecedent Moisture Controls on Stream Nitrate Flux in an Agricultural Watershed. Davis. C.A., Ward, A.S., Burgin, A.J., Loecke, T.D., Riveros-Iregui, D.A., Schnoebelen, D.J., Just, C.L., Thomas, S.A., Weber, L.J., St. Clair, M.A. (2014): Journal of Environmental Quality
A stability analysis of semi-cohesive streambanks with CONCEPTS: Couple field and laboratory investigations to quantify the onset of fluvial erosion and mass failure. Sutarto, T.E., Papanicolaou, A.N., Wilson, C.G., and Langendoen, E. (2014): Journal of Hydraulic Engineering-ASCE
Passive regulation of soil biogeochemical cycling by root water transport. Quijano, J. C., P. Kumar, and D. Drewry (2013): Water Resources Research 49(6): 3729–3746,
Wepp: Model use, calibration, validation. Flanagan, D.C., Frankenberger, J.R., and Ascough, J.C. (2012): Transactions of the American Society of Agricultural and Biological Engineering
Quantifying and partitioning fine sediment loads in an intensively agricultural headwater system. Wilson, C.G., Papanicolaou, A.N., and Denn, K.D. (2012): Journal of Soil and Sediments
Climatic and biotic controls on silt production and accumulation of loess. Bettis, E.A. (2012): Nature Education Knowledge
Competitive and mutualistic dependencies in multispecies vegetation dynamics enabled by hydraulic redistribution. Quijano, J. C., P. Kumar, and D. Drewry, A. Goldstein, and L. Misson (2012): Water Resources Research 48(5): 1-22