Dr. Mark Johnson is working to understand how land use practices influence interactions between hydrological and ecological processes, and how these ecohydrological processes further affect ecosystem services including carbon sequestration. Unraveling interactions between the water cycle and the carbon cycle is essential for improving the sustainability of land and water management, especially under changing climatic conditions. Dr. Johnson’s research in ecohydrology demonstrates that soil carbon processes are also integrally important to the health of freshwater ecosystems and drinking water supplies. Dr. Johnson and his team are testing carbon and water cycle interactions to address questions such as: How much carbon does water transport from the land into freshwater systems? His research can also help to answer very applied questions related to soil fertility and water use such as: How much food can be produced in urban environments, and how much water would that require? To address these and other related questions, Johnson is developing innovative approaches to ecohydrological research in partnership with communities, natural resource management agencies and organizations, and industry.
Google Scholar: https://scholar.google.ca/citations?user=KfQwll4AAAAJ&hl=en
Johnson, M.S., E.G. Couto, I. Messias, R. Amorim; J. Milesi, O.B. Pinto Jr, M. Biudes (2013). Soil CO2 dynamics in a tree island soil of the Pantanal: the role of soil water potential. PLOS ONE (in press). doi:10.1371/journal.pone.0064874
Dinsmore, K.J., M.B. Wallin, M.S. Johnson, M.F. Billett, K. Bishop, J. Pumpanen and A. Ojala (2013). Contrasting CO2 concentration discharge dynamics in headwater streams: a multi-catchment comparison. Journal of Geophysical Research: Biogeosciences (in press). doi:10.1002/jgrg.20047
Recha, J.W., J. Lehmann, M.T. Walter, A. Pell, L. Verchot, M.S. Johnson (2013). Stream water nutrient and organic carbon exports from tropical headwater catchments at a soil degradation gradient. Nutrient Cycling in Agroecosystems (in press). doi:10.1007/s10705-013-9554-0
I. Messias, E.G. Couto, O.B. Pinto Jr, Johnson, M.S. (2013). Monitoramento contínuo do potencial redox e de variáveis complementares em ambiente hipersazonal no Pantanal Norte (Monitoring soil redox potential and its interactions with associated variables in the northern Pantanal). Revista Brasileira de Ciência do Solo (Brazilian Journal of Soil Science) (in press).
Lathuilliere, M.J., M.S. Johnson and S.D. Donner (2012). Water use by terrestrial ecosystems: temporal variability in rainforest and agricultural contributions to evapotranspiration in Mato Grosso, Brazil. Environmental Research Letters 7:024024. doi:10.1088/1748-9326/7/2/024024
Jollymore, A., M.S. Johnson and I. Hawthorne (2012). Submersible UV-Vis spectroscopy for quantifying streamwater organic carbon dynamics: implementation and challenges before and after forest harvest in a headwater stream. Sensors 12(4):3798-3813. doi:10.3390/s120403798 (Special issue: Underwater Sensor Nodes and Networks)
Harma, K.J., M.S. Johnson, and S.J. Cohen (2012). Future water supply and demand in the Okanagan Basin, British Columbia: a scenario-based analysis of multiple, interacting stressors. Water Resources Management 26:667-689. doi:10.1007/s11269-011-9938-3
Novães Filho, J.P., E.G. Couto, L.C. Mattos Rodrigues, L.A. Chig, M.S. Johnson (2012). Indicativos de descontinuidade litológica em perfis de solos de uma microbacia sob floresta amazônica (Indicators of lithological discontinuity in soil profiles of a forested catchment). Revista Brasileira de Ciência do Solo (Brazilian Journal of Soil Science) 36:317-324. doi:10.1590/S0100-06832012000200001
Molodovskaya, M., O. Singurindy, B.K. Richards, J. Warland, M.S. Johnson, T. S. Steenhuis (2012). Temporal variability of nitrous oxide from fertilized croplands: hot moment analysis. Soil Science Society of America Journal 76:1728-1740. doi:10.2136/sssaj2012.0039
Recha, J.W., J. Lehmann, M.T. Walter, A. Pell, L. Verchot, M.S. Johnson (2012). Stream discharge in tropical headwater catchments as a result of forest clearing and soil degradation. Earth Interactions 16, paper 13:1-18. doi:10.1175/2012EI000439.1