Deep vadose (partially saturated) zones cover over 50% of the Earth’s land surface. This research focuses on various facets of hydrology, specifically in understanding water sustainability challenges in forested and agroforested landscapes. We use a multi-tracer approach, employing stable and radioactive isotopes to unravel the intricacies of groundwater recharge mechanisms in thick vadose zones. This research identifies the contributions of piston and preferential flows to groundwater recharge, while elucidating the role of land use change on recharge rates and water sustainability. It also provides a model-based prognosis of where and when the tritium tracing method may be valid globally. The insights here are crucial, especially in semi-arid environments, where understanding groundwater recharge can have significant implications for water resources management.
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Watershed (Eco)hydrologyImagine trees as not just plants but as engineers of the ground they grow in and the water they suck up. These green giants don't just absorb water from the soil; they're actively involved in shaping the very ground they root into. We are curious about understanding how trees interact with the soil and water underneath them. We look at different places with different types of trees and climates to see if the trees affect how water moves in the ground and even how soils form. We also try to figure out what types of water trees prefer—yes, trees can be picky about their water!
Understanding the role of trees in the critical zone
Publications: Brantley et al. (2017); Evaristo et al. (2017a); Zhang, Evaristo, et al. (2017); Evaristo et al. (2017b); Daly et al. (2017); Evaristo et al. (2017c); Knighton et al. (2020); Knighton et al. (2021) The 'two water worlds' hypothesis testing
Publications: Evaristo et al. (2015); Evaristo et al. (2016); Berry et al. (2017); Evaristo et al. (2019); Qiu et al. (2019); Evaristo et al. (2021) |
Advances in image-based modeling have enabled us to view water dynamics in the rhizosphere (plant root zone) in new ways. Combined with pore-scale modeling, this research seeks to understand how water moves around plant roots. Meanwhile, advances in clay mineral isotope paleothermometry challenge some of the preexisting assumptions in understanding the Earth's climate history. By incorporating factors such as soil water evaporation and temperature variability, new models suggest much more nuanced interpretation. Both fields underline the critical role of detailed, localized processes in understanding broader environmental and climatic phenomena.
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Water quality: from headwaters to coastal reefsThis research examines water systems across various environments, from rivers in semi-arid settings, to mangrove forests, volcanic coastlines, and urban streams. Using a multi-tracer approach, we find that natural processes such as weathering and human activities such as farming can significantly impact water quality. For instance, in Vietnam's mangrove forests, the interplay of plants and tides alters dissolved nutrients, while in coastal and urban areas, factors such as submarine groundwater discharge and rainfall-induced acidity can potentially affect the integrity of the ecosystems in and around them. This research is vital for understanding and preserving the quality of water in diverse settings, which is essential for both ecological health and human well-being.
Nitrate source(s) tracing
Publications: Li et. al (2019); Taillardat et al. (2019); Matiatos et al. (2023) Submarine groundwater discharge
Publication: Cardenas et al. (2020) Understanding flowpath influence on acidic streams
Publication: Ramchunder et al. (2022) |