Evaristo Critical Zone Hydrology Lab

Jaivime is an Assistant Professor at the Warnell School of Forestry and Natural Resources, University of Georgia. A full-blooded Filipino geoscientist with a non-traditional career path, he earned an undergraduate degree in Cell Biology from the University of the Philippines before spending a decade in industry and management consulting. He later pursued an MS in Geosciences (hydrogeology concentration) at the University of Pennsylvania, followed by a PhD at the Global Institute for Water Security, University of Saskatchewan. From 2019 to 2024, he was a tenured Assistant Professor at Utrecht University.

His research focuses on the critical zone and uses tools in hydrology, water resources, and isotope geochemistry to characterize the influence of natural and anthropogenic processes on matter and energy exchange across the hydrosphere, geosphere, and atmosphere.

Outside of work, he loves spending time with his wife and two kids!

Current Graduate Students

PhD Student (expected 2029)

Maria Jessica Gabriel, M.S.

Jessica is a PhD student at Warnell and an assistant professor at the University of the Philippines Los Baños. She finished an Erasmus Mundus Joint Masters Program in Sustainable Tropical Forestry (SUTROFOR) at Bangor University, UK and the University of Copenhagen, Denmark. She is particularly interested in understanding the relationships between rooting depths and forest disturbance from hurricanes and droughts.

Funding: U.S. Forest Service

MS Student (expected 2027)

Audra Werley

Audra is a recent graduate of the College of Coastal Georgia with a BS in Environmental Science. She has experience as an environmental consultant and is passionate about wetland conservation and management. She is interested in surface and groundwater interaction using environmental tracers and numerical modeling.

Funding: The Chemours Company; U.S. Geological Survey

Current Undergraduate Students

Summer 2026 Hydrology & Water Resources Intern

Maxton Moreland

Maxton joins the lab as Summer 2026 Hydrology and Water Resources Intern. He is interested in understanding how natural disasters impact the stability of forest and coastal ecosystems. Maxton is a prospective 2028 graduate of Warnell for a degree in Natural Resource Management and Sustainability with a concentration in Water and Soil Resources.

Research

Exploring the critical zone through isotope geochemistry and hydrology

Vadose Zone Processes & Land Use

Deep vadose (partially saturated) zones cover over 50% of the Earth's land surface. This research uses a multi-tracer approach, employing stable and radioactive isotopes to unravel groundwater recharge mechanisms in thick vadose zones — identifying the contributions of piston and preferential flows while elucidating the role of land use change on recharge rates and water sustainability.

Key publications: Huang, Evaristo, Li (2019); Xiang, Evaristo, Li (2020); Zhao et al. (2021); Shi et al. (2021); Tao, Evaristo, et al. (2023); Zhao et al. (2024); Huang, Evaristo, et al. (2024, Vadose Zone J.)

Watershed Ecohydrology

Trees are not just plants but engineers of the ground they grow in and the water they take up. We examine how trees interact with soil and water across different climates and forest types — and even what kinds of water trees prefer. Yes, trees can be picky about their water!

Two water worlds: Evaristo et al. (2015, Nature); Evaristo et al. (2016); Berry et al. (2017); Evaristo et al. (2019, WRR); Evaristo et al. (2021, PNAS)
Trees in the critical zone: Brantley et al. (2017); Evaristo & McDonnell (2017, Sci. Rep.); Knighton et al. (2020, 2021, GRL)

Rhizosphere & Pore-Scale Processes

Advances in image-based modeling have enabled new views of water dynamics around plant roots. Meanwhile, advances in clay mineral isotope paleothermometry challenge preexisting assumptions about Earth's climate history by incorporating soil water evaporation and temperature variability.

Paleothermometry: Ibarra & Evaristo (2024, Commun. Earth Environ.)
Rhizosphere: Daly et al. (2017)

Water Quality: Headwaters to Coastal Reefs

This research examines water systems across environments — from semi-arid rivers to mangrove forests, volcanic coastlines, and urban streams. Using multi-tracer approaches, we find that both natural processes and human activities can significantly impact water quality and ecosystem integrity.

Nitrate tracing: Li et al. (2019); Taillardat et al. (2019); Matiatos et al. (2023)
SGD: Cardenas et al. (2020, GRL)
Acidic streams: Ramchunder et al. (2022)

Publications

Peer-reviewed (* = equal contributions / co-lead / co-corresponding)

2026

36.

Sidle, R.C., Ziegler, A.D., Mosquera, G.M., Evaristo, J., Farrick, K.K., Isaev, E. "Transdisciplinary catchment management in the developing tropics: bridging scientific enquiry with societal needs". Hydrol. Sci. J. DOI: 10.1080/02626667.2026.2647891

35.

Evaristo, J. "Left High and Dry: Deep Soil Water Depletion and Ecohydrological Resilience on China's Loess Plateau". WIREs Water. DOI: 10.1002/wat2.70053 Open Access

34.

Evaristo, J., Wright, C.W., Bauser, H., Knighton, J.K., Johnson, D., Kim, M. "Tracer Labeling and Transit Time Modeling in Soil-Plant Systems…" Ecohydrology. DOI: 10.1002/eco.70182 Open Access

2025

33.

Evaristo, J., Jackson, C.R., Rasmussen, T.C. "Not so isolated: isotopic and hydraulic evidence of vertical connectivity between the Okefenokee Swamp and Floridan Aquifer." Environ. Res.: Water. DOI: 10.1088/3033-4942/ae2653 Open Access

2024

32.

Huang, Y., *Evaristo, J., *Li, Z., et al. "The nature and extent of bomb tritium remaining in vadose zones: a synthesis and prognosis". Vadose Zone J. DOI: 10.1002/vzj2.20304 Open Access

31.

*Ibarra, D.E., *Evaristo, J. "Soil pore water evaporation and temperature influences on clay mineral paleothermometry". Commun. Earth Environ. Link Open Access

30.

Zhao, Y., et al., *Evaristo, J. "Dynamic hydrological niches: how plants compete for water in a seasonally-dry ecosystem". J. Hydrol. DOI: 10.1016/j.jhydrol.2024.130677

29.

Shipley, O.N. … Evaristo, J. … "IsoBank: a centralized repository for isotopic data". PLOS ONE 19(9) DOI: 10.1371/journal.pone.0295662

2023

28.

Evaristo, J., et al. "Water woes: institutional challenges in achieving SDG 6". Sustain. Earth Rev. 6, 13 DOI: 10.1186/s42055-023-00067-2 Open Access

27.

Matiatos, I., et al., Evaristo, J., et al. "Nitrate isotopes in catchment hydrology…" J. Hydrol. DOI: 10.1016/j.jhydrol.2023.130326

26.

Tao, Z., *Evaristo, J., et al. "Tritium and trees: bomb peak perspective on soil water dynamics…" Catena 232 DOI: 10.1016/j.catena.2023.107474 Open Access

2022

25.

Ramchunder, S.J., et al., Evaristo, J., et al. "Flowpath influence on stream acid events in tropical urban streams". Hydrol. Process. 36(1) DOI: 10.1002/hyp.14467

2021

24.

*Knighton, J., et al., *Evaristo, J., et al. "Phylogenetic Underpinning of Groundwater Use by Trees". GRL 48 DOI: 10.1029/2021GL093858 Open Access

23.

Evaristo, J., Jameel, Y., Chun, K.P. "Implication of stem water cryogenic extraction…" PNAS DOI: 10.1073/pnas.2100365118 Open Access

22.

Shi, P., et al., Evaristo, J., Li, Z. "Impacts of deep-rooted fruit trees on deep soil water recharge…" Agric. For. Meteorol. DOI: S0168192321000083

21.

Zhao, Y., et al., Evaristo, J., Wassen, M. "Contrasting adaptive strategies in a semiarid revegetated ecosystem". Agric. For. Meteorol. DOI: S016819232100006X

2020

20.

Xiang, W., Evaristo, J., Li, Z. "Recharge mechanisms of deep soil water revealed by water isotopes…" Geoderma 369 DOI: S0016706119324498

19.

Knighton, J., Singh, K., Evaristo, J. "Understanding Catchment-Scale Forest Root Water Uptake…" GRL DOI: 10.1029/2019GL085937 Open Access

18.

Cardenas, M.B., et al., Evaristo, J. "Submarine groundwater and vent discharge…" GRL DOI: 10.1029/2019GL085730 Open Access

2019 & Earlier

17.

Zhi, L., Evaristo, J., et al. "Spatiotemporal variations in hydrochemical characteristics…" Environ. Pollut. 254 DOI: S0269749119316677

16.

Evaristo, J., et al. "Characterizing fluxes and age distribution of soil water, plant water, and deep percolation…" WRR 55, 3307–3327 DOI: 10.1029/2018WR023265 Open Access

15.

Taillardat, P., et al., Evaristo, J. "Assessing nutrient dynamics in mangrove porewater…" Mar. Chem. 214 DOI: S0304420319300489

14.

Huang, Y., Evaristo, J., Li, Z. "Multiple tracers reveal different groundwater recharge mechanisms…" Geoderma 353 DOI: S0016706119300783

12.

McDonnell, J.J., Evaristo, J. +14 co-authors. "Water sustainability and watershed storage". Nat. Sustain. 1, 378 (2018) Link

Evaristo, J. & McDonnell, J.J. "Prevalence and magnitude of groundwater use by vegetation: a global stable isotope meta-analysis". Sci. Rep. 7, 44110 (2017) Link Open Access

Evaristo, J., Jasechko, S., McDonnell, J.J. "Isotopic composition of plant water sources". Nature 536, E3 (2016) Link

Evaristo, J., Jasechko, S., McDonnell, J.J. "Global separation of plant transpiration from groundwater and streamflow". Nature 525, 91-94 (2015) Link

Teaching

University of Georgia

WASR 4500/6500

Quantitative Methods in Hydrology

3 creditsSenior & GraduateFall semester

Advanced analysis of hydrologic processes — precipitation, evapotranspiration, streamflow, groundwater occurrence and movement, and soil zone flow and transport. Emphasis on quantitative methods with field and laboratory data.

WASR 6200

Rates and Dates: Hydrological Methods and Applications

3 creditsSenior & GraduateFall semester

Explore how scientists use environmental tracers — like isotopes and chemistry — to unravel the movement of water above and belowground, track pollution, and date water and contaminant sources using cutting-edge tools and data science.

WASR 8200

Hillslope Hydrology

3 creditsGraduate onlySpring semester

Intensive, literature-driven and field-based exploration of hillslope hydrology. Students complete a journal-style critical review and collaborative field project synthesizing course concepts.

CRSS/FANR 3060

Soils and Hydrology

3 creditsJuniorSpring semester

Soil formation and morphology, physical and chemical properties, soil-water interactions, hydrologic processes, and water quality. Co-taught with Matt Levi (Soils).

FYOS 1001

Fingerprinting Your Water and Stuff!

1 creditFreshmanFall & Spring

Hands-on introduction to stable and radioactive isotopes as natural "fingerprints" that trace the origins of water and other materials. First-Year Odyssey Seminar.

Service

Professional and institutional service

Editorial Roles

Associate Editor (Jan 2024–), Vadose Zone Journal
Associate Editor (Dec 2023–), Sustainable Earth Reviews
Editorial Board (Apr 2026–), Environmental Research: Water

Grant Review

Panels: US National Science Foundation; Dutch Research Council (NWO)
Ad hoc: Swiss NSF; US NSF; Leverhulme Trust (UK); ANID (Chile); NParks Singapore

Peer Review

Nature · Nature Geoscience · Nature Water · Science · Water Resources Research · Geophysical Research Letters · Journal of Hydrology · Hydrological Processes · WIREs Water · Ecohydrology · Environmental Research Letters · Scientific Reports · New Phytologist · and 20+ additional journals

Institutional

Graduate Program Faculty (Sep 2024–), Graduate Council, University of Georgia
Advisory Board (Jan 2022–), GradMAP Philippines
Staff Representative, Faculty Council, Utrecht University (2023–24)
Education Committee, Water Science & Management MSc, Utrecht University (2021–24)

Submit Samples

Stable isotope analysis services for water and other liquid samples

Lab Facilities

Picarro L2140-i Cavity Ring-Down Spectrometer

Our Picarro L2140-i consistently outperforms factory specifications, achieving δ¹⁸O and δD precision approximately three times better than the manufacturer's guaranteed values. The instrument supports high-throughput, high-precision analysis of water isotopes for hydrology, ecology, and water resources applications.

Rates

Sample Analysis Pricing

Per-sample rates by isotope analysis, sample type, volume tier, and UGA affiliation.

Isotope analysis	Sample type	UGA rate / sample		Outside UGA rate / sample
Isotope analysis	Sample type	1–200 samples	200+ samples	1–200 samples	200+ samples
²H, ¹⁸O	Water	$8.82	$8.82	$9.41	$8.82
²H, ¹⁸O, ¹⁷O	Water	$10.29	$10.29	$10.98	$10.29
²H, ¹⁸O	Other liquids*	$26.45	$26.45	$28.23	$26.45
²H, ¹⁸O, ¹⁷O	Other liquids*	$30.86	$30.86	$32.94	$30.86

*Other liquids = liquids with high total dissolved solids (e.g., plant leaves, stems, juices). Note: Analysis of brackish or brine samples may incur higher rates due to greater consumption of consumables (syringes, septa, salt liners). Please contact us for a custom quote on non-standard sample types.

How to Submit

Get in Touch Before Sending Samples

Please contact Dr. Evaristo for detailed information prior to sample collection and before sending your samples to our lab. This ensures we can advise on appropriate sampling protocols, container types, shipment logistics, and turnaround times for your specific project.

Email: evaristo@uga.edu
Address: Warnell School of Forestry & Natural Resources, University of Georgia, Athens, GA 30602, USA

Utrecht University

2019 – 2024 · Tenured Assistant Professor

From 2019 to 2024, I was a tenured Assistant Professor at Utrecht University in the Netherlands. This page archives my teaching and graduate supervision from that period.

Teaching at Utrecht

GEO4-6009

Sustainable Water Resources Management

7.5 ECTSMasterMain Instructor

Fundamental understanding of catchment functions (partition, storage, release) and hydrological processes in natural and built environments. Students explore sustainable strategies for water resources management using critical thinking, quantitative skills, and management methodologies.

GEO4-6008

Research in Water Science and Management

7.5 ECTSMasterMain Instructor

Considerations, methods, and research best practices in water science and management. Prepares future water sector professionals to formulate and implement reasonable courses of action for complex water issues. Partly prepares students for their master thesis.

GEO2-2131

Ecohydrology

7.5 ECTSBachelorCo-instructor

Scientific analysis of the processes governing the interaction between biota and the hydrological cycle. Practical application through computer modeling of ecohydrological systems at different scales.

GEO1-2412

Natural Processes

7.5 ECTSBachelorCo-instructor

Earth's energy balance, the hydrological cycle, and the elemental cycles of carbon, nitrogen and phosphorus. Major stocks of energy, water, and elements across the atmosphere, hydrosphere, lithosphere, and biosphere.

Graduate Supervision

Total theses supervised at Utrecht: 11 Masters and 9 Bachelors.

Master's Theses

Joren van Os (2023) — Using flexible power in Dutch water pumping stations to balance the energy system
Roos Peeters (2022) Cum Laude — Social Cost-Benefit Analysis of Mangrove Restoration in Mozambique. Thesis. Now Community Engagement Officer at Van Oord.
Peter Beemster (2022) — The SLAMDAM mobile flood barrier as an adaptive measure for building climate resilience against flooding in Sub-Saharan Africa
Daniel Peregrina Gonzalez (2022) — Model-based urban drought hazard assessment using global open data. Thesis
Alice Ampolini (2022) — Inclusion of resilience and flood protection measures to the Urban Climate Risk Index (UCRI). Now Assistant Project Manager at BT Geoconsult.
Jasper van Lieshout (2021) — Modelling alternative drinking water extraction strategies for the sandy Pleistocene regions of the Netherlands. Thesis. Now at Nelen & Schuurmans.
Nathalie van Tricht (2021) — A pro-active regional control system framework for the polder "De Eendragt" in the Netherlands. Thesis
Joey Ewals (2020) — Modelling the effects of the Maaswerken on the drinking water production near Roosteren. Thesis. Now Hydrologist at Waterschap Limburg.
Maureen van Rijn (2020) — Rainproof urban water management in the municipality of Heemskerk. Now Strategy Trainee at Dunea Drinking Water.
Adam Noctor (2020, MSc Sustainable Development) — Identifying the sources of nitrate in surface and ground waters using stable isotopes: A global overview. Thesis
Theresa O'Halloran* (2018, University of Nevada Reno) — Impacts of forest management on hydrologic processes. Thesis. *Committee Member.

Honors Students

Michele Joie Prawiromaruto (MSc Sustainable Development) — Aggregate Confusion of ESG Ratings in the Water Sector. Funded by Bright Minds Assistantships (Apr–Nov 2023).
Mira van Meteren (BSc Global Sustainability Science) — Sights and Sounds of the Unseen: An Audio-Visual Project on Submarine Groundwater Discharge