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Front. Water, 03 April 2024
Sec. Water and Critical Zone
This article is part of the Research Topic Emerging Talents in Water Science: Water and Critical Zone 2021/22 View all 6 articles

Editorial: Emerging talents in water science: water and critical zone 2021/22

  • 1School of Water and Environment, Chang'an University, Xi'an, China
  • 2Key Laboratory of Subsurface Hydrology and Ecological Effects in Arid Region, Ministry of Education, Chang'an University, Xi'an, China
  • 3Xi'an Monitoring, Modelling and Early Warning of Watershed Spatial Hydrology International Science and Technology Cooperation Base, Chang'an University, Xi'an, China
  • 4Climate and Ecosystem Science Division, Berkeley Lab (DOE), Berkeley, CA, United States
  • 5Faculty of Natural Sciences, Institute of Earth Sciences, University of Silesia, Katowice, Poland

1 Introduction

The lack of coordination among different hydrologic subdisciplines has long been a hindrance to the advancement of hydrologic theory and the development of integrated models capable of accurately predicting hydrologic processes across various temporal and spatial scales. However, recent developments in the field have introduced the concept of the “critical zone” (CZ), which represents an open and dynamic system extending from the upper reaches of the canopy down to the depths of the groundwater. This innovative approach serves as a unifying framework that brings together multiple hydrological subdisciplines and integrates them with related physical and ecological sciences (Giardino and Houser, 2015).

The National Research Council (NRC) provided an initial definition in 2001, describing the critical zone as the near-surface environment where interactions between rock, soil, water, air, and living organisms regulate natural habitats and determine resource availability (NRC, 2001; Brantley et al., 2007). Hydrology, which plays a crucial role in the critical zone, specifically the study of water movement, distribution, and quality, is an essential component of understanding the functioning and processes in the critical zone (Latour, 2014). The critical zone is shown in Figure 1.

Figure 1

Figure 1. Schematic representation of the critical zone (Giardino and Houser, 2015).

Hence, to comprehensively grasp the recent strides in the field of water and the critical zone, this Research Topic features a compilation of five papers dedicated to exploring various dimensions of this subject. The collection encompasses studies on the ecohydrology of the critical zone (Moore et al., 2015), isotope hydrology (Guo et al., 2022; Zhou et al., 2022), human impacts on the critical zone (Duan et al., 2021, 2022), and critical zone processes—encompassing physical, chemical, and biological aspects—under the influence of a changing climate (Qin et al., 2022; Zhou et al., 2022). Additionally, the Research Topic delves into critical zone processes responding to alterations in the landscape (Chen G. et al., 2023; Chen X. et al., 2023), among other relevant aspects. This diverse range of papers aims to provide a holistic understanding of the complex interactions between water and the critical zone, offering insights into both natural processes and the anthropogenic influences shaping this vital environmental domain.

The following section concludes the individual articles hosted in this topics in alphabetical order according to the first author's name.

2 Overview of contributions

The five articles included in this topic primarily discuss the role of water as a transformative agent in shaping the structure, processes, and functions of the critical zone. Additionally, they explore water as a response variable, investigating how the composition and dynamics of its flow are influenced by the Critical Zone.

The first article focuses on the biogeochemical properties of soils and their crucial role in soil and stream chemistry within a watershed. It emphasizes the need to understand where and how certain soil water chemical processes occur within a catchment to maintain water quality (Gregory et al.).

The second article highlights the importance of the vertical and lateral extent of the critical zone in providing insights into the chemical and physical processes that connect surface life with geology at depths ranging from 10 to 100 meters (Uecker et al.).

The third article examines the signals transmitted by plant canopies, such as isotopes, sediment types, organisms, and chemical compounds associated with various biogeochemical processes or human impacts. It specifically focuses on the signals conveyed by precipitation draining down the stems of plants (stemflow) (Mabrouk et al.).

The fourth article discusses the significant amount of dissolved organic matter (DOM) transported to the ocean annually from terrestrial sources. It emphasizes the impacts of abiotic and biotic reactions on DOM characteristics and their subsequent effects on biogeochemistry and ecosystem function (Danczak et al.).

The fifth article analyzes a 9-year time series of nutrient cation and anion concentration and efflux from forested catchments in the Jemez River Basin Critical Zone Observatory. It investigates the pulse of chemical denudation resulting from varying levels of stand-replacing wildfire intensity and explores the mechanisms behind this pulsed release and subsequent recovery (Sánchez et al.).

3 Prospect

The critical zone plays a significant role in the formation of extreme weather events caused by climate change in recent years. The critical zone plays a crucial role in regulating water and nutrient cycles and supporting biodiversity, so any disruption due to extreme weather events can have lasting consequences (Wang X. et al., 2023). In the context of extreme weather events, critical zones are closely related to climate change, resulting in many problems such as Hydrological Cycle Disruption (Wang S. et al., 2023), Soil Erosion and Landslides (Wang et al., 2022), Wildfires, Sea Level Rise, Carbon Cycling (Kong et al., 2023), Biodiversity Loss (Weiskopf et al., 2020), Feedback Loops (Qiu et al., 2021).

Overall, the critical zone's interactions with climate change can contribute to the formation and exacerbation of extreme weather events. Understanding these interactions is crucial for developing effective strategies to mitigate the impacts of climate change and enhance the resilience of ecosystems and communities in the face of extreme weather events.

4 Conclusions

The focus on water in this Research Topic acknowledges its multifaceted impact on the Critical Zone. It goes beyond merely viewing water as a passive element affected by the Critical Zone; instead, it emphasizes the reciprocal relationship wherein the Critical Zone actively shapes and is shaped by water dynamics. By delving into this interplay, researchers contributing to this topic aim to enhance our understanding of the intricate connections between water and the Critical Zone, ultimately advancing knowledge in the fields of hydrology, geology, ecology, and beyond.

Author contributions

PL: Writing – original draft, Writing – review & editing. YuZ: Writing – original draft. YiZ: Writing – review & editing. KW: Writing – review & editing. JC: Writing – review & editing. QP: Writing – review & editing.


The author(s) declare that no financial support was received for the research, authorship, and/or publication of this article.


As the Guest Editor of the “Water and Critical Zone” topic, Thanks to all contributing authors. Special thanks to the reviewers for providing timely, thorough reviews and constructive feedback. Lastly, appreciation to the editorial staff for their collaborative and prompt efforts in completing this task.

Conflict of interest

The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest.

The author(s) declared that they were an editorial board member of Frontiers, at the time of submission. This had no impact on the peer review process and the final decision.

Publisher's note

All claims expressed in this article are solely those of the authors and do not necessarily represent those of their affiliated organizations, or those of the publisher, the editors and the reviewers. Any product that may be evaluated in this article, or claim that may be made by its manufacturer, is not guaranteed or endorsed by the publisher.


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Keywords: water and critical zone, climate change, ecohydrology of the critical zone, isotope hydrology, human impacts on the critical zone, critical zone processes

Citation: Luo P, Zhang Y, Zhang Y, Williams KH and Pham QB (2024) Editorial: Emerging talents in water science: water and critical zone 2021/22. Front. Water 6:1374081. doi: 10.3389/frwa.2024.1374081

Received: 21 January 2024; Accepted: 20 March 2024;
Published: 03 April 2024.

Edited and reviewed by: Praveen Kumar, University of Illinois at Urbana-Champaign, United States

Copyright © 2024 Luo, Zhang, Zhang, Williams and Pham. This is an open-access article distributed under the terms of the Creative Commons Attribution License (CC BY). The use, distribution or reproduction in other forums is permitted, provided the original author(s) and the copyright owner(s) are credited and that the original publication in this journal is cited, in accordance with accepted academic practice. No use, distribution or reproduction is permitted which does not comply with these terms.

*Correspondence: Pingping Luo,

Disclaimer: All claims expressed in this article are solely those of the authors and do not necessarily represent those of their affiliated organizations, or those of the publisher, the editors and the reviewers. Any product that may be evaluated in this article or claim that may be made by its manufacturer is not guaranteed or endorsed by the publisher.