Articles | Volume 25, issue 7
Hydrol. Earth Syst. Sci., 25, 3975–3989, 2021
© Author(s) 2021. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Research article 08 Jul 2021
Research article | 08 Jul 2021
Insights into the isotopic mismatch between bulk soil water and Salix matsudana Koidz trunk water from root water stable isotope measurements
Ying Zhao and Li Wang
Related subject area
Subject: Ecohydrology | Techniques and Approaches: Instruments and observation techniquesThe role of dew and radiation fog inputs in the local water cycling of a temperate grassland during dry spells in central EuropeCo-evolution of xylem water and soil water stable isotopic composition in a northern mixed forest biomeVapor plumes in a tropical wet forest: spotting the invisible evaporationRapid reduction in ecosystem productivity caused by flash droughts based on decade-long FLUXNET observationsThroughfall isotopic composition in relation to drop size at the intra-event scale in a Mediterranean Scots pine standRainfall interception and redistribution by a common North American understory and pasture forb, Eupatorium capillifolium (Lam. dogfennel)In situ measurements of soil and plant water isotopes: a review of approaches, practical considerations and a vision for the futureCoalescence of bacterial groups originating from urban runoffs and artificial infiltration systems among aquifer microbiomesA combination of soil water extraction methods quantifies the isotopic mixing of waters held at separate tensions in soilUsing water stable isotopes to understand evaporation, moisture stress, and re-wetting in catchment forest and grassland soils of the summer drought of 2018Partitioning growing season water balance within a forested boreal catchment using sap flux, eddy covariance, and a process-based modelTechnical note: Long-term probe misalignment and proposed quality control using the heat pulse method for transpiration estimationsContribution of understory evaporation in a tropical wet forest during the dry seasonCoffee and shade trees show complementary use of soil water in a traditional agroforestry ecosystemResponses of soil water storage and crop water use efficiency to changing climatic conditions: a lysimeter-based space-for-time approachNeighbourhood and stand structure affect stemflow generation in a heterogeneous deciduous temperate forestTechnical Note: A global database of the stable isotopic ratios of meteoric and terrestrial watersTemporally dependent effects of rainfall characteristics on inter- and intra-event branch-scale stemflow variability in two xerophytic shrubsDissolved organic carbon driven by rainfall events from a semi-arid catchment during concentrated rainfall season in the Loess Plateau, ChinaDew frequency across the US from a network of in situ radiometersSeasonal origins of soil water used by treesForest harvesting impacts on microclimate conditions and sediment transport activities in a humid periglacial environmentHydrogeochemical controls on brook trout spawning habitats in a coastal streamSpeculations on the application of foliar 13C discrimination to reveal groundwater dependency of vegetation and provide estimates of root depth and rates of groundwater useEvaporation from cultivated and semi-wild Sudanian Savanna in west AfricaEvery apple has a voice: using stable isotopes to teach about food sourcing and the water cycleTechnical note: An experimental set-up to measure latent and sensible heat fluxes from (artificial) plant leavesThe spatial distribution and temporal variation of desert riparian forests and their influencing factors in the downstream Heihe River basin, ChinaVariation of soil hydraulic properties with alpine grassland degradation in the eastern Tibetan PlateauChanges in dissolved organic matter quality in a peatland and forest headwater stream as a function of seasonality and hydrologic conditionsComparisons of stemflow and its bio-/abiotic influential factors between two xerophytic shrub speciesRemapping annual precipitation in mountainous areas based on vegetation patterns: a case study in the Nu River basinMonitoring the variations of evapotranspiration due to land use/cover change in a semiarid shrublandThe canopy interception–landslide initiation conundrum: insight from a tropical secondary forest in northern ThailandGroundwater-dependent ecosystems: recent insights from satellite and field-based studiesMonitoring strategies of stream phosphorus under contrasting climate-driven flow regimesHydrological connectivity inferred from diatom transport through the riparian-stream systemMonitoring and modelling of soil–plant interactions: the joint use of ERT, sap flow and eddy covariance data to characterize the volume of an orange tree root zoneDivergence of actual and reference evapotranspiration observations for irrigated sugarcane with windy tropical conditionsUsing measured soil water contents to estimate evapotranspiration and root water uptake profiles – a comparative studyMonitoring of riparian vegetation response to flood disturbances using terrestrial photographyNegative trade-off between changes in vegetation water use and infiltration recovery after reforesting degraded pasture land in the Nepalese Lesser HimalayaThe patterns and implications of diurnal variations in the d-excess of plant water, shallow soil water and air moistureMeasuring and modeling water-related soil–vegetation feedbacks in a fallow plotA comparison of methods for determining field evapotranspiration: photosynthesis system, sap flow, and eddy covarianceImpact of long-term drainage on summer groundwater flow patterns in the Mer Bleue peatland, Ontario, CanadaTraining hydrologists to be ecohydrologists: a "how-you-can-do-it" example leveraging an active learning environment for studying plant–water interactionSpatial variations of shallow and deep soil moisture in the semi-arid Loess Plateau, ChinaSoil moisture and evapotranspiration of different land cover types in the Loess Plateau, ChinaDesert shrub stemflow and its significance in soil moisture replenishment
Yafei Li, Franziska Aemisegger, Andreas Riedl, Nina Buchmann, and Werner Eugster
Hydrol. Earth Syst. Sci., 25, 2617–2648,Short summary
During dry spells, dew and fog potentially play an increasingly important role in temperate grasslands. Research on the combined mechanisms of dew and fog inputs to ecosystems and distillation of water vapor from soil to plant surfaces is rare. Our results using stable water isotopes highlight the importance of dew and fog inputs to temperate grasslands during dry spells and reveal the complexity of the local water cycling in such conditions, including different pathways of dew and fog inputs.
Jenna R. Snelgrove, James M. Buttle, Matthew J. Kohn, and Dörthe Tetzlaff
Hydrol. Earth Syst. Sci., 25, 2169–2186,Short summary
Co-evolution of plant and soil water isotopic composition throughout the growing season in a little-studied northern mixed forest landscape was explored. Marked inter-specific differences in the isotopic composition of xylem water relative to surrounding soil water occurred, despite thin soil cover constraining inter-species differences in rooting depths. We provide potential explanations for differences in temporal evolution of xylem water isotopic composition in this northern landscape.
César Dionisio Jiménez-Rodríguez, Miriam Coenders-Gerrits, Bart Schilperoort, Adriana del Pilar González-Angarita, and Hubert Savenije
Hydrol. Earth Syst. Sci., 25, 619–635,Short summary
During rainfall events, evaporation from tropical forests is usually ignored. However, the water retained in the canopy during rainfall increases the evaporation despite the high-humidity conditions. In a tropical wet forest in Costa Rica, it was possible to depict vapor plumes rising from the forest canopy during rainfall. These plumes are evidence of forest evaporation. Also, we identified the conditions that allowed this phenomenon to happen using time-lapse videos and meteorological data.
Miao Zhang and Xing Yuan
Hydrol. Earth Syst. Sci., 24, 5579–5593,Short summary
We identify flash drought events by considering the decline rate of soil moisture and the drought persistency, and we detect the response of ecosystem carbon and water fluxes to flash droughts based on FLUXNET observations. We find rapid declines in carbon assimilation within 16–24 d of flash drought onset, where savannas show the highest sensitivity. Water use efficiency increases for forests but decreases for herbaceous ecosystems during the recovery stage of flash droughts.
Juan Pinos, Jérôme Latron, Kazuki Nanko, Delphis F. Levia, and Pilar Llorens
Hydrol. Earth Syst. Sci., 24, 4675–4690,Short summary
Water that drips or splashes from a canopy or passes through it is termed throughfall. This is the first known study to examine interrelationships between throughfall isotopic fractionation and throughfall drop size. Working in a mountainous Scots pine forest, we found that throughfall splash droplets were more prevalent at the onset of rain when vapour pressure deficits were larger. This finding has important implications for water mixing in the canopy and for theories of canopy interception.
D. Alex R. Gordon, Miriam Coenders-Gerrits, Brent A. Sellers, S. M. Moein Sadeghi, and John T. Van Stan II
Hydrol. Earth Syst. Sci., 24, 4587–4599,Short summary
Where plants exist, rain must pass through canopies to reach soils. We studied how rain interacts with dogfennel – a highly problematic weed that is abundant in pastures, grasslands, rangelands, urban forests and along highways. Dogfennels evaporated large portions (approx. one-fifth) of rain and drained significant (at times > 25 %) rain (and dew) down their stems to their roots (via stemflow). This may explain how dogfennel survives and even invades managed landscapes during extended droughts.
Matthias Beyer, Kathrin Kühnhammer, and Maren Dubbert
Hydrol. Earth Syst. Sci., 24, 4413–4440,Short summary
Water isotopes are a scientific tool that can be used to identify sources of water and answer questions such as
From which soil depths do plants take up water?, which are highly relevant under changing climatic conditions. In the past, the measurement of water isotopes required tremendous effort. In the last decade methods have advanced and can now be applied in the field. Herein, we review the current status of direct field measurements of water isotopes and discuss future applications.
Yannick Colin, Rayan Bouchali, Laurence Marjolet, Romain Marti, Florian Vautrin, Jérémy Voisin, Emilie Bourgeois, Veronica Rodriguez-Nava, Didier Blaha, Thierry Winiarski, Florian Mermillod-Blondin, and Benoit Cournoyer
Hydrol. Earth Syst. Sci., 24, 4257–4273,Short summary
Stormwater infiltration systems (SISs) are a source of pollution that may have adverse ecological and sanitary impacts. The incidence of a SIS on the coalescence of microbial communities from runoff waters and aboveground sediments with those of an aquifer was investigated. Aquifer waters showed lower coalescence with aboveground bacterial taxa than aquifer biofilms. These biofilms were colonized by bacterial hydrocarbon degraders and harboured undesirable human-opportunistic pathogens.
William H. Bowers, Jason J. Mercer, Mark S. Pleasants, and David G. Williams
Hydrol. Earth Syst. Sci., 24, 4045–4060,Short summary
Determining the chemical composition of soil water can help to address questions concerning water transport and use. However, there are many observations of incompletely mixed soil water within various soil pore domains. We applied two contrasting waters to soil samples and then removed water from the soils with three sequential and increasing applied energy steps to assess soil water mixing and equilibration over time. We found it took more than 3 d for soil water to mix and equilibrate.
Lukas Kleine, Doerthe Tetzlaff, Aaron Smith, Hailong Wang, and Chris Soulsby
Hydrol. Earth Syst. Sci., 24, 3737–3752,Short summary
We investigated the effects of the 2018 drought on water partitioning in a lowland catchment under grassland and forest in north-eastern Germany. Conditions resulted in drying up of streams, yield losses, and lower groundwater levels. Oak trees continued to transpire during the drought. We used stable isotopes to assess the fluxes and ages of water. Sustainable use of resource water requires such understanding of ecohydrological water partitioning.
Nataliia Kozii, Kersti Haahti, Pantana Tor-ngern, Jinshu Chi, Eliza Maher Hasselquist, Hjalmar Laudon, Samuli Launiainen, Ram Oren, Matthias Peichl, Jörgen Wallerman, and Niles J. Hasselquist
Hydrol. Earth Syst. Sci., 24, 2999–3014,Short summary
The hydrologic cycle is one of the greatest natural processes on Earth and strongly influences both regional and global climate as well as ecosystem functioning. Results from this study clearly show the central role trees play in regulating the water cycle of boreal catchments, implying that forest management impacts on stand structure as well as climate change effects on tree growth are likely to have large cascading effects on the way water moves through boreal forested landscapes.
Elisabeth K. Larsen, Jose Luis Palau, Jose Antonio Valiente, Esteban Chirino, and Juan Bellot
Hydrol. Earth Syst. Sci., 24, 2755–2767,Short summary
To improve long-term sap flow measurements when using the heat ratio method, this study introduces a dynamic probe misalignment correction method. This work uses sap flow data from four Aleppo pines from April 2017 to December 2018 and shows how a classical probe correction approach declines in accuracy over time. Additionally, it is proposed that a new set of statistical information be recorded along with the sap flow readings to ensure the quality of the raw data.
César Dionisio Jiménez-Rodríguez, Miriam Coenders-Gerrits, Jochen Wenninger, Adriana Gonzalez-Angarita, and Hubert Savenije
Hydrol. Earth Syst. Sci., 24, 2179–2206,Short summary
Tropical forest ecosystems are able to export a lot of water to the atmosphere by means of evaporation. However, little is known on how their complex structure affects this water flux. This paper analyzes the contribution of three canopy layers in terms of water fluxes and stable water isotope signatures. During the dry season in 2018 the two lower canopy layers provide 20 % of measured evaporation, highlighting the importance of knowing how forest structure can affect the hydrological cycle.
Lyssette Elena Muñoz-Villers, Josie Geris, María Susana Alvarado-Barrientos, Friso Holwerda, and Todd Dawson
Hydrol. Earth Syst. Sci., 24, 1649–1668,Short summary
Our research showed, consistently, a complementary use of soil water sources between coffee (Coffea Arabica var. typica) plants and shade tree species during the dry and wet seasons in a traditional agroforestry ecosystem in central Veracruz, Mexico. However, more variability in plant water sources was observed among species in the rainy season when higher soil moisture conditions were present and water stress was largely absent.
Jannis Groh, Jan Vanderborght, Thomas Pütz, Hans-Jörg Vogel, Ralf Gründling, Holger Rupp, Mehdi Rahmati, Michael Sommer, Harry Vereecken, and Horst H. Gerke
Hydrol. Earth Syst. Sci., 24, 1211–1225,
Johanna C. Metzger, Jens Schumacher, Markus Lange, and Anke Hildebrandt
Hydrol. Earth Syst. Sci., 23, 4433–4452,Short summary
Variation in stemflow (rain water running down the stem) enhances the formation of flow hot spots at the forest floor. Investigating drivers based on detailed measurements, we find that forest structure affects stemflow, both for individual trees and small communities. Densely packed forest patches received more stemflow, due to a higher proportion of woody structure and canopy morphology adjustments, which increase the potential for flow path generation connecting crowns and soil.
Annie L. Putman and Gabriel J. Bowen
Hydrol. Earth Syst. Sci., 23, 4389–4396,Short summary
We describe an open-access, global database of stable water isotope ratios of various water types. The database facilitates data archiving, supports standardized metadata collection, and decreases the time investment for metanalyses. To promote data discovery and collaboration, the database exposes metadata and data owner contact information for private data but only permits download of public data. Two companion apps support digital data collection and processing and upload of analyzed data.
Chuan Yuan, Guangyao Gao, Bojie Fu, Daming He, Xingwu Duan, and Xiaohua Wei
Hydrol. Earth Syst. Sci., 23, 4077–4095,Short summary
The stemflow dynamics of two xerophytic shrubs were investigated at the inter- and intra-event scales with high-temporal-resolution data in 54 rain events. Stemflow process was depicted by intensity, duration and time lags to rain events. Funneling ratio was calculated as the ratio of stemflow to rainfall intensities. Rainfall intensity and raindrop momentum controlled stemflow intensity and time lags. Influences of rainfall characteristics on stemflow variables showed temporal dependence.
Linhua Wang, Haw Yen, Xinhui E, Liding Chen, and Yafeng Wang
Hydrol. Earth Syst. Sci., 23, 3141–3153,Short summary
A high-frequency approach was used to monitor dynamic changes of DOC exported during the concentrated rainfall season in LPR, China. DOC concentration and flux from an ecologically restored catchment in the LPR was investigated. Hysteresis analysis indicated non-linear relationships between DOC concentration and discharge rate in a rainfall event. DOC export is substantially affected by the interaction of rainfall and antecedent conditions for a rainfall event.
François Ritter, Max Berkelhammer, and Daniel Beysens
Hydrol. Earth Syst. Sci., 23, 1179–1197,Short summary
There currently is no standardized approach for measuring dew formation, making it difficult to compare its frequency and importance across ecosystems. Recently, canopy surface temperature data from 30 sites in the US were measured continuously using in situ infrared radiometers. The analysis presented here provides the first continental-scale standardized synthesis of dew formation. This work provides a basis for considering how changing climate and land use will influence dew formation.
Scott T. Allen, James W. Kirchner, Sabine Braun, Rolf T. W. Siegwolf, and Gregory R. Goldsmith
Hydrol. Earth Syst. Sci., 23, 1199–1210,Short summary
We used stable isotopes of xylem water to study differences in the seasonal origin of water in more than 900 individual trees from three dominant species in 182 Swiss forested sites. We discovered that midsummer transpiration was mostly supplied by winter precipitation across diverse humid climates. Our findings provide new insights into tree vulnerability to droughts, transport of water (and thus solutes) in soils, and the climatic information conveyed by plant-tissue isotopes.
Fumitoshi Imaizumi, Ryoko Nishii, Kenichi Ueno, and Kousei Kurobe
Hydrol. Earth Syst. Sci., 23, 155–170,Short summary
We investigated seasonal changes in sediment transport activities following forest harvesting in a humid periglacial area. Removal of the forest canopy by forest harvesting alters the type of winter soil creep. Winter creep velocity of the ground surface sediment in the harvested site was significantly higher than that in the non-harvested site. Meanwhile, sediment flux on the hillslopes decreased in the harvested site because of capture of sediment by branches of harvested trees.
Martin A. Briggs, Judson W. Harvey, Stephen T. Hurley, Donald O. Rosenberry, Timothy McCobb, Dale Werkema, and John W. Lane Jr.
Hydrol. Earth Syst. Sci., 22, 6383–6398,Short summary
Brook trout are known to seek out groundwater-discharge zones for spawning. However, in a groundwater-dominated system, we observed trout using a few locations for repeatedly laying eggs. To improve the management of this cold-water species, we wanted to know why these specific groundwater-discharge zones were desirable. Through a combination of geophysical and chemical measurements, we found that locations where the stream intersects the sandy valley wall create oxygen-rich seepage zones.
Rizwana Rumman, James Cleverly, Rachael H. Nolan, Tonantzin Tarin, and Derek Eamus
Hydrol. Earth Syst. Sci., 22, 4875–4889,Short summary
Groundwater is a significant water resource for humans and for groundwater-dependent vegetation. Several challenges to managing both groundwater resources and dependent vegetation include defining the location of dependent vegetation, the rate of groundwater use, and the depth of roots accessing groundwater. In this study we demonstrate a novel application of measurements of stable isotopes of carbon that can be used to identify the location, the rooting depth, and the rate of groundwater use.
Natalie C. Ceperley, Theophile Mande, Nick van de Giesen, Scott Tyler, Hamma Yacouba, and Marc B. Parlange
Hydrol. Earth Syst. Sci., 21, 4149–4167,Short summary
We relate land cover (savanna forest and agriculture) to evaporation in Burkina Faso, west Africa. We observe more evaporation and temperature movement over the savanna forest in the headwater area relative to the agricultural section of the watershed. We find that the fraction of available energy converted to evaporation relates to vegetation cover and soil moisture. From the results, evaporation can be calculated where ground-based measurements are lacking, frequently the case across Africa.
Erik Oerter, Molly Malone, Annie Putman, Dina Drits-Esser, Louisa Stark, and Gabriel Bowen
Hydrol. Earth Syst. Sci., 21, 3799–3810,Short summary
Fruits take up soil water as they grow, and thus the fruit water is related to the rain or irrigation the crop receives. We used a novel sampling system to measure the stable isotopes of H and O in the fruit water to determine its geographic origin by comparing it to maps of isotopes in rain. We used this approach to teach an audience of science students and teachers about water cycle concepts and how humans may modify the water cycle through agriculture and irrigation water diversions.
Stanislaus J. Schymanski, Daniel Breitenstein, and Dani Or
Hydrol. Earth Syst. Sci., 21, 3377–3400,Short summary
Leaf transpiration and energy exchange are coupled processes at the small scale that have strong effects on the water cycle and climate at the large scale. In this technical note, we present a novel experimental set-up that enables detailed study of these coupled processes in the laboratory under controlled conditions. Results document the abilities of the experimental set-up to confirm or challenge our understanding of these processes.
Jingyi Ding, Wenwu Zhao, Stefani Daryanto, Lixin Wang, Hao Fan, Qiang Feng, and Yaping Wang
Hydrol. Earth Syst. Sci., 21, 2405–2419,Short summary
In this study, we focused on exploring the spatial distribution and temporal variation of desert riparian forests and their influencing factors based on field experiment and remote sensing data. Our result revealed how the environmental factors shape the spatial distribution and temporal variation of desert riparian forest in the downstream Heihe river. The results of this study provide support for the effective restoration of desert riparian forest in the hyperarid zone.
Tao Pan, Shuai Hou, Shaohong Wu, Yujie Liu, Yanhua Liu, Xintong Zou, Anna Herzberger, and Jianguo Liu
Hydrol. Earth Syst. Sci., 21, 2249–2261,Short summary
This study shows that soil hydraulic properties, especially those of the top soil, varied greatly with alpine swamp meadow degradation. Soil porosity is the dominant influencing factor of soil hydraulic properties. The results suggest that alpine swamp meadow degradation would inevitably lead to negative hydrological effects. Hydrological modelling in the Tibetan Plateau and similar regions are recommended to understand the effects of degradation on soil hydraulic properties.
Tanja Broder, Klaus-Holger Knorr, and Harald Biester
Hydrol. Earth Syst. Sci., 21, 2035–2051,Short summary
This study elucidates controls on temporal variability in DOM concentration and quality in stream water draining a bog and a forested peaty riparian zone, particularly considering drought and storm flow events. DOM quality was monitored using spectrofluorometric indices (SUVA254, SR and FI) and PARAFAC modeling of EEMs. DOM quality depended clearly on hydrologic preconditions and season. Moreover, the forested peaty riparian zone generated most variability in headwater DOM quantity and quality.
Chuan Yuan, Guangyao Gao, and Bojie Fu
Hydrol. Earth Syst. Sci., 21, 1421–1438,Short summary
We computed stemflow yield and efficiency, and analyzed the influential mechanism at smaller scales of leaf and raindrop. We found that precipitation was the most influential meteorological feature on stemflow. The smaller threshold precipitation to start stemflow and the more beneficial leaf traits might partly explain the larger and more efficient stemflow production. At defoliated period, the newly exposed stems replaced leaves to intercept raindrops and might really matter in stemflow yield.
Xing Zhou, Guang-Heng Ni, Chen Shen, and Ting Sun
Hydrol. Earth Syst. Sci., 21, 999–1015,Short summary
We develop a fusion framework to improve precipitation estimation by jointly utilizing the gauge precipitation and vegetation index and then applying them to mountainous areas of the Nu River basin. The results demonstrate the reliability of the framework in reproducing the high-resolution precipitation regime and capturing its high spatial variability in the Nu River basin. The framework can significantly reduce the errors in precipitation estimates as compared with the IDW and TRMM methods.
Tingting Gong, Huimin Lei, Dawen Yang, Yang Jiao, and Hanbo Yang
Hydrol. Earth Syst. Sci., 21, 863–877,Short summary
Seasonal and inter-annual features of ET were analyzed over four periods. A normalization method was adopted to exclude the effects of potential evapotranspiration and soil water stress on ET. During the land degradation process, when natural vegetation (including leaves and branches), sand dunes, dry sand layers, and BSCs were all bulldozed, ET was observed to increase at a mild rate. In a vegetation rehabilitation process with sufficient groundwater, ET also increased at a faster rate.
Roy C. Sidle and Alan D. Ziegler
Hydrol. Earth Syst. Sci., 21, 651–667,Short summary
Rainwater intercepted by forest canopies has been suggested to moderate peak pulses of rainfall and resultant pore pressure within soils, thus reducing the risk of shallow landslides. Three years of data in a tropical secondary forest in northern Thailand show that average canopy interception during large storms was only 7 % of rainfall. These peak rain inputs had little effect on soil moisture pulses below 1 m. Thus, canopy interception would have little effect in mitigating shallow landslides.
D. Eamus, S. Zolfaghar, R. Villalobos-Vega, J. Cleverly, and A. Huete
Hydrol. Earth Syst. Sci., 19, 4229–4256,Short summary
In this review, we discuss a range of techniques, including remote sensing, for identifying groundwater-dependent ecosystems and determining rates of water use by GDEs. In addition, gravity recovery satellite data are discussed in relation to changes in soil and groundwater stores. Ecophysiological and structural attributes of GDEs are reviewed, from which we present an integrated ecosystem-scale response as a function of differences in depth-to-groundwater.
G. Goyenola, M. Meerhoff, F. Teixeira-de Mello, I. González-Bergonzoni, D. Graeber, C. Fosalba, N. Vidal, N. Mazzeo, N. B. Ovesen, E. Jeppesen, and B. Kronvang
Hydrol. Earth Syst. Sci., 19, 4099–4111,Short summary
Climate and hydrology are relevant control factors determining the timing and amount of nutrient losses from land to aquatic systems, in particular of phosphorus (P) from agricultural lands. The main objective of the study was to evaluate the differences in P export patterns and the performance of alternative monitoring strategies in streams under contrasting climate-driven flow regimes: temperate and stable discharge conditions (Denmark) and sub-tropical and flashy conditions (Uruguay).
N. Martínez-Carreras, C. E. Wetzel, J. Frentress, L. Ector, J. J. McDonnell, L. Hoffmann, and L. Pfister
Hydrol. Earth Syst. Sci., 19, 3133–3151,Short summary
We tested the hypothesis that different diatom species assemblages inhabit specific moisture domains of the catchment and, consequently, the presence of certain species assemblages in the stream during runoff events offers the potential for recording whether there was hydrological connectivity between these domains or not. In the Weierbach catchment, the transport of aerial diatoms during events suggested a rapid connectivity between the soil surface and the stream.
G. Cassiani, J. Boaga, D. Vanella, M. T. Perri, and S. Consoli
Hydrol. Earth Syst. Sci., 19, 2213–2225,Short summary
The paper presents an integrated approach to monitoring root water uptake and link this information to the plant transpiration measured by sap flow and eddy covariance. The monitoring of soil conditions is achieved using 3-D electrical resistivity tomography. This ensemble of data can be used jointly to model the soil-plant interactions and identify the extent and efficiency of the root zone in front of existing irrigation schemes. A case study is presented regarding an orange orchard in Sicily.
R. G. Anderson, D. Wang, R. Tirado-Corbalá, H. Zhang, and J. E. Ayars
Hydrol. Earth Syst. Sci., 19, 583–599,Short summary
Evapotranspiration (ET) was measured and compared to reference ET over irrigated sugarcane in Hawaii, USA: reference ET increasingly diverged from measured ET with higher wind conditions; custom bulk canopy resistance improved reference ET observations; the Priestley-Taylor equation performed better than reference ET to estimate actual ET; bulk canopy resistance was over 150 s/m, but there was no evidence of water stress in the field.
M. Guderle and A. Hildebrandt
Hydrol. Earth Syst. Sci., 19, 409–425,Short summary
This paper is the result of a numerical study to test the application of water balance methods for estimating evapotranspiration and water extraction profiles based on measured soil water content data. The advantage of the tested methods is that they do not rely on a priori information of any root distribution parameters. Our research shows the potential of water balance methods for derivation of water extraction profiles, but their application may be challenging in realistic conditions.
K. Džubáková, P. Molnar, K. Schindler, and M. Trizna
Hydrol. Earth Syst. Sci., 19, 195–208,Short summary
We use a high-resolution ground-based camera system with near-infrared sensitivity to quantify the response of riparian vegetation in an Alpine river to floods with the use of vegetation indices. The vegetation showed both damage and enhancement within 1 week following floods, with a selective impact determined by pre-flood vegetation vigour, morphological setting and intensity of flood forcing. The tested vegetation indices differed in the direction of predicted change in the range 0.7-35.8%.
C. P. Ghimire, L. A. Bruijnzeel, M. W. Lubczynski, and M. Bonell
Hydrol. Earth Syst. Sci., 18, 4933–4949,
L. Zhao, L. Wang, X. Liu, H. Xiao, Y. Ruan, and M. Zhou
Hydrol. Earth Syst. Sci., 18, 4129–4151,
N. Ursino, G. Cassiani, R. Deiana, G. Vignoli, and J. Boaga
Hydrol. Earth Syst. Sci., 18, 1105–1118,
Z. Zhang, F. Tian, H. Hu, and P. Yang
Hydrol. Earth Syst. Sci., 18, 1053–1072,
B. J. Kopp, J. H. Fleckenstein, N. T. Roulet, E. Humphreys, J. Talbot, and C. Blodau
Hydrol. Earth Syst. Sci., 17, 3485–3498,
S. W. Lyon, M. T. Walter, E. J. Jantze, and J. A. Archibald
Hydrol. Earth Syst. Sci., 17, 269–279,
L. Yang, W. Wei, L. Chen, F. Jia, and B. Mo
Hydrol. Earth Syst. Sci., 16, 3199–3217,
S. Wang, B. J. Fu, G. Y. Gao, X. L. Yao, and J. Zhou
Hydrol. Earth Syst. Sci., 16, 2883–2892,
X.-P. Wang, Z.-N. Wang, R. Berndtsson, Y.-F. Zhang, and Y.-X. Pan
Hydrol. Earth Syst. Sci., 15, 561–567,
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Allen, S. T., Kirchner, J. W., Braun, S., Siegwolf, R. T. W., and Goldsmith, G. R.: Seasonal origins of soil water used by trees, Hydrol. Earth Syst. Sci., 23, 1199–1210, https://doi.org/10.5194/hess-23-1199-2019, 2019.
Barbeta, A., Jones, S. P., Clavé, L., Wingate, L., Gimeno, T. E., Fréjaville, B., Wohl, S., and Ogée, J.: Unexplained hydrogen isotope offsets complicate the identification and quantification of tree water sources in a riparian forest, Hydrol. Earth Syst. Sci., 23, 2129–2146, https://doi.org/10.5194/hess-23-2129-2019, 2019.
Barbeta, A., Gimeno, T. E., Clave, L., Frejaville, B., Jones, S. P., Delvigne, C., Wingate, L., and Ogee, J. M.: An explanation for the isotopic offset between soil and stem water in a temperate tree species, New Phytol., 227, 766–779, 2020.
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At our study site during the experimental period, trunk water was only isotopically similar to root water at 100–160 cm depths. The isotopic composition of root water deviated from that of bulk soil water but overlapped with the composition derived for less mobile water. These findings suggest that the isotopic offset between bulk soil water and trunk water was due to the isotopic mismatch between root water and bulk soil water associated with soil water heterogeneity.
At our study site during the experimental period, trunk water was only isotopically similar to...