Naizin or Kervidy-Naizin and Kerbernez, Brittany, France 1975-
- 1 Location and Scale
- 2 Dates
- 3 Climate
- 4 Geology
- 5 Topography and soils
- 6 Vegetation / Land Use
- 7 History
- 8 Hydrological and biogeochemical Knowledge Gained
- 9 Interdisciplinary approaches
- 10 Links and review papers
- 11 References
Location and Scale
The Kervidy-Naizin catchment covers 5 km2 in central Brittany (latitude, 47.95; longitude, −2.8; WGS84). A second site, the Kerbernez site, is a complementary site. It is composed of a network of seven catchments with areas between 0.1 and 0.6 km in southwestern Brittany (latitude, 47.94; longitude, −4.1; WGS84). The two sites constitute the AgrHyS ERO (https://www6.inrae.fr/ore_agrhys_eng/) and they are headwater catchments and first- and second-order streams.
From the early 1970s to the present
The AgrHyS observatory of response times in agro-hydro systems, located in western France, is dedicated to the observation of agro-hydrosystems under a temperate climate characterized by shallow groundwater and intensive agriculture, mainly of annual crops receiving a high amount of mineral and organic inputs. AgrHyS is composed of instrumented catchments where environmental variables are monitored over the long term to study the processes controlling hydro-chemical fluxes in agro-ecosystems, with the objective of characterizing their response time to climatic and agricultural impacts. On the two sites research has been conducted since the early 1970s. In 2002, AgrHyS was declared by the French Ministry of Research as an Environmental Research Observatory (ERO). Gascuel-Odoux et al. (2018) analyzes the coevolution of research topics with observatories and methods used in Environmental Sciences based on the 50-yr history of the Kervidy Naizin site. Fovet et al (2020) highlights the synergies between the observations at the two sites based on the review of the missions and accomplishments of AgrHyS hydrological observatory since. These long-term observatories serve different missions and have several objectives: facilitate research, provide reference data sets, test methodologies, train new scientists, and educate the public. AgrHys is currently integrated in The French Network of Critical Zone Observatories created in 2017 (Gaillardet et al., 2018).
The climate is temperate and humid at both sites with a regional west–east gradient between sites. Average value calculated over 30 years are given below, for Kervidy-Naizain and Kerbernez, respectively. Rainfall, mm yr−1 837 ± 219 1114 ± 237 Penman potential evapotranspiration, mm yr−1 699 ± 58 680 ± 29 Temperature, °C Average 11.2 ± 0.6 12.0 ± 0.5 Maximal 32.6 ± 3.2 30.7 ± 2.6 Minimal −5.0 ± 2.0 −5.8 ± 5.4 Annual runoff, mm yr−1 325 ± 186 227 ± 115 to 448 ± 304
The geological bedrock consists of low-permeability crystalline rocks with a similar structure: above the impervious bedrock there is a fissured and fractured layer in which water is likely to percolate deeply. The fractured layer is mantled by a weathered layer where shallow groundwater can fluctuate. In the Kervidy-Naizin site, the bedrock is composed of upper Proterozoic schists, whereas in the Kerbernez site it is granite known as the Leucogranodiorite of Plomelin. The two major bedrock types of the Brittany region are thus represented by the two sites. The weathered zone is 1 to 30 m deep in the Kervidy-Naizin site, with hydraulic conductivity ranging from 4.10−6 to 2.10−5 m s−1 and 40 to 50% total porosity. In the Kerbernez site, the weathered layer is 20 to 40 m deep, with hydraulic conductivity between 2.10−6 and 5.10−4 m s−1 and 42 to 60% total porosity.
Topography and soils
Slopes are gentle at both sites (<5% on average). The soils are silty loams in Kervidy-Naizin between 0.5 and 1.5 m deep, and in Kerbernez there is mainly sandy loam that is 0.8 m deep on average. Soils are well-drained except in bottomlands close to the streams, where water excess leads to hydromorphic, poorly drained soils and Albeluvisols. Soil hydraulic conductivity at saturation ranges from 10−5 to 10−6 m s−1 in Kervidy-Naizin and from 10−5 to 10−4 ms−1 in Kerbernez. The superficial soil layers (0–40 cm in Kervidy-Naizin and 0–20 cm in Kerbernez) are rich in organic matter (2.5–6.5% in Kervidy-Naizin and 4.5–6% in Kerbernez).
Vegetation / Land Use
Land use is dominated by intensive agriculture, with systems mixing cropping and indoor dairy and pig farming. In 2013, these catchments were mainly covered by maize, straw cereals, and grasslands. In Kervidy-Naizin these main land cover types correspond to 38, 30, and 15% of arable area, respectively, whereas in Kerbernez they vary between 10 and 70%, between 5 and 24%, and between 0 and 6% of arable area, respectively, depending on the catchment. In some Kerbernez catchments, the number of abandoned or converted fields (i.e., into a golf course) is increasing. To further interpret and model nutrient transfer over catchments, detailed information includes crop rotations (to control land cover maps and to fill potential gaps in them), fertilizer application, pesticide application, crop residues management, livestock size and types, animal feeding, and manure and dejection management. On the Kerbernez site, where each catchment is composed of a few fields only, the survey is focused on the two most instrumented catchments and is conducted every 4 yr. On the Kervidy-Naizin site, which includes 47 farms, three detailed surveys were conducted: in 1993 (Cheverry, 1998), in 2008 and in 2013, this last one specifically on dynamics of organic matter investigated the cropping systems (i.e., crop rotations and crop management practices at the field scale for each farm) (Viaud et al., 2018).
Hydrological settings The current observation protocol of AgrHyS consists of long-term records of meteorological, hydrological, and hydro-chemical variables and land cover maps. The longest time series started in 1993. Since that date, the Kerbernez and Kervidy-Naizin sites have been equipped with a weather station that records hourly rainfall, air and soil temperatures, air humidity, global radiation, and wind direction and speed, which allows the calculation of daily Penman evapotranspiration. Between 1995 and 1997, the outlets were equipped with U-notch or V-notch weirs for monitoring the stream water level. Most gauging stations are automated and use float-operated sensors that record stream level sub-hourly (from 1 to 10 min). Since 1999, the level sensors have been connected to a data logger. From 1997 to 2005, a network of piezometers was installed in the two sites to monitor shallow groundwater fluctuations and variations in its chemical composition. Currently, 31 piezometers are monitored on the two sites. The water table level is measured using automatic transducer sensors, sometimes coupled with temperature and electrical conductivity sensors that record water table data every 15 min in most piezometers (and manually in the others every month).
Various elemental concentrations are analyzed in the water depending on the station: major anions (Cl, NO2, NO3, SO4), major cations (Ca, Mg, K, Na), dissolved organic C (DOC) and dissolved inorganic C (sometimes coupled with Fe), total and soluble reactive phosphorus, and suspended solids. These concentrations are measured using grab sampling mostly. Various water quality parameters are also measured using sensors (electrical conductivity, temperature, turbidity, NO3 and DOC concentrations, and total reactive and total P concentrations). Grab samples have been conducted since 1993 in the stream to collect in situ standard physicochemical data. Monitoring has been intensified since 1999. Rain water composition has been investigated since 2010. The highest frequency of sampling in the stream (Kervidy-Naizin) is 1 d since 1999, and the highest frequency of groundwater sampling (Kerbernez piezometers) is 1 wk (between 2005 and 2012). Automatic samplers are used to sample storm flow events every 10 to 30 min over 10 h, which is consistent with the duration of such events in the catchments. Between 4 and 10 events are monitored every year. Since 2007, some complementary, nearly continuous (15–10 min) monitoring of physicochemical variables has been conducted using dedicated sensors: turbidity and concentrations of NO3, organic C, and P in stream water and temperature and electrical conductivity in stream and groundwater.
The evolution of land cover from one year to another is obtained by farm survey or in-field observations or is reconstructed from remote data by analyzing and classifying the information contained in images. The main annual land use in each field is recorded, at least in the case of cover crops. The land cover maps over the period 1993 to 2018 account for the modifications of the field limit over time. In addition to these data, additional observations are conducted for the duration of the project or even through several successive projects, leading to dedicated medium- to long-term data sets.
The first soil maps were established in the early stages of the research sites (Lamandé, 2003; Walter, 1993) to provide an extensive description of the spatial organization of soils and connect them to their hydrological and geochemical functioning (Walter and Curmi, 1998). High-resolution soil maps (1:10,000 and 1:25,000) have been established on the basis of four criteria: soil parent material, soil depth, soil redoximorphic conditions, and soil types as defined in the French soil classification (Baize et al., 2002). The physicochemical properties of soils (texture, pH, nutrient content, organic matter, trace elements) have been measured over the catchment, and hydrodynamic properties of soil horizons (hydraulic conductivity, porosity) have been quantified for the main soil types. In more recent research projects, additional soil collection campaigns have been conducted in the Kervidy-Naizin site to quantify C, N, and P stocks in the soil compartment and to characterize the biochemical processes controlling C, N, and P cycling in soils. Detailed data on soil C, N, and P content; soil aggregation; and microbial communities (molecular microbial biomass estimated by soil DNA recovery, bacterial and fungal communities analyzed by 16S and 18S rRNA gene pyrosequencing) (Matos-Moreira et al., 2017) have been collected. Soil moisture sensors have been in use since 2010 in specific locations of the catchments and according to different strategies. At the Kerbernez site, 21 frequency domain reflectometry sensors are coupled with nested piezometers to monitor the groundwater recharge process. At the Kervidy-Naizin sites, time domain reflectometry sensors (often coupled with temperature sensors) are used either on soil profile (at −5, −20, and −50 cm deep) or in the upper layer of soil (−5 cm) to interpret measurements of gaseous fluxes (CO2, N2O) conducted in successive research projects. The time step of acquisition ranges from 15 to 30 min.
Recharge water was sampled using profiles of ceramic cups between −25 cm and −2.5 m on which suction was applied for water collection. At the Kervidy-Naizin site, the chemical composition of soil water has been investigated since 2011 focused on organic matter and P. Bottomland soils and wetland soils have been instrumented with zero-tension lysimeters and mini-piezometers to allow the sampling of free water in soils (Denis et al., 2017a, 2017b; Dupas et al., 2015c; Gu et al., 2017; Lambert et al., 2011). These samples are analyzed to determine their concentrations in anions, dissolved C (and Fe), and dissolved P, in addition to any other variables of interest.
Surface–Atmosphere Exchange Fluxes
A flux tower station was installed in 2015 over grazed grassland, recording surface/atmosphere H2O and CO2 fluxes continuously over a few years to capture their seasonal and interannual variability. During the day, CO2 fluxes are linked to H2O fluxes via photosynthesis and transpiration of the vegetation, which is controlled by bulk canopy stomatal conductance; during the night soil and plant respiration proceed. Fluxes are measured by eddy covariance, and a set of ancillary meteorological and soil variables is recorded on site. The measurement height is 2 m, corresponding to a flux footprint of the order of 1 to 3 ha depending on wind speed, atmospheric turbulence, and stability.
Analyzing Water Chemistry at Higher Temporal Resolution
Several technologies have been or are being tested regarding their ability to provide water concentrations at resolution >1 h. Sensors that estimate concentrations using indirect methods including in situ ionic specific probes and spectrophotometric probes were installed in 2010 to monitor NO3, Cl, and organic C concentrations. They have been tested in stream and piezometers, leading to satisfactory results for the spectrophotometer, which records NO3 and dissolved organic C every 15 min (Faucheux and Fovet, 2014). Ionic specific probes have been found more reliable for spatial campaigns than for continuous monitoring at a given point. The most recent generation of tools is based on river bank side analyzers, which pump water directly from the stream and determine concentrations by direct physicochemical methods equivalent to those used in the laboratory in real time, avoiding storage and transport issues. A P analyzer has recorded total and reactive P in the Kervidy-Naizin site since 2016 every 30 min (Jordan et al., 2007). The challenge to increase the temporal resolution of analysis for various chemical elements in water is also taken up with the development of a river laboratory prototype (Floury et al., 2017). A second prototype measures major ion concentrations (by ionic chromatography), dissolved silica (colorimetry), and organic C (acid mineralization and infrared CO2 measurement) approximately every 30 min in stream water at the outlet of the Kervidy-Naizin site.
Dedicated campaigns and experiments
Campaigns for Dynamic Mapping of Wetlands in Space and Time. According to their role in overland flow generation (Beven and Kirkby, 1979) and their role as hot spots for biogeochemical reactions (Sabater et al., 2003), wetlands have been the subject of several research projects. Wetlands result from the combination of climate, topography, and geomorphology zones in areas where the water table intercepts shallow soil horizons (Crave and Gascuel-Odoux, 1997). Such combinations are dynamic in space and time. Wetlands inventories have been made on the field by visual identification and by helicopter-borne radar (Gineste et al., 1998; Merot et al., 1994). Thanks to the inventory, a method for mapping those wetlands from a digital elevation model and using a climate-topographic index (Merot et al., 2003) has been developed.
Geophysical Campaigns and Experimental Determination of Hydrodynamic Properties.
To characterize the hydrodynamic properties of the weathered rock, slug tests and pumping tests were performed in some of the piezometers to provide estimates of hydraulic conductivity (Martin et al., 2006; Molenat and Gascuel-Odoux, 2002; Molénat et al., 2005; Pauwels, 1994; Vouillamoz, 2003).In the Kerbernez site, these tests were combined with geophysical surveys (electrical imaging, electromagnetic and magnetic resonance sounding) and indicate that the thickness of the weathered granite increases from upslope toward downslope areas of the catchments in the form of a deep graben structure (Legchenko et al., 2004). Subsequently, an experimental determination of weathered material was performed using the Wind method (Rouxel et al., 2012), showing that the retention curve of weathered granite is different from soil retention curves and cannot be easily estimated using pedotransfer function approaches.
Tracer Experiments and Use of Geochemical and Isotopic Tools.
Hydrological and geochemical deconvolution can use various tracers to identify contributive flowpaths and biogeochemical reaction processes or to estimate water and element residence times in catchment compartments such as soil, vadose zone, or groundwater. Various tracers have been used for different objectives. In the Kervidy-Naizin site, a lot of projects were dedicated to storm flow generation and associated exports of dissolved organic matter (DOM). Storm flow deconvolutions based on water isotopes (18O) showed the small portion of recent water in storm hydrographs (Merot et al., 1995), pointing to the importance of old water from soil and groundwater in the genesis of storm flow. Then, several tracer approaches were used and compared to identify and quantify the contributions of different compartments to DOC export during storm events and thereby also to improve our understanding of subsurface flows. The 13C of C (Lambert et al., 2011, 2013, 2014), the fluorescence signature, and the molecular composition of DOM (Denis et al., 2017a; Jeanneau et al., 2014) confirmed the major contribution of riparian wetlands to storm DOC and emphasized a secondary contribution of downslope areas, which decreased along successive storms. The fluorescence signature also emphasized the potential direct contribution of animal manure to the stream DOM during intense spring storm events. In the Kerbernez sites, tracer experiments have been conducted to gain a better understanding in groundwater recharge. The first attempt to use 2H in tracer campaigns at the scale of shallow piezometers was not conclusive, most likely because of excessive transfer times. Tracer experiments with Br and 2H helped to estimate the water velocity in soils and showed the bimodal properties of the velocities. Enzymatic activity was also used in combination with solute concentrations in laboratory experiments to characterize the biogeochemically reactive transfer in the soil and the weathered zone, showing that heterotrophic denitrification was the dominant process (Legout et al., 2005, 2007). Groundwater age was determined using atmospheric tracer chlorofluorocarbons and SF6, highlighting the distinction between the weathered zone (where apparent ages ranged from 12 to 25 yr) and the weathered-fissured and fractured parts (where apparent age increased with depth and was >25 yr) (Ayraud et al., 2008; Molénat et al., 2013). In both catchments, shallow groundwater feeds the streams; therefore, different experimental tools have been explored to quantify the subsurface fluxes and their temporal or spatial variations. Preliminary tests on radon were started in 2015, and studies on temperature using distributed temperature sensing by optic fiber were started in 2016. Atmospheric Emissions and Deposition. Several campaigns have been conducted since 2007 to assess various fluxes, such as CO2, N2O, and NH3, at the landscape scale. For example, Buysse et al. (2016) measured soil CO2 efflux with closed dynamic respiration chambers over a 1-yr period (36 weekly to biweekly measurement dates) at 22 sites across the Kervidy-Naizin catchment. They found that water regime, land-use, and crop rotation significantly affect soil CO2 emissions, with lower emissions observed in poorly drained soils either due to lower respiration or to limited CO2 transport in saturated soils. A network of passive and low-cost sensors for atmospheric ammonia (NH3), which integrates concentrations over monthly periods, was also established across the catchment (Tang et al., 2001). These low-resolution atmospheric NH3 data were complemented by mobile NH3 plume measurement campaigns, downwind of the main agricultural NH3 sources (animal housing), using fast-response (1 s) quantum cascade laser technology. These datasets were used to improve landscape-scale estimates of total NH3 emissions as well as local dry deposition, which contribute significantly to the total N load of agroecosystems in areas of intensive animal farming (Bell, 2017).
Hydrological and biogeochemical Knowledge Gained
Over the years, the research conducted on the two sites has contributed to new insights into the hydrological sciences. In the early stages (1990–2000), novel findings highlighted the role of landscape geomorphology on water flowpaths and their dynamics. This was achieved by assessing the role of bottomlands on surface flows (Merot and Bruneau, 1993) and then refining the delineation of variable contributive area concepts (Crave and Gascuel-Odoux, 1997; Merot et al., 1994, 1995), studying the effect of hillslope geomorphology (Beaujouan et al., 2001) and then the role of hedgerow network (Benhamou et al., 2013; Merot, 1999; Viaud et al., 2005) on water and dissolved N fluxes. Kervidy-Naizin also hosted several pioneer studies of hydrograph separations (Durand and Torres 1996; Merot et al., 1995; Morel et al., 2009) that were continued later using DOM as a tracer of water pathways (Denis et al., 2017a, 2017b; Jeanneau et al., 2014; Lambert et al., 2011). Another key contribution highlights shallow groundwater seasonal and its interannual fluctuations as a major driver of hydrological and chemical fluxes in such crystalline systems by controlling fluxes and storages (Martin et al., 2006; Molenat and Gascuel-Odoux, 2001; Molenat et al., 2008; Ruiz et al., 2002a, 2002b) as well as the connectivity (Dupas et al., 2015a, 2015b; Humbert et al. submitted, Fovet et al., 2018; Gu, 2017) and the onset of specific biogeochemical processes (e.g., reductive dissolution of soil Fe oxides that induce nitrate reduction or P release) or location of biogeochemically reactive hot spots in the landscape (Grybos et al., 2009; Lambert et al., 2014; Legout et al., 2007; Oehler et al., 2009). This key role of shallow groundwater is of major importance because it reveals high response times of surface water quality to changes in agricultural inputs in such agro-ecosystems (Ayraud et al., 2008; Fovet et al., 2015b; Molenat and Gascuel-Odoux, 2002, Molénat et al., 2013;). Indeed, transit times of water and solutes have been shown to be very variable and much higher than expected considering that, in such systems with a hard rock aquifer and oceanic climate, subsurface pathways are rather short and storage capacity is low compared with annual drainage.
These contributions also enhance the biogeochemical sciences with original characterization of fractured schist reactivity (Pauwels, 1994) and unique characterization of groundwater age in shallower parts of a weathered aquifer (Ayraud et al., 2008; de Montéty et al., 2018). Due to their specificity of human activities with intensive agriculture, including farming systems, these catchments were also a unique opportunity to investigate the effect of local anthropization on weathering and acidification processes (Pierson-Wickmann et al., 2009a, 2009b), which have been mostly studied in pristine areas. These sites have also supported considerable work on the biogeochemistry of wetland soils, including OM, Fe, rare Earth elements, and P speciation, and combined controls exerted by soil characteristics, hydroclimate variability, and topography on the occurrence and intensity of biogeochemical reactions in those soils (Davranche et al., 2011, 2013, 2015; Gu et al., 2017, 2018; Grybos et al., 2007, 2009; Pourret et al., 2007, 2010). Finally, research conducted on these catchments led to major contributions in highlighting and quantifying the role of wetland soils on the export of DOM and P in headwater lowland catchments on impervious bedrock (Gu et al., 2017; Humbert et al., 2015; Lambert et al., 2013; Morel et al., 2009).
After a decade of observations, these catchments started to offer a unique opportunity to conduct long-term analyses, in particular for investigating the effect of seasonal, interannual, and pluriannual variability of climatic features and farming practices on water and nutrient fluxes. Original data treatments methods and approaches to unravel such effects have been tested and developed on this unique data set (Aubert et al., 2013b,c, 2014; Dupas et al., 2015b). Detailed analyses of how seasonality is structured over the climatic interannual variability and how it structures the catchment behavior regarding chemical elements was only possible thanks to daily long records at daily frequency (Humbert et al., 2015) combined with storm records at sub-hourly frequency (Dupas et al., 2015a, 2015b; Vongvixay et al., 2018). Modeling studies are also strongly enriched with such long-term and multiparameter and multicompartment data sets (Fovet et al., 2015a; Salmon-Monviola et al., 2013) because they offer a unique case for testing how well the model is constrained and how realistic it behaves regarding multiple criteria (Fovet et al., 2015a; Hrachowitz et al., 2014).
A major feature of these catchments are their role in support of interdisciplinary approaches. They are unique in their ability to make researchers from various disciplines work together on both scientific and technical or methodological issues. Since the beginning, they have been designed with an interdisciplinary approach combining the monitoring of hydro-meteorological variables and of water quality parameters with soil characterization (Le Bissonnais et al., 2002; Matos-Moreira et al., 2017; Walter, 1993) and agricultural systems description and understanding. They have helped to realize that understanding the relations between agriculture and environment despite nonstationary conditions (climate variability) and buffering effects due to residence times and biogeochemical transformations requires integrative approaches that involve hydrology, biogeochemistry, soil science, geophysics, bioclimatology, agricultural science, and ecology. The long-term dimension of the observatory is crucial here because building such integrative science needs time and has been possible because of shared field work and shared perceptual models between researchers from various disciplines on those sites. Therefore, these catchments are a major lever for building up and accumulating knowledge on agro-ecosystems, to understand their complexity, their huge range of spatial and temporal scales at which the key controlling processes operate, and the strong unsteadiness of its forcing variables (i.e., climate and human activities).
Links and review papers
Fovet, O. et al., 2018. AgrHyS: An Observatory of Response Times in Agro-Hydro Systems. Vadose Zone Journal, 17(1). DOI:10.2136/vzj2018.04.0066
Gaillardet, J. et al., 2018. OZCAR: The French Network of Critical Zone Observatories. Vadose Zone Journal, 17(1). DOI:10.2136/vzj2018.04.0067
Gascuel-Odoux, C., Fovet, O., Gruau, G., Ruiz, L., Merot, P., 2018. Evolution of scientific questions over 50 years in the Kervidy-Naizin catchment: from catchment hydrology to integrated studies of biogeochemical cycles and agroecosystems in a rural landscape. 2018. DOI:10.18172/cig.3383
Aquilina, L. et al., 2015. Impact of climate changes during the last 5 million years on groundwater in basement aquifers. Scientific Reports, 5. DOI:10.1038/srep14132
Aubert, A., Merot, P., Gascuel, C., 2015. Temporal patterns of water quality: decadal high-frequency data-driven analysis from an hydrological observatory under agricultural land-use. La Houille Blanche - Revue internationale de l'eau(6): 5-11. DOI:10.1051/lhb/20150062
Aubert, A.H., 2013. Analyse des motifs temporels d’une chronique décennale haute-fréquence de qualité de l’eau dans un observatoire agro-hydrologique. Thèse de doctorat Thesis, Agrocampus Ouest, 159 p. pp.
Aubert, A.H. et al., 2013a. Solute transport dynamics in small, shallow groundwater-dominated agricultural catchments: insights from a high-frequency, multisolute 10 yr-long monitoring study. Hydrology and Earth System Sciences, 17(4): 1379-1391. DOI:10.5194/hess-17-1379-2013
Aubert, A.H., Gascuel-Odoux, C., Merot, P., 2013b. Annual hysteresis of water quality: A method to analyse the effect of intra- and inter-annual climatic conditions. Journal of Hydrology, 478: 29-39. DOI:10.1016/j.jhydrol.2012.11.027
Aubert, A.H. et al., 2014. Fractal Water Quality Fluctuations Spanning the Periodic Table in an Intensively Farmed Watershed. Environmental Science & Technology, 48(2): 930-937. DOI:10.1021/es403723r
Aubert, A.H. et al., 2013c. Clustering flood events from water quality time series using Latent Dirichlet Allocation model. Water Resour. Res., 49(12): 8187-8199. DOI:10.1002/2013wr014086
Ayraud, V. et al., 2008. Compartmentalization of physical and chemical properties in hard-rock aquifers deduced from chemical and groundwater age analyses. Applied Geochemistry, 23(9): 2686-2707. DOI:10.1016/j.apgeochem.2008.06.001
Basset-Mens, C., Anibar, L., Durand, P., van der Werf, H.M.G., 2006. Spatialised fate factors for nitrate in catchments: Modelling approach and implication for LCA results. Science of the Total Environment, 367(1): 367-382. DOI:http://dx.doi.org/10.1016/j.scitotenv.2005.12.026
Beaujouan, V., Durand, P., Ruiz, L., Aurousseau, P., Cotteret, G., 2002. A hydrological model dedicated to topography-based simulation of nitrogen transfer and transformation: rationale and application to the geomorphology-denitrification relationship. Hydrological Processes, 16(2): 493-507. DOI:10.1002/hyp.327
Benettin, P., Fovet, O., Li, L., 2020. Nitrate removal and young stream water fractions at the catchment scale. Hydrological Processes, 34(12): 2725-2738. DOI:10.1002/hyp.13781
Benhamou, C., Salmon-Monviola, J., Durand, P., Grimaldi, C., Merot, P., 2013. Modeling the interaction between fields and a surrounding hedgerow network and its impact on water and nitrogen flows of a small watershed. Agricultural Water Management, 121(0): 62-72. DOI:http://dx.doi.org/10.1016/j.agwat.2013.01.004
Bhaduri, B., Sekhar, M., Fovet, O., Ruiz, L., 2022. Estimating solute travel times from time series of nitrate concentration in groundwater: Application to a small agricultural catchment in Brittany, France. Journal of Hydrology, 613: 128390. DOI:https://doi.org/10.1016/j.jhydrol.2022.128390
Birgand, F. et al., 2010. Uncertainties in assessing annual nitrate loads and concentration indicators: Part 1. Impact of sampling frequency and load estimation algorithms. Transactions of the Asabe, 53(2): 437-446.
Birgand, F. et al., 2009. Une approche quantitative du rôle de la fréquence d'échantillonnage sur les incertitudes associées aux calculs des flux et des concentrations moyennes en nitrate en Bretagne. . Ingénieries, 59(60): 23-37.
Birgand, F., Faucheux, C., Gruau, G., Moatar, F., Meybeck, M., 2011. Uncertainties in assessing annual nitrate loads and concentration indicators: Part 2. Deriving sampling frequency charts in Brittany, France. Transactions of the Asabe, 54(1): 93-104.
Bougon, N. et al., 2012. Influence of depth and time on diversity of free-living microbial community in the variably saturated zone of a granitic aquifer. FEMS Microbiology Ecology, 80(1): 98-113. DOI:10.1111/j.1574-6941.2011.01273.x
Braud, I. et al., 2020. Building the information system of the French Critical Zone Observatories network: Theia/OZCAR-IS. Hydrological Sciences Journal: 1-19. DOI:10.1080/02626667.2020.1764568
Brun, C. et al., 1990. Mapping saturated areas with a helicopter-borne c band scatterometer. Water Resour. Res., 26(5): 945-955. DOI:10.1029/89wr03627
Bruneau, P., Gascuelodoux, C., Robin, P., Merot, P., Beven, K., 1995. Sensitivity to space and time resolution of a hydrological model using digital elevation data. Hydrological Processes, 9(1): 69-81. DOI:10.1002/hyp.3360090107
Buysse, P., Flechard, C.R., Hamon, Y., Viaud, V., 2016. Impacts of water regime and land-use on soil CO2 efflux in a small temperate agricultural catchment. Biogeochemistry, 130(3): 267-288. DOI:10.1007/s10533-016-0256-y
Carluer, N., Marsily, G.D., 2004. Assessment and modelling of the influence of man-made networks on the hydrology of a small watershed: implications for fast flow components, water quality and landscape management. Journal of Hydrology, 285(1): 76-95. DOI:https://doi.org/10.1016/j.jhydrol.2003.08.008
Casal, L. et al., 2019a. Reduction of stream nitrate concentrations by land management in contrasted landscapes. Nutrient Cycling in Agroecosystems, 114(1): 1-17. DOI:10.1007/s10705-019-09985-0
Casal, L. et al., 2019b. Optimal location of set-aside areas to reduce nitrogen pollution: a modelling study. The Journal of Agricultural Science, 156(9): 1090-1102. DOI:10.1017/S0021859618001144
Caubel, V., Grimaldi, C., Merot, P., Grimaldi, M., 2003. Influence of a hedge surrounding bottomland on seasonal soil-water movement. Hydrological Processes, 17(9): 1811-1821. DOI:10.1002/hyp.1214
Chaplot, V., Walter, C., 2003. Subsurface topography to enhance the prediction of the spatial distribution of soil wetness. Hydrological Processes, 17(13): 2567-2580. DOI:10.1002/hyp.1273
Chaplot, V., Walter, C., Curmi, P., 2003. Testing Quantitative Soil-Landscape Models for Predicting the Soil Hydromorphic Index At A Regional Scale. Soil Science, 168(6): 445-454.
Cognard, A.-L. et al., 1995. Evaluation of the ERS 1/Synthetic Aperture Radar Capacity to Estimate Surface Soil Moisture: Two-Year Results Over the Naizin Watershed. Water Resour. Res., 31(4): 975-982. DOI:10.1029/94wr03390
Crave, A., GascuelOdoux, C., 1997. The influence of topography on time and space distribution of soil surface water content. Hydrological Processes, 11(2): 203-210. DOI:10.1002/(sici)1099-1085(199702)11:2<203::aid-hyp432>3.0.co;2-k
Curmi, P. et al., 1997. Rôle du sol sur la circulation et la qualité des eaux au sein de paysages présentant un domaine hydromorphe. Incidences sur la teneur en nitrate des eaux superficielles d'un bassin versant armoricain. Etude et Gestion des Sols, 4(2): 95-114.
Curmi, P. et al., 1995. Le programme CORMORAN-INRA : de l'importance du milieu physique dans la régulation biogéochimique de la teneur en nitrate des eaux superficielles. Journal européen d'hydrologie, 26(1): 37-56.
Curmi, P. et al., 1998. Hydromorphic soils, hydrology and water quality: spatial distribution and functional modelling at different scales. Nutrient Cycling in Agroecosystems, 50(1-3): 127-142. DOI:10.1023/a:1009775825427
Dalgaard, T. et al., 2012. Farm nitrogen balances in six European landscapes as an indicator for nitrogen losses and basis for improved management. Biogeosciences, 9(12): 5303-5321. DOI:10.5194/bg-9-5303-2012
Darboux, F., Davy, P., Gascuel-Odoux, C., 2002a. Effect of depression storage capacity on overland-flow generation for rough horizontal surfaces: water transfer distance and scaling. Earth Surface Processes and Landforms, 27(2): 177-191. DOI:10.1002/esp.312
Darboux, F., Gascuel-Odoux, C., Davy, P., 2002b. Effects of surface water storage by soil roughness on overland-flow generation. Earth Surface Processes and Landforms, 27(3): 223-233. DOI:10.1002/esp.313
Dausse, A., Merot, P., Bouzille, J.B., Bonis, A., Lefeuvre, J.C., 2005. Variability of nutrient and particulate matter fluxes between the sea and a polder after partial tidal restoration, Northwestern France. Estuar. Coast. Shelf Sci., 64(2-3): 295-306. DOI:10.1016/j.ecss.2005.02.023
Davranche, M. et al., 2013. Organic matter control on the reactivity of Fe(III)-oxyhydroxides and associated As in wetland soils: A kinetic modeling study. Chemical Geology, 335(0): 24-35. DOI:http://dx.doi.org/10.1016/j.chemgeo.2012.10.040
Davranche, M. et al., 2014. Biogeochemical Factors Affecting Rare Earth Element Distribution in Shallow Wetland Groundwater. Aquat. Geochem.: 1-19. DOI:10.1007/s10498-014-9247-6
Davranche, M. et al., 2015. Biogeochemical Factors Affecting Rare Earth Element Distribution in Shallow Wetland Groundwater. Aquat. Geochem., 21(2): 197-215. DOI:10.1007/s10498-014-9247-6
Davranche, M. et al., 2011. Rare earth element patterns: A tool for identifying trace metal sources during wetland soil reduction. Chemical Geology, 284(1–2): 127-137. DOI:http://dx.doi.org/10.1016/j.chemgeo.2011.02.014
Davranche, M., Pourret, O., Gruau, G., Dia, A., Le Coz-Bouhnik, M., 2005. Adsorption of REE(III)-humate complexes onto MnO2: Experimental evidence for cerium anomaly and lanthanide tetrad effect suppression. Geochimica Et Cosmochimica Acta, 69(20): 4825-4835. DOI:http://dx.doi.org/10.1016/j.gca.2005.06.005
De Lavenne, A., Boudhraa, H., Cudennec, C., 2015. Streamflow prediction in ungauged basins through geomorphology-based hydrograph transposition. Hydrology Research, 46(2): 291 - 302. DOI:10.2166/nh.2013.099
De Lavenne, A., Boudhraâ, H., Cudennec, C., 2013. Streamflow prediction in ungauged basins through geomorphology-based hydrograph transposition. Hydrology Research In Press, Uncorrected Proof DOI:10.2166/nh.2013.099
de Montety, V. et al., 2018. Recharge processes and vertical transfer investigated through long-term monitoring of dissolved gases in shallow groundwater. Journal of Hydrology, 560: 275-288. DOI:https://doi.org/10.1016/j.jhydrol.2018.02.077
Denis, M. et al., 2017a. New molecular evidence for surface and sub-surface soil erosion controls on the composition of stream DOM during storm events. Biogeosciences, 14(22): 5039-5051. DOI:10.5194/bg-14-5039-2017
Denis, M. et al., 2017b. A comparative study on the pore-size and filter type effect on the molecular composition of soil and stream dissolved organic matter. Organic Geochemistry, 110(Supplement C): 36-44. DOI:https://doi.org/10.1016/j.orggeochem.2017.05.002
Derrien, M., 2011. Validation de l'utilisation des stéroïdes en tant qu'outil de traçage de l'origine des contaminations fécales des eaux de surface, Université Rennes 1, 281 p. pp.
Dia, A. et al., 2000. The distribution of rare earth elements in groundwaters: assessing the role of source-rock composition, redox changes and colloidal particles. Geochimica Et Cosmochimica Acta, 64(24): 4131-4151. DOI:http://dx.doi.org/10.1016/S0016-7037(00)00494-4
Drouet, J.L., Duretz, S., Durand, P., Cellier, P., 2012. Modelling the contribution of short-range atmospheric and hydrological transfers to nitrogen fluxes, budgets and indirect emissions in rural landscapes. Biogeosciences, 9(5): 1647-1660. DOI:10.5194/bg-9-1647-2012
Dupas, R., Gascuel-Odoux, C., Gilliet, N., Grimaldi, C., Gruau, G., 2015a. Distinct export dynamics for dissolved and particulate phosphorus reveal independent transport mechanisms in an arable headwater catchment. Hydrological Processes, 29(14): 3162-3178. DOI:10.1002/hyp.10432
Dupas, R. et al., 2015b. Groundwater control of biogeochemical processes causing phosphorus release from riparian wetlands. Water Research, 84: 307-314. DOI:10.1016/j.watres.2015.07.048
Dupas, R. et al., 2017. The role of mobilisation and delivery processes on contrasting dissolved nitrogen and phosphorus exports in groundwater fed catchments. Science of the Total Environment, 599–600: 1275-1287. DOI:https://doi.org/10.1016/j.scitotenv.2017.05.091
Dupas, R. et al., 2016. Uncertainty assessment of a dominant-process catchment model of dissolved phosphorus transfer. Hydrology and Earth System Sciences, 20(12): 4819-4835. DOI:10.5194/hess-20-4819-2016
Dupas, R. et al., 2015c. Identifying seasonal patterns of phosphorus storm dynamics with dynamic time warping. Water Resour. Res., 51(11): 8868-8882. DOI:10.1002/2015wr017338
Durand, P., 2004. Simulating nitrogen budgets in complex farming systems using INCA: calibration and scenario analyses for the Kervidy catchment (W. France). Hydrol. Earth Syst. Sci., 8(4): 793-802. DOI:10.5194/hess-8-793-2004
Durand, P., Gascuel-Odoux, C., Cordier, M.-O., 2002. Parameterisation of hydrological models: a review and lessons learned from studies of an agricultural catchment (Naizin, France). Agronomie, 22(2): 217-228.
Durand, P., Gascuel-Odoux, C., Kao, C., Merot, P., 2000. Une typologie des petites zones humides ripariennes. Etude et Gestion des Sols, 7(3): 207-218.
Durand, P., Torres, J.L.J., 1996. Solute transfer in agricultural catchments: The interest and limits of mixing models. Journal of Hydrology, 181(1-4): 1-22. DOI:10.1016/0022-1694(95)02922-2
Duretz, S. et al., 2011. NitroScape: A model to integrate nitrogen transfers and transformations in rural landscapes. Environmental Pollution, 159(11): 3162-3170. DOI:http://dx.doi.org/10.1016/j.envpol.2011.05.005
Fakih, M., 2008. Biogéochimie du fer et des éléments associés : Exemple de l'arsenic (V), Université Rennes 1, 161 p. pp.
Fakih, M. et al., 2009. Environmental impact of As(V)-Fe oxyhydroxide reductive dissolution: An experimental insight. Chemical Geology, 259(3-4): 290-303. DOI:10.1016/j.chemgeo.2008.11.021
Fakih, M. et al., 2008. A new tool for in situ monitoring of Fe-mobilization in soils. Applied Geochemistry, 23(12): 3372-3383. DOI:http://dx.doi.org/10.1016/j.apgeochem.2008.07.016
Faucheux, M., Fovet, O., 2014. Mesures in situ et à haute fréquence de la chimie d’un cours d’eau par spectrophotométrie UV-visible. Le Cahier Technique de l'INRA, 82(2): 1-15.
Fekiacova, Z., Pichat, S., Cornu, S., Balesdent, J., 2013. Inferences from the vertical distribution of Fe isotopic compositions on pedogenetic processes in soils. Geoderma, 209: 110-118. DOI:10.1016/j.geoderma.2013.06.007
Ferrant, S. et al., 2011. Understanding nitrogen transfer dynamics in a small agricultural catchment: Comparison of a distributed (TNT2) and a semi distributed (SWAT) modeling approaches. Journal of Hydrology, 406(1-2): 1-15. DOI:10.1016/j.jhydrol.2011.05.026
Flechard, C.R. et al., 2011. Dry deposition of reactive nitrogen to European ecosystems: a comparison of inferential models across the NitroEurope network. Atmos. Chem. Phys., 11(6): 2703-2728. DOI:10.5194/acp-11-2703-2011
Fovet, O. et al., 2021. Intermittent rivers and ephemeral streams: Perspectives for critical zone science and research on socio-ecosystems. WIREs Water, 8(4): e1523. DOI:https://doi.org/10.1002/wat2.1523
Fovet, O. et al., 2018a. Seasonal variability of stream water quality response to storm events captured using high-frequency and multi-parameter data. Journal of Hydrology, 559: 282-293. DOI:https://doi.org/10.1016/j.jhydrol.2018.02.040
Fovet, O. et al., 2015a. Using long time series of agricultural-derived nitrates for estimating catchment transit times. Journal of Hydrology, 522: 603-617. DOI:10.1016/j.jhydrol.2015.01.030
Fovet, O. et al., 2018b. AgrHyS: An Observatory of Response Times in Agro-Hydro Systems. Vadose Zone Journal, 17(1). DOI:10.2136/vzj2018.04.0066
Fovet, O., Ruiz, L., Hrachowitz, M., Faucheux, M., Gascuel-Odoux, C., 2015b. Hydrological hysteresis and its value for assessing process consistency in catchment conceptual models. Hydrology and Earth System Sciences, 19(1): 105-123. DOI:10.5194/hess-19-105-2015
Franks, S.W., Gineste, P., Beven, K.J., Merot, P., 1998. On constraining the predictions of a distributed moder: The incorporation of fuzzy estimates of saturated areas into the calibration process. Water Resour. Res., 34(4): 787-797. DOI:10.1029/97wr03041
Frei, R.J. et al., 2020. Predicting Nutrient Incontinence in the Anthropocene at Watershed Scales. Frontiers in Environmental Science, 7(200). DOI:10.3389/fenvs.2019.00200 Gaillardet, J. et al., 2018. OZCAR: The French Network of Critical Zone Observatories. Vadose Zone Journal, 17(1). DOI:10.2136/vzj2018.04.0067
Gascuel-Odoux, C. et al., 2009. A decision-oriented model to evaluate the effect of land use and agricultural management on herbicide contamination in stream water. Environmental Modelling & Software, 24(12): 1433-1446. DOI:http://dx.doi.org/10.1016/j.envsoft.2009.06.002
Gascuel-Odoux, C. et al., 2011. Incorporating landscape features to obtain an object-oriented landscape drainage network representing the connectivity of surface flow pathways over rural catchments. Hydrological Processes, 25(23): 3625-3636. DOI:10.1002/hyp.8089
Gascuel-Odoux, C., Aurousseau, P., Durand, P., Ruiz, L., Molenat, J., 2010a. The role of climate on inter-annual variation in stream nitrate fluxes and concentrations. Science of the Total Environment, 408(23): 5657-5666. DOI:10.1016/j.scitotenv.2009.05.003
Gascuel-Odoux, C., Fovet, O., Faucheux, M., Salmon-Monviola, J., Strohmenger, L., 2023. How to assess water quality change in temperate headwater catchments of western Europe under climate change: examples and perspectives. Comptes Rendus. Géoscience. DOI:10.5802/crgeos.147
Gascuel-Odoux, C., Fovet, O., Gruau, G., Ruiz, L., Merot, P., 2018. Evolution of scientific questions over 50 years in the Kervidy-Naizin catchment: from catchment hydrology to integrated studies of biogeochemical cycles and agroecosystems in a rural landscape. 2018. DOI:10.18172/cig.3383
Gascuel-Odoux, C. et al., 2007. Rôle des prairies dans les pollutions diffuses. Effet de la localisation et des bordures (haies, dispositifs enherbés, berges) Fourrages, 192: 409-422.
Gascuel-Odoux, C., Merot, P., Durand, P., Molenat, J., 1999. Génèse des crues normales dans les petits bassins versants ruraux - Normal runoff generation in small agricultural catchments. Houille Blanche-Rev. Int., 54(7-8): 54-60.
Gascuel-Odoux, C., Weiler, M., Molenat, J., 2010b. Effect of the spatial distribution of physical aquifer properties on modelled water table depth and stream discharge in a headwater catchment. Hydrology and Earth System Sciences, 14(7): 1179-1194. DOI:10.5194/hess-14-1179-2010
Gineste, P., Puech, C., Merot, P., 1998. Radar remote sensing of the source areas from the Coet-Dan catchment. Hydrological Processes, 12(2): 267-284. DOI:10.1002/(sici)1099-1085(199802)12:2<267::aid-hyp576>3.0.co;2-g
Grimaldi, C., Baudry, J., Pinay, G., 2012. Des zones tampons dans les paysages ruraux pour la régulation de la pollution diffuse. (Buffer zones in rural landscapes for regulation of diffuse pollution). Innovations Agronomiques, 23: 55-68.
Gruau, G., Dia, A., Olivié-Lauquet, G., Davranche, M., Pinay, G., 2004. Controls on the distribution of rare earth elements in shallow groundwaters. Water Research, 38(16): 3576-3586. DOI:http://dx.doi.org/10.1016/j.watres.2004.04.056
Grybos, M., Davranche, M., Gruau, G., Petitjean, P., 2007. Is trace metal release in wetland soils controlled by organic matter mobility or Fe-oxyhydroxides reduction? Journal of Colloid and Interface Science, 314(2): 490-501. DOI:http://dx.doi.org/10.1016/j.jcis.2007.04.062
Grybos, M., Davranche, M., Gruau, G., Petitjean, P., Pédrot, M., 2009. Increasing pH drives organic matter solubilization from wetland soils under reducing conditions. Geoderma, 154(1–2): 13-19. DOI:http://dx.doi.org/10.1016/j.geoderma.2009.09.001
Gu, S., Gruau, G., Dupas, R., Jeanneau, L., 2020. Evidence of colloids as important phosphorus carriers in natural soil and stream waters in an agricultural catchment. Journal of Environmental Quality, 49(4): 921-932. DOI:https://doi.org/10.1002/jeq2.20090
Gu, S. et al., 2019. Respective roles of Fe-oxyhydroxide dissolution, pH changes and sediment inputs in dissolved phosphorus release from wetland soils under anoxic conditions. Geoderma, 338: 365-374. DOI:https://doi.org/10.1016/j.geoderma.2018.12.034
Gu, S. et al., 2017. Release of dissolved phosphorus from riparian wetlands: Evidence for complex interactions among hydroclimate variability, topography and soil properties. Science of the Total Environment, 598: 421-431. DOI:10.1016/j.scitotenv.2017.04.028
Gu, S. et al., 2018. Drying/rewetting cycles stimulate release of colloidal-bound phosphorus in riparian soils. Geoderma, 321: 32-41. DOI:10.1016/j.geoderma.2018.01.015
Guénet, H. et al., 2017. Highlighting the wide variability in arsenic speciation in wetlands: A new insight into the control of the behavior of arsenic. Geochimica Et Cosmochimica Acta, 203: 284-302. DOI:10.1016/j.gca.2017.01.013
Guénet, H. et al., 2016. Evidence of organic matter control on As oxidation by iron oxides in riparian wetlands. Chemical Geology, 439: 161-172. DOI:10.1016/j.chemgeo.2016.06.023
Guénet, H. et al., 2018. Experimental evidence of REE size fraction redistribution during redox variation in wetland soil. Science of The Total Environment, 631-632: 580-588. DOI:https://doi.org/10.1016/j.scitotenv.2018.03.005
Hrachowitz, M. et al., 2016. Transit times the link between hydrology and water quality at the catchment scale. Wiley Interdiscip. Rev.-Water, 3(5): 629-657. DOI:10.1002/wat2.1155
Hrachowitz, M. et al., 2014. Process consistency in models: The importance of system signatures, expert knowledge, and process complexity. Water Resour. Res., 50(9): 7445-7469. DOI:10.1002/2014wr015484
Hrachowitz, M., Fovet, O., Ruiz, L., Savenije, H.H.G., 2015. Transit time distributions, legacy contamination and variability in biogeochemical 1/f(alpha) scaling: how are hydrological response dynamics linked to water quality at the catchment scale? Hydrological Processes, 29(25): 5241-5256. DOI:10.1002/hyp.10546
Humbert, G., Jaffrezic, A., Fovet, O., Gruau, G., Durand, P., 2015. Dry-season length and runoff control annual variability in stream DOC dynamics in a small, shallow groundwater-dominated agricultural watershed. Water Resour. Res., 51(10): 7860-7877. DOI:10.1002/2015wr017336
Humbert, G. et al., 2020. Agricultural Practices and Hydrologic Conditions Shape the Temporal Pattern of Soil and Stream Water Dissolved Organic Matter. Ecosystems, 23(7): 1325-1343. DOI:10.1007/s10021-019-00471-w
Jaffrezic, A., Merot, P., 1998. Empirical modelling of the oxidoreduction potential variations in a hydromorphic organic soil. Mineralogical Magazine, 62A: 703-704.
Jeanneau, L. et al., 2020. Water Table Dynamics Control Carbon Losses from the Destabilization of Soil Organic Matter in a Small, Lowland Agricultural Catchment. Soil Systems, 4(1): 2. DOI:https://doi.org/10.3390/soilsystems4010002
Jeanneau, L. et al., 2014. Constraints on the Sources and Production Mechanisms of Dissolved Organic Matter in Soils from Molecular Biomarkers. Vadose Zone Journal, 13(7). DOI:10.2136/vzj2014.02.0015
Lambert, T., 2013. Sources, production et transfert du carbone organique dissous dans les bassins versants élémentaires sur socle : apports des isotopes stables du carbone, Université Rennes 1, 165 p. pp.
Lambert, T. et al., 2013. Hydrologically driven seasonal changes in the sources and production mechanisms of dissolved organic carbon in a small lowland catchment. Water Resour. Res.: n/a-n/a. DOI:10.1002/wrcr.20466
Lambert, T., Pierson-Wickmann, A.-C., Gruau, G., Thibault, J.-N., Jaffrezic, A., 2011. Carbon isotopes as tracers of dissolved organic carbon sources and water pathways in headwater catchments. Journal of Hydrology, 402(3-4): 228-238. DOI:10.1016/j.jhydrol.2011.03.014
Lambert, T. et al., 2014. DOC sources and DOC transport pathways in a small headwater catchment as revealed by carbon isotope fluctuation during storm events. Biogeosciences, 11(11): 3043-3056. DOI:10.5194/bg-11-3043-2014
Le Guillou, C. et al., 2019. Tillage intensity and pasture in rotation effectively shape soil microbial communities at a landscape scale. MicrobiologyOpen, 8(4): e00676. DOI:10.1002/mbo3.676
Lefrançois, J., 2007. Dynamiques et origines des matières en suspension sur de petits bassins versants agricoles sur schiste. Thèse de l'universtié Thesis, Université de Rennes 1, 261 p. pp.
Legchenko, A. et al., 2004. Magnetic Resonance Sounding Applied to Aquifer Characterization. Ground Water, 42(3): 363-373. DOI:10.1111/j.1745-6584.2004.tb02684.x
Legout, C. et al., 2007. Solute transfer in the unsaturated zone-groundwater continuum of a headwater catchment. Journal of Hydrology, 332(3-4): 427-441. DOI:10.1016/j.jhydrol.2006.07.017
Legout, C., Molenat, J., Lefebvre, S., Marmonier, P., Aquilina, L., 2005. Investigation of biogeochemical activities in the soil and unsaturated zone of weathered granite. Biogeochemistry, 75(2): 329-350. DOI:10.1007/s10533-005-0110-0
Leterme, P., Barre, C., Vertes, F., 2003. The fate of 15N from dairy cow urine under pasture receiving different rates of N fertiliser. Agronomie, 23(7): 609-616.
Lofts, S., Tipping, E., Hamilton-Taylor, J., 2008. The Chemical Speciation of Fe(III) in Freshwaters. Aquat. Geochem., 14(4): 337-358. DOI:10.1007/s10498-008-9040-5
Lotfi-Kalahroodi, E. et al., 2019. Iron isotope fractionation in iron-organic matter associations: Experimental evidence using filtration and ultrafiltration. Geochimica et Cosmochimica Acta, 250: 98-116. DOI:https://doi.org/10.1016/j.gca.2019.01.036
Lotfi-Kalahroodi, E. et al., 2021. More than redox, biological organic ligands control iron isotope fractionation in the riparian wetland. Scientific Reports, 11(1): 1933. DOI:10.1038/s41598-021-81494-z
Marsac, R., 2011. Contrôle de la spéciation des terres rares par les acides humiques : rôle de l'hétérogénéité des sites de complexation et de la compétition entre cations, Université Rennes 1, 157 p. pp.
Martin, C. et al., 2004. Seasonal and interannual variations of nitrate and chloride in stream waters related to spatial and temporal patterns of groundwater concentrations in agricultural catchments. Hydrological Processes, 18(7): 1237-1254. DOI:10.1002/hyp.1395
Martin, C. et al., 2006. Modelling the effect of physical and chemical characteristics of shallow aquifers on water and nitrate transport in small agricultural catchments. Journal of Hydrology, 326(1-4): 25-42. DOI:10.1016/j.jhydrol.2005.10.040
Massa, F. et al., 2008. Territ'eau, une méthode et des outils pour améliorer la gestion des paysages agricoles en vue de préserver la qualité de l'eau. Ingénieries, n° spécial: 115-132.
Matos-Moreira, M. et al., 2017. High-resolution mapping of soil phosphorus concentration in agricultural landscapes with readily available or detailed survey data. European Journal of Soil Science, 68(3): 281-294. DOI:10.1111/ejss.12420
McDowell, R.W. et al., 2014. Contrasting the spatial management of nitrogen and phosphorus for improved water quality: Modelling studies in New Zealand and France. European Journal of Agronomy(0). DOI:http://dx.doi.org/10.1016/j.eja.2013.09.011
Mellander, P.-E. et al., 2018. Integrated climate-chemical indicators of diffuse pollution from land to water. Scientific Reports, 8(1): 944. DOI:10.1038/s41598-018-19143-1
Merot, P., 1999. The influence of hedgerow systems on the hydrology of agricultural catchments in a temperate climate. Agronomie, 19(8): 655-669. DOI:10.1051/agro:19990801
Merot, P., 2003. Le comportement des petits bassins versants ruraux dans le contexte des crues et des inondations (Small rural catchment functionning in the framework of floods and rainfall-runoff events). La Houille Blanche, 6: 74-82.
Merot, P., Aurousseau, P., Gascuel-Odoux, C., Durand, P., 2009. Innovative assessment tools to improve water quality and watershed management in farming areas. Integrated Environmental Assessment and Management, 5(1): 158-166. DOI:10.1897/ieam_2008-025.1
Merot, P., Bridet-Guillaume, F., 2006. Les bocages armoricains : repères sur l'évolution des thèmes de recherche depuis les années 1960. Natures Sciences Sociétés, 14(1): 43-49.
Merot, P., Bruneau, P., 1993. Sensitivity of bocage landscapes to surfaces run-off - application of the kirkby index. Hydrological Processes, 7(2): 167-176. DOI:10.1002/hyp.3360070207
Merot, P. et al., 2014a. Évaluation, impacts et perceptions du changement climatique dans le Grand Ouest de la France métropolitaine : le projet CLIMASTER. Cahiers de l'Agriculture, 23(2): 96-107. DOI:10.1684/agr.2014.0694
Merot, P. et al., 2014b. Assessment, impact and perception of climate change in the western part of France: The CLIMASTER project. Cahiers Agricultures, 23(2): 96-107. DOI:10.1684/agr.2014.0694
Merot, P., Crave, A., Gascuelodoux, C., Louhala, S., 1994. Effect of saturated areas on backscattering coefficient of the ers-1 synthetic-aperture radar - first results. Water Resour. Res., 30(2): 175-179. DOI:10.1029/93wr02920
Merot, P., Ezzahar, B., Walter, C., Aurousseau, P., 1995. Mapping waterlogging of soils using digital terrain models. Hydrological Processes, 9(1): 27-34. DOI:10.1002/hyp.3360090104
Merot, P., Gascuel-Odoux, C., Walter, C., Zhang, X., Molenat, J., 1999. Influence du réseau de haies des paysages bocagers sur le cheminement de l'eau de surface. Revue des Sciences de l'Eau, 12(1): 23-44.
Merot, P. et al., 2006. A method for improving the management of controversial wetland. Environ. Manage., 37(2): 258-270. DOI:10.1007/s00267-004-0391-4
Merot, P. et al., 2003. Testing a climato-topographic index for predicting wetlands distribution along an European climate gradient. Ecological Modelling, 163(1–2): 51-71. DOI:http://dx.doi.org/10.1016/S0304-3800(02)00387-3
Minaudo, C. et al., 2017. Nonlinear empirical modeling to estimate phosphorus exports using continuous records of turbidity and discharge. Water Resour. Res., 53(9): 7590-7606. DOI:10.1002/2017wr020590
Molenat, J., Davy, P., Gascuel-Odoux, C., Durand, P., 1999. Study of three subsurface hydrologic systems based on spectral and cross-spectral analysis of time series. Journal of Hydrology, 222(1-4): 152-164. DOI:10.1016/s0022-1694(99)00107-9
Molenat, J., Davy, P., Gascuel-Odoux, C., Durand, P., 2000. Spectral and cross-spectral analysis of three hydrological systems. Phys. Chem. Earth Pt B-Hydrol. Oceans Atmos., 25(4): 391-397. DOI:10.1016/s1464-1909(00)00032-0
Molenat, J., Durand, P., Gascuel-Odoux, C., Davy, P., Gruau, G., 2002. Mechanisms of nitrate transfer from soil to stream in an agricultural watershed of French Brittany. Water Air and Soil Pollution, 133(1-4): 161-183. DOI:10.1023/a:1012903626192
Molenat, J., Gascuel-Odoux, C., 2001. Role of shallow groundwater in nitrate and herbicide transport in the Kervidy agricultural catchment (Brittany, France). In: Gehrels, H.P.N.E.H.E.J.K.L.C.G., J; Webb, B.Z.W.J. (Eds.), Impact of Human Activity on Groundwater Dynamics. Iahs Publication, pp. 347-351.
Molenat, J., Gascuel-Odoux, C., 2002. Modelling flow and nitrate transport in groundwater for the prediction of water travel times and of consequences of land use evolution on water quality. Hydrological Processes, 16(2): 479-492. DOI:10.1002/hyp.328
Molénat, J., Gascuel-Odoux, C., Aquilina, L., Ruiz, L., 2013. Use of gaseous tracers (CFCs and SF6) and transit-time distribution spectrum to validate a shallow groundwater transport model. Journal of Hydrology, 480(0): 1-9. DOI:http://dx.doi.org/10.1016/j.jhydrol.2012.11.043
Molénat, J., Gascuel-Odoux, C., Davy, P., Durand, P., 2005. How to model shallow water-table depth variations: the case of the Kervidy-Naizin catchment, France. Hydrological Processes, 19(4): 901-920. DOI:10.1002/hyp.5546
Molenat, J., Gascuel-Odoux, C., Ruiz, L., Gruau, G., 2008. Role of water table dynamics on stream nitrate export and concentration. in agricultural headwater catchment (France). Journal of Hydrology, 348(3-4): 363-378. DOI:10.1016/j.jhydrol.2007.10.005
Morel, B., 2009. Transport de Carbone Organique Dissous dans un bassin versant agricole à nappe superficielle. Thèse de doctorat Thesis, Agrocampus Ouest, 208 p. pp.
Morel, B., Durand, P., Jaffrezic, A., Gruau, G., Molenat, J., 2009. Sources of dissolved organic carbon during stormflow in a headwater agricultural catchment. Hydrological Processes, 23(20): 2888-2901. DOI:10.1002/hyp.7379
Ndiaye, B., Molénat, J., Hallaire, V., Gascuel, C., Hamon, Y., 2007. Effects of agricultural practices on hydraulic properties and water movement in soils in Brittany (France). Soil and Tillage Research, 93(2): 251-263. DOI:http://dx.doi.org/10.1016/j.still.2006.04.005
Oehler, F., 2006. Mesure de la dénitrification et modélisation spatialisée des flux d'azote à l'échelle d'un petit bassin versant d'élevage, Agrocampus Ouest, 199 p. pp.
Oehler, F., Durand, P., Bordenave, P., Saadi, Z., Salmon-Monviola, J., 2009. Modelling denitrification at the catchment scale. Science of the Total Environment, 407(5): 1726-1737. DOI:10.1016/j.scitotenv.2008.10.069
Olivie-Lauquet, G. et al., 2001. Release of Trace Elements in Wetlands: Role of Seasonal Variability. Water Research, 35(4): 943-952. DOI:http://dx.doi.org/10.1016/S0043-1354(00)00328-6
Ollivier, P. et al., 2018. Natural attenuation of TiO2 nanoparticles in a fractured hard-rock. Journal of Hazardous Materials, 359: 47-55. DOI:10.1016/j.jhazmat.2018.07.035
Panettieri, M. et al., 2020. Grassland-cropland rotation cycles in crop-livestock farming systems regulate priming effect potential in soils through modulation of microbial communities, composition of soil organic matter and abiotic soil properties. Agriculture, Ecosystems & Environment, 299: 106973. DOI:https://doi.org/10.1016/j.agee.2020.106973
Pauwels, H., 1994. Natural denitrification in groundwater in the presence of pyrite: preliminary results obtained at Naizin (Brittany, France). Mineralogical Magazine, 58A: 696-697.
Pauwels, H., Ayraud-Vergnaud, V., Aquilina, L., Molénat, J., 2010. The fate of nitrogen and sulfur in hard-rock aquifers as shown by sulfate-isotope tracing. Applied Geochemistry, 25(1): 105-115. DOI:http://dx.doi.org/10.1016/j.apgeochem.2009.11.001
Payraudeau, S., van der Werf, H.M.G., Vertes, F., 2007. Analysis of the uncertainty associated with the estimation of nitrogen losses from farming systems. Agricultural Systems, 94(2): 416-430. DOI:10.1016/j.agsy.2006.11.014
Pedron, A., 2009. Développement d'algorithmes d'imagerie et de reconstruction sur architectures à unités de traitements parallèles pour des applications en contrôle non destructif, Université Paris Sud - Paris XI, 160 p. pp.
Pédrot, M., 2009. Colloïdes et compositions élémentaires des solutions de sols, Université Rennes 1.
Pédrot, M., Dia, A., Davranche, M., 2009. Double pH control on humic substance-borne trace elements distribution in soil waters as inferred from ultrafiltration. Journal of Colloid and Interface Science, 339(2): 390-403. DOI:http://dx.doi.org/10.1016/j.jcis.2009.07.046
Pédrot, M., Dia, A., Davranche, M., 2010. Dynamic structure of humic substances: Rare earth elements as a fingerprint. Journal of Colloid and Interface Science, 345(2): 206-213. DOI:http://dx.doi.org/10.1016/j.jcis.2010.01.069
Pédrot, M. et al., 2008. Insights into colloid-mediated trace element release at the soil/water interface. Journal of Colloid and Interface Science, 325(1): 187-197. DOI:http://dx.doi.org/10.1016/j.jcis.2008.05.019
Pedrot, M., Dia, A., Davranche, M., Gruau, G., 2015. Upper soil horizons control the rare earth element patterns in shallow groundwater. Geoderma, 239: 84-96. DOI:10.1016/j.geoderma2014.09.023
Pierson-Wickmann, A.-C. et al., 2009a. High chemical weathering rates in first-order granitic catchments induced by agricultural stress. Chemical Geology, 265(3-4): 369-380. DOI:10.1016/j.chemgeo.2009.04.014
Pierson-Wickmann, A.-C., Aquilina, L., Weyer, C., Molénat, J., Lischeid, G., 2009b. Acidification processes and soil leaching influenced by agricultural practices revealed by strontium isotopic ratios. Geochimica Et Cosmochimica Acta, 73(16): 4688-4704. DOI:http://dx.doi.org/10.1016/j.gca.2009.05.051
Pierson-Wickmann, A.-C. et al., 2021. Monitoring the Organic Matter Quality Highlights the Ways in Which Organic Matter Is Removed from Wetland Soil. Geosciences, 11(3): 134.
Pierson-Wickmann, A.-C. et al., 2011. Development of a combined isotopic and mass-balance approach to determine dissolved organic carbon sources in eutrophic reservoirs. Chemosphere, 83(3): 356-366. DOI:http://dx.doi.org/10.1016/j.chemosphere.2010.12.014
Pourret, O., 2006. Impact de la matière organique sur le comportement des terres rares en solution: étude expérimentale et modélisation, Université Rennes 1, 184 p. pp.
Pourret, O., Davranche, M., Gruau, G., Dia, A., 2007a. Organic complexation of rare earth elements in natural waters: Evaluating model calculations from ultrafiltration data. Geochimica Et Cosmochimica Acta, 71(11): 2718-2735. DOI:http://dx.doi.org/10.1016/j.gca.2007.04.001
Pourret, O. et al., 2007b. Organo-colloidal control on major- and trace-element partitioning in shallow groundwaters: Confronting ultrafiltration and modelling. Applied Geochemistry, 22(8): 1568-1582. DOI:http://dx.doi.org/10.1016/j.apgeochem.2007.03.022
Pourret, O., Gruau, G., Dia, A., Davranche, M., Molenat, J., 2010. Colloidal Control on the Distribution of Rare Earth Elements in Shallow Groundwaters. Aquat. Geochem., 16(1): 31-59. DOI:10.1007/s10498-009-9069-0
Ratié, G. et al., 2019. Iron speciation at the riverbank surface in wetland and potential impact on the mobility of trace metals. Science of The Total Environment, 651: 443-455. DOI:https://doi.org/10.1016/j.scitotenv.2018.09.143
Roussel, J.-M., Gascuel-Odoux, C., Grimaldi, C., Pascal, M., Baglinière, J.-L., 2012. Histoire des pressions anciennes et récentes sur les milieux aquatiques en Bretagne (Historical analysis of human activities and their effects on freshwaters in Brittany). Innovations Agronomiques, 23: 95-105.
Rouxel, M. et al., 2011. Seasonal and spatial variation in groundwater quality along the hillslope of an agricultural research catchment (Western France). Hydrological Processes, 25(6): 831-841. DOI:10.1002/hyp.7862
Rouxel, M. et al., 2012. Experimental Determination of Hydrodynamic Properties of Weathered Granite. Vadose Zone Journal, 11(3). DOI:10.2136/vzj2011.0076
Ruiz, L. et al., 2002a. Effect on nitrate concentration in stream water of agricultural practices in small catchments in Brittany : I. Annual nitrogen budgets. Hydrology and Earth System Sciences, 6(3): 497-505.
Ruiz, L. et al., 2002b. Effect on nitrate concentration in stream water of agricultural practices in small catchments in Brittany : II. Temporal variations and mixing processes. Hydrology and Earth System Sciences, 6(3): 507-513.
Salmon-Monviola, J. et al., 2011. Simulating the effect of technical and environmental constraints on the spatio-temporal distribution of herbicide applications and stream losses. Agriculture, Ecosystems & Environment, 140(3–4): 382-394. DOI:http://dx.doi.org/10.1016/j.agee.2010.12.022
Salmon-Monviola, J. et al., 2013. Effect of climate change and increased atmospheric CO2 on hydrological and nitrogen cycling in an intensive agricultural headwater catchment in western France. Clim. Change, 120(1-2): 433-447. DOI:10.1007/s10584-013-0828-y
Simon, N. et al., 2022. Combining passive and active distributed temperature sensing measurements to locate and quantify groundwater discharge variability into a headwater stream. Hydrol. Earth Syst. Sci., 26(5): 1459-1479. DOI:10.5194/hess-26-1459-2022
Sorel, L., 2008. Paysages virtuels et analyse de scénarios pour évaluer les impacts environnementaux des systèmes de production agricole. Thèse de doctorat Thesis, Agrocampus Ouest, 160 p. + annexes pp.
Sorel, L., Viaud, V., Durand, P., Walter, C., 2010. Modeling spatio-temporal crop allocation patterns by a stochastic decision tree method, considering agronomic driving factors. Agricultural Systems, 103(9): 647-655. DOI:10.1016/j.agsy.2010.08.003
Soulier, A., Jardé, E., Le Bot, B., Carrera, L., Jaffrézic, A., 2016. Résidus médicamenteux vétérinaires : quelles molécules rechercher dans les eaux superficielles en contexte d’élevage intensif ? TSM(11): 69-92.
Strohmenger, L. et al., 2020. Multitemporal Relationships Between the Hydroclimate and Exports of Carbon, Nitrogen, and Phosphorus in a Small Agricultural Watershed. Water Resour. Res., 56(7): e2019WR026323. DOI:10.1029/2019wr026323
Strohmenger, L., Fovet, O., Hrachowitz, M., Salmon-Monviola, J., Gascuel-Odoux, C., 2021. Is a simple model based on two mixing reservoirs able to reproduce the intra-annual dynamics of DOC and NO3 stream concentrations in an agricultural headwater catchment? Science of The Total Environment, 794: 148715. DOI:https://doi.org/10.1016/j.scitotenv.2021.148715
Tete, E., Viaud, V., Walter, C., 2015. Organic carbon and nitrogen mineralization in a poorly-drained mineral soil under transient waterlogged conditions: an incubation experiment. European Journal of Soil Science, 66(3): 427-437. DOI:10.1111/ejss.12234
Tortrat, F., Aurousseau, P., Squividant, H., Gascuel-Odoux, C., Cordier, M.O., 2003. Modèle numérique d'altitude (MNA) et spatialisation des transferts de surface : utilisation de structures d'arbres reliant les exutoires de parcelles et leurs surfaces contributives. Bulletin SFPT, 172: 128-136.
Trolard, F. et al., 1997. Identification of a green rust mineral in a reductomorphic soil by Mossbauer and Raman spectroscopies. Geochimica Et Cosmochimica Acta, 61(5): 1107-1111. DOI:10.1016/s0016-7037(96)00381-x
Viaud, V., 2004. Organisation spatiale des paysages bocagers et flux d'eau et de nutriments. Approche empirique et modélisations, Agrocampus - Ecole nationale supérieure d'agronomie de rennes, 255 p. pp.
Viaud, V., Durand, P., Merot, P., Sauboua, E., Saadi, Z., 2005. Modeling the impact of the spatial structure of a hedge network on the hydrology of a small catchment in a temperate climate. Agricultural Water Management, 74(2): 135-163. DOI:http://dx.doi.org/10.1016/j.agwat.2004.11.010
Viaud, V., Merot, P., Baudry, J., 2004. Hydrochemical Buffer Assessment in Agricultural Landscapes: From Local to Catchment Scale. Environ. Manage., 34(4): 559-573. DOI:10.1007/s00267-004-0271-y
Viaud, V. et al., 2018. Landscape-scale analysis of cropping system effects on soil quality in a context of crop-livestock farming. Agriculture, Ecosystems & Environment, 265: 166-177. DOI:https://doi.org/10.1016/j.agee.2018.06.018
Vongvixay, A., 2012. Mesure et analyse de la dynamique temporelle des flux solides dans les petits bassins versants. Thèse de l'universtié Thesis, INSA Rennes, 186 p. pp.
Vongvixay, A. et al., 2018. Contrasting suspended sediment export in two small agricultural catchments: Cross-influence of hydrological behaviour and landscape degradation or stream bank management. Land Degradation & Development, 29(5): 1385-1396. DOI:doi:10.1002/ldr.2940
Wade, A.J. et al., 2002. A nitrogen model for European catchments: INCA, new model structure and equations. Hydrology and Earth System Sciences, 6(3): 559-582.
Walter, C., Merot, P., Layer, B., Dutin, G., 2003. The effect of hedgerows on soil organic carbon storage in hillslopes. Soil Use and Management, 19(3): 201-207. DOI:10.1111/j.1475-2743.2003.tb00305.x
Weyer, C., Lischeid, G., Aquilina, L., Pierson-Wickmann, A.C., Martin, C., 2008. Mineralogical sources of the buffer capacity in a granite catchment determined by strontium isotopes. Applied Geochemistry, 23(10): 2888-2905. DOI:10.1016/j.apgeochem.2008.04.006
Yeghicheyan, D. et al., 2001. A Compilation of Silicon and Thirty One Trace Elements Measured in the Natural River Water Reference Material SLRS-4 (NRC-CNRC). Geostandards Newsletter, 25(2-3): 465-474. DOI:10.1111/j.1751-908X.2001.tb00617.x