A comprehensive dataset on nitrate, Nitrite and dissolved organic carbon leaching losses from a 4-year Lysimeter study.

This article presents a dataset on nitrate, nitrite and dissolved organic carbon (DOC) losses measured for 4 years using lysimeters at the EFELE long-term experimental site (Le Rheu, France). This ongoing long-term study was designed to provide information on effects of organic waste product (OWP) application and soil tillage on crop production, soil properties, biodiversity, greenhouse gas emissions and water quality. Forty wick-fiber lysimeters were installed at depths of 40 and 90 cm to document effects of organic and/or mineral fertilization, vegetation cover and weather conditions on dynamics of nitrate, nitrite and DOC concentrations of water collected during the drainage season (winter). These data help analyze the effects of winter plant cover (wheat vs. mustard catch crop) on these dynamics and fill a knowledge gap on effects of organic waste product supply on DOC losses. These dynamic data over several years are also of great interest for calibrating and evaluating models (e.g. STICS, APSIM, CERES).

Veterinary pharmaceutical residues in water resources and tap water in an intensive husbandry area in France.

In intensive livestock areas, veterinary pharmaceutical residues (VPRs) can occur in water resources, but also in tap water because treatment processes are not designed to remove these contaminants. The main objective of this study is to assess the occurrence of VPRs in water resources and tap waters in Brittany. As several identical compounds are used in both veterinary and human medicine, a toolbox (stanols and pharmaceuticals) is used to help determine the origin of contamination in the case of mixed-use molecules. Water resources samples were collected from 25 sites (23 surface waters and two groundwaters) used for tap water production and located in watersheds considered as sensitive due to intensive husbandry activities. Samples were also taken at 23 corresponding tap water sites. A list of 38 VPRs of interest was analyzed. In water resources, at least one VPR was quantified in 32% of the samples. 17 different VPRs were quantified, including antibiotics, antiparasitic drugs and anti-inflammatory drugs. Concentration levels ranged between 5 ng/L and 2946 ng/L. Mixed-use pharmaceuticals were quantified in twelve samples of water resources and among these samples nine had a mixed overall fecal contamination. In the context of this large-scale study, it appeared difficult to determine precisely the factors impacting the occurrence of VPRs. VPRs were quantified in 20% of the tap water samples. Twelve VPRs were quantified, including ten compounds exclusively used in veterinary medicine and two mixed-use compounds. Concentration levels are inferior to 40 ng/L for all compounds, with the exception of the antibiotic florfenicol which was quantified at 159 ng/L and 211 ng/L. The population of Brittany may therefore be exposed to these contaminants through tap water. These observations should be put into perspective with the detection frequencies per compound which are all below 10% in both water resources and tap water.

Veterinary pharmaceutical residues from natural water to tap water: Sales, occurrence and fate.

Veterinary pharmaceuticals (VPs) increasingly used in animal husbandry have led to their presence in aquatic environments -surface water (SW) or groundwater (GW) - and even in tap water. This review focuses on studies from 2007 to 2017. Sixty-eight different veterinary pharmaceutical residues (VPRs) have been quantified worldwide in natural waters at concentrations ranging from nanograms per liter (ng L-1) to several micrograms per liter (µg L-1). An extensive up-to-date on sales and tonnages of VPs worldwide has been performed. Tetracyclines (TCs) antibiotics are the most sold veterinary pharmaceuticals worldwide. An overview of VPRs degradation pathways in natural waters is provided. VPRs can be degraded or transformed by biodegradation, hydrolysis or photolysis. Photo-degradation appears to be the major degradation pathway in SW. This review then reports occurrences of VPRs found in tap water, and presents data on VPRs removal in drinking water treatment plants (DWTPs) at each step of the process. VPRs have been quantified in tap water at ng L-1 concentration levels in four studies of the eleven studies dealing with VPRs occurrence in tap water. Overall removals of VPRs in DWTPs generally exceed 90% and advanced treatment processes (oxidation processes, adsorption on activated carbon, membrane filtration) greatly contribute to these removals. However, studies performed on full-scale DWTPs are scarce. A large majority of fate studies in DWTPs have been conducted under laboratory at environmentally irrelevant conditions (high concentration of VPRs (mg L-1), use of deionized water instead of natural water, high concentration of oxidant, high contact time etc.). Also, studies on VPRs occurrence and fate in tap water focus on antibiotics. There is a scientific gap on the occurrence and fate of antiparatic drugs in tap waters.

Groundwater control of biogeochemical processes causing phosphorus release from riparian wetlands.

Because of the high sorption affinity of phosphorus (P) for the soil solid phase, mitigation options to reduce diffuse P transfer usually focus on trapping particulate P delivered via surface flow paths. Therefore, placing riparian buffers between croplands and watercourses has been promoted worldwide, sometimes in wetland areas. To investigate the risk of P-accumulating riparian wetlands (RWs) releasing dissolved P into streams, we monitored molybdate-reactive P (MRP) in the soil pore water of two RWs in an agricultural watershed. Two main mechanisms released MRP under the control of groundwater dynamics. First, soil rewetting after the dry summer period was associated with the presence of a pool of mobile P, limited in size. Its mobilization started under water saturated conditions caused by a rise in groundwater. Second, anoxic conditions at the end of winter caused reductive dissolution of Fe (hydr)oxides along with a release of MRP. Comparison of sites revealed that the first MRP release occurred only in RWs with P-enriched soils, whereas the second was observed even in RWs with low soil P status. Seasonal variations in stream MRP concentrations were similar to concentrations in RW soils. Hence, RWs can act as a key component of the P transfer continuum in agricultural landscapes by converting particulate P from croplands into MRP transferred to streams.

Microbial and chemical markers: runoff transfer in animal manure-amended soils.

Fecal contamination of water resources is evaluated by the enumeration of the fecal coliforms and Enterococci. However, the enumeration of these indicators does not allow us to differentiate between the sources of fecal contamination. Therefore, it is important to use alternative indicators of fecal contamination to identify livestock contamination in surface waters. The concentration of fecal indicators (, enteroccoci, and F-specific bacteriophages), microbiological markers (Rum-2-bac, Pig-2-bac, and ), and chemical fingerprints (sterols and stanols and other chemical compounds analyzed by 3D-fluorescence excitation-matrix spectroscopy) were determined in runoff waters generated by an artificial rainfall simulator. Three replicate plot experiments were conducted with swine slurry and cattle manure at agronomic nitrogen application rates. Low amounts of bacterial indicators (1.9-4.7%) are released in runoff water from swine-slurry-amended soils, whereas greater amounts (1.1-28.3%) of these indicators are released in runoff water from cattle-manure-amended soils. Microbial and chemical markers from animal manure were transferred to runoff water, allowing discrimination between swine and cattle fecal contamination in the environment via runoff after manure spreading. Host-specific bacterial and chemical markers were quantified for the first time in runoff waters samples after the experimental spreading of swine slurry or cattle manure.

Discrimination of farm waste contamination by fluorescence spectroscopy coupled with multivariate analysis during a biodegradation study.

The persistence of potential tracers of dissolved organic matter (DOM) generated from farm waste-amended soil was investigated by fluorescence spectroscopy coupled with classification and regression tree (CART) and principal component analysis (PCA) during a short-term (8 days) to midterm (60 days) biodegradation study. Pig manure (PM), cow manure (CM), wheat straw (WS), and soil alone (SA) treatment inputs were used. Waste amendments were potential sources of higher DOM concentrations. PCA revealed the DOM quality differences between farm wastes and soil alone as well as a significant shift observed from the biochemical to the geochemical fluorescent fraction in SA and PM treatments. The tryptophan:Humic-Like ratio and tryptophan zone were the potential discriminators of recent and midterm pollution by farm wastes. Integral intensities of the Fulvic-Like zone and region III discriminated the PM from CM and WS during the 60 days. CART analysis showed 90 and 100% potential for farm wastes discrimination from soil during P1 and P2, respectively. The prediction successes were 72 and 57% for PM from other wastes and 60 and 100% for WS during both periods. Fluorescence spectroscopy in combination with CART analysis can be a nondestructive innovative method for monitoring susceptible farm waste contamination.

Tracing and quantifying sources of fatty acids and steroids in amended cultivated soils.

Soluble organic fractions from soils of two agricultural sites from Brittany (France) have been analyzed to (i) identify the source of polar compounds in soils and (ii) evaluate the impact of organic fertilization and crop type on the distribution and concentration of polar compounds in soils. The main sources of polar compounds in soils are higher plants; they represent >70% of the polar compounds from the experimental sites and mainly originate from crop residues and animal manure. Crop type and animal manure application significantly increase the polar compound concentrations in soils. Among polar compounds, fatty acids cannot be used as specific markers because their distributions in soils whatever the crop type or organic fertilization type are the same. On the other hand, analysis of steroids provides interesting information. Cow and poultry manure applications increase only the concentration of steroids. Pig slurry fertilization modifies both the concentration and distribution of steroids. The identified pig slurry steroid fingerprint can persist in the soil for 9 years after the slurry application has been stopped. Those compounds are then robust markers to detect pig slurry contribution in soils.

Delta13C values of grasses as a novel indicator of pollution by fossil-fuel-derived greenhouse gas CO2 in urban areas.

A novel fossil fuel pollution indicator based on the 13C/12C isotopic composition of plants has been designed. This bioindicator is a promising tool for future mapping of the sequestration of fossil fuel CO2 into urban vegetation. Theoretically, plants growing in fossil-fuel-CO2-contaminated areas, such as major cities, industrial centers, and highway borders, should assimilate a mixture of global atmospheric CO2 of delta13C value of -8.02 per thousand and of fossil fuel CO2 of average delta13C value of -27.28 per thousand. This isotopic difference should, thus, be recorded in plant carbon. Indeed, this study reveals that grasses growing near a major highway in Paris, France, have strikingly depleted delta13C values, averaging at -35.08 per thousand, versus rural grasses that show an average delta13C value of -30.59 per thousand. A simple mixing model was used to calculate the contributions of fossil-fuel-derived CO2 to the plant tissue. Calculation based on contaminated and noncontaminated isotopic end members shows that urban grasses assimilate up to 29.1% of fossil-fuel-CO2-derived carbon in their tissues. The 13C isotopic composition of grasses thus represents a promising new tool for the study of the impact of fossil fuel CO2 in major cities.