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An indicator to evaluate the proportion of exogenous organic matter (EOM) remaining in soils over the long-term after application has been developed. A database was constructed with analytical data corresponding to 83 EOMs, including sludges, composts, animal wastes, mulches, plant materials and fertilizers. The data included results of proximal analysis (soluble, SOL, hemicellulose-, HEM, cellulose-, CEL, and lignin-like, LIC, fractions, in g kg-1 total organic matter) and of carbon (C) mineralization during long-term incubations under laboratory conditions (in g kg-1 exogenous organic C, EOC). The potential residual organic C after EOM application to soil was assessed from the extrapolation of the incubation results. Then, partial least square regression was used to relate EOM characteristics to the proportion of potentially residual organic C previously determined from the incubations. The biochemical fractions of EOM were not predictive enough to develop the indicator. The proportion of organic C mineralized during 3 days of incubation (C3d) was cumulated and appeared to be the most predictive variable of residual organic C. The proposed indicator of residual organic carbon in soils (expressed as g EOC kg-1) was IROC = 445 + 0.5 SOL - 0.2 CEL + 0.7 LIC - 2.3 C3d. The indicator was calculated for the main types of EOM applied to soils. When compared with the few field data of residual C measured in long-term field experiments, the values provided by the indicator seemed to be over-estimated (i.e. EOC degradation could be faster under field conditions than during laboratory incubations)

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processes, which are modelled as the product of a potential rate with three dimensionless factors 10 related to soil water content, nitrogen content and temperature. These equations involve a total 11 set of 15 parameters, four of which are site-specific and should be measured on site, while the 12 other 11 are considered global, i.e. invariant over time and space. We first gathered prior informa- scales.

One alternative to mineral fertilization is to use organic fertilizers. Our aim was to compare the impacts of 7-year applications of composted pig manure and ammonium nitrate on the structure and activity of the denitrifying community. Mineralization and organization of N, denitrification rates and N2O/N2 ratio were also investigated. Fourteen months after the last application, the potential denitrifying activity (+319%), N mineralization (+110%) and organization (+112%) were higher under pig compost than under ammonium nitrate fertilization. On the other hand, the N2O/(N2O+N2) ratio was lower (P<0.05, n=5) under organic fertilization. These effects of organic fertilization were in accordance with its higher total carbon content and microbial biomass. Fingerprints and clone library analyses showed that the structure of the denitrifying community was affected by the fertilization regime. Our results reveal that organic or mineral fertilizer applications could affect both structure and activity of the denitrifying community, with a possible influence on in situ N2O fluxes. These effects of the fertilization regime persisted for at least 14 months after the last application.

Zwitterionic, cationic, and anionic per- and polyfluoroalkyl substances (PFAS) are increasingly reported in terrestrial and aquatic environments, but their inputs to agricultural lands are not fully understood. Here, we characterized PFAS in 47 organic waste products (OWP) applied in agricultural fields of France, including historical and recent materials. Overall, 160 PFAS from 42 classes were detected from target screening and homologue-based nontarget screening. Target PFAS were low in agriculture-derived wastes such as pig slurry, poultry manure, or dairy cattle manure (median ∑46PFAS: 0.66 μg/kg dry matter). Higher PFAS levels were reported in urban and industrial wastes, paper mill sludge, sewage sludge, or residual household waste composts (median ∑46PFAS: 220 μg/kg). Historical municipal biosolids and composts (1976–1998) were dominated by perfluorooctanesulfonate (PFOS), N-ethyl perfluorooctanesulfonamido acetic acid (EtFOSAA), and cationic and zwitterionic electrochemical fluorination precursors to PFOS. Contemporaneous urban OWP (2009–2017) were rather dominated by zwitterionic fluorotelomers, which represented on average 55% of ∑160PFAS (max: 97%). The fluorotelomer sulfonamidopropyl betaines (X:2 FTSA-PrB, median: 110 μg/kg, max: 1300 μg/kg) were the emerging class with the highest occurrence and prevalence in contemporary urban OWP. They were also detected as early as 1985. The study informs for the first time that urban sludges and composts can be a significant repository of zwitterionic and cationic PFAS.

Measuring customers benefits of click and collectPurpose -Click and collect (or grocery pickup) represents a growing part of the channel strategy of traditional off-line retailers. The objective is to understand how customers develop their perceptions towards this new channel. In other words, what are the key factors explaining the long-term value creation for each "click and collect" system depending on consumers' profiles?Design/Methodology/Approach -Based on a quantitative survey of 479 respondents, this research uses confirmatory analyses based on the PLS path modeling.Findings -Based on the structural model, the customers' relations, the website, the pickup station are the most important factors creating value for customers whatever the Internet grocery shopping model. The global conceptual model has been implemented under many variations to test the age effect and the kind of click and collect model. It is made evidence that customers' benefits vary regarding the kind of click and collect model and the age of customers. Research limitations/implications-This research allows a better understanding of the performance of the click and collect system by looking at the key factors that maximize the customers' value and those that decrease it. Results show precisely variations of those factors according to the customer's profile and the click and collect model. Originality/value -This quantitative paper studies customer behaviors towards their usual retailer and their relationship with him. To do so, segmented approaches of the causal model are retained to provide specific recommendations.The model is validated because statistical indicators exceed the recommended threshold (Chin, 1998;Fornell and Larcker, 1981;Tenenhaus et al., 2005). The causal model is expressed as follows (Table 8).-Insert Table 8 about here- Key factors of click and collectAs shown in Table 8, it appears that:Re-purchases = 0.234 relation + 0.207 website + 0.201 pickup station + 0.153 service and marketing policy + 0.103 orders + 0.016 functional benefitThe model shows the created value meaning the key success factors of click and collect, in order of importance:1) The customers' relation forms 23.4% of customer value (related to relational benefit);2) The website explains 20.7% of the customer perceived value (related to experiential benefit);3) The pickup station contributes to 20.1% of the customer perceived value (related to experiential benefit);4) The service and the marketing policy explain 15.3% of the created value (related to experiential benefit);5) The attributes related to orders contribute to 10.3% of created value (related to experiential benefit);6) The functional benefit explains 1.6% of created value.

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