Unveiling the impact of human urine fertilization on soil bacterial communities: A path toward sustainable fertilization

Using human urine as a crop fertilizer has sparked interest due to its potential benefits, but its application requires an understanding of how urine can affect soil functions and microbial communities. This study aims at elucidating the response of soil bacterial communities to fertilization with human urine. To this end, a spinach crop was fertilized with 2 different doses of a source-separated and stored human urine (170 kg N ha−1 + 8.5 kg P ha−1 and 510 kg N ha−1 + 25.5 kg P ha−1) and compared with a synthetic fertilizer treatment (170 kg N ha−1 + 8.5 kg P ha−1) and a water treatment without fertilization. The experiment was conducted in four soil tanks in greenhouse conditions, according to a randomized block scheme. We assessed urine and soil bacterial composition at the beginning and the end of the experiment that we compared to soil and plant properties to understand the drivers in bacterial composition changes. After 12 months of storage, urine had a depleted microbiome but still contained few common strains of urine or faeces. Overall, soil bacterial communities were resistant to urine fertilization with only 3 % of the taxa impacted. However, urine fertilization increased the relative abundance of nitrifying and denitrifying groups compared to the synthetic fertilizer implying that more N2O and NO could be emitted when fertilizing with urine. The urine's high salt concentration had little discernible effect on the bacterial community. In a broader context, this experiment provides evidence that one-year-stored urine can be applied to a plant-soil system without negatively impacting soil bacterial communities in the short term

Methodology to evaluate dripper sensitivity to clogging due to solid particles: an assessment

Emitter clogging is a major problem in microirrigation systems, which may result from the isolated or combined efects of physical, chemical, and biological agents. Clogging caused by suspended solid particles is the most common plugging form of emitters. Water quality and emitter geometry are key aspects in clogging processes. Any suitable test procedure to assess the sensitivity of drippers to clogging should take into account the predominant factors that infuence clogging and must reproduce the feld conditions. Tis research set out to assess the performance and suitability of a laboratory clogging test procedure in order to validate a methodology and to provide scientifc results that may support the standardization of a clogging test method. Te evaluated methodology has been used by the IRSTEA laboratory since 1974 (Platform of Research and experiment on Science and Technology for Irrigation - PReSTI, formerly LERMI) and its contents are currently being discussed by the ISO TC23/SC18 committee. Te aim is to defne a standardized testing protocol to evaluate the sensitivity of emitters to clogging due to solid particles. Replications analyzing the clogging resistance of four models of emitting pipes were carried out in a laboratory.Te clogging test procedure enabled an accurate assessment of the combinations of concentration and size of particles that caused clogging in each model of dripper. However, a signifcant variability in degree of clogging was identifed when the results of replications for each model of dripper were compared. Several requirements, concerns, and improvements related to the clogging test protocol were discussed.2018FUNDAÇÃO DE AMPARO À PESQUISA DO ESTADO DE SÃO PAULO - FAPESP2015/19630-

Réutilisation des eaux usées en irrigation

International audiencePartout sur le pourtour méditerranéen, mais aussi en Europe continentale, les besoins en eau évoluent sous les effets du changement climatique : les baisses des précipitations et les hausses des températures imposent de repenser les modes de gestion de l’eau, tant en quantité qu’en qualité, pour l’ensemble des activités humaines (agriculture, eau potable, industrie) et non- humaines (débit et qualité des cours d’eau). Les eaux usées par les activités humaines sont aujourd’hui considérées comme des ressources souvent sous-exploitées ou mal-exploitées, que ce soit sous l’angle quantitatif (réutiliser mieux l’eau) aussi bien que qualitatif (réutiliser davantage les éléments fertilisants contenus dans celle-ci et limiter les rejets directs dans les milieux). L’objectif de la présentation est de présenter les enjeux positifs ou négatifs de la réutilisation des enjeux et les avancés de nos recherches à la plateforme de recherche Murviel-Lès-Montpelli

Water reuse irrigation for vineyard in Occitanie region, France

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Drip-irrigation and health issues of water reuse in agriculture

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Les défis de l’agriculture urbaine et périurbaine

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Water Reuse in Algerian Oasis Region: Institutional Management Bottlenecks and Demonstration of Operational Feasibility

International audienceIn the Algerian Sahara, non-renewable groundwater resources estimated at 5 billion m3 thus constitute the indispensable support for irrigation. In the Berriane region in the north of Ghardaïa region (center of Algerian Sahara), an agricultural perimeter called Oued El Bir (300 ha in total) was officially created in 2013 downstream a wastewater treatment plant. A “frontier settlement” that proves the high value placed on this resource.As part of Massire project financed by IFAD (2018-2024), the objective of our study was to analyze the water reuse practices in this Berriane arid region, i.e. to study the importance of the institutional management of the treated wastewater reuse on the one hand. And on the other hand to show that the malfunctioning of the wastewater treatment plants can lead to many side effects such as the infiltration of raw sewage into the groundwater, illicit untreated wastewater irrigation and a slowdown in the development of the agricultural perimeter. Our research methodology is founded, firstly, on interviews with the local stakeholders (about 20 surveys with farmers and local institutions) and, secondly, on isotopic, chemical and biological water analyses that will be carried out soon to validate the hypothesis of infiltration of wastewater into the aquifer. In addition, to address the institutional opposition and issues relating to the technical sustainability of water reuse in the region, we implemented a water reuse demonstrator. The choice of location and equipment was determined in concertation with local stakeholders. The decentralized treatment process is based on a septic tank and a fixed bacterial filter (Advanced Enviro Septic) with 10 m3/day capacity. The treated wastewaters are used to irrigate a 1 ha surface of the new oasis area. As part of our study, we are investigating the sanitary and agronomic safety of this new treatment process for water reuse in the arid context