This work evaluates the release of phosphorus contained in the digestate from the anaerobic digestion of pig manure, through an acidification process. The objective of this acidification is to increase the amount of phosphorus available in the digestate liquid fraction and, subsequently, recover this element by chemical precipitation in the form of struvite or calcium phosphate. Two digestate samples (one fresh and one old) were studied and treated by adding various amounts of sulphuric acid to the different digestate fractions (raw digestate, solid fraction and liquid fraction). For the raw digestate, phosphorus releases higher than 95% were obtained for pH 4.0. In the last part of the experiment, the influence of acid pre-treatment on the reaction yield of phosphorus precipitation, in the form of struvite or calcium phosphate, was determined. Improvements in reaction yield were obtained up to 15% for struvite and 80% for calcium phosphate, increasing also in 7.5 times the amount of phosphorus available in the digestate liquid fraction, for both cases.
", "keywords": ["Biofertiliser", "FEASIBILITY", "NUTRIENT RECOVERY", "PH", "Struvite", "Swine", "SWINE WASTE-WATER", "0211 other engineering and technologies", "02 engineering and technology", "7. Clean energy", "01 natural sciences", "CALCIUM", "Acidification", "ANAEROBIC-DIGESTION", "Environmental Chemistry", "PHOSPHORUS REMOVAL", "Animals", "Chemical Precipitation", "Toxicology and Mutagenesis", "Anaerobiosis", "Organic waste", "SLUDGE", "0105 earth and related environmental sciences", "Phosphorus", "General Medicine", "Pollution", "6. Clean water", "Manure", "Nutrient recovery", "Health", "Earth and Environmental Sciences", "Release", "PRECIPITATION", "Waste and Biomass Management & Valorization", "CRYSTALLIZATION"]}, "links": [{"href": "https://link.springer.com/content/pdf/10.1007/s11356-020-10918-6.pdf"}, {"href": "https://doi.org/10.1007/s11356-020-10918-6"}, {"rel": "related", "href": "https://repository.soilwise-he.eu/cat/collections/metadata:main/items/Environmental%20Science%20and%20Pollution%20Research", "name": "related record", "description": "related record", "type": "application/json"}, {"rel": "self", "type": "application/geo+json", "title": "10.1007/s11356-020-10918-6", "name": "item", "description": "10.1007/s11356-020-10918-6", "href": "https://repository.soilwise-he.eu/cat/collections/metadata:main/items/10.1007/s11356-020-10918-6"}, {"rel": "collection", "type": "application/json", "title": "Collection", "name": "collection", "description": "Collection", "href": "https://repository.soilwise-he.eu/cat/collections/metadata:main"}], "time": {"date": "2020-10-03T00:00:00Z"}}, {"id": "10.1371/journal.pone.0020105", "type": "Feature", "geometry": null, "properties": {"license": "Open Access", "updated": "2026-04-04T16:19:49Z", "type": "Journal Article", "created": "2011-06-17", "title": "Global Change Could Amplify Fire Effects On Soil Greenhouse Gas Emissions", "description": "Open AccessBackground Little is known about the combined impacts of global environmental changes and ecological disturbances on ecosystem functioning, even though such combined impacts might play critical roles in shaping ecosystem processes that can in turn feed back to climate change, such as soil emissions of greenhouse gases. Methodology/Principal Findings We took advantage of an accidental, low-severity wildfire that burned part of a long-term global change experiment to investigate the interactive effects of a fire disturbance and increases in CO2 concentration, precipitation and nitrogen supply on soil nitrous oxide (N2O) emissions in a grassland ecosystem. We examined the responses of soil N2O emissions, as well as the responses of the two main microbial processes contributing to soil N2O production \u2013 nitrification and denitrification \u2013 and of their main drivers. We show that the fire disturbance greatly increased soil N2O emissions over a three-year period, and that elevated CO2 and enhanced nitrogen supply amplified fire effects on soil N2O emissions: emissions increased by a factor of two with fire alone and by a factor of six under the combined influence of fire, elevated CO2 and nitrogen. We also provide evidence that this response was caused by increased microbial denitrification, resulting from increased soil moisture and soil carbon and nitrogen availability in the burned and fertilized plots. Conclusions/Significance Our results indicate that the combined effects of fire and global environmental changes can exceed their effects in isolation, thereby creating unexpected feedbacks to soil greenhouse gas emissions. These findings highlight the need to further explore the impacts of ecological disturbances on ecosystem functioning in the context of global change if we wish to be able to model future soil greenhouse gas emissions with greater confidence.", "keywords": ["Greenhouse Effect", "effet de serre", "sol", "Internationality", "Time Factors", "550", "Nitrogen", "QH301 Biology", "Science", "Nitrous Oxide", "incendie", "Fires", "12. Responsible consumption", "Soil", "dioxyde de carbone", "11. Sustainability", "Chemical Precipitation", "Soil Microbiology", "azote", "2. Zero hunger", "Q", "R", "04 agricultural and veterinary sciences", "Carbon Dioxide", "15. Life on land", "\u00e9mission", "[SDE.BE] Environmental Sciences/Biodiversity and Ecology", "pr\u00e9cipitation atmosph\u00e9rique", "13. Climate action", "Denitrification", "Medicine", "0401 agriculture", " forestry", " and fisheries", "[SDE.BE]Environmental Sciences/Biodiversity and Ecology", "GE Environmental Sciences", "Research Article"]}, "links": [{"href": "https://hal.science/halsde-00723483/file/2011_Niboyet_Plosone_1.pdf"}, {"href": "https://openknowledge.nau.edu/id/eprint/1706/7/Niboyet_A_etal_2011_Global_change_amplify_fire%281%29.pdf"}, {"href": "https://doi.org/10.1371/journal.pone.0020105"}, {"rel": "related", "href": "https://repository.soilwise-he.eu/cat/collections/metadata:main/items/PLoS%20ONE", "name": "related record", "description": "related record", "type": "application/json"}, {"rel": "self", "type": "application/geo+json", "title": "10.1371/journal.pone.0020105", "name": "item", "description": "10.1371/journal.pone.0020105", "href": "https://repository.soilwise-he.eu/cat/collections/metadata:main/items/10.1371/journal.pone.0020105"}, {"rel": "collection", "type": "application/json", "title": "Collection", "name": "collection", "description": "Collection", "href": "https://repository.soilwise-he.eu/cat/collections/metadata:main"}], "time": {"date": "2011-06-08T00:00:00Z"}}, {"id": "10.1890/06-1187.1", "type": "Feature", "geometry": null, "properties": {"license": "Closed Access", "updated": "2026-04-04T16:20:19Z", "type": "Journal Article", "created": "2007-07-19", "title": "Soil Responses To Management, Increased Precipitation, And Added Nitrogen In Ponderosa Pine Forests", "description": "Forest management, climatic change, and atmospheric N deposition can affect soil biogeochemistry, but their combined effects are not well understood. We examined the effects of water and N amendments and forest thinning and burning on soil N pools and fluxes in ponderosa pine forests near Flagstaff, Arizona (USA). Using a 15N-depleted fertilizer, we also documented the distribution of added N into soil N pools. Because thinning and burning can increase soil water content and N availability, we hypothesized that these changes would alleviate water and N limitation of soil processes, causing smaller responses to added N and water in the restored stand. We found little support for this hypothesis. Responses of fine root biomass, potential net N mineralization, and the soil microbial N to water and N amendments were mostly unaffected by stand management. Most of the soil processes we examined were limited by N and water, and the increased N and soil water availability caused by forest restoration was insufficient to alleviate these limitations. For example, N addition caused a larger increase in potential net nitrification in the restored stand, and at a given level of soil N availability, N addition had a larger effect on soil microbial N in the restored stand. Possibly, forest restoration increased the availability of some other limiting resource, amplifying responses to added N and water. Tracer N recoveries in roots and in the forest floor were lower in the restored stand. Natural abundance delta15N of labile soil N pools were higher in the restored stand, consistent with a more open N cycle. We conclude that thinning and burning open up the N cycle, at least in the short-term, and that these changes are amplified by enhanced precipitation and N additions. Our results suggest that thinning and burning in ponderosa pine forests will not increase their resistance to changes in soil N dynamics resulting from increased atmospheric N deposition or increased precipitation due to climatic change. Restoration plans should consider the potential impact on long-term forest productivity of greater N losses from a more open N cycle, especially during the period immediately after thinning and burning.", "keywords": ["Time Factors", "Nitrogen", "Climate", "Arizona", "Water", "04 agricultural and veterinary sciences", "15. Life on land", "Fires", "Pinus ponderosa", "Soil", "13. Climate action", "Chemical Precipitation", "0401 agriculture", " forestry", " and fisheries", "Ecosystem", "Nitrites"]}, "links": [{"href": "https://doi.org/10.1890/06-1187.1"}, {"rel": "related", "href": "https://repository.soilwise-he.eu/cat/collections/metadata:main/items/Ecological%20Applications", "name": "related record", "description": "related record", "type": "application/json"}, {"rel": "self", "type": "application/geo+json", "title": "10.1890/06-1187.1", "name": "item", "description": "10.1890/06-1187.1", "href": "https://repository.soilwise-he.eu/cat/collections/metadata:main/items/10.1890/06-1187.1"}, {"rel": "collection", "type": "application/json", "title": "Collection", "name": "collection", "description": "Collection", "href": "https://repository.soilwise-he.eu/cat/collections/metadata:main"}], "time": {"date": "2007-07-01T00:00:00Z"}}, {"id": "PMC9666553", "type": "Feature", "geometry": null, "properties": {"updated": "2026-04-04T16:29:07Z", "type": "Journal Article", "created": "2022-11-15", "title": "Microfluidic study in a meter-long reactive path reveals how the medium\u2019s structural heterogeneity shapes MICP-induced biocementation", "description": "AbstractMicrobially induced calcium carbonate (CaCO3) precipitation (MICP) is one of the major sustainable alternatives to the artificial cementation of granular media. MICP consists of injecting the soil with bacterial- and calcium-rich solutions sequentially to form calcite bonds among the soil particles that improve the strength and stiffness of soils. The performance of MICP is governed by the underlying microscale processes of bacterial growth, reactive transport of solutes, reaction rates, crystal nucleation and growth. However, the impact of pore-scale heterogeneity on these processes during MICP is not well understood. This paper sheds light on the effect of pore-scale heterogeneity on the spatiotemporal evolution of MICP, overall chemical reaction efficiency and permeability evolution by combining two meter-long microfluidic devices of identical dimensions and porosity with homogeneous and heterogeneous porous networks and real-time monitoring. The two chips received, in triplicate, MICP treatment with an imposed flow and the same initial conditions, while the inlet and outlet pressures were periodically monitored. This paper proposes a comprehensive workflow destined to detect bacteria and crystals from time-lapse microscopy data at multiple positions along a microfluidic replica of porous media treated with MICP. CaCO3 crystals were formed 1\uffc2\uffa0h after the introduction of the cementation solution (CS), and crystal growth was completed 12\uffc2\uffa0h later. The average crystal growth rate was overall higher in the heterogeneous porous medium, while it became slower after the first 3\uffc2\uffa0h of cementation injection. It was found that the average chemical reaction efficiency presented a peak of 34% at the middle of the chip and remained above 20% before the last 90\uffc2\uffa0mm of the reactive path for the heterogeneous porous network. The homogeneous porous medium presented an overall lower average reaction efficiency, which peaked at 27% 420\uffc2\uffa0mm downstream of the inlet and remained lower than 12% for the rest of the microfluidic channel. These different trends of chemical efficiency in the two networks are due to a higher number of crystals of higher average diameter in the heterogeneous medium than in the homogeneous porous medium. In the interval between 480 and 900\uffc2\uffa0mm, the number of crystals in the heterogeneous porous medium is more than double the number of crystals in the homogeneous porous medium. The average diameters of the crystals were 23\uffe2\uff80\uff9346\uffc2\uffa0\uffce\uffbcm in the heterogeneous porous medium, compared to 17\uffe2\uff80\uff9340\uffc2\uffa0\uffce\uffbcm in the homogeneous porous medium across the whole chip. The permeability of the heterogeneous porous medium was more affected than that of the homogeneous system, while the pressure sensors effectively captured a higher decrease in the permeability during the first two hours when crystals were formed and a less prominent decrease during the subsequent seeded growth of the existing crystals, as well as the nucleation and growth of new crystals.