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This book contains state-of-the-art reviews of organic phosphorus characterization and transformations in the environment. It includes 17 chapters organized into 3 main sections. Section 1 (3 chapters) describes analytical techniques used to characterize organic phosphorus compounds in environmental samples, with chapters dedicated to state-of-the-art procedures involving chromatographic separation, nuclear magnetic resonance spectroscopy and mass spectrometry. Section 2 (7 chapters) addresses the processes that control organic phosphorus behaviour in terrestrial and aquatic environments, including the origins, stabilization, hydrolysis (biotic and abiotic) and biological utilization of organic phosphorus. Section 3 (7 chapters) integrates these processes at the ecosystem level, with chapters synthesizing information on organic phosphorus in soils and aquatic systems, its interaction with other nutrient cycles and its transfer between terrestrial and aquatic environments. Two chapters (Chapters 15 and 16) in this section describe state-of-the-art models used to investigate the behaviour of organic phosphorus in both terrestrial and aquatic environments. The final chapter in this section summarizes the importance of organic phosphorus in the environment and identifies key areas towards which future research effort should be directed.

International audience ; This paper aims at analyzing the role of an environmental tax or an environmental subsidy as instruments for preserving phosphate reserves, for improving water quality by reducing eutrophication, and for increasing social welfare. Toward these goals, we use a duopoly model "à la Stack- elberg", assume the presence of a benevolent government that takes into account the bene.cial e¤ect of recycling in the social welfare function and refunds the revenue of the tax to the society. First, we .nd that taxing extracted phosphorus or subsidizing recycled phosphorus contributes to the postponement of the depletion of the resource and to the reduction of eutrophication. Second, we .nd that taxing extracted phosphorus reduces consumers.surplus, whereas subsidizing recycled phosphorus increases it. Third, we show that the subsidy set by the regulator is higher than the marginal bene.t of recycling, whereas the level of the tax with respect to the marginal social damage of pollution is ambiguous. Fourth, we state that the tax and the subsidy increase social welfare. Fifth, by way of com- parison, we .nd that if the regulator aims at saving phosphorus, reducing eutrophication and improving social welfare simultaneously, subsidizing recycled phosphorus is the best policy, but if he aims only at saving phos- phorus and reducing eutrophication, taxing extracted phosphorus is more optimal than subsidizing recycled phosphorus.

International audience ; This paper aims at analyzing the role of an environmental tax or an environmental subsidy as instruments for preserving phosphate reserves, for improving water quality by reducing eutrophication, and for increasing social welfare. Toward these goals, we use a duopoly model "à la Stack- elberg", assume the presence of a benevolent government that takes into account the bene.cial e¤ect of recycling in the social welfare function and refunds the revenue of the tax to the society. First, we .nd that taxing extracted phosphorus or subsidizing recycled phosphorus contributes to the postponement of the depletion of the resource and to the reduction of eutrophication. Second, we .nd that taxing extracted phosphorus reduces consumers.surplus, whereas subsidizing recycled phosphorus increases it. Third, we show that the subsidy set by the regulator is higher than the marginal bene.t of recycling, whereas the level of the tax with respect to the marginal social damage of pollution is ambiguous. Fourth, we state that the tax and the subsidy increase social welfare. Fifth, by way of com- parison, we .nd that if the regulator aims at saving phosphorus, reducing eutrophication and improving social welfare simultaneously, subsidizing recycled phosphorus is the best policy, but if he aims only at saving phos- phorus and reducing eutrophication, taxing extracted phosphorus is more optimal than subsidizing recycled phosphorus.

International audience ; This paper aims at analyzing the role of an environmental tax or an environmental subsidy as instruments for preserving phosphate reserves, for improving water quality by reducing eutrophication, and for increasing social welfare. Toward these goals, we use a duopoly model "à la Stack- elberg", assume the presence of a benevolent government that takes into account the bene.cial e¤ect of recycling in the social welfare function and refunds the revenue of the tax to the society. First, we .nd that taxing extracted phosphorus or subsidizing recycled phosphorus contributes to the postponement of the depletion of the resource and to the reduction of eutrophication. Second, we .nd that taxing extracted phosphorus reduces consumers.surplus, whereas subsidizing recycled phosphorus increases it. Third, we show that the subsidy set by the regulator is higher than the marginal bene.t of recycling, whereas the level of the tax with respect to the marginal social damage of pollution is ambiguous. Fourth, we state that the tax and the subsidy increase social welfare. Fifth, by way of com- parison, we .nd that if the regulator aims at saving phosphorus, reducing eutrophication and improving social welfare simultaneously, subsidizing recycled phosphorus is the best policy, but if he aims only at saving phos- phorus and reducing eutrophication, taxing extracted phosphorus is more optimal than subsidizing recycled phosphorus.

This paper aims at analyzing the role of an environmental tax or an environmental subsidy as instruments for preserving phosphate reserves, for improving water quality by reducing eutrophication, and for increasing social welfare. Toward these goals, we use a duopoly model "à la Stack- elberg", assume the presence of a benevolent government that takes into account the bene.cial e¤ect of recycling in the social welfare function and refunds the revenue of the tax to the society. First, we .nd that taxing extracted phosphorus or subsidizing recycled phosphorus contributes to the postponement of the depletion of the resource and to the reduction of eutrophication. Second, we .nd that taxing extracted phosphorus reduces consumers.surplus, whereas subsidizing recycled phosphorus increases it. Third, we show that the subsidy set by the regulator is higher than the marginal bene.t of recycling, whereas the level of the tax with respect to the marginal social damage of pollution is ambiguous. Fourth, we state that the tax and the subsidy increase social welfare. Fifth, by way of com- parison, we .nd that if the regulator aims at saving phosphorus, reducing eutrophication and improving social welfare simultaneously, subsidizing recycled phosphorus is the best policy, but if he aims only at saving phos- phorus and reducing eutrophication, taxing extracted phosphorus is more optimal than subsidizing recycled phosphorus.

Despite advances in modeling, such as graphical user interfaces, the use of GIS layers, and databases for developing input files, the approaches to modeling phosphorus (P) have not changed since their initial development in the 1980s. Current understanding of P processes has evolved and this new information needs to be incorporated into the current models. Filling this need, Modeling Phosphorus in the Environment describes basic approaches to modeling P, how the current models implement these approaches, and ways to improve them. The book sets the scene with a review of general approaches to modeling runoff and erosion, P in runoff, leaching of P, stream processes that affect P, and an examination of the important issue of model uncertainty. It describes state-of-the-science watershed-scale P transport models including dynamic semi-disturbed models, models of intermediate complexity, and two lumped models. Phosphorus Indexes (PIs) represent one end of the modeling spectrum and the book takes a comprehensive look at PIs developed in each state, and illustrates some of the problems encountered when incorporating PIs into farm-scale manure management software. The book discusses monitoring data, which is critical for calibrating models, and concludes with suggestions for improving the modeling of P. From researching mechanisms to applying regulations, the uses of phosphorus models have increased as our knowledge of the effects of phosphorus in the environment has increased. Drawing on contributions from experts, the book gives you the tools to select the model that best fits your needs.

Phosphorus is an essential nutrient for growth in all living organisms and is used as fertilizer to maintain food production. Today's recovery of mineral phosphate will lead to a lack of phos-phorus as mineral fertilizer since phosphorus will become more expensive over the time. In-creased awareness that the mineral phosphate is not a renewable resource means that recycling of phosphorus is an important environmental and food safety issue. In the given thesis, the recovery of phosphorus was carried out by the precipitation of the am-monium-magnesium-phosphate (struvite) complex. The overriding purpose was to determine the optimal parameters for phosphates removal through the struvite precipitation from the re-ject- and sludge- wastewater after the biological treatment from the HIAS sewage plant in Hamar, Norway. Furthermore, the goal was to achieve a struvite with the high nutrients content and use it as a potential fertilizer. To accomplish that goal it was formed hypotheses, made the experiments, analysis, and results. Based on the theory, three hypotheses were formed, which are focused on varying the parame-ters time, pH and molar ratio of Mg2+: NH4+. Firstly, an increase in pH from 8 to 8.3 should increase phosphorus removal through struvite precipitation. Secondly, the reaction time plays role in phosphorus recovery. Thus, the reaction time in the interval 20 to 60 min should be optimal for struvite formation with the high P-recovery. Thirdly, the molar ratio of Mg2+: NH4+ at 1.2: 10 and 1.5: 10: should cause about 95% of P removal. Finally, the concentration of toxic elements, such as heavy metals, was expected to meet the legislations requirements after the experiments. To carry out the experiments, two sources of wastewater have been taken from the HIAS, mixed and added the salt of magnesium. The solution has been mixed and centrifuged. Both the liquid part and the sediment (struvite) have been analyzed. The struvite was weighted and analyzed iv on the content of elements. The liquid part was analyzed on phosphorus and ammonium recov-ery, turbidity, conductivity and the content of elements. The results showed the highest phosphorus recovery of 97% was achieved by the Mg2+: NH4+ molar ratio of 1.5:10 and the pH 8.3, which looks like the optimum combination for PO43- re-covery. All the experiments showed the same ammonium recovery, at about 68.5%. 20 min reaction time showed better struvite removal than at 60 min. It was found that, although, the amount of struvite sedimentation was small, the quality of precipitated struvite was high. The struvite contains a very low number of toxic elements, which are less than in the legislations requirements. The results showed that the Mg2+: NH4+ molar ratio and the pH plays key role in enhancing of phosphorus recovery through struvite precipitation. Moreover, the changing in time also can affect the quality of struvite as a future fertilizer. ; M-MINA

There are several factors that need to be monitored to fully understand agricultural contributions to environmental degradation as well as the effectiveness of implementing sustainable practices. This study did so by sampling cow ponds from different locations in northern Virginia with different cattle exclusion methods to evaluate the phosphorus levels in each aquatic system. Through comparing these sites, there were conclusions shown through a statistical analysis to summarize both the current health of agricultural ponds compared to government recommended criteria and the effectiveness of varying forms of clean water practices. The data collection came from samples taken at six cattle farm ponds in northern Virginia that were collected in November 2021 and January 2022. The samples were compared using an ANOVA statistical analysis, which compared sample results by location. The findings of this study showed that all the test sites were above the recommended value by the EPA for the total P concentrations. There was also statistical significance shown through some of the locations, which provided partial credibility to the efficiency of clean water practices. These studies are important to both the overall issue of clean water in agricultural industry regions as well as the specific situation of Virginia agricultural practices. Currently under a voluntary stream exclusion program, there is potential for mandates to be put in place without a shown improvement in water quality by 2025. Taking progressional measurements into consideration it is clear that there is still a way to go to meet federal satisfaction. This study opens up the door for future research regarding the progress of clean water restoration efforts as well as the monitoring of agricultural impacts on overall regional water quality.

Phosphate rock and phosphorus are listed by the European Union as the critical raw materials due to the risks of their shortage of supply and the impacts of a shortage on the economy are greater than those of most other raw materials. Although, high concentration of P in surface waters is the leading cause of eutrophication, which is a serious environmental problem in many countries of the world. Eutrophication of both freshwater and coastal marine ecosystems leads to a decrease in oxygen concentration and increases the abundance of toxic algae and aquatic plants. Discharge of untreated or semi-treated wastewater into the environment is one of the main causes of eutrophication; therefore, it is necessary to use effective wastewater treatment methods. One of the possibilities for the removal of P from wastewater is the use of biomaterial sorbents modified by iron oxohydroxide, which is an alternative to traditional wastewater treatment methods. As a prospective solution for P removal from wastewaters peat and other biomaterials has been suggested and tested. The obtained sorbents characterize high sorption capacities, fast sorption and relatively high sorbent saturation capacities and possibilities to run sorption process both in static and dynamic conditions. The results showed that P can be efficiently removed from wastewater by modified biomaterial sorbents; furthermore, after the purification process sorbents saturated with P can be recycled and used as fertilizers in agriculture. The saturated sorbents can be composted and transformed to a high value fertilizer considering significant amounts of phosphorus as well as presence of iron and nitrogen compounds. Further tests using domestic wastewaters were done and the presence of metals as well as toxicity of the sorbents were tested, proving application prospects. Thus biomaterial based sorbents can be a feasible approach for phosphorus removal from wastewaters and return of nutrient for agricultural applications as well as reduction of phosphorus load to waters. This work was funded by the project "Sustainable Management of Phosphorus in Baltic countries" (InPhos) No. 17022 (2018-2019), that is financed by the EIT Raw Materials. ; Phosphate rock and phosphorus are listed by the European Union as the critical raw materials due to the risks of their shortage of supply and the impacts of a shortage on the economy are greater than those of most other raw materials. Although, high concentration of P in surface waters is the leading cause of eutrophication, which is a serious environmental problem in many countries of the world. Eutrophication of both freshwater and coastal marine ecosystems leads to a decrease in oxygen concentration and increases the abundance of toxic algae and aquatic plants. Discharge of untreated or semi-treated wastewater into the environment is one of the main causes of eutrophication; therefore, it is necessary to use effective wastewater treatment methods. One of the possibilities for the removal of P from wastewater is the use of biomaterial sorbents modified by iron oxohydroxide, which is an alternative to traditional wastewater treatment methods. As a prospective solution for P removal from wastewaters peat and other biomaterials has been suggested and tested. The obtained sorbents characterize high sorption capacities, fast sorption and relatively high sorbent saturation capacities and possibilities to run sorption process both in static and dynamic conditions. The results showed that P can be efficiently removed from wastewater by modified biomaterial sorbents; furthermore, after the purification process sorbents saturated with P can be recycled and used as fertilizers in agriculture. The saturated sorbents can be composted and transformed to a high value fertilizer considering significant amounts of phosphorus as well as presence of iron and nitrogen compounds. Further tests using domestic wastewaters were done and the presence of metals as well as toxicity of the sorbents were tested, proving application prospects. Thus biomaterial based sorbents can be a feasible approach for phosphorus removal from wastewaters and return of nutrient for agricultural applications as well as reduction of phosphorus load to waters. This work was funded by the project "Sustainable Management of Phosphorus in Baltic countries" (InPhos) No. 17022 (2018-2019), that is financed by the EIT Raw Materials.