ARTICLE | doi:10.20944/preprints202006.0288.v1
Subject: Engineering, Civil Engineering Keywords: Phosphorus fractions; Phosphorus; Sediment; Tiaoxi; Hongze; Watershed
Online: 24 June 2020 (08:54:31 CEST)
River sediment from two inflow watersheds (Hongze and Tiaoxi) to Hongze and Taihu Lake in Eastern China was analyzed by the sequential extraction procedure. This study aimed to explore a spatial distribution of phosphorus fractions in river sediments and analysed the relationship between different phosphorus fractions and their environmental influence on the sediments within different watersheds in Eastern China. Five fractions of sedimentary phosphorus, including freely sorbed phosphorus, were all analyzed (NH4Cl-P), redox-sensitive phosphorus (BD-P), bound phosphorus metal oxide (NaOH-P), bound phosphorus calcium (HCl-P) and residual phosphorus (Res-P). The order of rank of the P fractions for the river Anhe was HCl-P>NaOH-P>BD-P>NH4Cl-P; whereas that of the Suihe river was HCl-P>BD-P>NaOH-P>NH4Cl-P. For the rank order of the Hongze watershed, HCl-P was higher while the NH4Cl-P contents were significantly lower. The rank order for the Dongtiaoxi river was NaOH-P > HCl-P> BD-P> NH4Cl-P and that of Xitiaoxi river was NaOH-P> BD-P> HCl-P> NH4Cl-P. Compared with phosphorus forms of Tiaoxi watershed, NaOH-P contents were significantly higher in the converse of HCl-P contents were significantly higher in Hongze watershed while both in NH4Cl-P contents were significantly lower. Variations may be attributed to differential discharge of P watershed form due to land-use changes and urban river ambient conditions.
ARTICLE | doi:10.20944/preprints202009.0681.v1
Subject: Life Sciences, Biochemistry Keywords: phosphorus solubilization; plant growth promotion; biofertilizers; sustainable agriculture; phosphorus solubilizing bacteria; rhizobacteria
Online: 28 September 2020 (07:37:59 CEST)
Phosphorus (P) is the second-most important element after nitrogen that is required for plant growth. Although this element is abundant in most soils, it is rarely available in plant-accessible forms since most of it normally exists in soil in insoluble forms such as phosphates. In conventional agriculture, P is normally supplied as chemical fertilizer to satisfy plant P requirements. This, to a large extent, boosts plant production. However, chemical fertilizers are costly, have a huge carbon footprint, and are environmentally-unsustainable owing to the high energy requirements during their synthesis. Besides, P-containing agricultural run-offs contribute hugely to the eutrophication of water bodies and environmental degradation. Moreover, plants can consume only a small amount of chemically-supplied P since between 75 and 90% of this form of P normally get precipitated into complexes and rapidly become fixed in soil. These issues and concerns necessitate research into alternative and viable ways of supplying P to plants. Rhizobacteria have for decades been investigated in vivo and in planta as suitable tools in sustainable agriculture due to the plant-growth-promoting activities such as nutrients’ solubilization, nitrogen fixation, and production of phytohormones. Although a lot of research has been done on different nutrients-solubilizing rhizobacteria and their potential in sustainable agriculture, their mechanisms of action and prospects in sustainable agriculture remain to be fully understood. This review particularly focuses on the P solubilizing rhizobacteria and evaluates their diversity, mechanisms of action, and prospects in sustainable agriculture based on the present and future scenario of their application. Such information is useful in determining their potential and evaluating their prospects in promoting sustainable agricultural systems.
ARTICLE | doi:10.20944/preprints202211.0424.v1
Online: 22 November 2022 (11:58:34 CET)
Floodplains are critically important ecosystems that provide a whole suite of ecosystem services including nutrient and carbon sequestration, flood mitigation, water storage, and critical wildlife habitat to name a few. However, human modification of rivers and floodplains through channelization, artificial levee construction, reduction in active floodplain area, and water management can significantly reduce the ecosystem function of river-floodplain systems. In this study, we evaluated the changes in nutrient loading of the Kissimmee River floodplain during the restoration of the river-floodplain system. In addition to time-series loading analysis, we also evaluated soil nutrient concentrations across the lower portion of the Kissimmee River floodplain. During the 44-year nutrient loading time-series, the floodplain remained a nutrient exporter with changes in nutrient loading generally corresponding to both water quality (i.e. point source reductions) and hydrologic restoration activities in the watershed and Kissimmee River floodplain. During the study period, inputs of total phosphorus and total nitrogen loads from upstream either significantly increased or remained the same. In addition to external sources of nutrients, internal sources of nutrients from floodplain soils can also contribute to the total nutrient export from the system. These internal sources could be organic via the decomposition of organic matter or geologic from the original excavation of the canal and/or restoration backfilling. Soil nutrient concentrations vary between vegetative communities and landscape position and could be a significant source of phosphorus to the downstream system which is plagued by eutrophic conditions. Therefore, as floodplain function in the Kissimmee River continues to be restored and managed, additional effort may be needed to address nutrient inputs and internal legacy nutrients.
SHORT NOTE | doi:10.20944/preprints201712.0165.v1
Subject: Chemistry, Organic Chemistry Keywords: aromatic hydrazide condensation; phosphorus heterocycles; cytotoxicity;
Online: 25 December 2017 (07:00:47 CET)
5-Methyl-3,8-di-(2-amino-4-bromophenyl)-4,9-dioxa-1,2,6,7-tetraaza-5λ5-phosphaspiro[4.4]nona-2,7-diene was obtained in a condensation reaction of 2-amino-5-bromobenzohydrazide and methylphosphonyl dichloride in the presence of triethylamine. An initial biological screening was performed for the obtained product. The synthesized compound possesses two aromatic primary amine groups and two bromine atoms within the structure, which are suitable for further structural modifications.
ARTICLE | doi:10.20944/preprints202201.0201.v1
Subject: Earth Sciences, Environmental Sciences Keywords: wastewater; valuable algal biomass; nitrogen; phosphorus; jellyfish
Online: 14 January 2022 (11:18:16 CET)
The introduction of organic and inorganic substances to the environment is a result of human activities such as agriculture, domestic and industrial wastewater which leads to pollution. Treatment processes of these wastewaters are being conducted globally to eliminate easily settled materials and recover nutrients in an attempt to release clear and apparently clean effluent into natural waters. Lack of removing inorganic nitrogen and phosphorus nutrients is the greatest cause of eutrophication in water bodies which inhibits the life of other organisms as well as pose a threat to human life and loss of the economy. Different technologies have been applied and are being developed to recover nutrients as well as heavy metals from wastewater to meet the permissible limits before discharging effluents. Wastewater treatment using microalgae offers an opportunity to provide tertiary bio-treatment and production of valuable biomass. Microalgae use the available inorganic nitrogen and phosphorus for their growth which are then harvested for various uses. Additionally, they have the ability to remove heavy metals and some toxic compounds. The main specific microalgae species in this study is the Chlorella sorokiniana with the Aequorea victoria jellyfish This paper reviews some of the wastewater treatment processes and focus on the use of microalgae and some of the shortcomings of the technologies and how they can be improved to achieve maximum nutrient recovery economically with low energy demand.
ARTICLE | doi:10.20944/preprints201804.0316.v1
Subject: Engineering, General Engineering Keywords: phosphorus; N:P ratio; cyanobacteria; Planktothrix agardhii; Lake Vombsjön
Online: 24 April 2018 (10:12:39 CEST)
Control of nutrients, mainly nitrogen (N) and phosphorus (P), plays a significant role in preventing cyanobacterial blooms (harmful algal blooms (HABs)). This study aimed at evaluating changes in the risk of the occurrence of cyanobacterial blooms and advancing the understanding of how N and P affect the growth of cyanobacteria in a eutrophic lake, Lake Vombsjön, in southern Sweden. Statistical analysis was used to demonstrate the pattern of cyanobacterial blooms, that the highest content present in September and the later that algal blooms occur, the more likely it is a cyanobacterial bloom as cyanobacteria became dominating in October and November (90%). Two hypothesises tested in Lake Vombsjön confirmed namely that a high total phosphorus (TP) level correlates with an abundance of cyanobacteria and that low N:P ratio (total nitrogen/total phosphorus < 20) favours the growth of cyanobacteria. To control the growth of cyanobacteria in Lake Vombsjön, the TP level should be kept below 20 µg/L and the N:P ratio be maintained at a level of over 20. The two species Planktothrix agardhii, and Pseudanabaena spp. should be carefully monitored especially in late autumn. Future work should consider any high degree of leakage from the sediment of the dissolved phosphorus available there.
REVIEW | doi:10.20944/preprints201610.0036.v2
Subject: Chemistry, Organic Chemistry Keywords: 2-halo-1,2λ5-oxaphosphetanes; allylphosphonates; vinylphosphonates; phosphorus ketenes
Online: 14 October 2016 (10:14:32 CEST)
Abstract. Results of research into four-membered phosphorus(V)-heterocycles, 2-halogen-1,2λ5-oxaphosphetanes are presented. The preparation of 2-halo-1,2λ5-oxaphosphetanes by reaction of P-haloylides with carbonyl compounds is described. The mechanism of asynchronous [2+2]-сycloaddition of ylides to aldehydes was proposed on the base of low-temperature NMR investigations. 2-Halogen-1,2λ5-oxaphosphetanes were isolated as individual compounds and their structures were confirmed by 1Н, 13C, 19F and 31Р NMR spectra. These compounds are convenient reagents for preparing of various organic and organophosphorus compounds hardly available by other methods. Chemical and physical properties of the 2-halo-1,2λ5-oxaphosphetanes are reviewed. The 2-chloro-1,2λ5-oxaphosphetanes depending on substituents at the α-carbon atom rearrange with formation of 2-chloroalkylphosphonates or convert into trans-phosphorylated alkenes. Prospective synthetic applications of 2-halo-1,2λ5-oxaphosphetanes are analyzed. The 2-halo-1,2λ5-oxaphosphetanes may be easily converted to various alkenylphosphonates: allyl- or vinylphosphonates, phosphorus ketenes, thioketenes, ketenimines.
ARTICLE | doi:10.20944/preprints202212.0028.v1
Subject: Life Sciences, Other Keywords: free-range system; hen runs; nitrogen; phosphorus; organic matter.
Online: 1 December 2022 (16:11:03 CET)
To evaluate the nutrient load due to the grazing of laying hens in outdoor runs, soil characteristics were monitored in three Italian organic farms. For each farm, soil samples were taken from three increasing distances from the hen house and two depths and different chemical parameters were evaluated. The comparison among the results from the different distances shows that N-NO3 and Olsen P are the most affected parameters by hen faeces: both present high values with a statistically significant difference in the area close to the poultry house and for the most superficial layer. Even TKN and TOC show significant differences between the concentrations of the first layer (more concentrated) and those of the second layer (less concentrated). In general, the surface soil layer closest to the chicken house is the portion of the outdoor run most affected by chicken droppings and represents the most critical point in terms of potential environmental impact. Therefore, it is necessary to intensify the management of the outdoor run with tools that can facilitate the grazing of animals and with vegetation that can absorb nutrients by limiting leaching and run-off.
ARTICLE | doi:10.20944/preprints202110.0340.v1
Subject: Biology, Agricultural Sciences & Agronomy Keywords: eutrophication; phosphorus sorption; soil Olsen P; soil organic matter
Online: 25 October 2021 (10:40:00 CEST)
The Mediterranean region offers good weather conditions for outdoor pig production (OPP), which is considered more environmentally friendly than intensive indoor production. However, the continuous input of food and pigs' excreta increases the soil organic matter (SOM) and phosphorus (P), increasing the risk of waterbodies eutrophication. This work aimed at evaluating in OPP areas soil P dynamics and the role of SOM on P sorption and P release. The experiment was done for two years, at an area of 2.8 ha with an animal charge of 9 adults ha-1. Georeferenced soil samples were taken at 0.20 m depth, and a soil P sorption experiment was carried out. At the end of the experiment, for the background value, the levels of SOM increased between 85–376%, and Olsen P values ranged between -82–884%. SOM levels above 2% caused a decrease in the binding energy of P sorption according to the linear model b=-15.541SOM+115.20 (p <0.01) as well as a decrease of the soil P sorption capacity Qmax=-41.272SOM+298.37 (p <0.01). To avoid the accumulation of SOM and P preventing hotspots for waterbodies eutrophication, an adequate animal charge together with soil cultivation for pig grazing can be a cost-effective practice.
ARTICLE | doi:10.20944/preprints202107.0522.v1
Subject: Biology, Anatomy & Morphology Keywords: Biogeographic Chocó; Carbon balance; Nutritional limitation; Nitrogen; Phosphorus; Potassium
Online: 22 July 2021 (14:14:30 CEST)
Tropical rainforests have the highest rates of net primary productivity (NPP) of the world. Hypotheses about the effect of edaphic nutrient contents, especially the availability of P, propose that they limit NPP of tropical forests or promote the redistribution of its above and belowground components. However, these hypotheses have not been tested experimentally in highly rainy tropical forests. To test such hypotheses, the effects of soil fertilization on the above and belowground NPP were evaluated in forests of two localities of Chocó (Colombia), one of the rainiest regions of the world. Five fertilization treatments (N, P, K, NPK and Control) were applied, and the above and belowground NPP were determined in permanent plots. There were no significant effects of treatments on total NPP; only the application of N significantly increased litter NPP. Additionally, a redistribution of the above and belowground NPP was found with the application of P, which increased the proportion of fine roots and litter, and decreased the woody components of forest NPP. This change of carbon allocation is interpreted as an ecophysiological mechanism to capture additional nutrients in soils with very low content of available P.
ARTICLE | doi:10.20944/preprints202212.0100.v1
Subject: Engineering, Other Keywords: olive solid waste; cow manure; phosphorus; potassium; cation exchange capacity
Online: 6 December 2022 (10:06:43 CET)
A field experiment was conducted on the farm of Abi Jarash in Agricultural Collage, different rates of olive solid waste and cow manure were used, as follows: (control, fresh olive solid waste 100%, fresh olive solid waste 75%+ cow manure 25%, fresh olive solid waste 50%+ cow manure 50%, fresh olive solid waste 25+ cow manure 75%, Fermented Olive Solid Waste 100%, Fermented olive solid waste 75%+ cow manure 25%, Fermented olive solid waste 50%+ cow manure 50%, Fermented olive solid waste 25+ cow manure 75%), wheat was seeded. The impact of fresh and fermented olive solid waste and cow manure on some chemical and fertility soil properties was studied. the olive solid waste treatment 100% which added had more effect on the organic matter, exchange capacity, nitrogen, phosphorus and potassium in soil, plant and productivity, after that the fermented olive solid waste 75% + cow manure, fresh olive solid waste 100% comparing with the control, the values of organic matter were (25% 2.73, 2.39) and the cation exchange capacity (21.76, 20.44, 19.38) and for phosphorus (303.3, 277.8, 171.8) mg / kg, while the values of potassium were (303.3, 277.8, 171.8) mg / kg. In terms of plant content, the plant content of nitrogen, phosphorus and potassium were the same as for grains (2.784, 2.606, 2.126), (0.4535, 0.4226, 0.2753), (1.876, 1.762, 1.234) respectively, (0.2875, 0.2016) respectively for the same previous treatments and elements. olive solid waste 100% was the highest productivity comparing with the other treatments, where the productivity of wheat was (9.513) ton. ha-1.
ARTICLE | doi:10.20944/preprints201911.0270.v1
Subject: Earth Sciences, Environmental Sciences Keywords: nitrogen; phosphorus; nutrient cycling; biogeochemistry; geochemistry; geophysics; wetlands; catchment management
Online: 24 November 2019 (05:05:30 CET)
The impact of riparian wetlands on the cycling, retention and export of nutrients from land to water varies according to local environmental conditions and is poorly resolved in catchment management approaches. To determine the role a specific wetland might play in a catchment mitigation strategy, an alternative approach is needed to the high frequency and spatially detailed monitoring programme that would otherwise be needed. Here, we present a new approach using a combination of novel and well-established geochemical, geophysical and isotope ratio approaches. This was developed and tested against a 2-year high-resolution sampling programme in a lowland permeable wetland in the Lambourn catchment, UK. The monitoring programme identified multiple pathways and water sources feeding into the wetland, generating large spatial and temporal variations in nutrient cycling, retention and export behaviours within the wetland. This complexity of contributing source areas and biogeochemical functions within the wetland were effectively identified using the new toolkit approach. We propose that this technique could be used to determine the likely net source/sink function of riparian wetlands prior to their incorporation into any catchment management plan, with relatively low resource implications when compared to a full high frequency nutrient speciation and isotope geochemistry-based monitoring approach.
ARTICLE | doi:10.20944/preprints201811.0521.v1
Subject: Earth Sciences, Environmental Sciences Keywords: phosphorus; nutrient budget; non-point source pollution; Korea; monsoon climate
Online: 21 November 2018 (07:28:35 CET)
Despite increased awareness of and attention to the need for sustainable agriculture, fertilizers and compost application in excess of crop requirements remain common agricultural practices in South Korea, causing eutrophication of freshwater and coastal ecosystems. In this study, a phosphorus (P) budget was developed to quantify P inputs, outputs, and retention in a forested- agricultural watershed. The P budget showed that chemical fertilizers and organic compost were the largest source of P (97.6% of the total) followed by atmospheric deposition (2.1% of the total P), whereas forest export (0.2% of the total) and sewage treatment plants (STPs) (0.1% of the total) were negligible. The dominant P outputs were crop harvesting and hydrologic export to surface water. The P balance showed a significant accumulation of P in the watershed; approximately 87% of the total P input was retained in the soils within the watershed. However, P concentrations in drainage water were still high enough to cause eutrophication of downstream reservoirs. The results provide useful information on the proportion of P export and retention in soils and will help support efforts to improve water quality and design better management of agricultural non-point source pollution.
ARTICLE | doi:10.20944/preprints201810.0410.v1
Subject: Earth Sciences, Environmental Sciences Keywords: Anion exchange, DOC, Dissolved phosphorus, Forest soil, Lysimeters, P transport
Online: 18 October 2018 (10:10:20 CEST)
Incidental P losses from non-point sources may contribute to eutrophication and to decreased soil fertility. These incidents have been related to heavy rainfall on freshly fertilized agricultural soils and little is known about such incidents on more natural soils or in forests. The aim of this work is to determine if incidents of high P leaching also occur in spruce forests, and if such incidents are of significance in P cycling. We found a peak in the mineral soil solution showing that single events of high P leaching occur. The orthophosphate concentration in the Bf-horizon of the 80-year old spruce forest peaked in the autumn of the second year of a continuous monitoring. The concentration increased by more than 85 times compared to the highest concentration obtained earlier during the sampling. The amount leached during this 6 months peak is 10 times higher than the average annual leaching. This P leaching might be due to a combination of high P deposition/through-fall and a high anion exchange with dissolved-organic-carbon and Cl-. We suggest that single events of high sub-surface P leaching may contribute to the overall P leaching, and might increase with the global warming as more DOC is expected to be released to the soil solution.
ARTICLE | doi:10.20944/preprints201809.0207.v1
Subject: Biology, Plant Sciences Keywords: Phosphorus deficiency, common bean, rhizobia, molecular dialog, symbiosis, gene transcription
Online: 12 September 2018 (01:29:38 CEST)
Phosphate (Pi) deficiency reduces nodule formation and development in different legume species including common bean. Despite the significant progress in the understanding of the genetic responses underlying the adaptation of nodules to Pi deficiency, it is still unclear whether this nutritional deficiency interferes with the molecular dialog between legumes and rhizobia, if so, what part of the molecular dialog is impaired? In this study, we provide evidence demonstrating that Pi deficiency negatively affects critical early molecular and physiological responses required for a successful symbiosis between common bean and rhizobia. We demonstrated that the infection thread formation and the expression of PvNSP2, PvNIN, and PvFLOT2, genes controlling the nodulation process, were significantly reduced in Pi-deficient common bean seedlings. Further transcriptional analysis revealed that the expression of hormones-related genes is compromised in Pi-deficient seedlings inoculated with rhizobia. Additionally, we showed that regardless of the presence or absence of rhizobia, the expression of PvRIC1 and PvRIC2, two genes participating in the autoregulation of nodule number, was higher in Pi-deficient seedlings than in control seedlings. The data presented in this study shed light on the understanding of how Pi deficiency impacts the early steps of the symbiosis between common bean and rhizobia.
ARTICLE | doi:10.20944/preprints202007.0490.v1
Subject: Chemistry, Inorganic & Nuclear Chemistry Keywords: Carbodiphosphorane; Phosphorus Ylides; Pincer Ligands; Coordination Chemistry; Cu(I) complex; Photoluminescence
Online: 21 July 2020 (12:52:11 CEST)
A series of dinuclear copper(I) N,C,N- and P,C,P-carbodiphosphorane (CDP) complexes using multidentate ligands CDP(Py)2 (1) and (CDP(CH2PPh2)2 (13) have been isolated and characterized. Detailed structural information was gained by single crystal XRD analyses of nine representative examples. The common structural motive is the central double ylidic carbon atom with its characteristic two lone-pairs involved into binding of two geminal L-Cu(I) fragments at Cu-Cu distances in the range 2.55 – 2.67 Å. In order to enhance conformational rigidity within the characteristic Cu-C-Cu triangle, two types of chelating side arms were symmetrically attached to each phosphorus atom: two 2-pyridyl functions in ligand CDP(Py)2 (1) and its dinuclear copper complexes 2-9 and 11, as well as two diphenylphosphinomethylene functions in ligand CDP(CH2PPh2)2 (13) and its di- and mononuclear complexes 14-18. Neutral complexes were typically obtained via reaction of 1 with Cu(I) species CuCl, CuI, and CuSPh or via salt elimination reaction of [(CuCl)2(CDP(Py)2] (2) with sodium carbazolate. Cationic Cu(I) complexes were prepared upon treating 1 with two equivalents of [Cu(NCMe)4]PF6, followed by the addition of either two equivalent of an aryl phosphine (PPh3, P(C6H4OMe)3) or one equivalent of a bisphosphine ligands DPEPhos, XantPhos or dppf. For the first time carbodiphosphorane CDP(CH2PPh2)2 (13) could be isolated upon treating its precursor [CH(dppm)2]Cl (12) with NaNH2 in liquid NH3. A protonated and a deprotonated derivative of ligand 13 were prepared and their coordination was compared to neutral CDP ligand 13. NMR analysis and DFT calculations reveal, that the most stable tautomer of 13 does not show a CDP (or carbone) structure in its uncoordinated base form. For most of the prepared complexes, photoluminescence upon irradiation with UV light at room temperature was observed. Quantum yields (PL) were determined to 36% for dicationic [(CuPPh3)2(CDP(Py)2)](PF6)2 (4) and to 60% for neutral [(CuSPh)2(CDP(CH2PPh2)2] (16).
ARTICLE | doi:10.20944/preprints202212.0432.v1
Subject: Engineering, Industrial & Manufacturing Engineering Keywords: supply chain management; phosphorus fertilizers; environmental issues; sustainability; recycling policy; metaheuristic algorithm
Online: 23 December 2022 (01:39:06 CET)
Phosphorus (P) is the most important substance in inorganic fertilizers used in agriculture industry. In this study, a multi-product and multi-objective model is presented considering economic and environmental concerns to design a renewable and sustainable P-fertilizer supply chain management (PFSCM). To handle complexities of the proposed model, an ensemble knowledge-based three-stage heuristic-metaheuristic algorithm utilizing heuristic information available in the model, whale optimization algorithm, and variable neighborhood search (named H-WOA-VNS) is proposed. At first, a problem-dependent heuristic is designed to generate a set of near-optimal feasible solutions. These solutions are fed into a population-based whale optimization algorithm which benefits from both exploration and exploitation strategies. Finally, a single-solution metaheuristic based on variable neighborhood search is applied to further improve the quality of the solution using local search operators. The objective function of the algorithm is formulated as a weighted average function to minimize total economic cost, while increasing crop yield and P use efficiency. Experimental results over five synthetic datasets and a real case study of the P-fertilizer supply chain confirm the superiority of the proposed method against the state-of-the-art techniques. The results demonstrate that the proposed method performs well in optimizing both the economic cost and environmental issues.
ARTICLE | doi:10.20944/preprints201807.0322.v1
Subject: Earth Sciences, Environmental Sciences Keywords: stormwater; monitoring; gross pollutant generation rates; suspended solids; nitrogen; phosphorus; heavy metals
Online: 18 July 2018 (09:07:46 CEST)
Urban stormwater runoff from a medium-density residential development in southeast Queensland has been monitored in the field since November 2013. A treatment train installed on the site includes rainwater tanks collecting roofwater, 200-micron mesh baskets installed in grated gully pits and two 850 mm high media filtration cartridges installed in an underground 4 m3 vault. A monitoring protocol developed by research partners, Queensland University of Technology (QUT), guided the monitoring process over a 4.5-year period. Heavy metals were included in the list of analytes during the monitoring period as the catchment is within 1 km of the environmentally-sensitive Moreton Bay, Queensland. Removal efficiencies observed at this site for the regulated pollutants; total suspended solids (TSS), total phosphorus (TP) and total nitrogen (TN) for the pit baskets were 61%, 28% and 45% respectively. The cartridge filters removed 78% TSS, 59% TP, 42% TN, 40% total copper and 51% total zinc. As the measured influent concentrations to the cartridge filters were low when compared to industry guidelines, the dataset was merged with international field results for TSS (n=39) and TP (n=32) but truncated within anticipated guideline levels. The combined dataset for the media filter demonstrates performance at 89% TSS, 66% TP and 42% TN. The total gross pollutant generation rate from the medium-density residential catchment was observed to be 0.24 m3/Ha/year, with a corresponding air-dried mass of 142.5 kg/Ha/year. Less than 2% of the gross pollutant mass was anthropogenic. The findings of this research suggest that the treatment train, and in particular the media filter, holds promise for the removal of total copper and total zinc, in addition to TSS, TP and TN, from urban stormwater runoff. Based on a maximum, low risk trigger TN concentration of 1.5 mg/L, the field test data from 4.5 years of operation and standard maintenance, suggests a 5.5-year replacement interval for the media filters.
ARTICLE | doi:10.20944/preprints201805.0403.v1
Subject: Chemistry, Analytical Chemistry Keywords: eccentric-connectivity index; augmented eccentric-connectivity index; molecular graph; phosphorus containing dendrimers
Online: 28 May 2018 (12:40:03 CEST)
In the study of QSAR/QSPR, due to high degree of predictability of pharmaceutical properties, the eccentric-connectivity index has very important place among the other topological descriptors, In this paper, we compute the exact formulas of eccentric-connectivity index and its corresponding polynomial, total eccentric-connectivity index and its corresponding polynomial, first Zagreb eccentricity index, augmented eccentric-connectivity index, modified eccentric-connectivity index and its corresponding polynomial for a class of phosphorus containing dendrimers.
ARTICLE | doi:10.20944/preprints202108.0460.v1
Subject: Biology, Horticulture Keywords: Cannabis; cannabinoids; nutrients; nitrogen (N); phosphorus (P); potassium (K); yield; response surface methodology
Online: 24 August 2021 (08:40:44 CEST)
Following legalization, cannabis has quickly become an important horticultural crop in Canada and increasingly so in other parts of the world. However, due to previous legal restrictions on cannabis research there are limited scientific data on the relationship between nitrogen (N), phosphorus (P), and potassium (K) supply (collectively: NPK) and the crop yield and quality. This study examined the response of a high delta-9-tetrahydrocannabinol (THC) Cannabis sativa cultivar grown in deep-water culture with different nutrient solution treatments varying in their concentrations (mg L-1) of N (70, 120, 180, 250, 290), P (20, 40, 60, 80, 100) and K (60, 120, 200, 280, 340) according to a central composite design. Results demonstrated that inflorescence yield responded quadratically to N and P, with the optimal concentrations predicted to be 194 and 59 mg L-1, respectively. Inflorescence yield did not respond to K in the tested range. These results can provide guidance to cultivators when formulating nutrient solutions for soilless cannabis production and demonstrates the utility of surface response design for efficient multi-nutrient optimization.
ARTICLE | doi:10.20944/preprints201807.0216.v1
Subject: Life Sciences, Other Keywords: nutrient use efficiency; grain yield; nitrogen, phosphorus; potassium; green super rice; BC breeding
Online: 12 July 2018 (11:05:46 CEST)
To develop green super rice varieties with high and stable yields under the rainfed conditions and improved nutrient use efficiency (NuUE), a modified backcross (BC) breeding approach was adopted using a high yielding and widely adaptable Xian variety, WTR1, as the recipient and a Geng variety, HAN, as the donor. Starting from the BC1F2 generation, the BC population had gone through one generation of selection under the IG, LI and RF conditions, followed by consecutive four generations of screening and selection for high GY under six different nutrient conditions, leading to the development of 230 BC1F6 introgression lines (ILs). The final evaluation of the 230 ILs under the six nutrient conditions identified many ILs with improved yields under various combinations of nutrient deficient conditions, including 12 promising lines that had significantly improved NuUE under two or more nutrient deficiency conditions. Our results demonstrated an efficient inter-subspecific BC breeding procedure with first round selection under the rainfed-drought condition followed by four generations of progeny testing for yield performances under six different nutrient conditions. The promising ILs were studied under replicated yield trials under 75N and -NPK conditions for developing high yield rice varieties with improved NuUE. Our results indicated that NuUE in rice was controlled by complex genetic and physiological mechanisms and the developed ILs provided useful materials for genetic and molecular dissection of NuUE in rice.
Subject: Materials Science, Biomaterials Keywords: dephosphorization; distribution ratio of phosphorus; low temperature; low basicity; Fe2O3 addition amount; hot metal
Online: 8 February 2021 (10:38:30 CET)
The influence of the Fe2O3 addition amount on the dephosphorization of hot metal at 1623 K with the slag of the low basicity (CaO/SiO2) of about 1.5 was investigated by using high-temperature laboratorial experiments. With increasing the Fe2O3 addition amount, the contents of [C], [Si], [Mn] and [P] in hot metal at the end of dephosphorization decrease, and the corresponding removal ratios increase. The P2O5 content in slag increases, and the CaO and SiO2 contents in slag decrease. The phosphorus mainly exists in the form of the nCa2SiO4-Ca3(PO4)2 solid solution in the phosphorus-rich phase and the value of coefficient n decreases from 20 to 1 with increasing the Fe2O3 addition amount from 5 g to 30 g. With increasing the Fe2O3 addition amount, the oxygen potential and activity at the interface between the slag and hot metal increase. When the oxygen potential and the oxygen activity at the interface are greater than 0.72×10-12 and 7.1×10-3, respectively, the dephosphorization ratio begins to increase rapidly. With increasing the Fe2O3 addition amount to 30 g, the ratio of the Fe2O3 addition amount to theoretical calculation consumption is around 175%, and the dephosphorization ratio reaches the highest value of 83.3%.
ARTICLE | doi:10.20944/preprints201912.0077.v1
Subject: Earth Sciences, Environmental Sciences Keywords: Sub-Saharan Africa; phosphorus XANES; fertilizer microdosing; African leafy vegetables; synchrotron; sustainability; nutrient stewardship
Online: 6 December 2019 (04:48:26 CET)
This study investigated the speciation, transformation and availability of P during indigenous vegetable production by employing a combination of chemical and spectroscopic techniques. The study focused upon sites in two ecozones of SSA, the Dry Savanna (lna, Benin Republic) and Rainforest (Ilesha, Nigeria). Both sites were cultivated with two indigenous vegetable species; local amaranth (Amaranthus cruentus (AV)) and African eggplant (Solanum macrocarpon (SM)). The soils were treated with 5 t/ha poultry manure and urea fertilizer at the rate of 0, 20, 40, 60 and 80 kg N/ha. Soil samples were collected before planting and after harvest. Phosphorus K-edge X-ray absorption near-edge structure (XANES) spectroscopy was used to determine P speciation in these soils. Quantitative analysis showed that adsorbed and organic P were the two dominant P species in the manure amended Dry Savanna (DS) soils before planting and after harvest in soils cultivated with both AV and SM, with the addition of urea (40 kg N/ha) causing an increase in the organic P form in Dry Savanna soils cultivated with AV. Soils of the Rainforest (RF) cultivated with AV initially had large amounts of apatite P in the manure amended soils prior to planting which was transformed to adsorbed and organic P after harvest. Urea addition to the Rainforest soils shifted the dominant P species from organic P to adsorbed and apatite P, which is likely to limit P availability. Soils cultivated with SM had similar proportions of both organic and adsorbed P forms, with 40 kg N/ha addition slightly increased the proportion of adsorbed P.
ARTICLE | doi:10.20944/preprints201804.0132.v1
Subject: Engineering, Industrial & Manufacturing Engineering Keywords: bio-phosphate; ABC Animal-Bone-Char; 3R pyrolysis; phosphorus recovery; animal by-products; apatite
Online: 10 April 2018 (16:28:11 CEST)
Disrupted nutrient recycling is a significant problem for Europe, while phosphorus and nitrogen are wasted instead of being used for plant nutrition. Mineral phosphate is critical raw material, which contains environmentally hazardous elements such as cadmium and uranium. Therefore, phosphorus recovery from agricultural by-product streams is critically important key priority. Phosphorus recovery from food grade animal bone by-products have been applied researched since 2002 with objective driven evolution progress towards specialized pyrolysis processing technology and animal bone char product (ABC) developments in economical industrial scale. Different animal bone by-products tested under different conditions at 400 kg/h throughput capacity in the continuously operated 3R zero emission autothermal carbonization system. The different material core treatment temperatures (between >300°C and <850°C) were combined with different residence times under industrial productive processing conditions. It has been industrial demonstrated that material core treatment temperature <850°C with 20 minutes residence time is necessary to achieve high quality ABC with useful agronomic value. The output ABC product having concentrated >30% phosphorus pentoxide (P2O5) and specific quality innovative fertilizer for agronomical efficient organic and low input farming applications as functional organic fertilizer, soil improver, growing medium and/or fertilizing product blend with high mineral phosphate fertiliser replacement value.
ARTICLE | doi:10.20944/preprints202112.0192.v1
Subject: Engineering, Industrial & Manufacturing Engineering Keywords: End-point phosphorus content; Deep extreme learning machine; Sparrow search algorithm; Trigonometric substitution; Cauchy mutation
Online: 10 December 2021 (15:04:59 CET)
：An effective technology for predicting the end-point phosphorous content of basic oxygen furnace (BOF) can provide theoretical instruction to improve the quality of steel via controlling the hardness and toughness. Given the slightly inadequate prediction accuracy in the existing prediction model, a novel hybrid method was suggested to more accurately predict the end-point phosphorus content by integrating an enhanced sparrow search algorithm (ESSA) and a multi-strategy with a deep extreme learning machine (DELM) as ESSA-DELM in this study. To begin with, the input weights and hidden biases of DELM were randomly selected, resulting in that DELM inevitably had a set of non-optimal or unnecessary weights and biases. Therefore, the ESSA was used to optimize the DELM in this work. For the ESSA, the Trigonometric substitution mechanism and Cauchy mutation were introduced to avoid trapping in local optima and improve the global exploration capacity in SSA. Finally, to evaluate the prediction efficiency of ESSSA-DELM, the proposed model was tested on process data of the converter from the Baogang steel plant. The efficacy of ESSA-DELM was more superior to that of other DELM-based hybrid prediction models and conventional models. The result demonstrated that the hit rate of end-point phosphorus content within ±0.003%, ±0.002%, and ±0.001% was 91.67%, 83.33%, and 63.55%, respectively. The proposed ESSA-DELM model could possess better prediction accuracy compared with other models, which could guide field operations.
ARTICLE | doi:10.20944/preprints201804.0094.v1
Subject: Materials Science, Other Keywords: surface; textiles; flame retardant; plasma; ultraviolet; durability; phosphorus; nitrogen; polyurethane; thermal analysis; scanning electron microscopy
Online: 8 April 2018 (11:59:49 CEST)
Conventional flame retardant (FR) application processes for textiles involve aqueous processing which is resource intensive in terms of energy and water usage. Recent research using sol-gel and layer-by-layer chemistries, while claimed to be based on more environmentally-sustainable chemistry, still require aqueous media with the continuing problem of water management and drying processes being required. This paper outlines the initial forensic work to characterise commercially produced viscose/flax, cellulosic furnishing fabrics which have had conferred upon them durable flame retardant (FR) treatments using a novel, patented atmospheric plasma/UV excimer laser facility for processing textiles with the formal name - Multiplexed Laser Surface Enhancement (MLSE) system. This system (MTIX Ltd., UK), is claimed to offer the means of directly bonding of flame retardant precursor species to the component fibres introduced either before plasma/UV exposure or into the plasma/UV reaction zone itself, thereby eliminating a number of wet processing cycles. Nine commercial fabrics, pre-impregnated with a semi-durable, proprietary FR finish and subjected to the MLSE process have been analysed for their flame retardant properties before and after a 40 °C 30 min water soak. For one fabric, the pre-impregnated fabric was subjected to a normal heat cure treatment which conferred the same level of durability as the plasma/UV-treated analogue. TGA and LOI were used to further characterise their burning behaviour and the effect of the treatment on surface fibre morphologies were assessed. Scanning electron microscopy indicated that negligible changes had occurred to surface topography of the viscose fibres occurred during plasma/UV excimer processing.
ARTICLE | doi:10.20944/preprints202112.0232.v1
Subject: Biology, Agricultural Sciences & Agronomy Keywords: Sweet potato; Phosphorus fertilizer; Bacillus megaterium DSM2894; leaf and tuberous root nutrients contents; Tuberous root yield
Online: 14 December 2021 (12:15:41 CET)
Under Egyptian soil conditions, when phosphorus fertilizers were applied to the soil, it gets fixed and converts to unavailable form, leading to low solubility for the plant. This study were fulfilled on sweet potato (cv. Beauregard) under undesirable soil properties (CaCO3 10.8 vs 11.3%) using Bacillus megaterium DSM 2894 strain under different five mono calcium phosphate (CSP) levels [(69(CSP20); 138(CSP40); 207 (CSP60); 276 (CSP80) and 345 ((CSP100) kg ha-1 of calcium superphosphate (CSP)] to arise the potential efficiency of some nutrients uptake and decease the applied total amount of CSP in 2019 and 2020 seasons. The results mentioned that highest values were obtained by inoculated plants with DSM2894 strain under 20, 60 and 100% of CSP for all studied nutrients content in both seasons, except Mn content in the 2019. Also, inoculated plants with DSM2894 under previous treatments for all tuberous root nutrients content, except Fe and Zn contents in both seasons, in addition protein and anti-radical power and total yield. Statistically, leaf nutrients uptake and tuberous root content were highly significant affected by DSM and CSP combination. Appling of phosphorus fertilizer with DSM2894 mixture was gave the best values as compared with phosphorus fertilizer or DSM2894, individually.
ARTICLE | doi:10.20944/preprints201809.0220.v1
Subject: Biology, Forestry Keywords: sequential chemical extraction; 31P-nuclear magnetic resonance spectroscopy (31P-NMR); phosphorus; coastal sand dune; Casuarina forests
Online: 12 September 2018 (12:35:31 CEST)
Continuous research into the availability of phosphorus (P) in forest soil is critical for sustainable management of forest ecosystems. In this study, we used sequential chemical extraction and 31P-nuclear magnetic resonance spectroscopy (31P-NMR) to evaluate the form and distribution of inorganic P (Pi) and organic P (Po) in Casuarina forest soils of a subtropical coastal sand dune at Houlong in Taiwan. The soil samples were collected from humic (+2-0 cm) and mineral layers (mineral-I: 0-10, mineral-II: 10-20 cm) at two topographic locations (upland and lowland) by elevation. Sequential chemical extraction revealed that the NaOH-Po fraction, as moderately recalcitrant P, was the dominant form in humic and mineral-I layers in both upland and lowland soils, whereas the cHCl-Pi fraction was the dominant form in the mineral-II layer. Resistant P content, including NaOH-Pi, HCl-Pi, cHCl-Pi, and cHCl-Po fractions, was higher in the upland than lowland in the corresponding layers; however, labile P content, NaHCO3-Po, showed the opposite pattern. Content of resistant Pi (NaOH-Pi, HCl-Pi, and cHCl-Pi) increased significantly with depth, but that of labile Pi (resin-Pi and NaHCO3-Pi) and recalcitrant Po (NaHCO3-Po, NaOH-Po, and cHCl-Po) decreased significantly with depth at both locations. 31P-NMR spectroscopy revealed inorganic orthophosphate and monoesters-P as the major forms in this area. The proportions of Pi and Po evaluated by sequential chemical extraction and 31P-NMR spectroscopy were basically consistent. The results indicated that the soils were in weathered conditions. Furthermore, the P distribution and forms significantly differed between the upland and lowland by variation in elevation and eolian aggradation effects in this coastal sand dune landscape.
ARTICLE | doi:10.20944/preprints202110.0126.v1
Subject: Earth Sciences, Environmental Sciences Keywords: Cumulative effects; fine sediment; particulate phosphorus; sediment geochemistry; gravel-bed rivers; forest disturbance; wildfire; eutrophication; climate change
Online: 8 October 2021 (08:07:28 CEST)
Cumulative effects of landscape disturbance in forested source water regions can alter the storage of fine sediment and associated phosphorus in riverbeds, shift nutrient dynamics and degrade water quality. Here, we examine longitudinal changes in major element chemistry and particulate phosphorus (PP) fractions of river-bed sediment in an oligotrophic river during environmentally sensitive low flow conditions. Study sites along 50 km of the Crowsnest River were located below tributary inflows from sub-watersheds and represent a gradient of increasing cumulative sedi-ment pressures across a range of land disturbance types (harvesting, wildfire, and municipal wastewater discharges). Major elements (Si2O, Al2O3, Fe2O3, MnO, CaO, MgO, Na2O, K2O, Ti2O, V2O5, P2O5), loss on ignition (LOI), PP fractions (NH4CI-RP, BD-RP, NaOH-RP, HCI-RP and NaOH(85)-RP) and absolute particle size were evaluated for sediments collected in 2016 and 2017. While total PP concentrations were similar across all sites, bioavailable PP fractions (BD-RP, NaOH-RP) increased downstream with increased concentrations of Al2O3 and MnO and levels of landscape disturbance. This study highlights the longitudinal water quality impacts of increasing landscape disturbance on bioavailable PP in fine riverbed sediments and shows how the convergence of climate (wildfire) and anthropogenic (sewage effluent, harvesting, agriculture) drivers can produce legacy effects on nutrients.
ARTICLE | doi:10.20944/preprints202012.0001.v1
Subject: Life Sciences, Biochemistry Keywords: Mungbean; low phosphorus; drought stress; organic acid exudation; photosynthetic rate; relative water content; membrane stability index; stress susceptibility index; principal component analysis ranking
Online: 1 December 2020 (08:05:27 CET)
To understand the physiological basis of tolerance to combined stresses to low phosphorus (P) and drought in mungbean (Vigna radiata (L.) R. Wilczek), a core set of 100 accessions were evaluated in hydroponics at sufficient (250 μM) and low (3 μM) P, and exposed to drought (dehydration) stress. The principal component analysis and ranking of accessions based on relative values revealed that IC280489, EC397142, IC76415, IC333090, IC507340 and IC121316 performed superior while IC119005, IC73401, IC488526 and IC325853 performed poorly in all treatments. Selected accessions were evaluated in soil under control (sufficient P, irrigated), low P (without P, irrigated), drought (sufficient P, withholding irrigation) and combined stress (low P, withholding irrigation). Under combined stress, a significant reduction in gas exchange traits (photosynthesis, stomatal conductance, transpiration, instantaneous water use efficiency), P uptake in seed and shoot was observed under combined stress as compared to individual stresses. Among accessions, IC488526 was most sensitive while IC333090 and IC507340 exhibited tolerance to individual or combined stress. The water balance and low P adaptation traits like membrane stability index, relative water content, specific leaf weight, organic acid exudation, biomass, grain yield and P uptake can be used as physiological markers to evaluate for agronomic performance. Accessions with considerable resilience to low P and drought stress can be either used as ‘donors’ in Vigna breeding program or cultivated in areas with limited P and water availability or both.