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Nature Jan 2017The macronutrient phosphorus is thought to limit primary productivity in the oceans on geological timescales. Although there has been a sustained effort to reconstruct...
The macronutrient phosphorus is thought to limit primary productivity in the oceans on geological timescales. Although there has been a sustained effort to reconstruct the dynamics of the phosphorus cycle over the past 3.5 billion years, it remains uncertain whether phosphorus limitation persisted throughout Earth's history and therefore whether the phosphorus cycle has consistently modulated biospheric productivity and ocean-atmosphere oxygen levels over time. Here we present a compilation of phosphorus abundances in marine sedimentary rocks spanning the past 3.5 billion years. We find evidence for relatively low authigenic phosphorus burial in shallow marine environments until about 800 to 700 million years ago. Our interpretation of the database leads us to propose that limited marginal phosphorus burial before that time was linked to phosphorus biolimitation, resulting in elemental stoichiometries in primary producers that diverged strongly from the Redfield ratio (the atomic ratio of carbon, nitrogen and phosphorus found in phytoplankton). We place our phosphorus record in a quantitative biogeochemical model framework and find that a combination of enhanced phosphorus scavenging in anoxic, iron-rich oceans and a nutrient-based bistability in atmospheric oxygen levels could have resulted in a stable low-oxygen world. The combination of these factors may explain the protracted oxygenation of Earth's surface over the last 3.5 billion years of Earth history. However, our analysis also suggests that a fundamental shift in the phosphorus cycle may have occurred during the late Proterozoic eon (between 800 and 635 million years ago), coincident with a previously inferred shift in marine redox states, severe perturbations to Earth's climate system, and the emergence of animals.
Topics: Animals; Atmosphere; Biological Evolution; Carbon; Earth, Planet; Geologic Sediments; History, Ancient; Iron; Nitrogen; Oxidation-Reduction; Oxygen; Phosphorus; Seawater
PubMed: 28002400
DOI: 10.1038/nature20772 -
Environmental Science & Technology Aug 2023Excess phosphorus (P) is a major pollutant in aquatic systems. Phosphorus removal structures, landscape-scale filters designed to capture dissolved P from runoff,...
Excess phosphorus (P) is a major pollutant in aquatic systems. Phosphorus removal structures, landscape-scale filters designed to capture dissolved P from runoff, drainage, and wastewater offer promise in curbing P pollution. While the environmental benefits of various P removal structures are well documented, the cost-effectiveness of each structure's ability to sequester P is lacking. In this study, we compare the cost-effectiveness of P removal of the most prominent P removal structures. Specifically, we calculate the average cost per kilogram (kg) of P removed by eight different P removal structures across a range of parameter assumptions. Absent constraints, we found that (1) larger structures that use (2) regionally available phosphorus sorption materials that are (3) byproducts of industrial production (e.g., metal shavings and steel slag) rather than manufactured are more cost-effective. The average cost of P removal for most structures varies from $100 to 1300 per kg in our baseline estimations, which is comparable to the average cost for wastewater treatment. This work provides further information to guide the optimal implementation of P removal structures for conservationists.
Topics: Phosphorus; Wastewater; Environmental Pollutants; Water Purification; Steel
PubMed: 37581469
DOI: 10.1021/acs.est.3c02696 -
The Science of the Total Environment Nov 2022Eutrophication continues to be a concerning global water quality issue. Managing and mitigating harmful algal blooms demands clear information on the conditions...
Eutrophication continues to be a concerning global water quality issue. Managing and mitigating harmful algal blooms demands clear information on the conditions promoting large phosphorus losses from contributing watersheds. Of particular concern is the amount and form of phosphorus loading to receiving water bodies during extreme runoff events, which are expected to increase in frequency due to climate change. Five years (2015 to 2020) of water quantity and quality data from 11 agricultural watersheds in the lower Great Lakes basin were analyzed and used to model total and dissolved phosphorus losses. This study aimed to assess temporal dynamics in phosphorus concentrations and losses over runoff events covering a wide range of hydrologic conditions and to quantify their relative importance on annual phosphorus losses. Event concentration-discharge relationships for total and dissolved phosphorus were hysteretic and had contrasting dominant patterns across watersheds. The proportion of annual phosphorus losses during events was highly variable between watersheds, accounting for 47-94 %. Extreme events were particularly impactful: as few as three events per year were found to be responsible for nearly half of total phosphorus (20-50 %) and total dissolved phosphorus (14-44 %) losses. Variability in total and dissolved phosphorus losses and concentrations over a wide range of flow conditions suggests that event magnitude is an important control on the relative mobility of particulate and dissolved phosphorus fractions. This study showed that insights into nutrient dynamics and phosphorus budgets in the lower Great Lakes basin and agriculture dominated environments more broadly can be gained by assessing event nutrient losses with respect to flow conditions and patterns in concentration-discharge relationships.
Topics: Agriculture; Environmental Monitoring; Eutrophication; Phosphorus; Rivers
PubMed: 35926630
DOI: 10.1016/j.scitotenv.2022.157736 -
Journal of the American Chemical Society Sep 2022Appetite for reactions involving PH has grown in the past few years. This in part is due to the ability to generate PH cleanly and safely via digestion of cheap metal... (Review)
Review
Appetite for reactions involving PH has grown in the past few years. This in part is due to the ability to generate PH cleanly and safely via digestion of cheap metal phosphides with acids, thus avoiding pressurized cylinders and specialized equipment. In this perspective we highlight current trends in forming new P-C/P-OC bonds with PH and discuss the challenges involved with selectivity and product separation encumbering these reactions. We highlight the reactivity of PH with main group reagents, building on the early pioneering work with transition metal complexes and PH. Additionally, we highlight the recent renewal of interest in alkali metal sources of HP which are proving to be useful synthons for chemistry across the periodic table. Such MPH sources are being used to generate the desired products in a more controlled fashion and are allowing access to unexplored phosphorus-containing species.
Topics: Coordination Complexes; Metals; Phosphorus; Transition Elements
PubMed: 36070395
DOI: 10.1021/jacs.2c07688 -
Philosophical Transactions of the Royal... Sep 2017Phosphorus is an essential element for life, serving as an integral component of nucleic acids, lipids and a diverse range of other metabolites. Concentrations of... (Review)
Review
Phosphorus is an essential element for life, serving as an integral component of nucleic acids, lipids and a diverse range of other metabolites. Concentrations of bioavailable phosphorus are low in many aquatic environments. Microalgae, including diatoms, apply physiological and molecular strategies such as phosphorus scavenging or recycling as well as adjusting cell growth in order to adapt to limiting phosphorus concentrations. Such strategies also involve adjustments of the carbon metabolism. Here, we review the effect of phosphorus limitation on carbon metabolism in diatoms. Two transcriptome studies are analysed in detail, supplemented by other transcriptome, proteome and metabolite data, to gain an overview of different pathways and their responses. Phosphorus, nitrogen and silicon limitation responses are compared, and similarities and differences discussed. We use the current knowledge to propose a suggestive model for the carbon flow in phosphorus-replete and phosphorus-limited diatom cells.This article is part of the themed issue 'The peculiar carbon metabolism in diatoms'.
Topics: Carbon; Diatoms; Phosphorus
PubMed: 28717016
DOI: 10.1098/rstb.2016.0406 -
Marine Pollution Bulletin May 2022This study has been carried out to understand the geochemistry of elements namely, iron (Fe) and phosphorus (P) in the core sediments of an urbanized tropical mangrove...
This study has been carried out to understand the geochemistry of elements namely, iron (Fe) and phosphorus (P) in the core sediments of an urbanized tropical mangrove ecosystem along the Southwest coast of India. The study revealed the coupling of iron and phosphorus in which the reductive conditions induced reductive dissolution and upward transport of Fe, causing surface coprecipitation of phosphorus incorporated Fe oxyhydroxides. The accumulation and transformation of phosphorus were significantly influenced by processes viz., phosphorus regeneration due to organic matter mineralization and adsorption to inorganic iron oxides/Ca bound minerals in the surface sediments, and phosphorus retention in the sedimentary column by transformation into refractory organic phosphates. Bioavailable phosphorus (BAP) accounted for more than 50% of TP, so that the mangrove sediments act as an important internal nutrient source of iron and phosphorus for coastal eutrophication.
Topics: Ecosystem; Eutrophication; Geologic Sediments; Iron; Phosphorus
PubMed: 35413502
DOI: 10.1016/j.marpolbul.2022.113636 -
Science (New York, N.Y.) Jun 2022A key building block enables a general synthesis of chiral phosphorus drugs.
A key building block enables a general synthesis of chiral phosphorus drugs.
Topics: Pharmaceutical Preparations; Phosphorus; Phosphorus Compounds; Stereoisomerism
PubMed: 35679417
DOI: 10.1126/science.abq5073 -
Journal of Animal Physiology and Animal... Apr 2018To investigate the relationship between faecal calcium (Ca) and phosphorus (P) excretion in different mammalian species, a meta-analysis on digestibility data derived... (Meta-Analysis)
Meta-Analysis Review
To investigate the relationship between faecal calcium (Ca) and phosphorus (P) excretion in different mammalian species, a meta-analysis on digestibility data derived from the literature was conducted. Seventy-three studies on carnivores, omnivores, large and small hindgut fermenters, ruminants and hippos (a total of 21 mammalian species, precondition for inclusion dietary Ca/P ratio 1.5/1 - 3.0/1) were analysed for Ca and P digestibility. Dietary Ca/P ratios were lower than faecal Ca/P ratios in carnivores, omnivores, ruminants and hippos. In hindgut fermenters, dietary Ca/P ratios were higher than faecal Ca/P ratios, indicating higher intestinal Ca absorption in these species. In all species investigated, there was a significant positive relationship between Ca intake and faecal Ca excretion and between P intake and faecal P excretion. In the biologically relevant range, these equations predicted lower faecal Ca losses in hindgut fermenters than ruminants, for faecal P vice versa. In all species, faecal Ca and P excretion correlated significantly. In carnivores, this highly linear correlation was exceptionally strong (R² = .92). Yet, the linearity of the correlation was questionable in omnivores and ruminants. Possibly, the strong linear correlation of faecal Ca and P excretion in carnivores is due to the formation of insoluble Ca/P complexes in their relatively short and simple gastrointestinal tract. Another hypothesis is that in carnivores, Ca homeostasis relies on modifying bone turnover to a higher degree than on changes in intestinal Ca absorption. For the formation of bone matrix, a constant ratio of Ca and P absorption is of advantage.
Topics: Animals; Calcium; Digestion; Feces; Mammals; Phosphorus
PubMed: 29178376
DOI: 10.1111/jpn.12844 -
Advanced Drug Delivery Reviews Sep 2022Two-dimensional (2D) materials such as the graphene-based materials, transition metal dichalcogenides, transition metal carbides and nitrides (MXenes), black phosphorus,... (Review)
Review
Two-dimensional (2D) materials such as the graphene-based materials, transition metal dichalcogenides, transition metal carbides and nitrides (MXenes), black phosphorus, hexagonal boron nitride, and others have attracted considerable attention due to their unique physicochemical properties. This is true not least in the field of medicine. Understanding the interactions between 2D materials and the immune system is therefore of paramount importance. Furthermore, emerging evidence suggests that 2D materials may interact with microorganisms - pathogens as well as commensal bacteria that dwell in and on our body. We discuss the interplay between 2D materials, the immune system, and the microbial world in order to bring a systems perspective to bear on the biological interactions of 2D materials. The use of 2D materials as vectors for drug delivery and as immune adjuvants in tumor vaccines, and 2D materials to counteract inflammation and promote tissue regeneration, are explored. The bio-corona formation on and biodegradation of 2D materials, and the reciprocal interactions between 2D materials and microorganisms, are also highlighted. Finally, we consider the future challenges pertaining to the biomedical applications of various classes of 2D materials.
Topics: Graphite; Humans; Immune System; Phosphorus
PubMed: 35810883
DOI: 10.1016/j.addr.2022.114422 -
Advanced Healthcare Materials Jan 2023As a functional 2D material, black phosphorus (BP) has garnered wide attention from many researchers in recent years. BP has a wide NIR absorption window and is a...
As a functional 2D material, black phosphorus (BP) has garnered wide attention from many researchers in recent years. BP has a wide NIR absorption window and is a promising candidate for cancer phototherapy including photothermal therapy (PTT) and photodynamic therapy (PDT). However, due to its rapid degradation and short shelf-life in conventional water, the application of BP in the field of cancer therapy is limited. Violet phosphorus (VP), the more stable allotrope of phosphorus, has not yet been investigated for its function and biological application. In this study, VP nanosheets are successfully fabricated by liquid-phase exfoliation and demonstrated that their shelf-life in deionized water could be as long as 10 days, which is much longer than that of BP. Through in vivo and in vitro experiments, the PDT, PTT, and catalytic therapeutic effects of VP, as well as its excellent biosafety for the first time are shown. VP effectively inhibits tumor growth without causing major side effects. The current study provides new ideas and strategies for the biological application of 2D sheets of phosphorus isotope and lays the foundation for further studies on exploring the biomedical application of phosphorus isotopes.
Topics: Humans; Phosphorus; Photochemotherapy; Phototherapy; Neoplasms; Cell Line, Tumor
PubMed: 36285829
DOI: 10.1002/adhm.202201995