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Colloidal phosphorus (P), defined as P associated with particles within the size range from 1 to 1000 nm, is an often-neglected yet significant component of waterborne P, posing global water quality concerns. This comprehensive review elucidates the various sources and concentrations of colloidal P across diverse water environments, highlighting its prominence in agricultural wastewater, with mean concentrations of 122.6 μg/L (n = 437), compared to groundwater (52.3 μg/L, n = 26), surface freshwater (22.3 μg/L, n = 246), and seawater (5.4 μg/L, n = 36). Correlations between physicochemical water parameters, elemental composition and colloidal P concentrations are obtained, and the dominant subfractions and chemical species of colloidal P in water are identified. Notably from chemical speciation, colloidal organic P exhibits dominance in surface freshwater with higher abundance relative to colloidal inorganic P. Meanwhile, statistical analyses on physical fractions of colloidal P indicate that fine subfractions prevail in agricultural wastewater. Accordingly, this review investigates potential transformation mechanisms of colloidal P due to physical and chemical behaviors such as aggregation, desorption, and photodegradation, influenced by factors such as pH, salinity, coexisting elements and UV irradiation. Drawing on these insights, we propose eco-friendly mitigation strategies, including constructed wetlands or ecological drainage ditches and UV irradiation, aimed at treating water (especially agricultural wastewater) with elevated colloidal P levels. This review not only enhances our understanding of the occurrence and transformations of colloidal P, but also offers practical guidance for its effective environmental management. [ABSTRACT FROM AUTHOR]

The widespread environmental contamination resulting from the misuse of tetracycline antibiotics (TCs) has garnered significant attention and study by scholars. Photocatalytic technology is one of the environmentally friendly advanced oxidation processes (AOPs) that can effectively solve the problem of residue of TCs in the water environment. This study involved the synthesis of the heterogeneous magnetic photocatalytic material of CoFe2O4/NaBiO3 via the solvothermal method, and it was characterized using different characterization techniques. Then, the photocatalytic system under visible light (Vis) was coupled with peroxymonosulfate (PMS) to explore the performance and mechanism of degradation of tetracycline hydrochloride (TCH) in the wastewater. The characterization results revealed that CoFe2O4/NaBiO3 effectively alleviated the agglomeration phenomenon of CoFe2O4 particles, increased the specific surface area, effectively narrowed the band gap, expanded the visible light absorption spectrum, and inhibited recombination of photogenerated electron–hole pairs. In the Vis+CoFe2O4/NaBiO3+PMS system, CoFe2O4/NaBiO3 effectively activated PMS to produce hydroxyl radicals (·OH) and sulfate radicals (SO4−). Under the conditions of a TCH concentration of 10 mg/L−1, a catalyst concentration of 1 g/L−1 and a PMS concentration of 100 mg/L−1, the degradation efficiency of TCH reached 94% after 100 min illumination. The degradation of TCH was enhanced with the increase in the CoFe2O4/NaBiO3 and PMS dosage. The solution pH and organic matter had a significant impact on TCH degradation. Notably, the TCH degradation efficiency decreased inversely with increasing values of these parameters. The quenching experiments indicated that the free radicals contributing to the Vis+CoFe2O4/NaBiO3+PMS system were ·OH followed by SO4−, hole (h+), and the superoxide radical (O2−). The main mechanism of PMS was based on the cycle of Co3+ and Co2+, as well as Fe3+ and Fe2+. The cyclic tests and characterization by XRD and FT-IR revealed that CoFe2O4/NaBiO3 had good degradation stability. The experimental findings can serve as a reference for the complete removal of antibiotics from wastewater. [ABSTRACT FROM AUTHOR]

Traditional treatment methods for tumors are inefficient and have severe side effects. At present, new therapeutic methods such as phototherapy, chemodynamic therapy, and gasodynamic therapy have been innovatively developed. High concentrations of hydrogen sulfide (H2S) gas exhibit cancer-suppressive effects. Herein, a Prussian blue-loaded tetra-sulfide modified dendritic mesoporous organosilica (PB@DMOS) was rationally constructed with glutathione (GSH)-triggered/photothermal-enhanced H2S signaling molecule release properties for gas therapy. The as-synthesized nanoplatform confined PB nanoparticles in the mesoporous structure of organosilica silica due to electrostatic adsorption. In the case of a GSH overexpressed tumor microenvironment, H2S gas was controllably released. And the temperature increases due to the photothermal effects of PB nanoparticles, further enhancing H2S release. At the same time, PB nanoparticles with excellent hydrogen peroxide catalytic performance also amplified the efficiency of tumor therapy. Thus, a collective nanoplatform with gas therapy/photothermal therapy/catalytic therapy functionalities shows potential promise in terms of efficient tumor therapy. [ABSTRACT FROM AUTHOR]

A global meta-analysis of conservation agriculture principles indicates that the potential contribution of no-till to the sustainable intensification of agriculture is more limited than often assumed. Does conservation agriculture work? Advocates of conservation agriculture, which integrates ecological management (namely zero tillage, permanent soil cover and crop rotation) with modern agricultural production techniques, see it as a means of sustainably increasing global food supply. So far it has proved difficult to establish conclusively whether crop yields are maintained by conservation agriculture and whether it can be applied effectively in widely differing farming contexts. In this meta-analysis of more than 5,000 observations from 610 studies, Cameron Pittelkow and colleagues show that farming using a combination of conservation agriculture techniques can yield as much or more than conventional farming under certain conditions. The use of 'no-till' alone, the central concept of conservation agriculture, negatively impacts yields. But used with the other two conservation agriculture techniques of residue retention and crop rotation, no-till can increase rainfed crop productivity in dry climates, suggesting it may become an important climate-change adaptation strategy. One of the primary challenges of our time is to feed a growing and more demanding world population with reduced external inputs and minimal environmental impacts, all under more variable and extreme climate conditions in the future.sup.1,2,3,4. Conservation agriculture represents a set of three crop management principles that has received strong international support to help address this challenge.sup.5,6, with recent conservation agriculture efforts focusing on smallholder farming systems in sub-Saharan Africa and South Asia.sup.7. However, conservation agriculture is highly debated, with respect to both its effects on crop yields.sup.8,9,10 and its applicability in different farming contexts.sup.7,11,12,13. Here we conduct a global meta-analysis using 5,463 paired yield observations from 610 studies to compare no-till, the original and central concept of conservation agriculture, with conventional tillage practices across 48 crops and 63 countries. Overall, our results show that no-till reduces yields, yet this response is variable and under certain conditions no-till can produce equivalent or greater yields than conventional tillage. Importantly, when no-till is combined with the other two conservation agriculture principles of residue retention and crop rotation, its negative impacts are minimized. Moreover, no-till in combination with the other two principles significantly increases rainfed crop productivity in dry climates, suggesting that it may become an important climate-change adaptation strategy for ever-drier regions of the world. However, any expansion of conservation agriculture should be done with caution in these areas, as implementation of the other two principles is often challenging in resource-poor and vulnerable smallholder farming systems, thereby increasing the likelihood of yield losses rather than gains. Although farming systems are multifunctional, and environmental and socio-economic factors need to be considered.sup.14,15,16, our analysis indicates that the potential contribution of no-till to the sustainable intensification of agriculture is more limited than often assumed., Author(s): Cameron M. Pittelkow [sup.1] [sup.8] , Xinqiang Liang [sup.2] , Bruce A. Linquist [sup.1] , Kees Jan van Groenigen [sup.3] , Juhwan Lee [sup.4] , Mark E. Lundy [sup.1] [...]