Publications

Arbuscular mycorrhizal fungi (AMF) form symbioses with most plants, potentially improving their growth and nutrient assimilation activities. Cysteine (Cys) and methionine (Met) are nitrogen (N)- and sulphur (S)-containing amino acids. Compared with phosphate and N, limited attention has been paid to the role of AMF in low molecular weight organic S acquisition. To explore the uptake and relative contributions of organic and inorganic N and S to plants, and the role of AMF in S uptake, a pot study was conducted based on 14C, 35S, 13C, and 15N quad labelling (6-h labelling test after adding the labelled solution to the soil–plant system) using a mutant tomato genotype with highly decreased AMF symbiosis capacity. Tomato roots can uptake limited amounts of added Met and Cys (<1.77%) within 6 h, as indicated by the 14C and 13C labelling results, and most of them were utilised by soil microorganisms. After uptake for 6 h, 10.0–14.8% of N and 1.4–6.1% of S derived from added Cys and Met were utilised by plants, mainly in inorganic N and S forms derived from Cys and Met decomposition. Met and Cys could be important S sources (Met: 3.0–9.8%, Cys: 8.8–22.0%) for plants, however have negligible roles in N nutrition (∼1%), as most N uptake by plants was derived from soil inorganic N. The tomato uptake of inorganic S derived from Cys decomposition was much higher than that derived from Met, as higher ratios of S-Cys were released as SO4 2− from microorganisms during the 6-h testing periods. Even with the artificial addition of AMF, most of the added Met and Cys were utilised by Gram-negative bacteria, as indicated by 13C-PLFA biomarkers. AMF reduced host plant uptake of organic N and S, but stimulated plant N uptake from Met and Cys, which was mainly inorganic N following mineralisation. AMF not only utilise organic carbon from host plants but also capture soil organic matter to satisfy their energy demands. In the spaces where both root and AMF occur, AMF colonisation decreased tomato 35S uptake from Cys, Met, and SO4 2− by 24.6%, 20.6%, and 11.0% within the 6-h uptake period, respectively, when compared with that in the mutant genotype with reduced colonisation capacity; in contrast, AMF colonisation increased 35S-Cys uptake by 118.7% from areas that roots could not reach. Overall, AMF enhanced host plant N uptake but reduced organic N uptake under competition with plant roots for S in the rhizosphere, but stimulated plant S uptake by extraradical mycelia, based on this short-term pulse-chase test.

Phosphorus (P) deficiency limits crop yields globally, creating a need for sustainable alternatives to synthetic P fertilizers. This study evaluates the effects of biochar and bone char on maize growth, soil fertility, P availability, and greenhouse gas (GHG) emissions in soils with a moderate or low P content. A 42-day pot experiment was conducted with three treatments: control, conventional biochar, and bone char, each applied at 1% (w/w). Measurements included plant growth, soil properties, nutrient levels in soil and pore water, and GHG fluxes (N 2 O, CH 4 and CO 2 ). The results showed that bone char significantly enhanced plant growth, especially in P-deficient soils, where shoot biomass was ten times higher than the control. Bone char also dramatically increased P availability in both soil types, outperforming biochar, which had limited effects on P levels. In terms of GHG mitigation, both biochar and bone char reduced N 2 O and CH 4 emissions compared to the control, with bone char showing greater effectiveness in P-deficient soils, potentially due to its slow-release nutrient properties. Biochar promoted methane consumption, especially in P-rich soils. The findings suggest that bone char is an ideal amendment for P-deficient soils, offering dual benefits of nutrient enhancement and GHG reduction, while biochar's advantages lie in improving soil physical properties and mitigating emissions across different soil types. Overall, we conclude that bone char represents a viable option to improve sustainable P cycling and GHG mitigation in agronomic systems, highlighting the circular economy benefits of repurposing waste materials. • Bone char increased P availability and plant growth in P-deficient soils • Bone char and biochar reduced greenhouse gas emissions, particularly in low-P soil • Biochar improved soil physical properties, bone char enhanced nutrient cycling • Bone char increased shoot biomass tenfold compared to control in the low P soil • Bone char offers dual benefits: sustainable P source and greenhouse gas mitigation

Correction for ‘Microbial degradation of bioplastic (PHBV) is limited by nutrient availability at high microplastic loadings’ by Michaela K. Reay et al. , Environ. Sci.: Adv. , 2025, 4 , 133–146, https://doi.org/10.1039/D4VA00311J.

This manuscript showcases results from a large scale and comprehensive wastewater-based epidemiology (WBE) study focussed on multi-biomarker suite analysis of both chemical and biological determinants in 10 cities and towns across England equating to a population of ∼7 million people. Multi-biomarker suite analysis, describing city metabolism, can provide a holistic understanding to encompass all of human, and human-derived, activities of a city in a single model: from lifestyle choices (e.g. caffeine intake, nicotine) through to health status (e.g. prevalence of pathogenic organisms, usage of pharmaceuticals as proxy for non-communicable disease, NCD, conditions or infectious disease status), and exposure to harmful chemicals due to environmental and industrial sources (e.g. pesticide intake via contaminated food and industrial exposure). Population normalised daily loads (PNDLs) of many chemical markers were found, to a large extent, driven by the size of population contributing to wastewater (especially NCDs). However, there are several exceptions providing insights into chemical intake that can inform either disease status in various communities or unintentional exposure to hazardous chemicals: e.g. very high PNDLs of ibuprofen in Hull resulting from its direct disposal (confirmed by ibuprofen/2-hydroxyibuprofen ratios) and bisphenol A (BPA) in Hull, Lancaster and Portsmouth likely related to industrial discharge. An importance for tracking endogenous health markers such as 4-hydroxy-2-nonenal-mercapturic acid (HNE-MA, an oxidative stress marker) as a generic marker of health status in communities was observed due to increased levels of HNE-MA seen at Barnoldswick wastewater treatment plant that coincided with higher-than-average paracetamol usage and SARS-CoV-2 prevalence in this community. PNDLs of virus markers were found to be highly variable. Being very prevalent in communities nationwide during sampling, SARS-CoV-2 presence in wastewater was to a large extent community driven. The same applies to the fecal marker virus, crAssphage, which is very prevalent in urban communities. In contrast, norovirus and enterovirus showed much higher variability in prevalence across all sites investigated, with clear cases of localized outbreaks in some cities while maintaining low prevalence in other locations. In conclusion, this study clearly demonstrates the potential for WBE to provide an integrated assessment of community health which can help target and validate policy interventions aimed at improving public health and wellbeing.

No abstract is provided for this article.

A study was conducted under greenhouse conditions on wheat to investigate the utilization of dissolved organic nitrogen (N) in comparison with conventionally applied inorganic N sources (INS). Nitrogen was applied at a rate of 90 kg N ha−1 in an inorganic form, an organic high molecular weight (MW) form (casein, haemoglobin, albumin), and an organic low MW amino acid form (glycine, alanine, valine). Inorganic N sources recorded the maximum response (126% to 150%) in total dry matter (DM) production while dissolved organic nitrogen (DON) sources showed 61% to 116% increase in comparison to the control treatment. Glycine gave the maximum DM production, which was comparable with both INS treatments. In hydroponics, greater utilization occurred and the shoots had a higher N content in comparison to those grown in soil. The concentration of DON and NO3− in soil after wheat harvest was similar in all the treatments.Keywords: amino acids dissolved organic nitrogenmineral Nproteinwheat

The effect of grazing by large herbivores on the microbial community and the ecosystem functions they provide are relatively unknown in grassland systems.

Soil biota accounts for ~25% of global biodiversity and is vital to nutrient cycling and primary production. There is growing momentum to study total belowground biodiversity across large ecological scales to understand how habitat and soil properties shape belowground communities. Microbial and animal components of belowground communities follow divergent responses to soil properties and land use intensification; however, it is unclear whether this extends across heterogeneous ecosystems. Here, a national-scale metabarcoding analysis of 436 locations across 7 different temperate ecosystems shows that belowground animal and microbial (bacteria, archaea, fungi, and protists) richness follow divergent trends, whereas β-diversity does not. Animal richness is governed by intensive land use and unaffected by soil properties, while microbial richness was driven by environmental properties across land uses. Our findings demonstrate that established divergent patterns of belowground microbial and animal diversity are consistent across heterogeneous land uses and are detectable using a standardised metabarcoding approach.

Advocates of ‘local food’ claim it serves to reduce food miles and greenhouse gas emissions, improve food safety and quality, strengthen local economies and enhance social capital. We critically review the philosophical and scientific rationale for this assertion, and consider whether conventional scientific approaches can help resolve the debate. We conclude that food miles are a poor indicator of the environmental and ethical impacts of food production. Only through combining spatially explicit life cycle assessment with analysis of social issues can the benefits of local food be assessed. This type of analysis is currently lacking for nearly all food chains.

Maintaining food production for a growing world population without compromising natural resources for future generations represents one of the greatest challenges for agricultural science, even compared with the green revolution in the 20th century. The intensification of agriculture has now reached a critical point whereby the negative impacts derived from this activity are now resulting in irreversible global climate change and loss in many ecosystem services. New approaches to help promote sustainable intensification are therefore required. One potential solution to help in this transition is the use of plant biostimulants based on humic substances. In this review we define humic substances in a horticultural context. Their effects on nutrient uptake and plant metabolism are then discussed and a general schematic model of plant-humic responses is presented. The review also highlights the relationship between the chemical properties of humified matter and its bioactivity with specific reference to the promotion of lateral root growth. Finally, we summarize and critically evaluate experimental data related to the overall effect of humic substances applied to horticultural crops. Current evidence suggests that the biostimulant effects of humic substances are characterized by both structural and physiological changes in roots and shoots related to nutrient uptake, assimilation and distribution (nutrient use efficiency traits). In addition, they can induce shifts in plant primary and secondary metabolism related to abiotic stress tolerance which collectively modulate plant growth as well as promoting fitness. In conclusion, the exogenous application of humic substances within agronomic systems can be used to aid the development of sustainable intensification. As most humic substances used in agriculture are currently derived from non-renewable resources like coal and peat, the promotion of this technology also requires the development of new sustainable sources of humic products (e.g. organic wastes).

This paper presents a comprehensive and critical review of research on different co-composting approaches to bioremediate hydrocarbon contaminated soil, organisms that have been found to degrade PAHs, and PAH breakdown products. Advantages and limitations of using certain groups of organisms and recommended areas of further research effort are identified. Studies investigating the use of composting techniques to treat contaminated soil are broad ranging and differ in many respects, which makes comparison of the different approaches very difficult. Many studies have investigated the use of specific bio-additives in the form of bacteria or fungi with the aim of accelerating contaminant removal; however, few have employed microbial consortia containing organisms from both kingdoms despite knowledge suggesting synergistic relationships exist between them in contaminant removal. Recommendations suggest that further studies should attempt to systemize the investigations of composting approaches to bio-remediate PAH-contaminated soil, to focus on harnessing the biodegradative capacity of both bacteria and fungi to create a cooperative environment for PAH degradation, and to further investigate the array of PAHs that can be lost during the composting process by either leaching or volatilization. KEYWORDS: bio-degradationsoil-pollutionmicro-organismssoil treatment methods ACKNOWLEDGMENTS The funding of this study by the European Social Fund is thankfully acknowledged. Notes ∗ Reviewed by CitationAntizar-Ladislao et al. (2004). † Reviewed by CitationWilson and Jones (1993).