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Aims: Global environmental changes are known to affect terrestrial ecosystems functions (i.e., plant growth and carbon storage). However, how plants and soil microorganisms respond to warming and nitrogen deposition in dry ecosystems with strong seasonal precipitation remains largely unexplored. Methods: Based on a 13-year manipulative field experiment, we investigated the effects of warming and nitrogen addition on soil microbial communities and plant net photosynthetic rates during dry and wet months in a desert steppe in Inner Mongolia. Results: We found that in the wet month, warming and nitrogen addition significantly increased soil microbial biomass. Yet, warming and nitrogen addition significantly increased soil inorganic nitrogen and leaf nitrogen concentration, thus promoting an increase in the net photosynthetic rate of Stipa breviflora. Moreover, warming and nitrogen addition significantly shifted soil microbial composition with an increase in soil bacterial phospholipid fatty acids (PLFAs) but a reduction in fungal PLFAs. The increased soil inorganic nitrogen indirectly enhanced leaf nitrogen and plant photosynthesis by changing soil microbial community structure. These changes were not significant in the dry month. Conclusions: Our study indicates that warming and nitrogen addition can promote plant photosynthesis by increasing soil nitrogen availability and changing soil microbial community structure. These changes only occurred when there was sufficient precipitation. These results highlight the crucial role of the soil microbial community and precipitation availability in influencing plant growth responses to global change drivers such as warming and nitrogen deposition. These findings suggest the importance of manipulating multiple factors rather than single factors in global change experiments and the role of plant and soil microbial interactions in ecosystem functions (i.e., plant growth and carbon storage) under global change. [ABSTRACT FROM AUTHOR]

The plant microbes are an integral part of the host and play fundamental roles in plant growth and health. There is evidence indicating that plants have the ability to attract beneficial microorganisms through their roots in order to defend against pathogens. However, the mechanisms of plant microbial community assembly from below- to aboveground compartments under pathogen infection remain unclear. In this study, we investigated the bacterial and fungal communities in bulk soil, rhizosphere soil, root, stem, and leaf of both healthy and infected (Potato virus Y disease, PVY) plants. The results indicated that bacterial and fungal communities showed different recruitment strategies in plant organs. The number and abundance of shared bacterial ASVs between bulk and rhizosphere soils decreased with ascending migration from below- to aboveground compartments, while the number and abundance of fungal ASVs showed no obvious changes. Field type, plant compartments, and PVY infection all affected the diversity and structures of microbial community, with stronger effects observed in the bacterial community than the fungal community. Furthermore, PVY infection, rhizosphere soil pH, and water content (WC) contributed more to the assembly of the bacterial community than the fungal community. The analysis of microbial networks revealed that the bacterial communities were more sensitive to PVY infection than the fungal communities, as evidenced by the lower network stability of the bacterial community, which was characterized by a higher proportion of positive edges. PVY infection further increased the bacterial network stability and decreased the fungal network stability. These findings advance our understanding of how microbes respond to pathogen infections and provide a rationale and theoretical basis for biocontrol technology in promoting sustainable agriculture. Key points: • Different recruitment strategies between plant bacterial and fungal communities. • Bacterial community was more sensitive to PVY infection than fungal community. • pH and WC drove the microbial community assembly under PVY infection. [ABSTRACT FROM AUTHOR]

The contact between metal oxide nanoparticles (NPs) and human is more and more close with their wide applications. The inputs of metal oxide NPs to the environment are also growing every year, which causes potential environmental and human health risks. They are toxic to animals, microorganisms and plants at high concentrations, and they show different mechanisms of toxicity to different species. In addition, under complex environmental conditions, their toxic effects are often unpredictable. We have integrated the recent studies on the biotoxicity of metal oxide NPs from 2015-present, and clarified their toxic mechanism, as well as the toxic harm. It lays a foundation for further studying the toxicity and ecological risk of metal oxide NPs. • Metal oxide NPs can inhibit plant growth and affect the photosynthesis. • Metal oxide NPs in animals can lead to organs' damage and cytotoxicity. • The microbial community can be changed by metal oxide NPs. [ABSTRACT FROM AUTHOR]

Abstract Carbon nanomaterials (CNMs) are widely used because of their unique advantages in recent years. At the same time, the influence of CNMs on the environment is becoming increasingly prominent. This review mainly introduces the research progress in the effects of fullerenes, multi-walled carbon nanotubes (MWCNTs), single-walled carbon nanotubes (SWCNTs) and graphene on microorganisms and their toxicity mechanisms. On this basis, we have analyzed beneficial and adverse effects of fullerenes, graphene, MWCNTs and SWCNTs to microorganisms, and discussed the similarities of the toxicity mechanisms of different CNMs on microorganisms. This review helps provide ideas on how to protect microorganisms from the impacts of carbon nanomaterials, and it will be conductive to providing a strong theoretical basis for better application of carbon nanomaterials. Highlights • Fullerenes are less toxic to microorganisms than other CNMs and can disrupt the electrostatic balance of microbial cells. • SWCNT is more toxic to microorganisms than MWCNT, both of them destroy microbial cell by breaking cell wall or membrane. • Graphene can cause changes in the number of microorganisms and community structure. [ABSTRACT FROM AUTHOR]

Bacteria, archaea and fungi usually coexist in various soil habitats and play important roles in biogeochemical cycle and remediation of contamination. Despite their significance, their combined bioassembly pattern, ecological interactions and driving factors in contaminated soils still remain obscure. To fill the gap, a systemic investigation on the characteristics of microbial community including bacteria, archaea and fungi, assembly patterns and environmental driving factors was conducted in an abandoned gas station soils which were contaminated by polycyclic aromatic compounds and potentially toxic elements for decades. The results showed that the soils were contaminated excessively by benzo[a]pyrene (0.46–2.00 mg/kg) and Dibenz[a,h]anthracene (0.37–1.30 mg/kg). Multitudinous contaminant-degrading/resistant microorganisms and unigenes were detected, indicating potential of the soils to mitigate the pollution. Compared with fungi and archaea, the bacteria had higher community diversity and were more responsive to seasonal shifts. Functional genes (nidB , nahAb , nahAa , adhP , adh , adhC , etc.) involved in biodegradation were highly enriched in summer (1.96% vs 1.80%). The co-occurrence network analysis showed summer communities exhibit a more robust network structure and positive interactions than winter communities. The fungi Neocucurbitaria , Penicillium , Fusarium , Chrysosporium , Knufia , Filobasidium , Wallemia and Rhodotorula were identified as the keystone taxa, indicating that fungi also had important positions in the interdomain molecular ecological networks of both seasons. The network topological properties and |βNTI| (66.7%–93.3% greater than 2) results indicated the deterministic assembly processes of the microbial communities in the contaminated soil. Acenaphthylene, benzo[b]fluoranthene, indeno[1,2,3-cd]perylene, benzo[g,h,i]pyrene and 9-fluorenone were the key environmental factors driving the deterministic assembly processes of the interdomain microbial community in the contaminated soil. These findings extended our knowledge of interdomain microbial community assembly mechanisms and ecological patterns in natural attenuation and provide valuable guidance in associated bioremediation strategies. • PAH contamination affected bacterial diversity more than fungi and archaea 3 diversity. • Fungi were keystone species in the interdomain ecological networks. • Summer was more conducive to the stability and dynamics of microorganisms. • PAHs and their derivatives drove the interdomain microbial community assembly. [ABSTRACT FROM AUTHOR]

Soil polycyclic aromatic compound (PAC) pollution as a result of petroleum exploitation has caused serious environmental problems. The unclear assembly and functional patterns of microorganisms in oilfield soils limits the understanding of microbial mechanisms for PAC elimination and health risk reduction. This study investigated the polycyclic aromatic hydrocarbons (PAHs) and substituted PAHs (SPAHs) occurrence, and their impact on the bacteria-archaea-fungi community diversity, co-occurrence network and functionality in the soil of an abandoned oilfield. The results showed that the PAC content in the oilfield ranged from 3429.03 μg kg−1 to 6070.89 μg kg−1, and risk assessment results suggested a potential cancer risk to children and adults. High molecular weight PAHs (98.9%) and SPAHs (1.0%) contributed to 99.9% of the toxic equivalent concentration. For microbial analysis, the abundantly detected degraders and unigenes indicated the microbial potential to mitigate pollutants and reduce health risks. Microbial abundance and diversity were found to be negatively correlated with health risk. The co-occurrence network analysis revealed nonrandom assembly patterns of the interdomain microbial communities, and species in the network exhibited strong positive connections (59%). The network demonstrated strong ecological linkages and was divided into five smaller coherent modules, in which the functional microbes were mainly involved in organic substance and mineral component degradation, biological electron transfer and nutrient cycle processes. The keystone species for maintaining microbial ecological functions included Marinobacter of bacteria and Neocosmospora of fungi. Additionally, benzo [g,h,i]pyrene, dibenz [a,h]anthracene, indeno [1,2,3-cd]perylene and total phosphorus were the key environmental factors driving the assembly and functional patterns of microbial communities under pollution stress. This work improves the knowledge of the functional pattern and environmental adaptation mechanisms of interdomain microbes, and provides valuable guidance for the further bioremediation of PAC-contaminated soils in oilfields. [Display omitted] • HMW PAH and SPAH contributed most to the TEQBaP and health risk. •Mass degraders and unigenes and high abundance and diversity indicated low risk. •Interdomain networks show robust connectivity and complexity. •Specialized but interdependent ecological clusters facilitated PAC elimination. •Key environmental drivers of microbial communities were DahA, IncdP, BghiP and TP. [ABSTRACT FROM AUTHOR]