Manure is a potential substitute for chemical phosphate fertilizer, especially in intensive agriculture, such as greenhouse farming, but the associations between soil phosphorus (P) availability and the soil microbial community under manure application instead of chemical phosphate fertilizers are still rarely addressed. In this study, a field experiment in greenhouse farming with manure application instead of chemical phosphate fertilizers was established, including five treatments: a control with conventional fertilization and chemical phosphate fertilizer substitution treatments using manure as the sole P resource at 25% (0.25 Po), 50% (0.50 Po), 75% (0.75 Po), and 100% (1.00 Po) of the control. Except for 1.00 Po, all the treatments applied with manure harbored similar levels of available P (AP) as the control. Most of the bacterial taxa involved in P transformation were enriched in manure treatments. Treatments of 0.25 Po and 0.50 Po significantly enhanced bacterial inorganic P (Pi) dissolution capacity, while 0.25 Po decreased bacterial organic P (Po) mineralization capacity. In contrast, the 0.75 Po and 1.00 Po treatments significantly decreased the bacterial Pi dissolution capacity and increased the Po mineralization capacity. Further analysis revealed that the changes in the bacterial community were significantly correlated with soil pH, total carbon (TC), total nitrogen (TN), and AP. These results revealed the dosage effect of the impact of manure on soil P availability and microbial P transformation capacity and emphasized that an appropriate dosage of organic manure is important in practical production.

Soil biodiversity plays a critical role in supporting multiple ecosystem functions. As some of the most diverse and abundant metazoans on the Earth, soil nematode communities exhibit changes along environmental gradients, but the ways in which the abundance and diversity of nematode communities vary along elevational gradients remain poorly understood. Taking advantage of an investigation on Huangshan Mountain, Southeast China, with elevation ranging from 500 to 1200 m, we assessed the abundance and diversity of soil nematodes, as well as the soil physicochemical properties, across subtropical forest ecosystems. Nematode communities were analyzed at the genus level, and the α-diversity was calculated as the genus richness, while the β-diversity was based on the Bray–Curtis dissimilarity. The results showed that, among the top 20 nematode genera ranked by absolute abundance, most genera, such as Eucephalobus, Prismatolaimus, Filenchus, and Rotylenchulus, reached their peak abundance at the highest elevation (1000 m). Additionally, the abundances of Oriverutus, Tylenchus, Criconema, and Tripyla exhibited a positive correlation with the elevation. Moreover, the abundance and α-diversity of the total nematodes and each trophic group of nematodes increased linearly with the elevation, likely due to increased soil moisture at higher elevation. In contrast, the β-diversity of the total nematodes, bacterivores, and herbivores decreased with increasing elevation, indicating the importance of stochastic processes in shaping community assembly at high altitudes. This pattern suggests that as the elevation increases, the nematode communities become more homogeneous in structure. Taken together, our study’s findings demonstrate the divergent responses of nematodes’ α- and β-diversity to an elevation gradient, highlighting the importance of the soil nematode diversity in maintaining ecosystem functions such as nutrient cycling and food web stability in mountainous regions. These results emphasize the need to incorporate the below-ground biodiversity into conservation strategies, particularly in the face of environmental changes driven by climate and human activities.

Nitrous oxide (N₂O) pulse emissions are detected in soils subjected to freeze–thaw cycles in both laboratory and field experiments. However, the mechanisms underlying this phenomenon are poorly understood. In this study, a laboratory incubation experiment that included freeze–thaw cycles (FTC), freezing (F) and control (CK) treatments was performed on three typical Chinese upland soils, namely, fluvo-aquic soil (FS), black soil (BS) and loess soil (LS). A higher similarity in soil properties and bacterial community structure was discovered between FS and LS than between FS and BS or LS and BS, and the bacterial diversity of FS and LS was higher than that of BS. FTC significantly increased the denitrification potential and the proportion of N₂O in the denitrification gas products in FS and LS but decreased the denitrification potential in BS. Accordingly, with the increasing number of freeze–thaw cycles, the bacterial community composition in the FTC treatments in FS and LS diverged from that in CK but changed little in BS. Taxa that responded to FTC or correlated with denitrification potential were identified. Taken together, our results demonstrated that the effects of FTC on N₂O emissions are soil-type-dependent and that the shift in the microbial community structure may contribute to the elevated N₂O emissions.

Excessive nitrogen (N) fertilization in rice production causes severe environmental consequences, and slow-release N fertilizer and green manure incorporation have been proposed as a sustainable alternative. However, how such integrated practices impact the rhizosphere microbiome and its linkages to plant performance remains poorly understood. In a field experiment with slow-release N fertilizer application, we explored the effects of 20% N reduction (RND) and RND combined with green manure (RNDG) on rhizosphere soil properties, rice growth, and bacterial and fungal communities. Compared with normal N application (RN), RND treatment had negative effects on rice growth, while it can be mitigated by the RNDG treatment. Fungal communities were more sensitive to RND and RNDG treatments than bacterial communities. Specific functional groups, including bacteria involved in N transformation and plant pathogenic fungi, decreased under RND and RNDG treatments. Deterministic processes dominated community assembly for both bacterial and fungal communities; however, the deterministic contribution was strengthened for bacteria under RND and RNDG, whereas it was relaxed for fungi under RND treatment. Correlation analysis revealed that the bacterial community was primarily associated with soil ammonium and nitrate, whereas the fungal community was linked to available phosphorus and plant phosphorus. Overall, integrating green manure with a 20% N reduction effectively compensates for yield loss, enhances bacterial diversity, and reshapes the microbiome toward a more disease-suppressive state. These findings provide a microbial ecological basis for developing green and efficient fertilization strategies in paddy rice systems.

Recent studies implicate that hypertensive disorders of pregnancy (HDP) is associated with gut microbiome. However, the different associations of different microbial features with HDP are little known. This study investigates the different associations of gut bacterial taxonomic composition, functional and network profiles with HDP. A case–control study was conducted in Hefei Maternal and Child Health Hospital from February to August 2024. Twenty-four women with HDP and twenty-one normotensive pregnant controls were included. Fecal samples were collected and the bacterial community in fecal samples were measured using high-throughput sequencing targeting the V4 region of the bacterial 16 S rRNA. The taxonomic composition, functional and network profiles of gut bacterial community in both Control and Case groups were determined, and the associations between HDP and gut bacterial profiles were analyzed. There were no significant differences in gut bacterial community composition between the Control and Case groups. However, the Case group had significantly higher relative abundance of functional taxa associated with intestinal inflammation, primary pathogens involved in gastroenteritis and diarrhea. Furthermore, while the Case group exhibited higher network complexity in gut bacterial interactions, it showed lower ecological variability compared to the Control group. Intriguingly, correlation analyses indicated significantly positive associations between HDP and both microbial functional profiles and species interaction intensity, while no significant correlation was observed with taxonomic composition. Although the gut microbial composition remained unchanged in hypertensive pregnancies, functional dysbiosis characterized by proinflammatory features and altered ecological network properties were significantly associated with pregnant women’s blood pressure. The dissociation between taxonomic profiles and functional profiles, as well as taxon interactions, highlights the importance of microbial function and interactions in the gut microbiome-targeted diagnosis and therapy of HDPs. The online version contains supplementary material available at 10.1186/s12884-025-08117-7.