Salt-affected soils frequently experience leaching and desalination issues, which severely restrict plant growth and water uptake. Hence, in this experiment, four treatments including CG (no amendments addition); OF (organic fertilizer addition); OH (organic fertilizer and Hekang amendment addition); and OB (organic fertilizer and fulvic acid addition) were designed to examine the effect of organic amendment on soil chemical properties, water and salt transport, and soil desalination laws of coastal saline soil. The results showed that the addition of organic amendments significantly reduced soil pH (8.47–8.52) and salt content (2.06–2.34 g kg⁻¹), while increasing soil organic matter content, available phosphorus, and available potassium. OH treatment has a higher available phosphorus content than other treatments. OH and OB treatments elevated the soil desalination ratio (32.95% and 32.12%, respectively) by raising the leaching volume and leaching rate. Organic amendments significantly promoted Na⁺ (4.5–32%) and SO₄²⁻ (12–27%) leaching compared to CG. Organic treatments, particularly OB treatment, not only increased the content of soil organic matter and available nutrients but also promoted salt ion leaching, improved soil permeability and increased soil desalination and water leaching rates. Our results may provide a theoretical basis for revealing the desalination law of coastal saline soil.

Tidal flats in eastern China have undergone various transformations into other land-use types. Understanding the impact of land-use conversion on soil properties and microbial communities is crucial for effective ecological conservation efforts. In this study, we compared soil chemical properties and the diversity, composition, and ecological functions of soil bacterial and fungal communities across four land-use types: natural bare land (BL), unused reclaimed tidal land (Phragmites, PL), agricultural land (maize, ML), and shelterbelt land (SL), utilizing next-generation sequencing technology. The results indicated that soil electrical conductivity decreased, while soil organic carbon (SOC) and nutrient contents increased in ML and SL compared to BL and PL. The bacterial Chao1 and fungal Chao1 and Shannon values vary across different land-use types. A higher relative abundance of Acidobacteriota, specifically RB41, was found in ML compared to BL. Principal coordinate and PerMANOVA analysis showed that the composition of bacterial and fungal communities differed significantly across the four land-use types. SOC explained the most variance in both bacterial and fungal communities. Carbon-related functional genes and fungal guilds exhibit greater diversity across the four land-use types compared to nitrogen-related functional genes. In conclusion, the transformation of natural land-use types to managed one greatly altered soil chemical and microbial properties. Our study offers foundational insights into the microbial communities in the typical land-use types of Eastern China’s coastal area. Future studies should emphasize the quantification of human interventions and their impact on soil microbial communities and ecological functions.

Soil salinity is an active and complex part of soil property in arid and semiarid irrigation areas that restricts the sustainability of agriculture production. Knowledge of seasonal distributions and migration of soil salinity is important for the management of agriculture. In this study, three-dimensional (3-D) geostatistical methods were used to construct seasonal 3-D spatial distribution maps of soil salinity, and then the quantitative analysis methods were used to study the seasonal accumulation patterns of soil salinity for the 0–150 cm soil depth in cold and semiarid irrigated rice fields. The results revealed that there were different spatial distribution and migration patterns of soil salinity in autumn 2015, spring 2016, autumn 2016, and spring 2017. The migration of soil salinity had a dispersion trend from autumn to spring, and the area of non-saline soil increased. Whereas there was an accumulation trend from spring to autumn, and the area of non-saline soil decreased. There were about 10–20% of the study area had experienced transitional changes of different soil salinity levels in different seasons. The correlation coefficient showed that there were significant positive correlations among the five depth increments (30 cm) in different seasons, and the correlations of soil salinity were higher in adjacent layers than in nonadjacent layers. The EC_e values were higher in the topsoil (0–30 cm) and deeper subsoil (120–150 cm), indicating that soil soluble salts accumulated in the soil surface due to evaporation and accumulated in the bottom due to leaching and drainage. Microtopography was the major factor influencing spatial distribution of soil salinity in different seasons. The EC_e values were generally higher in the swales or in areas with rather poor drainage, whereas the values were lower in relatively higher-lying slopes or that were well-drained. The results provide theoretical basis and reference for studying the variation of seasonal soil salinity in irrigated fields.

A highly selective electrochemical sensor for dopamine (DA) has been successfully prepared, which can effectively eliminate the interferences from ascorbic acid and uric acid. The detection limit for DA is obtained as 0.5 μM in aqueous solution.

Although the application of biological materials has shown potential in improving the environment of salinized soil, the impact on the transformation of soil phosphorus forms in salinized soil, especially when combined with B. mucilaginosus (BM), has rarely been studied. Therefore, this study investigated soil’s properties and phosphorus forms, as well as their relationship, in salinized soil after the application of different biological materials, including rice straw (RS), biochar (B), acidified biochar (AB), BM, RS+BM, B+BM, and AB+BM. A sequential extraction procedure was employed to determine the soil organic/inorganic phosphorus forms (Po/Pi). In our study, the contents of the soil’s resin-P, NaHCO₃-Pi, NaOH-Pi, and HCl-P increased by 50–341.66%, 4.08–184.63%, 37.45–163.45%, and 10.19–38.29%, respectively, with the application of the biological materials compared to with conventional fertilization (CK1). However, the contents of the soil’s NaHCO₃-Po, NaOH-Po, and residual-P significantly decreased in comparison to with CK1, particularly in the soils that received a combined application with biological materials and BM. Furthermore, the results from the statistical analysis revealed that the application of biological materials could increase the level of soil stable phosphorus, facilitate the transformation from soil stable phosphorus and soil unstable Po to soil unstable Pi, and enhance the effectiveness of soil phosphorus, especially when combined with BM, particularly in soil with AB+BM.

A novel, simple, and rapid colorimetric strategy is proposed based on the aggregation of gold nanoparticles (AuNPs) induced by the unfolding of G-quadruplex (G4) in the presence of silver ions (Ag⁺). AuNPs to which compact G4 structures were attached had higher stability toward salt-induced aggregation of AuNPs than those on which random coil single-stranded DNA (ssDNA) structures were anchored. In the Ag⁺-free system, AuNPs remained mono-dispersed. In contrast, upon addition of Ag⁺, the G4 structure unfolded, inducing aggregation of the AuNPs. The linear range of the as-established colorimetric assay for Ag⁺ was from 2.0 × 10⁻⁸ M to 2.0 × 10⁻⁶ M, with a detection limit of approximately 7 nM. Additionally, the colorimetric sensor showed good selectivity toward Ag⁺. The proposed method offers a new assay for metal ion-mediated aggregation-based colorimetric sensing and may pave a new way for heavy metal ions detection.