The problem of cultivated land soil quality in the Huaihe River Basin has become increasingly prominent. How to accurately and quantitatively evaluate the soil quality of regional cultivated land and realize its efficient use has become an urgent problem. In order to explore the spatial autocorrelation and variation in soil nutrients in cultivated land in the plain of Fengtai County in the Huaihe River Basin, a total of 306 soil samples and mature wheat samples were collected in the study area to analyze soil pH, total nitrogen (TN), available nitrogen (AN), available phosphorus (AP), available potassium (AK) and slow-release potassium (SK) content and wheat biomass, and combined with geostatistical methods and GIS technology. The Kriging interpolation method and Moram‘s I index method were systematically analyzed. Principal component analysis (PCA) and Pearson correlation analysis were used to establish the minimum data set (MDS) of soil quality, which was used to calculate the soil quality index (SQI) and determine the key factors affecting soil quality. The results showed that the soil pH was in weak variation, and the other nutrient indexes were in medium variation. The spatial variability of soil-available potassium nutrients was affected by random factors such as human activities and structural factors such as soil parent materials. The spatial autocorrelation of organic matter, total nitrogen, alkali-hydrolyzable nitrogen, available phosphorus, available potassium and mitigation potassium was weak, which was mainly affected by random factors such as human activities. An unequivocal positive spatial nexus was discerned across all nutrients. Cumulatively, the nutrient dispersion across the investigated territory was somewhat diffuse, manifesting in a mosaic pattern with pronounced zonal nutrient allocation disparities in the meridional, median, and septentrional segments. An explicit latitudinal dichotomy delineating zones of nutrient opulence and paucity was also observed. These insights can pave the way for tailored fertilization strategies and judicious pedological stewardship in Fengtai County.

Cadmium (Cd) pollution in soil has become a huge problem for agricultural production in China and even the world. Passivation and phytoremediation are two important remediation technologies for Cd pollution. In this study, the cadmium-contaminated and phosphorus-poor farmland soil around a mining area in Huainan was taken as the research object, and the remediation effect of biochar and phosphorus-containing materials on soil cadmium pollution was discussed. The results showed that the combined application of biochar and phosphorus-containing materials significantly reduced the pH of non-rhizosphere soil and rhizosphere soil, and increased the content of soil dissolved organic carbon (DOC). The combined application of biochar and phosphorus-containing materials significantly reduced soil pore water Cd and soil available Cd. In addition, both a single application of biochar and synergistic application of biochar and phosphorus-containing materials significantly increased the biomass of aboveground and underground parts of amaranth and soil urease and catalase activities. Phosphorus application reduced the bioavailability of Cd in soil. With the increase in phosphorus application, the content of available Cd in soil decreased significantly, and there was a certain negative correlation between Cd content and phosphorus content in plants. The abundance of beneficial microorganisms such as Ochrobactrum, Anaerolinea, Achromobacter, and Cellvibrio in soil was significantly increased after the synergistic application of biochar and phosphorus-containing materials.

Soil environmental quality in townships is related to the development of rural revitalization and the smooth flow of urban-rural integration and development. However, the quality of soil environment in townships may be exposed to potential risks of potentially toxic elements pollution due to the influence of production and life. Thus, this study is based on descriptive statistical analysis, source identification, and systematic assessment of ecological and human health risks. The results showed that the mean content of eight potentially toxic elements in the study area was lower than the background value of the soil environment in Hebei Province only for the elements As, Pb, Zn and Hg, and the exceeding rate of Cr, Cu, Cd and Ni was higher than 55%. APCS-MLR model identified five categories of pollution sources with the following sources and contributions: industrial sources (47.1%), transportation sources (24.3%), natural sources (13.8%), agricultural sources (3.8%), and atmospheric deposition sources (11.0%). Ecological risks are mainly attributed to Cd and Hg, with high-risk areas concentrated in the central part of the study area. Probabilistic health risks indicate that adult and pediatric THI values are within the safe range at the 95% confidence interval and that children have some significant carcinogenic risk. Source contribution to health risk indicates that industrial and transportation sources are important sources of control for cancer risk, yet elemental As are less enriched, so there is no need to pay much attention to the impact of natural sources on health risk. In conclusion, this study provides a reference for risk prevention and potential source identification of potentially toxic elements in the top soil of the township.

Addressing capacity assessment uncertainties in high-geological-background areas, this study develops a source-oriented risk assessment framework integrating spatial interpolation, source apportionment, and dynamic capacity modeling. Analysis of 39 surface soil samples (As, Cr, Ni, Cu, Zn, Cd, Pb, Se, pH) from Ankang Basin, China, reveals: Two heavy metal sources were quantitatively identified via APCS-MLR. Natural sources (71.94%) dominate, contributing Se, Cd, Cu, Zn, and Ni, with Cd primarily geogenic. Anthropogenic sources (28.06%) from industrial, transportation, and agricultural activities contribute Cr, As, Pb, and Ni. Static capacity assessment identifies Cd as the primary limiting element (average capacity 0.22). Dynamic model predictions indicate that the 20-year dynamic capacity of all elements is only 14–20% of the theoretical static capacity (Q_i), representing 16–47% of the current existing capacity, and will approach dynamic equilibrium after 40 years. Source-oriented capacity indices reveal natural sources pose the highest comprehensive risk (SPI = 0.916), mainly driving Cd capacity stress (SPICd = 0.34). Anthropogenic sources remain safe (SPI > 1.255) but warrant Pb monitoring. This framework supports precise management of selenium-rich lands, shifting strategies from emission control to avoiding high-risk geological units.