The release of endogenous phosphorus (P) from sediments is the main cause of lake eutrophication, even after the successful control of exogenous P. Among others, the release of iron-bound P is a major source of endogenous P, and it is necessary to reduce the P concentration by enhancing iron–phosphorus binding. Iron (Fe)-modified biochar adsorption is an effective and widely used method for fixing P in sediments. In this paper, the modification method, mechanism, and application effect of Fe-modified biochar are reviewed. It is found that most of the modification methods are realized through a physicochemical pathway. Therefore, the prospect of biochar modification through a biological pathway is presented. In particular, the possible application of iron-oxidizing bacteria (IOB) for promoting iron–phosphorus binding and biochar modifications is discussed. The potential effects of biochar additions on microbial communities in water and sediments are also discussed. In the future research, emphasis should be placed on the adsorption mechanism and effect analysis in simulated polluted environments before large-scale use, to ensure the economic practicability and sustainability of Fe-modified biochar applications.

Textile dyes are one of the major water pollutants released into water in various ways, posing serious hazards for both aquatic organisms and human beings. Bioremediation is a significantly promising technique for dye decolorization. In the present study, the fungal strain Lasiodiplodia sp. was isolated from the fruiting bodies of Schizophyllum for the first time. The isolated fungal strain was examined for laccase enzyme production under solid-state fermentation conditions with wheat bran (WB) using ABTS and 2,6-Dimethoxyphenol (DMP) as substrates, then the fermented wheat bran (FWB) was evaluated as a biosorbent for Congo red dye adsorption from aqueous solutions in comparison with unfermented wheat bran. A Box–Behnken design was used to optimize the dye removal by FWB and to analyze the interaction effects between three factors: fermentation duration, pH, and dye concentration. Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), and scanning electron microscopy (SEM) were applied to study the changes in the physical and chemical characteristics of wheat bran before and after fermentation. An additional experiment was conducted to investigate the ability of the Lasiodiplodia sp. YZH1 to remove Congo red in the dye-containing liquid culture. The results showed that laccase was produced throughout the cultivation, reaching peak activities of ∼6.2 and 22.3 U/mL for ABTS and DMP, respectively, on the fourth day of cultivation. FWB removed 89.8% of the dye (100 mg L⁻¹) from the aqueous solution after 12 h of contact, whereas WB removed only 77.5%. Based on the Box–Behnken design results, FWB achieved 93.08% dye removal percentage under the conditions of 6 days of fermentation, pH 8.5, and 150 mg L⁻¹ of the dye concentration after 24 h. The fungal strain removed 95.3% of 150 mg L⁻¹ of the dye concentration after 8 days of inoculation in the dye-containing liquid culture. These findings indicate that this strain is a worthy candidate for dye removal from environmental effluents.

Plastic film mulching is widely used in protected agriculture. However, the residues of various types of plastic films, as a consequence, severely affect soil quality. The most widely promoted alternative strategy is the use of biodegradable plastic films. Nevertheless, the research on the effects of different types of plastic films on soil properties remains insufficient. This study explored the impacts of different plastic film mulching on the physicochemical properties and microbial communities of soils for pepper cultivation, with three treatments: traditional polyethylene film (PE-Ctr), PBAT biodegradable film (PBAT bio), and reinforced polyethylene film (RPE). The results showed that the soil pH value was the highest in PE-Ctr treatment, and the soil organic matter content was higher in the biodegradable film treatment, while the electrical conductivity (EC), nitrate, and some cations (Ca²⁺, Mg²⁺) were higher in the RPE treatment. The contents of available trace element Zn, Fe, and Mn increased in the PBAT bio treatment. The bacterial richness and evenness indices were higher in PBAT bio treatment than those of other treatments. The fungal community had a relatively high richness, but a lower evenness, compared to the PE-Ctr and PBAT bio treatments. The use of different plastic films significantly affected the composition of soil bacteria, while differences in the composition of soil fungi were only observed between the PBAT bio and RPE treatments. Proteobacteria, Acidobacteriota, and Actinobacteriota were the most dominant bacterial phyla, and Ascomycota and Mortierellomycota were the dominant fungal phylum across all treatments. FAPROTAX functional prediction showed that the abundances of multiple functions of soil bacteria were higher in the RPE treatment, and the chemoheterotrophy function was higher in the PE treatment. FUNGuild analysis indicated that the trophic types and ecological function groups of soil fungi were more abundant in the PBAT bio treatment.