Soil acidification reduces the abundance and activity of beneficial microorganisms, impairs tea plant growth, and ultimately leads to a decline in tea quality. Maintaining healthy soil is critical for sustainable tea agriculture. However, the interactive effect of biochar and nitrogen fertilizer on the microbial community structure and function in acidic tea plantation soils remains unclear. This study was designed to explore whether the co-application of biochar and fertilizer could enhance soil properties and maintain microbial health in tea plantations. Three treatments were set up through a controlled pot experiment: no fertilizer or biochar application (B₀N₀), fertilizer without biochar (B₀N₁), and biochar with fertilizer (B₁N₁). High-throughput sequencing technology was used to investigate the characteristics of soil microbial communities in tea plantations. Biochar amendment increased soil pH by 0.8 units, organic matter and total nitrogen by 13.5% and 21.4%, and reduced NH₄⁺-N and NO₃⁻-N leaching by 10.8% and 12.9%, respectively. It also modulated microbial community structure, enhanced the abundance of nitrogen-cycling genes (e.g., narB, nirK, nosZ), and influenced nitrogen availability through adsorption. Nitrate was identified as the main factor shaping microbial communities under fertilization. These results highlight the potential of biochar as a sustainable amendment to improve soil health and nitrogen retention in tea cultivation systems. Further field studies are warranted to validate its efficacy in enhancing tea productivity and reducing environmental nitrogen losses under real-world conditions.

The large-scale generation of vegetable waste in China has become a significant environmental concern. The traditional method of composting results in high nitrogen losses during the process and in the final product. To address this issue and shorten the composting period, this study investigated the effects of bamboo vinegar (BV) and a microbial inoculant (MI) on the physical and chemical properties of the compost and bacterial community composition during the composting process. The results revealed that the addition of BV and BV + MI decreased the time required to reach thermophilic temperatures and conserved nitrogen in the final product. Furthermore, it was found that the dominant nitrifying and denitrifying bacteria, as identified through 16S rDNA analysis, belonged to Nitrosomonas and Proteobacteria, respectively. BV and BV + MI reduced NH₃ and N₂O emissions, which suggested that BV is a beneficial composting agent that preserves nitrogen during the composting process.

This study evaluates the efficacy of buried straw bioreactor (SBR) technology in enhancing soil properties, CO₂ efflux, and crop yield, specifically focusing on Indian cowpea cultivation within a greenhouse environment. Conducted at the Yuxi Demonstration Park in Fujian, China, the experiment utilized a randomized block design incorporating seven treatments with varying straw application rates (4.5, 6, and 7.5 kg m⁻²) and burial depths (20 and 30 cm) alongside a control group. The investigation revealed that SBR technology significantly increased soil temperature, CO₂ efflux, soil total nitrogen (TN), and total organic carbon (TOC), contributing to a marked improvement in the biomass of Indian cowpea roots, stems, and leaves. Notably, the optimal results were observed with 7.5 kg m⁻² straw applied at a 20 cm depth, enhancing soil temperature by 1.5–2.0 °C and multiplying cowpea biomass by 2.1–6.4 times relative to the control. This treatment also led to the highest increases in soil TOC and CO₂ efflux, demonstrating the potential of SBR technology for carbon sequestration and suggesting its application as a sustainable agricultural practice in cold regions to ameliorate the soil’s physical and nutritional characteristics, thus supporting enhanced crop production. The study underscores SBR technology’s role in addressing the challenge of agricultural waste through the effective reuse of crop straw, promoting the circular development of agriculture while safeguarding the ecological environment.