Institute of Environment and Sustainable Development in Agriculture, Chinese Academy of Agricultural Sciences, Beijing, 100081, China; Western Agricultural Research Center, Chinese Academy of Agricultural Sciences, Changji, Xinjiang, 831100, China; Key Laboratory of Low-carbon Green Agriculture in North China, Ministry of Agriculture and Rural Affairs, Beijing, 100081, China.
Institute of Environment and Sustainable Development in Agriculture, Chinese Academy of Agricultural Sciences, Beijing, 100081, China; Key Laboratory of Low-carbon Green Agriculture in North China, Ministry of Agriculture and Rural Affairs, Beijing, 100081, China.
J Environ Manage. 2024 Apr;356:120641. doi: 10.1016/j.jenvman.2024.120641. Epub 2024 Mar 21.
Biogas slurry, a by-product of the anaerobic digestion of biomass waste, predominantly consisting of livestock and poultry manure, is widely acclaimed as a sustainable organic fertilizer owing to its abundant reserves of essential nutrients. Its distinctive liquid composition, when tactfully integrated with a drip irrigation system, unveils immense potential, offering unparalleled convenience in application. In this study, we investigated the impact of biogas slurry topdressing as a replacement for chemical fertilizer (BSTR) on soil total organic carbon (TOC) fractions and carbon (C)-degrading enzyme activities across different soil depths (surface, sub-surface, and deep) during the tasseling (VT) and full maturity stage (R6) of maize. BSTR increased the TOC content within each soil layer during both VT and R6 periods, inducing alterations in the content and proportion of individual C component, particularly in the topsoil. Notably, the pure biogas slurry topdressing treatment (100%BS) compared with the pure chemical fertilizer topdressing treatment (CF), exhibited a 38.9% increase in the labile organic carbon of the topsoil during VT, and a 30.3% increase in the recalcitrant organic carbon during R6, facilitating microbial nutrient utilization and post-harvest C storage during the vigorous growth period of maize. Furthermore, BSTR treatment stimulated the activity of oxidative and hydrolytic C-degrading enzymes, with the 100%BS treatment showcasing the most significant enhancements, with its average geometric enzyme activity surpassing that of CF treatment by 27.9% and 27.4%, respectively. This enhancement facilitated ongoing and efficient degradation and transformation of C. Additionally, we screened for C components and C-degrading enzymes that are relatively sensitive to BSTR. The study highlight the advantages of employing pure biogas slurry topdressing, which enhances C component and C-degrading enzyme activity, thereby reducing the risk of soil degradation. This research lays a solid theoretical foundation for the rational recycling of biogas slurry.
沼液是生物质废弃物厌氧消化的副产物，主要由畜禽粪便组成，由于其富含大量必需营养物质，被广泛认为是一种可持续的有机肥料。其独特的液体成分，当与滴灌系统巧妙结合时，具有巨大的潜力，在应用方面提供了无与伦比的便利性。在这项研究中，我们研究了沼气液追肥替代化肥（BSTR）对不同土壤深度（表层、次表层和深层）在玉米抽雄期（VT）和完全成熟期（R6）土壤总有机碳（TOC）分数和碳（C）降解酶活性的影响。BSTR 在 VT 和 R6 期间均增加了每个土壤层的 TOC 含量，导致个别 C 成分的含量和比例发生变化，特别是在表土层。值得注意的是，与纯化肥追肥处理（CF）相比，纯沼气液追肥处理（100%BS）在 VT 期间使表土中易分解有机碳增加了 38.9%，在 R6 期间使难分解有机碳增加了 30.3%，促进了微生物对养分的利用和收获后 C 的储存，有利于玉米旺盛生长期间的 C 储存。此外，BSTR 处理刺激了氧化和水解 C 降解酶的活性，其中 100%BS 处理的平均几何酶活性分别比 CF 处理高 27.9%和 27.4%。这种增强作用促进了 C 的持续和有效降解和转化。此外，我们筛选了对 BSTR 相对敏感的 C 成分和 C 降解酶。该研究强调了纯沼气液追肥的优势，它增强了 C 成分和 C 降解酶的活性，从而降低了土壤退化的风险。这项研究为沼气液的合理回收利用奠定了坚实的理论基础。
