为全面客观分析土壤质量评价领域的研究动态和发展趋势,利用知识图谱工具 HistCite Pro 2.1、VOSviewer 1.6.19 和CiteSpace 6.1.R6 软件,基于Web of Science核心合集数据库,就近 10 年(2012-2022年)土壤质量评价领域的发文量、高被引文章、研究热点和研究趋势等进行计量分析.结果显示,近 10 年土壤质量评价领域的发文量呈上升趋势.关键词聚类网络划分出土壤健康评价、土壤质量评价、微生物指标 3类.应用机器学习算法评价土壤质量、筛选微生物指标构建评价最小数据集是当前土壤质量评价领域的两大研究热点.将机器学习模型应用于不同土壤类型、种植系统和管理措施下评价土壤质量,挖掘土壤核心功能微生物和优势菌种作为微生物评价指标是未来的研究趋势.

To reveal the effects of biogas slurry application on soil microbial community structure and function, a soil column experiment was constructed with three treatments[(no N addition, CM; conventional fertilization, SN; biogas slurry addition, SZ)]. The differences in composition, diversity, and structure of bacterial and fungal communities on day 1 and day 21 after soil flooding were evaluated, and their functions were predicted using Illumina high-throughput sequencing technology. The results of the analysis of α diversity showed that the fungal α-diversity indexes of CM, SN, and SZ treatments on day 1 were significantly higher than those on day 21, and there was no significant difference among the three treatments. However, the bacterial Simpson index differed among the three treatments on day 21, with SZ-21 showing a higher Simpson index but lower Chao1 index compared with those of SZ-21. The analysis of bacterial community structure showed that Firmicutes, Chloroflexi, and Actinobacteria in the SN-1 treatment were different from those in the other treatments on day 1, whereas the relative abundance of bacterial phyla in the SZ and SN treatments were similar on day 21. The analysis of fungal community structure showed that the relative abundance of Ascomycota and Zygomycota in the SZ-1 treatment were higher than those in the SN-1 and CM-1 treatments on day 1. The relative abundance of Ascomycota in the SN-21 and SZ-21 treatments were lower, whereas that of Zygomycota were higher compared with that in CM-21. The analysis of NMDS showed that the composition of bacterial and fungal communities in the SN and SZ treatments showed a gradually similar trend. The PICRUSt analysis showed that the function of the soil bacterial community was similar in the CM, SN, and SZ treatments. The FUNGuild function prediction reflected that the main differences in trophic type between the SN-21 and SZ-21 treatments occurred in saprotroph and pathotroph forms. Therefore, biogas slurry addition in the wheat-rice stubble stage could contribute to balancing soil nutrients and maintaining soil ecological function to a certain extent, but there may still be a risk of fungal disease.

为筛选餐厨垃圾沼液农田利用综合评价指标,本文以西兰花为研究对象,通过餐厨垃圾不同施用比例的田间试验,通过熵权法计算 3 大类(西兰花品质、土壤养分指标和土壤微生物指标)19 项指标的评价指标权重,确定各指标对餐厨垃圾沼液利用的敏感度.结果表明,西兰花维生素 C 含量在不同处理间的敏感度大于西兰花产量,土壤微生物群落和土壤养分对沼液施用比例响应较为一致.在西兰花种植模式下餐厨垃圾沼液施用风险评估可选择西兰花维生素 C含量、土壤微生物革兰氏阳性/革兰氏阴性菌比值、土壤全氮含量和土壤盐分饱和溶液电导率作为最小数据集评价.

To determine the reasonable rate of straw return and nitrogen (N) fertilizer use which may maintain soil ecosystem health, we analyzed their soil microbial biomass and composition in a 10-year field experiment with different rates of straw return (50%, 100%) and N fertilizer (270, 360, 450, 540 kg N ha−1 yr−1) by phospholipid fatty acid (PLFA) analysis and high-throughput sequencing. A rate of 50% straw return combined with 450 or 540 kg N ha−1 yr−1 effectively increased the soil available nutrient contents mainly for total nitrogen, available potassium, and available phosphorus. Total PLFAs indicated that straw return combined with N fertilizer promoted soil microbial growth and increased biomass. A rate of 100% straw return with 450 kg N ha−1 yr−1 was not conducive to the stability of the soil ecosystem according to the ratio of fungi to bacteria (F:B). The similar rate of straw returning and the similar level of nitrogen fertilizer application will be divided into the same cluster using a heatmap analysis. Some saprophytic fungi or pathogens became the dominant fungi genera, such as Gibberella, Sarocladium, Pseudallescheria, and Mycosphaerella, in the treatments with 100% straw returning combining higher N fertilizer (>450 kg ha−1 yr−1 yr−1 added). The relative abundances of some heavy metal-tolerant bacteria, such as those in Proteobacteria and Chlorobi, increased in the soils in the 100% straw return treatments. Therefore, the combined application of 100% straw returning and higher N fertilizer (>450 kg ha−1 yr−1) added long-term was not appropriate for soil health, which will lead to the risk of disease and pollution in soil.

为比较不同类型的土壤调理剂与叶面阻控剂、 养分管理对镉污染耕地小麦种植降镉(Cd)效果的影响,本文采用响应面法(RSM)中的中心组合设计Box-Behnken Design(BBD)研究了不同类型土壤调理剂、叶面阻控剂和养分调理措施在小麦种植中的降镉效果,探寻最优组合,试验结果显示,不同类别调理剂组合在小麦种植中的降镉效果存在明显差异,平均降镉率以生物型土壤调理剂组合效果最佳.响应曲面分析表明,每667 m2300 kg生物型调理剂配施200 kg有机肥可达到较理想的安全利用效果,即小麦每667 m2产量353 kg、 小麦籽粒镉含量0.058 mg·kg-1、 降镉率84.6％.

为合理使用氮肥,维持稻田生态健康发展,运用磷脂脂肪酸(PLFA)和Biolog-Eco微平板法研究了4种氮肥管理模式:不施氮肥(CK)、农民习惯施肥(FP)、氮肥优化管理1(OPT1)、氮肥优化管理2(OPT2)对稻田土壤微生物群落结构的影响.结果表明:OPT1处理较CK提高了土壤微生物的代谢活性和碳源利用能力,而FP、OPT2处理均较CK降低了土壤微生物代谢活性和碳源利用能力.OPT1处理的土壤总生物量最高,为42.11 nmol·g-1,OPT2处理的土壤总生物量为40.16 nmol·g-1,均高于CK的34.19 nmol·g-1,而FP处理的土壤总生物量为34.16 nmol·g-1,低于CK.OPT1处理的土壤微生物多样性较复杂,F/B值最高.综合各项指标,OPT1处理更有利于土壤生态环境稳定.

为探讨稻田沼灌的均匀性,选取了连续沼灌3a的稻田中离沼灌入口不同位置的土壤,分析其理化特性和微生物群落结构变化.结果表明,沼灌口附近土壤的有机质、 全氮、 有效氮、 有效磷、 速效钾含量高于距离沼灌口较远位置处,但其微生物量更低,说明稻田沼灌存在不均匀性.因此,长期应用管道设施在稻田中灌溉沼液时,需考虑沼液在田块中的均匀性.