文字来源：南京土壤所官网
图片来源：Science Bulletin官网
黑土地是东北粮食安全的重要基础，但在气候变化与高强度利用的背景下不断退化。土壤生物多样性被认为是支撑土壤肥力、碳固持、病原菌控制和生态系统稳定的关键，但“哪些土壤生物更为重要”，“多样性如何影响农业功能”，“黑土地健康的生物指示因子是什么”等问题仍缺乏系统量化和区域尺度证据。
对此，中国科学院南京土壤研究所褚海燕课题组在东北典型黑土区开展了玉米农田的大尺度调查，采用PacBio长读长测序技术，实现了对土壤真菌、原生生物、藻类及后生动物等真核生物群落的全面解析。研究揭示，真菌多样性是决定黑土地多项生态与农业功能的关键。其中，一个被长期忽视但在该研究中表现极为显著的类群——Rozellomycota（真菌基部类群），是提升土壤有机碳含量和作物产量的最强预测因子：其多样性越高，土壤有机碳越丰富、作物生长越旺盛。与此同时，被认为是农业风险源的潜在植物病原真菌（PPF）在该研究中表现出明确的负面效应：其多样性越高，作物产量越不稳定，土壤对病原生物的抑制力越弱。PPF多样性成为黑土地健康与农业可持续性的敏感“预警指标”。真菌 Shannon与Chao1多样性指数则显著增强土壤碳稳定性和整体土壤生物多样性，表明了真菌在黑土地生态系统中的关键地位。经多种统计模型（多元回归、随机森林和结构方程模型）验证，一致表明：在复杂的环境、空间和地形约束下，真菌多样性始终保持强劲而稳定的预测能力，是“黑土生物健康的核心引擎”。
Fig. 1. Sample map and soil sampling protocols in the black soil region of Northeast China. (a) Distribution of 52 sample sites (100 m × 100 m) across the black soil region of Northeast China. (b) Soil sampling protocol at each site: five plots (10 m × 10 m) were established at the four corners and the center. Within each plot, nine soil cores (3.5 cm diameter, 0–15 cm depth) were collected and combined to form a composite sample. In total, 260 plots were surveyed. (c) Example of a sample site in Changchun, Jilin Province (latitude: 44.1857, longitude: 125.6013).
Fig. 2. Piecewise structural equation models illustrating the primary effects of fungal diversity on soil functions under the constraints of major climatic and soil predictors. (a) Model predicting SOC content and crop productivity. (b) Model predicting SOC persistence and soil biodiversity. (c) Model predicting productivity stability and pathogen control. Only significant paths are shown (***P < 0.001, **P < 0.01, *P < 0.05), with standardized path coefficients (SPC) indicated alongside each path. Positive and negative paths are represented in light green and red, respectively, and line widths correspond to SPC values. n = 260. (d) Fungal diversity at the core: radar framework of soil health and agricultural sustainability. Fungal diversity is represented by the fungal Shannon and Chao1 indices, Rozellomycota richness (positive indicator), and PPF richness (negative indicator). SOC content and SOC persistence represent soil fertility and climate resilience, respectively. In the radar chart, each point’s position reflects the magnitude of the total SPC, with solid and hollow points indicating positive and negative effects, respectively. Major environmental factors influencing these multiple soil health and agricultural sustainability objectives are shown on the outer ring, with varying levels of color transparency.
上述研究成果以“Fungal diversity drives soil health and agricultural sustainability in black soils”为题发表在Science Bulletin期刊上。杨腾副研究员与柳旭博士为论文共同第一作者，褚海燕研究员为通讯作者。该研究得到国家重点研发计划（2022YFD1500202）和中国科学院先导专项（XDA28020202）等项目的资助。
