中国农业科学 ›› 2025, Vol. 58 ›› Issue (4): 719-732.doi: 10.3864/j.issn.0578-1752.2025.04.008

• 土壤肥料·节水灌溉·农业生态环境 • 上一篇    下一篇

有机无机肥配施下旱地麦田土壤有机碳组分含量的变化特征

史帆1(), 李文广1, 易树生1, 杨娜1, 陈玉萌1, 郑伟1,2, 张雪辰1,2, 李紫燕1,2, 翟丙年1,2()   

  1. 1 西北农林科技大学资源环境学院,陕西杨凌 712100
    2 农业农村部西北植物营养与农业环境重点实验室,陕西杨凌 712100
  • 收稿日期:2024-04-16 接受日期:2024-05-28 出版日期:2025-02-16 发布日期:2025-02-24
  • 通信作者:
    翟丙年,E-mail:
  • 联系方式: 史帆,E-mail:1204971982@qq.com。
  • 基金资助:
    国家自然科学基金(31772389); 国家科技支撑计划项目课题(2015BAD23B04); 农业农村部公益性项目课题(201503124)

The Variation Characteristics of Soil Organic Carbon Fractions Under the Combined Application of Organic and Inorganic Fertilizers

SHI Fan1(), LI WenGuang1, YI ShuSheng1, YANG Na1, CHEN YuMeng1, ZHENG Wei1,2, ZHANG XueChen1,2, LI ZiYan1,2, ZHAI BingNian1,2()   

  1. 1 College of Natural and Environment, Northwest A&F University, Yangling 712100, Shaanxi
    2 Key Laboratory of Plant Nutrition and the Agri-Environment in Northwest China, Ministry of Agriculture and Rural Affairs, Yangling 712100, Shaanxi
  • Received:2024-04-16 Accepted:2024-05-28 Published:2025-02-16 Online:2025-02-24

摘要:

【目的】研究长期有机无机肥配施下土壤有机碳组分含量特征及各组分对旱地冬小麦产量的贡献,以期为提高西北旱地小麦产量和培肥土壤提供重要的理论依据。【方法】进行9年长期定位试验,采用裂区设计,主处理为两个有机肥水平(不施有机肥和施有机肥30 t·hm-2,分别用M0和M1表示),副处理为5个氮水平(施氮量分别为0、75、150、225、300 kg·hm-2,分别用N0、N75、N150、N225和N300表示)。主要分析有机无机肥配施下冬小麦籽粒产量、土壤有机碳组分(包括溶解性有机碳(DOC)、微生物量碳(MBC)、颗粒有机碳(POC)和矿质结合态有机碳(MOC))的含量特征及各组分质量分数的差异,并且量化各有机碳组分对小麦籽粒产量的贡献。【结果】随施氮量的增加,冬小麦产量呈先增加后降低的趋势。相较于单施化肥,有机无机肥配施冬小麦平均增产4.80%。M1N150处理下冬小麦产量最高(8 143.2 kg·hm-2),较M0N0处理增加了85.36%,且较当地常规施肥施氮量降低了75 kg·hm-2。经过9年连续施肥,M1N150处理下的SOC含量相较试验初始(2014年)显著提升了17.9%,即在施氮150 kg·hm-2的基础上配施有机肥30 t·hm-2不仅会显著提升土壤的培肥效果,还会在减施氮肥的基础上提高冬小麦产量。通过分析不同施肥处理下土壤有机碳组分发现,与单施化肥相比,有机无机肥配施不同程度地提高了POC、DOC和MBC组分含量,以及POC组分在SOC中的占比。通过SOC与各有机碳组分含量的敏感性指数发现,土壤活性有机碳组分(DOC、MBC、POC)对有机无机肥配施处理均有显著响应,其中POC和DOC组分对农田管理措施的响应最为敏感。通过对土壤各有机碳组分与小麦产量的相关性分析表明,POC、DOC和MBC组分对产量的提高均有积极效果。随机森林分析结果进一步证明,有机无机肥配施下POC和DOC组分对小麦产量的贡献度更高。因此,可以推断有机无机肥配施对作物生产率和土壤肥力的提高,主要是通过增加土壤中有机碳的DOC和POC含量来达到的。【结论】在施氮150 kg·hm-2的基础上配施有机肥30 t·hm-2时,更有利于提升西北旱地麦田土壤有机碳和活性有机碳组分含量,进而提高旱地冬小麦产量,其中以DOC和POC组分对小麦产量贡献度最高。

关键词: 旱地, 冬小麦, 有机无机肥配施, 产量, 土壤有机碳组分

Abstract:

【Objective】This experiment was conducted to study the content characteristics of soil organic carbon components under long-term organic and inorganic fertilizers and the contribution of each component to the yield of winter wheat in dryland, with a view to providing an important theoretical basis and practical value for the increase of wheat yield and soil fertilization in Northwest dryland. 【Method】This study was based on a nine-year long-term positioning experiment, using a fissure design, with two organic fertilizer levels (M0 and M1) for the main treatment, and five nitrogen levels (N0, N75, N150, N225, N300) for the side treatment. The variation characteristics of winter wheat grain yield and soil organic carbon and its components were analyzed, including dissolved organic carbon (DOC), microbial biomass carbon (MBC), particulate organic carbon (POC), and mineral organic carbon (MOC), as well as the differences in the mass fractions of the components, and the contribution of each component of organic carbon to wheat grain yield was quantified. 【Result】With the increase of nitrogen application rate, the wheat grain yield increased first and then decreased, while the grain yield of wheat increased by 4.80% under organic fertilizers than that under chemical fertilizers alone. The highest yield (8 143.2 kg·hm-2) was obtained under M1N150 treatment, which increased by 85.36% compared with M0N0 treatment, and this fertilizer application decreased by 75 kg·hm-2 compared with the local conventional nitrogen application. After 9 years of continuous fertilizer application, the SOC content under M1N150 treatment was significantly increased by 103.30% compared than the soil at the initial stage of the experiment (2014). That is, the nitrogen rate of 150 kg·hm-2 combined with 30 t·hm-2 organic fertilizer would not only significantly improve the soil fertilizer cultivation effect, but also increase the winter wheat yield on the basis of reducing nitrogen application. The study of soil organic carbon fractions under different fertilization treatments showed that, compared with chemical fertilizers alone, the organic and inorganic fertilizers combined treatments increased the content of POC, DOC and MBC fractions as well as the proportion of POC fractions in SOC. The sensitivity indices of SOC and the contents of each organic carbon component showed that the soil active organic carbon components (DOC, MBC and POC) responded significantly to the organic and inorganic fertilizer treatments, among which the POC and DOC components were the most sensitive to the response of farmland management measures. The correlation analysis between soil organic carbon components and wheat yield showed that POC, DOC and MBC components had positive effects on yield increase; the results of Random Forest Analysis (RFA) further proved that the POC and DOC components contributed more to wheat yield under the combined application of organic and inorganic fertilizers. Therefore, it could be inferred that the increase of crop productivity and soil fertility by organic and inorganic fertilization was mainly achieved by increasing the DOC and POC content of organic carbon in the soil. 【Conclusion】When 150 kg·hm-2 of nitrogen was applied with 30 t·hm-2 of organic fertilizer, it was more conducive to the enhancement of the content of soil organic carbon and reactive organic carbon fractions in wheat fields in the drylands of Northwest China, which in turn improved the yield of winter wheat in dryland, with the DOC and POC fractions contributing the most to the yield of wheat.

Key words: dryland, winter wheat, application of organic and inorganic fertilizers, yield, soil organic carbon fraction