麦田土壤团聚体及其有机碳、全氮分布特征对绿肥还田结合氮肥减施的响应

doi:10.3864/j.issn.0578-1752.2026.14.008

摘要/Abstract

摘要：

【目的】基于定位试验探讨土壤团聚体及其有机碳、全氮的分布特征对绿肥还田结合氮肥减施的响应，旨在为该区域小麦生产中制定合理的培肥制度提供理论依据。【方法】基于始于2018年田间定位试验中的7个处理：N100（无绿肥还田，施氮180 kg∙hm^-2），G1N85（15 000 kg∙hm^-2绿肥配施氮153 kg∙hm^-2），G2N85（22 500 kg∙hm^-2绿肥配施氮153 kg∙hm^-2），G3N85（30 000 kg∙hm^-2绿肥配施氮153 kg∙hm^-2），G1N70（15 000 kg∙hm^-2绿肥配施氮127 kg∙hm^-2），G2N70（22 500 kg∙hm^-2绿肥配施氮127 kg∙hm^-2）和G3N70（30 000 kg∙hm^-2绿肥配施氮127 kg∙hm^-2）。利用该定位试验2024、2025年数据，分析其对土壤团聚体组成及碳氮养分的影响。【结果】与N100相比，绿肥还田结合氮肥减施显著增加了0—20和20—40 cm土层大团聚体（>0.25 mm）的含量，并且提高了平均重量直径（MWD）和几何平均直径（GMD），其中G3N85处理效果最优。G3N85较其他处理提高了所有粒级团聚体中有机碳和全氮含量，其中>2 mm、2—0.25 mm、0.25—0.053 mm和<0.053 mm粒级团聚体中有机碳增幅为0.7%—12.9%、1.3%—12.4%、1.2%—15.0%和3.2%—13.4%，全氮增幅为3.1%—11.4%、3.6%—11.1%、2.1—13.1%和4.9%—10.9%，且该处理大团聚体中有机碳和全氮对土壤有机碳和全氮的贡献率显著提高，增量为19.7%、23.3%和19.6%和24.2%；微团聚体和粉黏粒中的有机碳和全氮对土壤有机碳和全氮贡献率则显著降低。【结论】绿肥还田结合氮肥减施在提高0—40 cm土层大团聚体含量和稳定性的同时，还提高了团聚体中有机碳和全氮对土壤有机碳和全氮的贡献率，其中绿肥还田30 000 kg∙hm^-2结合施氮153 kg·hm^-2处理效果最优，可作为河西绿洲灌区麦田维持土壤结构稳定性、促进碳氮累积的合理施肥制度。

关键词: 小麦, 绿肥还田, 氮肥减施, 团聚体组成, 团聚体稳定性, 团聚体碳氮分布

Abstract:

【Objective】Based on a long‑term field experiment, this study investigated the response of soil aggregate distribution characteristics, along with their associated organic carbon and total nitrogen contents, to green manure incorporation combined with nitrogen reduction. The aim was to provide a theoretical basis for developing rational soil fertility management practices in wheat production in this region.【Method】Based on seven treatments from a long‑term field experiment initiated in 2018: N100 (no green manure incorporation with 180 kg∙hm^-2 nitrogen), G1N85 (15 000 kg∙hm^-2 green manure+153 kg∙hm^-2nitrogen), G2N85 (22 500 kg∙hm^-2 green manure+153 kg∙hm^-2 nitrogen), G3N85 (30 000 kg∙hm^-2 green manure+153 kg∙hm^-2 nitrogen), G1N70 (15 000 kg∙hm^-2 green manure+127 kg∙hm^-2 nitrogen), G2N70 (22 500 kg∙hm^-2 green manure+127 kg∙hm^-2 nitrogen), and G3N70 (30 000 kg∙hm^-2 green manure+127 kg∙hm^-2 nitrogen). Using data from this field experiment collected in 2024 and 2025, we analyzed the effects of these treatments on soil aggregate composition and carbon‑nitrogen nutrient contents.【Result】Compared to N100, the combination of green manure incorporation and reduced nitrogen fertilizer application not only significantly increased the content of large soil aggregates (>0.25 mm) in the 0-20 cm and 20-40 cm soil layers of wheat fields but also enhanced the mean weight diameter (MWD) and geometric mean diameter (GMD), with the G3N85 treatment yielding the optimal effect. Compared to other treatments, G3N85 increased the organic carbon and total nitrogen content of all particle size agglomerates. with increases in organic carbon content of 0.7%-12.9%, 1.3%-12.4%, 1.2%-15.0%, and 3.2%-13.4% for aggregates >2 mm, 2-0.25 mm, 0.25-0.053 mm, and <0.053 mm, respectively. while aggregate total nitrogen increased by 3.1%-11.4%, 3.6%-11.1%, 2.1%-13.1%, and 4.9%-10.9%, respectively. Moreover, the contribution rates of organic carbon and total nitrogen in large aggregates to soil organic carbon and total nitrogen significantly increased under this treatment, with increases of 19.7%, 23.3%, 19.6%, and 24.2%, respectively. Conversely, the contribution rates of organic carbon and total nitrogen from micro-aggregates and silt-clay particles to soil organic carbon and total nitrogen significantly decreased.【Conclusion】The combination of green manure incorporation and reduced nitrogen fertilizer application not only increased the content and stability of large soil aggregates in the 0-40 cm layer but also enhanced the contribution rates of organic carbon and total nitrogen in these aggregates. The optimal treatment was applying 30 000 kg∙hm^-2 of green manure combined with 153 kg∙hm^-2 of nitrogen fertilizer. This regimen can serve as a rational fertilization system for maintaining soil structure stability and promoting carbon-nitrogen accumulation in wheat fields in the Hexi Oasis irrigation district.

Key words: wheat, green manure incorporation, reduced nitrogen fertilizer application, aggregate composition, aggregate stability, carbon-nitrogen distribution in aggregates

冯振康, 于爱忠, 尹波, 张冬玲, 蔡宏玮, 侯世和, 黄亚丽, 于彦子, 霍建喆, 庞小能. 麦田土壤团聚体及其有机碳、全氮分布特征对绿肥还田结合氮肥减施的响应[J]. 中国农业科学, 2026, 59(14): 3094-3104.

FENG ZhenKang, YU AiZhong, YIN Bo, ZHANG DongLing, CAI HongWei, HOU ShiHe, HUANG YaLi, YU YanZi, HUO JianZhe, PANG XiaoNeng. Soil Aggregates in Wheat Fields and Their Carbon and Nitrogen Distribution Characteristics in Response to Green Manure Application Combined with Reduced Nitrogen Fertilizer Application[J]. Scientia Agricultura Sinica, 2026, 59(14): 3094-3104.

图/表 7

图1

表1

图2

图3

图4

图5

表2

不同处理各粒级团聚体中有机碳、全氮对土壤有机碳和全氮的贡献率"

年份 Years	土层 Soil layer (cm)	处理 Treatment	有机碳贡献率 OC contribution rate (%)				全氮贡献率 TN contribution rate (%)
年份 Years	土层 Soil layer (cm)	处理 Treatment	2 mm	2-0.25 mm	0.25-0.053 mm	<0.053 mm		2-0.25 mm	0.25-0.053 mm	<0.053 mm
2024	0-20	N100	5.1b	41.7b	25.6ab	19.2a	5.2c	42.8b	21.3a	21.1a
		G1N85	6.4b	45.1ab	22.4abc	19.1a	6.1abc	43.5ab	22.0a	19.9b
		G2N85	7.0a	45.4ab	22.3bc	18.3a	6.8ab	44.8ab	20.9a	19.6b
		G3N85	7.7a	48.3a	20.0c	18.0a	7.5a	48.5a	17.9a	19.4b
		G1N70	6.1ab	43.8b	26.3a	19.3a	5.9bc	44.4ab	21.0a	20.1b
		G2N70	6.7a	44.9ab	21.3bc	18.7a	6.5bc	44.3ab	21.6a	19.7b
		G3N70	7.2a	46.0ab	21.8c	18.0a	7.1b	45.5ab	20.0a	19.4b
	20-40	N100	4.4d	39.2c	28.2a	19.0a	4.2d	38.7c	26.6ab	20.4a
		G1N85	5.3c	41.8bc	25.7ab	18.7a	5.1d	41.2c	24.5b	20.0a
		G2N85	5.8bc	43.5c	24.1abc	18.9a	5.5bc	42.6bc	22.6b	20.0a
		G3N85	6.8a	47.7a	20.3c	18.5a	6.4a	46.9a	19.1c	19.6ab
		G1N70	5.5c	42.2bc	25.6b	18.8a	4.8cd	38.8c	29.1a	19.6ab
		G2N70	5.7c	43.4c	23.9abc	18.8a	5.1bcd	40.5d	27.0ab	19.5ab
		G3N70	6.5ab	44.8b	23.0bc	18.6a	6.1b	44.2ab	23.9b	19.0c
2025	0-20	N100	5.0c	41.2c	25.7a	19.8a	5.2d	39.9e	22.3a	21.3ab
		G1N85	6.5b	44.5c	22.6bc	18.7a	6.6c	44.6c	22.9a	20.1ab
		G2N85	6.9ab	45.2bc	21.4bcd	18.7a	6.9b	43.9bcd	20.8ab	19.7ab
		G3N85	7.9a	49.1a	19.4d	18.0a	7.8a	47.8a	18.4b	18.8b
		G1N70	6.2bc	43.9bc	23.2b	18.9a	5.7cd	41.5d	20.9ab	18.2b
		G2N70	6.7ab	44.6bc	21.4bcd	18.6a	6.5c	43.0de	21.0ab	18.9b
		G3N70	7.3ab	46.4b	20.7cd	17.9a	7.3ab	45.9ab	20.2ab	19.0b
	20-40	N100	4.6c	39.6c	28.3a	18.9a	4.3c	39.2e	27.3a	20.2e
		G1N85	5.4b	43.7b	26.0abc	18.1a	5.0c	42.7bc	26.3ab	19.2bc
		G2N85	6.0b	44.9ab	24.7bc	19.6a	5.5b	43.1bc	24.8ab	20.2bc
		G3N85	6.8a	47.2a	20.9d	17.4a	6.5a	47.3bc	20.9c	18.7a
		G1N70	5.9b	42.2c	26.5b	18.5a	5.3b	40.1e	26.5ab	19.3de
		G2N70	5.7b	41.9c	23.9bc	18.2a	5.3b	41.5cd	24.4ab	19.7cd
		G3N70	6.8a	44.7ab	23.4cd	17.6a	6.4a	44.6b	23.4bc	18.4b

表2

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