摘要
【目的】为揭示有机肥替代化肥氮对盐碱土壤碳循环的影响机制,评估其对土壤肥力与生态功能的提升效果,通过不同替代比例的田间试验,解析有机肥对盐碱土有机碳矿化过程的调控作用。【方法】以宁夏引黄灌区轻、中、重度盐碱地土壤为研究对象,单施化肥(F100)为对照,设置有机肥替代15%(O15F85)、30%(O30F70)、45%(O45F55)以及100%化肥氮(O100)4个比例梯度进行室内培养试验,研究其对土壤有机碳矿化特征的影响。【结果】有机肥替代化肥氮处理显著降低轻、中度盐碱地土壤<0.25mm水稳性团聚体含量,其中O45F55处理降幅最大,同时,有机肥替代化肥氮处理增加土壤有机碳含量,且随着替代比例增加增幅越大,速效氮、速效磷、速效钾含量在替代率超过15%呈降低趋势。盐碱土壤有机碳矿化累积量随着有机肥替代化肥氮比例的增加而显著增加,培养0~28 d内有机碳矿化率较快,20~60 d内趋于稳定,其中O100处理相比F100处理显著增加,不同程度盐碱土壤累积矿化量由高到低依次为轻度>中度>重度。有机碳累积矿化量与土壤理化因子冗余分析发现,速效氮是影响轻、中度盐碱地土壤有机碳矿化积累量的关键因子,贡献率分别为32.31%和35.23%,pH是影响重度盐碱地土壤有机碳矿化积累量的关键因子,贡献率为25.55%。【结论】O15F85处理不仅改善土壤理化性状,而且能有效降低盐碱土壤有机碳矿化量,生产中可通过调控轻、中度盐碱土壤速效氮含量,抑制重度盐碱地盐分来降低有机碳累积矿化量。
[Objective]In order to reveal the influence mechanism of organic fertilizer replacing chemical fertilizer nitrogen on the carbon cy-cle of saline-alkali soil and evaluate its effect on soil fertility and ecological function,the study analyzed the regulation effect of organic fertil-izer on the mineralization process of organic carbon in saline-alkali soil through field experiments with different substitution ratios.[Method]The light,medium and heavy saline-alkali soil in the Yellow River rrigation area of Ningxia were taken as the research objects.The single ap-plication of chemical fertilizer(F100)was used as the control,and four proportional gradients of 15%(015F85),30%(030F70),45%(045F55)and 100%chemical fertilizer nitrogen(0100)were set up for indoor culture experiment to study its effect on soil organic carbon mineralization characteristics.[Result]The treatment of replacing chemical fertilizer nitrogen with organic fertilizer significantly reduced the soil moderate>severe in mild and moderate saline-alkali soil.Redundancy analysis of cumulative mineralization of organic carbon and soil physical and chemical factors showed that available nitrogen was the key factor affecting the accumulation of organic carbon mineralization in mild and moderate saline-alkali soils,with contribution rates of 32.31%and 35.23%,respectively.pH was the key factor affecting the accu-mulation of organic carbon mineralization in severe saline-alkali soils,with contribution rate of 25.55%.[Conclusion]015F85 treatment not only improves soil physical and chemical properties,but also effectively reduces the amount of organic carbon mineralization in saline-alkali soil.In production,the cumulative mineralization of organic carbon can be reduced by regulating the content of available nitrogen in mild and moderate saline-alkali soil and inhibiting the salt in severe saline-alkali soil.
作者
王生博
纪立东
李龙
WANG Sheng-bo;JI Li-dong;LI Long(College of Agriculture,Ningxia University,Yinchuan 750021,China;Institute of Agricultural Resources and Environment,Ningxia Academy of Agriculture and Forestry Sciences,Yinchuan 750002,China;Ningxia Agriculture and Rural Affairs Department Rural Management Station,Yinchuan 750002,China)
出处
《西南农业学报》
北大核心
2025年第7期1357-1366,共10页
Southwest China Journal of Agricultural Sciences
基金
宁夏回族自治区农业高质量发展和生态保护科技创新示范项目(NGSB-2021-11-07)
宁夏回族自治区重点研发计划(2022BEG02004)。
关键词
引黄灌区
有机肥替代化肥
盐碱土壤
有机碳矿化
Yellow River irrigation area
Organic fertilizer instead of chemical fertilizer
Saline-alkali soil
Organic carbon mineralization
