摘要
为探明长期不同施肥下黄壤稻田锌形态变化规律及对土壤锌有效性的影响,以设立于1995年的长期定位施肥试验为对象,对比分析不施肥(CK)、氮钾肥配施(NK)、氮磷钾肥配施(NPK)、单施有机肥(M)、1/2有机肥替代1/2化学氮磷肥及全部化学钾肥(0.5MNP)、全量有机肥化肥配施(MNPK)6个处理耕层土壤有效锌及锌形态时序变化规律,并采用相关分析和通径分析方法分析不同形态锌与有效锌的关系。结果表明,NK处理土壤有效锌和锌活化系数随试验年限增加呈降低趋势,其中锌活化系数线性拟合方程达显著水平,年下降速率为0.05个百分点。与NK处理相比,2019年,NPK处理土壤有效锌和锌活化系数分别提高了44.1%和1.49个百分点,弱酸可溶态锌和可还原态锌含量分别提高了15.9%和5.3%。施用有机肥处理土壤有效锌和锌活化系数随试验年限增加呈不断增加趋势,年增长速率分别为0.074~0.1244 mg·kg^(-1)和0.032~0.063个百分点。与NPK处理相比,施用有机肥的处理2019年土壤有效锌和锌活化系数分别显著提高了6.3%~22.6%和0.68~1.47个百分点,弱酸可溶态锌、可还原态锌、可氧化态锌含量分别显著提高了33.6%~84.0%、32.5%~47.4%、25.5%~36.3%,其占比分别提高了0.6~1.3个百分点、1.7~3.4个百分点、1.2~7.3个百分点,残渣态锌占比降低了3.6~12.0个百分点。相关分析表明,土壤有效锌与弱酸可溶态锌、可还原态锌、可氧化态锌呈极显著正相关,与残渣态锌呈极显著负相关。通径分析结果表明,弱酸可溶态锌对有效锌直接通径系数最大,有显著直接正效应,残渣态锌对有效锌有显著直接负效应,可还原态锌和可氧化态锌通过间接影响弱酸可溶态锌对有效锌有较强间接正效应。综上,弱酸可溶态锌是黄壤稻田有效锌的主要来源,可还原态锌和可氧化态锌是有效锌的重要缓存库。农业生产中,可通过合理施用有机肥促进锌向弱酸可溶态锌、可还原态锌、可氧化态锌转化,避免其向残渣态锌累积来提高土壤锌有效性。
【Objective】To investigate the variation of zinc(Zn)speciation in yellow paddy soil under different long-term fertilization and its effect on available Zn,a field experiment was designed in 1995.【Method】There were six treatments:the control(no fertilizer,CK),P deficiency(NK),balanced application of chemical N,P and K fertilizer(NPK),single manure(M),lower organic and inorganic fertilizer combination treatments(0.5 MNP),and higher organic and inorganic fertilizer combination treatments(MNPK).The change process of soil available Zn and the temporal variation of different forms of Zn were studied.Also,the relationship between different forms of Zn and available Zn was analyzed with correlation and path analyses.【Result】The results showed that the available Zn and Zn activation coefficient of soil with NK treatment decreased with the increase of experimental years.During this time,the linear fitting formula of the Zn activation coefficient reached a significant level,and the annual growth rate was–0.05 percentage points.Compared with NK treatment,the available Zn and Zn activation coefficient of soil with NPK treatment increased by 44.1%and 1.49 percentage points,respectively in 2019.Also,the contents of weak acid soluble Zn and reducible Zn increased by 15.9%and 5.3%,respectively.For treatments with organic fertilizer,the available Zn and Zn activation coefficient of soil increased linearly with the increase of experimental years,and the annual growth rate was 0.074–0.1244 mg·kg^(-1) and 0.032–0.063 percentage points,respectively.Compared with NPK treatment in 2019,the available Zn and Zn activation coefficient of soil in the manure treatments increased significantly by 6.3%–22.6%and 0.68–1.47 percentage points,respectively.For these treatments,the contents of weak acid-soluble,reducible,and oxidizable Zn increased significantly by 33.6%–84.0%,32.5%–47.4%,and 25.5%–36.3%,respectively.In addition,the proportions of weak acid-soluble,reducible,and oxidizable Zn increased significantly by 0.6–1.3,1.7–3.4,and 1.2–7.3 percentage points,respectively.On the contrary,the proportion of residual Zn was observed to decrease by 3.6–12.0 percentage points.Correlation analysis showed that soil available Zn was significantly positively correlated with weak acid-soluble,reducible,and oxidizable Zn,but significantly negatively correlated with residual Zn.Path analysis results showed that the direct path coefficient of weak acid-soluble Zn was the largest and had a significant direct positive effect on available Zn,residual Zn showed a significant direct negative effect on available Zn,while reducible and oxidizable Zn indirectly affected weak acid soluble Zn and had a strong indirect positive effect on available Zn.【Conclusion】The weak acid-soluble Zn was the main source of available Zn in yellow paddy soil,while reducible and oxidizable Zn were the important cache database of available Zn.In agricultural production,the soil Zn efficiency could be improved by applying organic fertilizer reasonably to promote the transformation of Zn to weak acid-soluble,reducible,and oxidizable Zn,and avoid the accumulation of Zn in the residual state.
作者
刘彦伶
李渝
蒋太明
张雅蓉
黄兴成
朱华清
杨叶华
张萌
张文安
张艳
LIU Yanling;LI Yu;JIANG Taiming;ZHANG Yarong;HUANG Xingcheng;ZHU Huaqing;YANG Yehua;ZHANG Meng;ZHANG Wen’an;ZHANG Yan(Institute of Soil and Fertilizer,Guizhou Academy of Agricultural Sciences,Guiyang 550006,China;Scientific Observing and Experimental Station of Arable Land Conservation and Agriculture Environment(Guizhou),Ministry of Agriculture and Rural Affairs,Guiyang 550006,China;Guizhou Academy of Agricultural Sciences,Guiyang 550006,China)
出处
《土壤学报》
CAS
CSCD
北大核心
2023年第1期258-268,共11页
Acta Pedologica Sinica
基金
国家自然科学基金项目(32060302,31860132)
贵州省科学技术基金项目(黔科合基础[2018]1154)资助。
关键词
黄壤稻田
长期施肥
有效锌
锌形态
通径分析
Yellow paddy soil
Long-term fertilization
Available Zn
Zn form
Path analysis