长期施肥对旱地红壤微团聚体磷素有效性的影响  

Effects of Long-term Fertilization on Availability of Micro-aggregate Associated Phosphorus in Upland Red Soil

作　　者：周亦靖 牛犇 李欢 王艳玲[1] ZHOU Yi-jing;NIU Ben;LI Huan;WANG Yan-ling(College of Applied Meteorology,Nanjing University of Information Science and Technology,Nanjing 210044,China;Changwang College,Nanjing University of Information Science and Technology,Nanjing 210044,China)

机构地区：[1]南京信息工程大学应用气象学院,江苏南京210044 [2]南京信息工程大学长望学院,江苏南京210044

出　　处：《土壤通报》2023年第1期89-99,共11页Chinese Journal of Soil Science

基　　金：国家自然科学基金项目(42077087)资助。

摘　　要：【目的】土壤微团聚体是磷素储存与周转的重要载体,明确长期施肥下旱地红壤微团聚体中赋存磷素的形态及其生物有效性,为磷肥的高效合理施用提供理论依据。【方法】以位于鹰潭农田生态系统国家野外科学观测研究站院内的长期肥料定位试验(1988~2014)为依托,分别以有机无机配施区的1/2 NPK(CK)、低量NPK+稻秆(RS)与低量NPK+猪厩肥(PM)处理及无机肥区的NK与NPK处理的旱地红壤为研究材料,采用水分散-吸管法逐级提取了土壤中0.25~0.05 mm、0.05~0.01 mm、0.01~0.005 mm与<0.005 mm粒级微团聚体,对比分析了各粒级微团聚体中全磷、有效磷及磷活化系数的变化差异。基于土壤磷素分级结果,分析了旱地红壤中大小粒级微团聚体中极有效磷、中等有效磷及非有效磷对长期施肥的响应。借助于结构方程模型探讨了微团聚体中各形态磷、磷活化系数、颗粒组成、有机质、铁铝氧化物等因子与有效磷的互应关系。【结果】长期配施猪粪可以显著增加旱地红壤各粒级微团聚体中全磷、有效磷、磷活化系数及极有效磷、中等有效磷及非有效磷的含量,且<0.005 mm粒级微团聚体中的各组分磷增加比例最多,而配施稻秆只可显著降低0.01~0.005 mm粒级微团聚体中各组分磷含量。与NPK处理相比,长期不施磷肥的NK处理中各粒级微团聚体中各组分磷含量均显著降低,且0.05~0.01 mm粒级中的降低比例最大,还可以显著降低0.25~0.05 mm与0.05~0.01 mm微团聚体的磷活化系数,但增加0.01~0.005 mm与<0.005 mm粒级的磷活化系数。结构方程模型拟合结果表明,长期施肥的旱地红壤微团聚体中无机磷组分是影响有效磷的正向因子,而有机磷组分则是负向影响因子;逐步回归分析发现NaHCO3和HCl提取态的无机磷组分则是影响旱地红壤磷活化系数的主要因子。【结论】在施用化肥的基础上配施有机肥、尤其是配施猪粪,可以显[Objective] Soil micro-aggregates are the important carriers of phosphorus(P) storage and turnover. To clarify the form and bioavailability of soil microaggregate associated P in upland red soil under long-term fertilization can provide the theoretical basis for the efficient and rational application of P fertilizers. [Method] Based on the longterm fertilization experiment(1988-2014) located at the Red Soil Ecological Station in Yingtan, Jiangxi Province,China, total 15 soil surface samples(0-15 cm) were collected from the combined application of organic-inorganic fertilizer plot(Treatment 1/2 NPK(CK), low quantity NPK + rice straw(RS) and low quantity NPK + pig manure(PM)) and the single application of chemical fertilizer plot(Treatment NPK and NK), respectively. Soil microaggregate size in 0.25-0.05 mm, 0.05-0.01 mm, 0.01-0.005 mm and < 0.005 mm were sequentially extracted by pipette method after the water disperses. The changes of soil total P(TP), Bray-P and the P activation coefficient(PAC) in various soil micro-aggregates were analyzed, and the extremely available P(EAP), medium available P(MAP) and non-available P(NAP) of micro-aggregates response to the long-term fertilization were also analyzed based on the results of soil P fractionation. And the relationships between the soil P fractionation, PAC, particle composition, soil organic matter, iron-aluminum oxides and Bray-P were discussed based on the structural equation model. [Result] Long-term combined application of pig manure can significantly increase the TP, Bray-P, PAC and EAP, MAP, NAP in various micro-aggregates, and the increase proportion of them in < 0.005 mm micro-aggregate was higher, but the combined application of rice straw only can significantly decrease the P content of 0.01-0.005mm micro-aggregate. Compared with NPK treatment, NK treatment can significantly decrease the contents of all P fractions in various micro-aggregates, and also can significantly decrease the PAC of 0.25-0.05 mm and 0.05-0.01mm micro-aggregates, but significantl

关 键 词：长期施肥 微团聚体 磷分级 磷有效性 结构方程模型 

分 类 号：S152.4[农业科学—土壤学] S153.6[农业科学—农业基础科学]