摘要
在湖北省武穴市长期定位试验的基础上,取不同施肥处理（施氮磷钾处理/NPK,氮磷钾-秸秆配施处理/NPKS）和荒地（HD）的土样,分离其耕层土壤（0～20 cm）不同粒级（<2000 nm与450～2000、100～450和25～100 nm三个粒级）的土壤颗粒,并分析各粒级颗粒中粘粒矿物组合和氧化物的差异,揭示不同施肥措施下农田土壤颗粒中粘粒矿物的变化特征。结果表明,不同施肥处理土壤粘粒矿物的组成一致,均以高岭石为主,并都含有蛭石、HIV（1.4 nm过渡矿物）和伊利石,且随颗粒粒径减小矿物从2:1型向1:1型过渡;与荒地土壤相比,施氮磷钾处理中伊利石和蛭石减少,HIV增加,而氮磷钾-秸秆配施处理中则是伊利石减少,蛭石和HIV增加。随粒径减小,3种土壤颗粒中SiO2和Fe2O3含量逐渐降低,Al2O3含量逐渐增加,其中各粒级颗粒的硅铝率和硅铁铝率也逐渐降低;与荒地土壤比,施氮磷钾和氮磷钾-秸秆配施处理各粒级颗粒的元素组成无明显变化,而硅铝率和硅铁铝率却有明显提高。3种土壤颗粒中游离态铁、铝含量的顺序为HD>NPKS>NPK,与铁游离度的变化规律一致,但非晶形铁、铝含量和铁的活化度变化不明显。各形态铁、铝氧化物的含量均随粒径减小而逐渐增大,与铁的游离度和活化度的变化规律一致。
On the basis of the long term positioning experiment in the Wuxue City of Hubei Province, the mineral assemblages and chemical compositions of clay minerals in various particle fractions（<2000, 450～2000, 100～450 and 25～100 nm） of different fertilizer treated（by nitrogen, phosphate, and potassium fertilizers（NPK）, or by nitrogen, phosphate, and potassium fertilizers coupled with straw ash（NPKS）） soils and uncultivated soils（HD） from the long term positioning experiment field have been sampled and investigated in this paper to reveal the variation characteristics of clay minerals in farmland soil particles under various treatments of fertilization. The results indicate that the different fertilizer treated soils have generally similar compositions of clay minerals, with major kaolinite and minor vermiculite, HIV（1.4 nm sized intergradient mineral）, and illite. With the decrease of the particle size in soils, clay minerals in the soils are gradually transited from the 1:1 to 2:1 types. Comparing with uncultivated soil, the NPK treated soil contains lower contents of illite and vermiculite but higher contents of HIV, while the NPKS treated soil contains lower content of illite but higher contents of vermiculite and HIV. With the decrease of soil particle size, the SiO2 and Fe2O3 contents of 3 kinds of soils are gradually are decreased, but the content of Al2O3 is increased. Especially, with the decrease of particle size, the SiO2/Al2O3 and SiO2/（Al2O3+Fe2O3） ratios are decreased gradually in three kinds of soil particles. Comparing with the uncultivated soil, the NPK and NPKS treated various sized soil particles have no significant changes in the elemental composition, but have significantly higher SiO2/Al2O3 and SiO2/（Al2O3+Fe2O3） ratios. The free iron and aluminum contents of three kinds of soil particles are subsequently decreased from the HD, then the NPKS, to the NPK. This is consistent with the change of iron freeness. There is no obvious relationship between the amorphous
出处
《矿物学报》
CAS
CSCD
北大核心
2018年第5期563-571,共9页
Acta Mineralogica Sinica
基金
国家自然科学基金项目(批准号:41271252)
公益性行业专项基金(编号:201503123)
关键词
长期施肥
土壤颗粒
粘粒矿物
氧化物组成
long-term fertilization
soil particles
clay minerals
oxide composition
