【作者】 宋付朋；

【导师】 张民；

【作者基本信息】 山东农业大学 ， 土壤学， 2006， 博士

【摘要】 针对长期大量施用磷肥的石灰性土壤中全磷含量大幅度升高的具体情况,鉴于石灰性土壤特定的理化性状及磷酸盐在土壤中的化学行为,致使作物对磷肥的当季利用率过低,从而使大部分磷肥成为难溶态累积在土壤中,已成为丰富的潜在磷素资源。本研究采用化学分析和模拟连作的盆栽试验等方法,探讨了长期施磷的石灰性土壤中磷的不同形态组成、无机磷形态分级方法、各形态磷素的富集与变异特征、磷形态与微量元素形态的关系、耗竭条件下的磷素变异以及石灰性土壤中磷肥的有效性等问题,对阐明这种土壤中磷素的形态组成及其潜在有效性,提高磷肥利用率和开发土壤磷库资源具有重要的现实意义,也为进一步利用土壤难溶态磷和磷肥的施用技术提供理论依据。本论文主要研究结果与结论如下:1、长期施磷石灰性菜园土壤耕层全磷、有效磷、无机磷与有机磷均比粮田富集强烈,有效磷源的无机磷形态含量与植菜年限呈明显的正相关,各形态无机磷含量的垂直分布菜园土壤与粮田土壤存在显著差异,其中溶度较高的Ca2-P、Ca8-P、Fe-P含量菜园土壤表现为表层强烈富集,向下骤减的垂直分布特征,且各层次均显著高于粮田土壤。而粮田土壤虽表层高于下层,垂直分布表现为向下逐渐降低。溶度较高Ca2-P、Ca8-P等与有机质等养分呈极显著的正相关,而与CaCO3含量和pH值的降低呈显著的负相关,随植菜年限的延长,有机质及其它养分含量的提高以及CaCO3含量和pH值的降低也促进了难溶态磷的有效化。2、采用蒋柏藩法对石灰性土壤剖面中无机磷分级形态的分布特征研究发现,剖面中无机磷形态总的变化趋势是二钙磷表层最高,向下逐层降低;在所有层次中均以十钙磷含量最高,其次为八钙磷,其他形态的磷随层次的变化各有差异。石灰性土壤中不同形态的铜、锌、铁、锰各有其分布特性;其分布特性在不同熟化程度的土壤中具有相似性,赋存的主要形态较为一致,但在不同的熟化程度与不同有效磷含量的土壤中其含量比例存在一定的差异。3、在耗竭条件下,土壤中的全磷和有效磷含量均随着连续种植茬数的增多而下降,相对于对照处理,施肥处理耗竭程度大,鸣鸡店土壤施肥比对照处理相对于原土壤全磷量下降了0.074%,哨马营为0.073%;第四茬土壤有效磷与原始土壤有效磷含量相比,更多还原

【Abstract】 For long-term fertilization, the content of total phoshporus rises highly in calcareous soils. Because of the special physical and chemical properties and chemical activity of phosphate, the efficiency of phosphorus fertilization falls excessively, so that most phosphorus fertilizer changing to insoluble forms accumulated into abundant potential phosphate resource in soil. The objectives of this research were to analyze the fractionation and the availability of phosphorus in soil and to enhance the efficiency of phosphate fertilizer and to explore the phosphate resourse in soil, at the same time, to provide a scientific basis for utilization of insoluble phosphate fertilizer and technology of fertilization. The research discussed the different forms of phosphorus in calcareous soil, different fractionation methods, the enrichment and characteristics of different phoshorus forms, the correlation between the forms of phoshorus and microelement, variation of phoshorus at the exhausting condition and the availablity of phosphorus fertilizer in calcareous soils. The main results and conclusions were as follows:1. The amount of total P, availabile P, inorganic P, and organic P significiantly increased in calcareous vegetable soil more than those in calcareous crop soil for long-term fertilization. The amount of availibile inorganic P characterized positive correlation with years of planting significiently. The vertical distribution of different inorganic phosphorus forms in vegetable soil differed from these in crop clutivated soil significiantly. Different forms of phosphorus in cultivated soil characterized enrichment in surface horizon and falled down from the cultivated soil in the pedon abruptly. The content of Ca2-P, Ca8-P, Fe-P in vegetable soil characterized with enrichment in surface horizon and falled down from the cultivated soil in the pedon abruptly, and these of different horizons in vegetable soil were higher than those in crop soil. Although hose of A horizon were higher than that of lower horizon in the crop soil, vertical distribution of Ca2-P, Ca8-P, Fe-P in the soil profile charactered with falling down gradually. Diffluent P fractions such as Ca2-P、Ca8-P were highly correlated with the nutrition更多还原