冻融循环作用对黑土无机磷各形态含量模拟研究

发布时间：2018-05-14 20:00

本文选题：冻融作用 + 无机磷形态　；参考：《沈阳农业大学》2016年硕士论文

【摘要】：东北黑土区平均日、年温差较大,春季解冻期冻融交替频繁持续时间较长,该时期冻融作用对土壤磷素转化、迁移和流失有较大影响。磷素是作物生长所需要的重要微量元素,同时也决定着土壤生产力。无机磷是土壤磷素主要组成部分,无机磷各形态含量是土壤有效磷含量多少的决定性因素。冻融作用是影响无机磷赋存与转化重要因素之一,对土壤磷素的有效性及其含量有着直接或间接的影响。磷肥施入土壤后发生了系列的物理化学过程进而影响其对作物的有效性,本试验采用室内模拟春季解冻期冻融环境,以东北黑土为研究对象,研究冻融循环次数(FTC)、土壤含水率(W)和土壤有效磷背景值(APb)对铝磷(A1-P)、铁磷(Fe-P)、闭蓄态磷(O-P)和钙磷(Ca-P)含量的影响,根据上述研究得出无机磷形态在三种因素条件下的变化规律以及与有效磷Olsen-P的线性关系,得出作物生长的磷肥需求量及所需的最适土壤含水量,以及土壤磷素状况以及潜在的环境风险。取得的主要结论如下：(1)冻融循环次数(FTC)对四种无机磷形态的影响冻融循环过程中,0～5次循环无机磷各形态含量变化较为剧烈,随着循环次数增加,其含量变化逐渐趋于平缓,且相邻冻融循环处理之间各形态大部分都达到显著性差异。方差分析得出,冻融循环次数对无机磷各形态绝对含量增量的影响占主导地位。(2)土壤含水率(W)对四种无机磷形态的影响冻融循环过程中,四种无机磷形态含水率为40%、50%和60%时变化规律较为相近。含水率为40%时冻融前后绝对含量差值变化最大,Al-P、 Fe-P和Ca-P分别为6.88 mg·kg-1、8.18 mg·kg-1和7.5 mg·kg-1,含水率为30%时,闭蓄态磷O-P绝对含量差值变化最大,为36.3 mg·kg-1。方差分析得出,在整个冻融循环过程中,含水率除对闭蓄态磷O-P没有达到显著影响外,对其他三种无机磷形态都达显著性影响。(3)土壤有效磷背景值(APb)对四种无机磷形态的影响冻融循环过程中,增加有效磷背景值会直接增加四种无机磷形态绝对含量,冻融循环后无机磷各形态绝对含量大小为O-PFe-PAl-PCa-P。有效磷背景值在40 mg·kg-1～100 mg·kg-1区间规律性明显,在80 mg·kg-1时冻融前后含量差值变化最大Al-P、Fe-P、O-P和Ca-P分别为9.37 mg·kg-1、5.44 mg·kg-1、60.77 mg·kg-1和7.44 mg.kg-1。方差分析得出有效磷背景值对无机磷各形态绝对含量的影响占主导地位。(4)无机磷各形态有效性四种无机磷形态的含量与有效磷的含量进行相关分析得出无机磷各形态有效性大小为Al-PFe-PCa-PO-P;在相关分析的基础上结合通径分析得出,Al-P和Fe-P为有效磷源,并且直接影响有效磷含量；闭蓄态磷O-P和Ca-P通过Al-P间接影响有效磷含量。Olsen-P (Y)与有效磷源Al-P (X1)、Fe-P(X2)得出的线性关系为：Y= (0.021X2+0.228) X1-(0.028X2-0.149) X2-(0.104X2-3.486X+36.994)。
[Abstract]:In the black soil area of Northeast China, the average daily temperature difference is large, the annual temperature difference is large, and the alternate freezing and thawing period in spring is longer. The freezing and thawing process in this period has a great influence on the transformation, migration and loss of soil phosphorus. Phosphorus is an important trace element for crop growth and also determines soil productivity. Inorganic phosphorus is the main component of soil phosphorus, and the content of inorganic phosphorus forms is the decisive factor of soil available phosphorus content. Freezing and thawing is one of the important factors affecting the storage and transformation of inorganic phosphorus, which has a direct or indirect effect on the availability and content of phosphorus in soil. A series of physical and chemical processes occurred after the application of phosphate fertilizer into the soil, which affected the effectiveness of the plant. In this experiment, the freezing and thawing environment during the spring thawing period was simulated in laboratory, and the black soil in the northeast of China was taken as the research object. The effects of freeze-thaw cycles (FTC), soil moisture content (W) and soil available phosphorus background value (APB) on the contents of Aluminophosphorus (A1-PN), Fe (P) (P), P (O) (P), and Ca (P) (Ca-P) were studied. According to the above study, the variation rule of inorganic phosphorus form under three factors and the linear relationship between inorganic phosphorus form and available phosphorus Olsen-P were obtained, and the demand of phosphorus fertilizer for crop growth and the optimum soil water content were obtained. And soil phosphorus status and potential environmental risks. The main conclusions are as follows: (1) the effects of freeze-thaw cycles (FTC) on the four inorganic phosphorus forms during freeze-thaw cycles, the contents of inorganic phosphorus in five cycles of freeze-thaw cycles change sharply, and with the increase of cycling times, the contents of inorganic phosphorus change gradually. And most of the forms of the adjacent freeze-thaw cycle treatment reached significant difference. The variance analysis showed that the effect of freezing and thawing cycle times on the absolute content increment of inorganic phosphorus was dominant. (2) soil moisture content (W2) affected the four inorganic phosphorus forms during freeze-thaw cycle. The water content of the four inorganic phosphorus forms is 40% and 60% respectively. When the water content was 40, the difference of absolute content of Al-P, Fe-P and Ca-P was 6.88 mg / kg ~ (-1), 8.18 mg / kg-1 and 7.5 mg / kg ~ (-1), respectively. When the water content was 30 mg / L, the difference of absolute content of closed storage phosphorus O-P was the biggest (36.3 mg / kg ~ (-1). The variance analysis shows that, during the whole freeze-thaw cycle, the moisture content has no significant effect on the closed storage phosphorus O-P. Effect of soil available phosphorus background value on the four inorganic phosphorus forms; during freeze-thaw cycle, the absolute content of four inorganic phosphorus forms increased directly by increasing the background value of available phosphorus. The absolute content of inorganic phosphorus was O-PFe-PAl-PCa-P after freeze-thaw cycle. The background value of available phosphorus was regular in the range of 40 mg kg-1~100 mg kg-1, and the maximum variation of content difference between freezing and thawing was 9.37 mg / kg ~ (-1) mg 路kg ~ (-1) ~ 5.44 mg 路kg ~ (-1) ~ (-1) kg-1 and 7.44 mg 路kg ~ (-1) 路kg ~ (-1), respectively. The analysis of variance shows that the background value of available phosphorus has a dominant effect on the absolute content of inorganic phosphorus forms. (4) the contents of four kinds of inorganic phosphorus forms and the contents of available phosphorus forms are related to each other. On the basis of correlation analysis and path analysis, it was found that Al-P and Fe-P were effective phosphorus sources. The linear relationship between closed phosphorus O-P and Ca-P indirectly affecting available phosphorus content through Al-P and available phosphorus source Al-P X _ (1) P _ (1) O _ (2) and Fe _ (PX _ (2) is as follows: (1) Y = 0.021X _ (2 0.228) X _ (1) ~ (0.028) X _ (2-0.149) X2-(0.104X2-3.486X 36.994m) (P = 0. 021X _ (2) 0.228) (P = 0. 021X _ (2) 0.228) (P = 0. 021).
【学位授予单位】：沈阳农业大学
【学位级别】：硕士
【学位授予年份】：2016
【分类号】：S153.6

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