植酸在不同沉积物、矿物材料和土壤中的行为研究

发布时间：2018-03-13 15:51

本文选题：植酸　切入点：吸附　出处：《华中农业大学》2016年博士论文　论文类型：学位论文

【摘要】：随着我国养殖业的高速发展,含有丰富植酸的禽畜废弃物大量进入环境。同时,工业的高速发展和不合理施肥导致我国土壤中重金属的污染问题日益严峻,造成农田荒芜、水体污染的现象屡见不鲜,严重制约了我国农业和社会经济的可持续发展。植酸作为优良的螯合剂和抗氧化剂在食品、化工和重金属污染治理方面表现着不可忽视的作用。随着科学技术水平的不断进步,植酸的测定技术日臻成熟为研究植酸在环境中的行为提供了有力手段。近年来,植酸与环境介质中重金属的作用已成为研究热点。本研究通过野外调查,探讨了典型农田和淡水生态系统中植酸酶的分布特点,磷素及植酸的分布行为和赋存形态；通过实验室批处理实验,研究了植酸在矿物材料和土壤界面的吸附解吸特性及其重金属结合形态的变化特征；采用小麦土壤盆栽试验,研究了As污染土壤上植酸对植物体抗氧化酶系统和重金属在植物体内的分布变化的影响。获得的主要结果如下：(1)自然湖泊梁子湖不同沉积物中,IP (Inorganic Phosphorus)含量占TP (Total Phosphorus)的40-71%,而OP (Organic Phosphorus)的含量比较低,仅占13%-45%。梁子湖入水口处IP的含量分布表现为,0.8 m以上沉积物部分为HCl-P≈NaOH-P,而0.8 m以下沉积物部分为HCl-PNaOH-P,而在出水口的趋势相反。OP组分在梁子湖和月湖中都表现为MLOP MROPLOP.(2)分析磷素在不同年代沉积物中的积累特征发现,在2ka.BP以来TP和植酸含量不断增加,在2-4 ka.BP之间先迅速增加而后趋于稳定,而8.6 ka.BP之前(4.5m以下)磷的含量处于较低水平,这一结果表明,沉积物中TP和植酸的含量变化可以较准确的反映沉积物中磷的输入历史。(3)在城市湖泊月湖中,表层沉积物中TP的含量居民生活干扰区(YH1)明显高于非生活干扰区(YH2)。月湖沉积物中IP的NaOH-P基本相当,但在居民生活干扰区表层HCl-P含量明显高于非干扰区。月湖沉积物中OP主要是MLOP,各组分表现为MLOPLOP, MROP。月湖沉积物中植酸含量和植酸酶的活性随深度的增加而逐渐降低,在表层土壤中(1m以上)生活干扰区植酸含量和植酸酶的活性均大于非干扰区。研究结果还表明在城市湖泊中的磷主要富集于表层沉积物中。(4)农田土壤剖面磷素的分布特征分析表明,农田土壤磷素均表现出强烈的淋溶并在土层中、深层积累的特征。梁子湖周边两种土壤(水稻土和旱地油菜)剖面的磷素积累特征基本一致,表现为磷素分别在表层(0.4m以上)和下层(1.4m以下)积累,而水稻土下层磷素积累明显高于油菜田土壤。与沉积物不同,梁子湖区土壤IP含量NaOH-PHCl-P,而Q4母质发育的2种菜地土壤(长江沿岸)为HCl-P NaOH-P。与湖泊沉积物有机磷组分变化类似,土壤的有机磷亦表现出MLOPLOP, MROP的含量,其中MLOP含量变幅较大,是土壤有机磷的活跃形态。但各种土壤LOP和MROP的含量比湖泊沉积物显著提高。值得注意的是,农田土壤植酸含量明显低于湖泊沉积物的植酸含量,但植酸酶活性与湖泊沉积物基本相当。(5)植酸与重金属以及矿物材料之间作用的批处理研究表明,植酸、重金属离子和矿物材料相互作用显著影响环境中重金属的界面行为。四种矿物材料(钢渣、含铁锰矿、蒙脱石、针铁矿)对3种重金属(Cd、As、Zn)的最佳吸附温度为25℃,吸附饱和时间为24h,四种矿物中钢渣和铁锰矿对重金属的吸附效果最佳。植酸与Cd和As的络合吸附过程降低了重金属在矿物材料表面的吸附作用,其中对As、Cd吸附影响最大的蒙脱石,植酸浓度为2mM时蒙脱石对As和Cd的吸附率分别降低了100%和53%。而植酸与Zn的络合沉淀过程反而增加了Zn与矿物材料的吸附作用,在四种矿物材料中,植酸的添加增加了矿物对Zn的吸附。(6)植酸、重金属及不同类型土壤之间的相互作用研究发现,添加植酸降低四种土壤(红壤、灰潮土、褐土、黑土)对重金属Cd和As的吸附,其中以红壤和灰潮土最为明显；同时植酸对四种土壤重金属的解吸率最高可达98.8%。随着添加植酸浓度的上升,Zn的吸附率升高而解吸率下降,且低于Cd和As的解吸率。(7)培养试验结果表明,加入植酸后,在酸性红壤和黑土中,四种金属As、Cd、Pb和Zn中随着培养时间的延长有效态含量逐渐升高,而碱性土壤灰潮土和褐土中四种重金属的有效态逐渐下降。重金属形态分析结果表明,Cd,Pb,Zn以可还原态和可交换态变化较大,而As以专性吸附、非专性吸附和残渣态的变化最大。(8)在As污染土壤中,添加植酸可促进小麦生长。小麦体内As的累积随着植酸的添加有不同程度的降低(18.8%-98.9%)。添加植酸还显著降低小麦叶片中MDA含量。
[Abstract]:With the rapid development of aquaculture in China, rich in phytic acid livestock waste into environment. At the same time, the rapid development of industry and the unreasonable fertilization led to the problem of heavy metal pollution in the soil of our country is becoming increasingly serious, resulting in barren farmland, water pollution phenomenon is not uncommon, seriously restricting the sustainable development of our agriculture and social economy excellent. Phytic acid as chelating agent and antioxidant in food, performance can not be ignored in chemical industry and heavy metal pollution. With the continuous progress of science and technology, phytic acid determination technology provides a powerful means for the maturity of phytic acid behavior in the environment. In recent years, heavy metals and phytic acid in environmental media the role has become a hot research topic in this research. Through field investigation, discusses the distribution characteristics of typical farmland and phytase in freshwater ecosystem, phosphorus and plant The distribution behavior and speciation of acid; through laboratory batch experiments of phytic acid in combination with morphological change characteristics in the adsorption and desorption of heavy metals and mineral materials and soil interface; the wheat soil pot experiment to study the effects of As on soil pollution of phytic acid on plant antioxidant enzymes and the distribution of heavy metals in plants of the change. The main results are as follows: (1) the natural lake Liangzi Lake Sediments in different IP (Inorganic, Phosphorus) TP (Total Phosphorus) in 40-71% OP (Organic Phosphorus), and the content is relatively low, accounting for only 13%-45%. content distribution in entrance IP, above 0.8 m sediment part is HCl-P about NaOH-P, below the 0.8 m sediment part is HCl-PNaOH-P, and the water outlet opposite to the trend of the.OP component in the lake in Liangzi Lake and had MLOP MROPLOP. (2) Analysis of the characteristics of phosphorus accumulation was found in different age sediments, in 2ka.BP since TP and phytic acid content increased, in 2-4 ka.BP increased rapidly at first and then tended to be stable, and before 8.6 ka.BP (below 4.5m) phosphorus content in the low level, the results show that the content changes of TP and phytic acid in sediment the input can accurately reflect the history of phosphorus in the sediments. (3) in the city of Lake Lake, surface sediments and the content of TP in the living area interference (YH1) was significantly higher than that of non life interference area (YH2). NaOH-P based IP in the lake sediments, but residents in the surface life interference area HCl-P content was significantly higher than that of non interference area. Lake sediment OP MLOP is the main component, the performance of the MLOPLOP, increasing phytic acid content and phytase activity in MROP. lake sediments with depth gradually decreased, in the surface soil (1m) dry life Rejection zone phytic acid content and phytase activity were higher than in non disturbing region. The results also show that in the city of lake of phosphorus enriched in the surface sediments. (4) the soil profile of phosphorus distribution analysis showed that soil phosphorus showed strong leaching in soil layer, characteristic of deep accumulation. Two kinds of soil surrounding Liangzi Lake (paddy soil and upland rape) section of the phosphorus accumulation characteristics of consistent performance for phosphorus in the surface (above 0.4m) and lower (below 1.4m) and lower accumulation of paddy soil phosphorus accumulation was significantly higher than that of the oil and sediment of different vegetable soil. Soil IP NaOH-PHCl-P, Liangzihu district the content of Q4, and the development of 2 kinds of soil parent materials (NaOH-P. and HCl-P along the Yangtze River) for lake sediment organic phosphorus fractions were similar, organic phosphorus in soil also showed MLOPLOP, MROP content, MLOP content varied greatly That is the active soil organic phosphorus forms. But the content of various soil LOP and MROP ratio in lake sediments increased significantly. It is worth noting that the phytic acid content in farmland soil was significantly lower than the phytic acid content in lake sediments, but the phytase activity and lake sediments is quite basic. (5) a batch study of interaction of phytic acid and heavy metals and mineral materials show that phytic acid, the interaction between heavy metal ions and mineral materials significantly affect the interfacial behavior of heavy metals in the environment. Four kinds of mineral materials (steel slag, iron ore, montmorillonite, goethite) of 3 heavy metals (Cd, As, Zn) the best adsorption temperature is 25 DEG C, the saturated adsorption time is 24h, the adsorption effect of four for manganese slag and iron minerals in the heavy metal complexation. The best adsorption process of phytic acid and Cd and As decreased the adsorption of heavy metals in the mineral surface, in which the As Cd, the greatest impact of montmorillonite adsorption Phytic acid, when the concentration of 2mM montmorillonite adsorption on As and Cd rate were decreased by 100% and 53%. and Zn and phytic acid precipitation and complexation process but increased the adsorption of Zn and mineral materials, in four kinds of mineral materials, adding phytic acid to increase the adsorption of Zn minerals. (6) study on Phytic acid interaction between different types of heavy metals in the soil and found that adding the phytic acid of four kinds of soil decreased (red soil, grey fluvo aquic soil, cinnamon soil, black soil) adsorption of heavy metals Cd and As, with red and grey fluvo aquic soil was the most obvious; at the same time of phytic acid on four kinds of soil heavy metal desorption rate of up to 98.8%. with the increase of adding phytic acid the concentration of Zn, the adsorption rate increased while desorption rate decreased, and lower than the desorption of Cd and As. (7) the results showed that adding phytic acid, in acid red soil and black soil, four kinds of metal As, Cd, Pb and Zn with the training time available content Increased gradually, and the effective state of four kinds of heavy metals in alkaline soil and cinnamon soil in grey fluvo aquic soil decreased gradually. Heavy metal speciation analysis showed that Cd, Pb, Zn in reducible and exchangeable changes greatly, while As with specific adsorption, change of non specific adsorption and residual maximum (8). In As polluted soil, adding phytic acid can promote the growth of wheat. The accumulation of As in Wheat with adding phytic acid decreased (18.8%-98.9%). Adding phytic acid also significantly reduced MDA content in wheat leaves.

【学位授予单位】：华中农业大学
【学位级别】：博士
【学位授予年份】：2016
【分类号】：X132;S151.9

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