【作者】 贺婧；

【导师】 关连珠；

【作者基本信息】 沈阳农业大学 ， 农业环境与生态， 2012， 博士

【摘要】 我国北方地区分布着大面积的石灰性土壤（Calcareous Soil）,而且大部分是重要的农田土壤。由于土壤剖面中含有不同数量的碳酸钙或碳酸氢钙等石灰性物质，一方面可以左右着土壤中植物营养物质的转化和存在形态，影响植物营养元素的有效性，另一方面也必将影响外源进入到土壤中的各种污染物质的化学行为和生物活性。本项研究以不同碳酸钙含量石灰性土壤为供试材料，在分析其基本性质的基础上，重点研究土壤中碳酸钙对外源重金属和一些有机污染物吸附容量和吸附特性的影响，以期为明确土壤中碳酸钙的环境效应，进一步评断含有不同数量碳酸钙的石灰性土壤的环境容量和承载外源污染物的能力提供数据参考和理论依据。研究结果表明：（1）供试石灰性自然土壤的pH值在7.78⁸.18之间，碳酸钙含量在30.51g.kg^-1100.23g.kg^-1之间，有机质、粘粒差异不显著。供试培养石灰性土壤pH值在7.02⁸.42之间，碳酸钙含量在8.61²27.94之间，有机质及粘粒含量均随着碳酸钙含量的增加而减少。碳酸钙对不同酶活性影响不同，低碳酸钙含量（本试验为3%以内）对碱性磷酸酶活性有促进作用，高碳酸钙含量（本试验为3%以上）则对碱性磷酸酶活性起抑制作用；低碳酸钙含量（本试验为5%以内）对脲酶及过氧化氢酶活性起促进作用，高碳酸钙含量范围内（本试验为5%以上）起抑制作用；碳酸钙对转化酶活性有抑制作用。（2）土壤pH与碳酸钙含量呈极显著非线性相关关系。在碳酸钙含量较低时(<89.91g.kg^-1)，pH随碳酸钙含量的增加而增加较快，但随着碳酸钙含量的继续增加，pH变化较慢，直至达到平衡。（3）石灰性土壤对外源重金属铅及铜具有很大的吸附容量，对重金属铅的最大吸附量可以达到11234mg.kg^-117513mg.kg^-1，对铜的最大吸附量可以达到9856mg.kg^-113039mg.kg^-1之间。而且对重金属铅和铜的最大吸附量随着土壤碳酸钙含量的增加而增加。石灰性土壤对被吸附重金属的吸附结合能很强，被土壤吸附铅的解吸率只有不到2%，吸附铜的解吸率也只有不到10%，而且土壤中碳酸钙含量越高，被吸附重金属的解吸率越小，说明土壤中的碳酸钙含量对于固持外源重金属具有重要意义。（4）外源重金属铅、铜进入石灰性土壤后，石灰性土壤中各形态铅、铜含量及所占比例均发生变化。可交换态及残渣态所占比例均下降，而碳酸盐态、铁锰氧化态及有机态所占比例均不同程度的有所增加，并有随着碳酸钙含量的增加可交换态及有机态有向碳酸盐结合态及铁锰氧化态转化的趋势，这是随碳酸钙含量增加石灰性土壤对重金属吸附容量增加的重要原因。（5）不同碳酸钙含量石灰性土壤对苯酚的最大吸附量介于2571mg.kg^-14930mg.kg^-1之间，邻苯二酚的最大吸附量介于3198mg.kg^-16211mg.kg^-1之间，土壤对邻苯二酚的吸附容量明显高于对苯酚的吸附容量。最大吸附量随着土壤碳酸钙含量的增加而减小。被土壤吸附苯酚的解吸率变化在12%¹8%，被土壤吸附邻苯二酚的解吸率变化在16%²0%，解吸率很低，解吸率随着土壤碳酸钙含量的增加而增加。（6）不同碳酸钙含量石灰性土壤对金霉素的吸附容量不同，最大吸附量可以达到7253mg.kg^-113517mg.kg^-1。吸附量随碳酸钙含量的增加而逐渐减少。石灰性土壤对被吸附金霉素有较高的吸附强度，被土壤吸附金霉素的解吸率在4.89%⁷.52%之间，仍有绝大多数金霉素被吸附于土壤当中。土壤中碳酸钙含量越高，被吸附的金霉素解吸率越大。（7）石灰性土壤对水溶性有机物具有较大的吸附能力，吸附率可以达到12.19%-40.54%。吸附率随碳酸钙含量的增加而逐渐减少。被土壤吸附的水溶性有机物解吸率为22.40%³0.66%。碳酸钙含量越高，土壤吸附水溶性有机物的强度越小，解吸率越大。（8）不同碳酸钙含量石灰性土壤对重金属的吸附量与对有机物的吸附量不同，土壤对重金属的吸附容量随碳酸钙含量的增加而增加，对有机物的吸附容量随碳酸钙含量的增加而减小。石灰性土壤对不同重金属及不同有机物的吸附容量及吸附强度均不同，实际中应根据碳酸钙含量及污染物种类科学确定石灰性土壤的环境容量。更多还原

【Abstract】 Large area of calcareous soils distribution in the the northern China, and most areagricultural soils. The different number calcareous materials of calcium carbonate orhydrogen carbonate calcium carbonate in soil profile,on the one hand, can control thetransformation and existence form of plant nutrients in soils, on the other hand caneffect the chemical behaviror and bioactivity of various exogenous pollutants into thesoils. This study used calcareous soils with different content calcium carbonate asmaterials, and key research the effect of calcium carbonate in soil on adsorptioncapacity and adsorption characteristic of exogenous heavy metals and some organicpollutants which on the basis of analyzing the basic properties of selected materials. Theaim is to clear the environmental effects of calcium carbonate in soils and to furtherjudge the environmental capacity and bearing ability on exogenous pollutants ofcalcareous soils with different calcium carbonate. The study results show that:（1）The pH was7.78⁸.18, the content of calcium carbonate is30.51g.kg^-1100.23g.kg^-1, and the content of organic matter and clay is no significant difference ofnatural calcareous soils. The pH of cultivated soils is7.02⁸.42, the content of calciumcarbonate is8.61g.kg^-1227.94g.kg^-1, the content of organic matter and clay reducewith the increase of calcium carbonate content. The effect of calcium carbonate ondifferent enzyme is different. Low calcium carbonate （the test for less than3%） canpromote the activity of alkaline phosphatase, while high calcium carbonate （the test formore than3%） inhibite the acitivty of alkaline phosphatase; low calcium carbonate（the test for less than5%） can promote the activity of urease, while high calciumcarbonate can inhibite the activity of intertase.（2）Soil pH and calcium carbonate content are very significant nonlinear related.The pH increase with calcium carbonate on the low level (89.91g.kg^-1), but the pHincrease slowly by and by with the further increase of calcium carbonate, until it reachbalance.（3）Calcareous soils have high adsorption capacity on exxpgenous heavy metalPb and Cu. The biggest adsorption capacity on Pb is11234mg.kg^-117513mg.kg^-1, andthe biggest adsorption capacity on Cu is9856mg.kg^-113039mk.kg^-1. The biggestadsorption capacity of Pb and Cu increase with the increase of calcium carbonate. The adsorption strength of calcareous soil on Pb and Cu is very strong. The rate ofdesorption of Pb adsorpted on soils is only less than2%, the rate of desorption of Cu isless than10%, and the more of the calcium carbonate is soils, the smaller of desorptionrate of heavy metal. This show that calcium carbonate is great significance about fixedand retention exogenous heavy metals in soils.（4）The content and proportion of each Pb and Cu form is are change afterexogenous heavy metals entered calcareous soils. Exchangeable form and residue formsdecreased, while the carbonate-bound form，Fe-Mn oxides bound form and organicform all increase to different extend, and the exchangeable form and organic form havethe trend that turn to carbonate-bound form and Fe-Mn oxides bound form. This is theimportant reasons that the adsorption capacity of calcareous soil on heavy metalincrease with calcium carbonate content.（5）The biggest adsorption capacity of calcareous soil with different calciumcarbonate on phenol is2571mg.kg^-1-4930mg.kg^-1, and the biggest adsorption capacityon catechol is3198mg.kg^-16211mg.kg^-1, and higer than phenol biggest adsorptioncapacity. The biggest adsorption capacity decreases with the in crease of calciumcarbonate content. The desorption rate of phenol adsorpted on soils is12%¹8%, thedesorption rate of catechol adsorpted on soils is16%²0%. The desorption rate is verylow and increases with the increase of calcium carbonate.（6）The adsorption of calcareous soil with different content calcium carbonate onchlortetracycline is different. The biggest adsorption capacity on chlortetracycline is7253mg.kg^-113517mg.kg^-1, and decreases with the in crease of calcium carbonatecontent. Calcareous soil has higher adsorption capacity and adsorption strenghth onchlortetracycline. The desorption rate of chlortetracycline adsorpted on soils is4.89%⁷.52%, and there are still most chlortetracycline adsorpted on soil. The higer ofthe calcium carbonate content is soils, the more of the desorption rate.（7）Calcareous soils has higer adsorption capacity on DOM.Adsorption rare is to12.19%⁴0.54%, and decreases with the in crease of calcium carbonate content. Thedesorption rate of DOM adsorpted on soil is to22.40%³0.66%. The more of calciumcarbonate content, the smaller of the adsorption stenghth on DOM, and the bigger ofdesorption rate.（8） The adsorption capacity of calcareous soil with different calcium carbonate on heavy metal and organic matters is different. The adsorption capacity of soil onheavy metal increases with the increase of calcium carbonate while the adsorptioncapacity on organic pollutant decreases with the increase of calcium carbonate. Theadsorption capacity and stenghth of calcareous soil on different heavy metal anddifferent organic matters is different. In practice, should based on calcium carbonatecontent and the varety of pollutants to sure the environmental capacity of calcareoussoils.更多还原