【作者】 申俊峰；

【导师】 孙岱生； 李胜荣；

【作者基本信息】 中国地质大学（北京） ， 矿物、岩石、矿床， 2003， 博士

【摘要】 鉴于废弃物堆积引起的环境恶化和水土流失导致土地沙漠化及生态退化，利用废弃物改良土壤，修复生态环境的研究工作便具有多重重要意义。本文利用包头地区粉煤灰、水库淤泥和污水沉淀物(也称“三废”，下同)，对包头北梁地区贫瘠砂质土壤进行了改良实验研究，取得非常明显的效果。 本文主要的研究工作及所取得的成果如下。 一．调查研究： 在总结前人资料的基础上，对我国尤其是包头地区“三废”堆积情况及面临的环境问题，以及我国土地沙漠化、水土流失的严重情况进行了阐述，重点论述了包头地区土地沙漠化程度及土壤概况。 在研究国内外资料170篇的基础上，重点阅读144篇，并通过查新较详细论述了本课题的研究现状及存在问题。 1．水库淤积物：前人曾对水库淤积物的化学组成、重金属和放射性元素的地球化学行为，及土壤改良方面进行过少量研究。但就水库淤积物的矿物组成、全面系统的物理性质，特别是农业化学成分特点尚缺乏研究。利用水库淤积物进行植被恢复和生态建设的研究未见公开报道。 2．粉煤灰：曾有大量文献报道过粉煤灰在建筑材料、水泥及混凝土添加剂、铺路等方面的应用。其中有部分文献论述了粉煤灰化学组成、矿物组成、物性及在农、林业方面的应用。但未见有关粉煤灰全面系统的物性研究，特别是农化分析资料。另外，传统的观点认为；粉煤灰可以对粘质土壤予以有效改良，对砂质土壤没有效果。因而尚未见利用粉煤灰进行砂地改良植树种草的报道。 3．污水沉淀物：污水沉淀物用作农肥民间早有应用，但缺乏科学系统的研究。特别缺乏有关农业化学分析、物理性质及矿物组合的研究。尤其未见利用污水沉淀物作为树肥改良砂质土壤植树种草的报道。 总之，利用“三废”中单一废弃物作为肥料改良土壤有过报道，但“多种废弃物联合改良土壤”在国内、外均少有报道。 二．包头试验区土壤的研究 研究认为，包头北梁区土壤贫瘠，植物生长所必须的养分如有机质和氮、磷，钾含量均较低。如有机质多在1％以下，仅个别地方表土层可达1—2％，尚属有机质缺乏土壤；全氮含量一般小于0.07％，最高达0.144％，可见土壤中氮含量偏低；全磷含量仅为0.01—0.06％，最高也不足0.1％，说明该区土壤严重缺磷；全钾含量一般也低于1.7％。其它有益微量元素如Fe、Mn、Zn、B、S、Cl等含量也较低，一些有益微量元素的含量甚至低于植物生长的最低要求，如有效Mn仅为1—3ppm、有效Cu不足1ppm、有效B为0.1—0.3ppm、有效Mo小于0.1ppm等。 此外，该区土壤粒度较粗，粘粒含量少。粒度分析表明：该土壤粒级主要分布在0.001—2mm范围，其中0.1—1mm的粒级占80％以上。小于0.005mm粒级约7％，小于0.002mm粒级不足3％，属近紧砂土的砂壤土。土壤的吸水率仅24ml／100g，说明土壤保水性较差，且容易漏肥漏水。土壤导热率为0.202w／m·k，可见保温性也较差。总之，该区土壤是养分缺乏，物理性状较差的土壤。 土壤矿物组合以石英和长石为主。 该区土壤质地属近紧砂土的砂壤土。根据矿物组成、养分特征及成因等综合考虑，本试验区土壤分类属于：钙层土纲，栗钙土类，淡栗钙土亚类。 三．包头地区“三废”的分析研究 1．“三废”的粒度及物性特点： 通过对“三废”粒度和物性（容重、比重、空隙度、吸水率、导热率、饱和导水率等）的系统研究，获得一系列重要信息。 1．1粉煤灰：其粒度相当于砂壤土。高孔隙率、良好的畜水性（蓄水率高达77ml／1009）和低导热率使得其具有很好的保水性和保温性，高的孔隙率和好的蓄水性有利于微生物的生存和繁殖。。，“ 1．2污水沉淀物：其粒度相当于重壤上，含有大量的粘粒和胶粒及有机质o具较高的孔隙率、好的蓄水性和较低的导热率。对土壤的细化和团聚化起重要作用，同时可以引人大量的微生物。 1．3水库淤积物：其粒度和物性相当于轻壤土。 总上，“三废”联合用于改良土壤，可以取长补短，有效地改良土壤质地，使砂质土壤细粒化、团聚化，使砂士向壤土转化。并改善土壤的保水性、保温性等物理性质。 2．“三废”矿物组合： 粉煤灰中存在着大量玻璃体，晶质相矿物主要有莫来石、石英、铁的氧化物及少量方解石、石盐等。透射电镜研究表明：玻璃体中含有大量P、S等有益微量元素。 水库淤积物的矿物组合与土壤类似，即矿物主要以石英和长石为主，少量其它暗色硅酸盐矿物。另含有一些粘土矿物，如蜂石一绿泥石混层矿物，高岭土，伊利石，蒙脱石等。粘土矿物半定量分析结果表明：留宝窑水库淤积物中，离子交换能力较强的蒙脱石含量高于试验区土壤 11％。 污水沉淀物的矿物组合以粘土矿物为主，并含有石英、长石和少量碳酸盐、石膏编。 3．“三废”的养分元素含量：。 3．l粉煤灰中含有多种植物生长所需的营养元素，如P、K、Fe、Cu、Zn、o、B、S等。其中有效磷高出土壤10．56－30．15倍等，有效硫高出土壤23—35倍等。此外，污水沉淀物与粉煤灰的强烈作用，还可加速粉煤灰中一些养分元素的释放。更多还原

【Abstract】 The researches on soil improvement and environment renovation by utilizing solid wastes as soil additives, are very important, because both environmental and entiroment degeneration. Solid wastes accumulation and soil erosion have led to serious. So the soil improvement trial by adding coal ash, reservoir sediments and sewage sludge (so called ’three kinds of wastes’) for lean soil in Beiliang area, Baotou city, were carried out. And the great achievement of the research work was gotten.The soil is arid in Beiliang area, Baotou city. Some nutrients such as organic material, nitrogen, phosphorus and Fe, Mn, Zn, B, S, Cl and so on is lower in the soil than the requirement for plant growth,. The granularity of the soil is coarse, and only few conglutination grains exist in the soil. The soil is poor at water holding and fertilizer-holding. The soil in Beiliang district, therefore, is not only poor in nutrients but also bad in physical properties.The components of the ’three kinds of wastes’ collected from Baotou was analyzed, and the results showed that: (1) there are many kinds of nutrients for plant growth in the coal ash. For example, available phosphorus in coal ash is 10.56 - 30.15 times to that in the soil. Dissolving experiments also showed that some of the nutrient elements in coal ash can be released quickly under the strong effect by sewage sludge, (2) The reservoir sediments inherited more nutrients from the soil of upper drainage area, and the contents of the nutrient elements are gradually accumulated in the reservoir. For example, the contents of available nitrogen and organic material in reservoir sediments are respectively 2.6 - 8.85 times and 1.98 - 4.73 times higher to those of the soil from the upper drainage area. (3) There are abundant available nitrogen, phosphorus, potassium, organic material and trace elements in sewage sludge. Some of them are several times to hundreds times higher in content than that of the soil. In addition, sewage sludge generally contains a lot of microbes, which can promote the transformation of nutrients. So the ’ three kinds of wastes’ mentioned above are able to supply effectively nutrients for soil.In the ’three kinds of wastes’, the contents of the harmful elements such as Cd, Cr, Cu, Pb, Zn, Hg, As are lower than the Chinese national standards for agricultural soil. It means that the ’wastes’ can be safely used for planting of trees and grasses.Compared with the soil, the granularities of the coal ash and sewage sludge are fine, their densities are low, and the porosity, sop rates and saturated water transmission rates are higher, but their thermal conductivity is lower. The granularity of the reservoir sediments is finer than that of the soil too, and their density is similar with each other, but the porosity and water storage ability of the reservoir sediments are slightly higher than those of the soil. And compared with the soil, thermal conductivity of the reservoir sediments is lower. So the physical properties of the soil can be improved effectively by adding the coal ash and reservoir sediments.Planting trials were carried out with soils mixed with certain proportions of the ’three kinds of wastes’. The results showed: (1) the heights and the haulm diameters of the maize growed on the mixed soils were better than those of the maize growed on the lean soil. And the productivities of the maize on the mixed soils were 1.89 - 2.62 times to those of the maize on the lean soil; (2) The heights and branch numbers of the thorn trees on the mixed soil were better than those on the lean soil; (3) lawn grass planting on the mixed soil were very flourish, but there were few lawn grasses up on the lean soil.Regarding the mechanism that the plant can be promoted by adding the wastes into the soil, following viewpoints can be given in mineralogy, geochemistry and biochemistry. (1) There are much more fine grains in the ’three kinds of wastes’. Being added with the ’wastes’, the soil will greatly increase its rates of the fine grains and conglutination更多还原