【作者】 张涪平；

【导师】 曹凑贵；

【作者基本信息】 华中农业大学 ， 生态学， 2012， 博士

【摘要】 矿山作为能源与原料基地,对于能源生产起着关键性的作用。但在实际生产过程中,由于矿产资源的分布具有较强的地域性,而且很多矿产资源埋藏于较深的地底,对其进行开采必然会造成生态环境的破坏或土地占用,加之开采过程中会排放各种带有毒性的矿物废弃物,会逐步形成废弃地,成为持续污染源。而作为人类赖以生存的基础,土地是必不可少的自然资源之一,大量的废弃地污染不仅对土地资源造成严重破坏,而且极大的影响了矿山的地质环境,最终导致资源的损毁,地质灾害频发,对人类的生产生活和自然环境造成不可弥补的损失。在本文笔者以恢复生态学的相关理论作为研究思想,以自然恢复为主,以人工恢复为原则,对我国西藏中部地区的拉屋铜矿区的土壤状况、生物量、生物多样性、物种情况以及矿区生产力等方面进行了深入探讨,经过综合研究,得出如下结论：(1)拉屋矿区废弃地的基质主要以砾石和块石为主,占79.8～91.8%；砂粒以下细粒含量很少,占8.2～20.2%,因此,矿区废弃地通气透水,不易保水,土温变化大,吸附有效养分能力差,保肥力差,是造成植物定居困难的重要因素之一。在矿山生态恢复过程中,应十分注重对土壤物理性质的改良。(2)矿山不同土壤类型基质养分特征分析表明,矿区样地基质pH值变化范围在6.03～7.33,有机质含量在1.2-4.1%,土壤全N在0.04-6.81g/kg,全P含量在0.65～6.81g/kg；重金属Cu的含量为原土壤的3.45-38.00倍,Zn的含量为原土地的12.05-24.49倍,Pb和Cd分别为2.57-19.46与2.45-45.86倍；有效含量分别是5.66-36.73、18.46-30.05、13.48-44.98和2.06-12.24倍,与全国土壤重金属元素平均值相比较都明显偏高。说明矿山在开采破坏之后,因雨水冲刷,矿质营养低。尽管矿区土壤速效K含量丰富,但有机质和速效P、N严重缺乏。总体矿山废弃地肥力水平差,保肥、保水能力低且受Cd、Cu、Zn重度复合污染。因此,对植被的生长极为不利。在对土地利用进行修复的过程中,应该对有机质和其他养分的修复进行充分考虑,以改善土壤结构,从根本上提高土壤的自我协调能力。(3)在拉屋矿区范围内的土壤均受到Zn、Cu、Cd、Pb等重金属不同程度的污染,从中心范围200米以外逐渐减弱；相对于对照土壤而言,原土壤的微生物量、酶活性等指标都受到很大的抑制,土壤的qC02和基础呼吸受到很大刺激,通过多元回归分析得出,在各种重金属的复合污染之下,突然的微生物活性受到极大的影响。通过这种微生物活性的指标分析能够有效的揭示出矿区土壤的重金属符合污染实际情况,可以将其作为对拉屋矿区土壤质量评价和分类的重要依据。通过主成分分析与线性相关分析表明,重金属含量与微生物群落数量与活性呈显著线性相关,其中重金属参数的主成分(H-PC)与土壤微生物参数第一主成分(M-PC1)具有最强的相关性,表明了土壤微生物参数第一主成分(M-PC1)能有效的反映藏中矿区重金属污染的情况。(4)土壤重金属含量与细菌、放线菌数量呈一定负相关关系,说明矿区重金属污染明显降低了土壤微生物区系大小。研究还表明细菌、放线菌及真菌数量的变异系数(CV%)分别为1.56、1.97、0.29,说明三大微生物对重金属胁迫的敏感性不一样,即放线菌>细菌>真菌。矿区不同污染程度土壤的细菌、放线菌有明显差异,土壤重金属污染降低了土壤微生物细菌、放线菌、氨化细菌、硝化细菌与纤维分解菌的数量和微生物量C含量,提高了基础呼吸与qC02。(5)拉屋矿区的原生态草地植物的多样性和丰富度指数会在一定范围之内随海拔变化而变化,当海拔4660m时达最高,后逐渐降低。7、8月份丰富度、多样性指数高,6月、9月丰富度及多样性指数低。表现出在不同的海拔范围内,处于同一生长期的原生态草地植物物种分布和组成存在一定差异,即使在同一海拔高度,物种由于季节的不同也会表现出不同的生长变化。此外,通过研究得知,在植被的不同物种中对于资源的竞争主要为水和光热资源,次之是土壤养分、颗粒和地貌等。水分和温度是影响植物生态位变化的主要因素。在不同的群落中,物种之间的竞争关系也存在着较大差异,即使是同一种植物,有时也会形成不同的竞争关系。这种差异性主要是由较为稳定的地貌、土壤条件、气温、生态位以及逐年变动的降水情况共同造成的。所以,在选择矿山生态恢复物种的过程中,应该按照原生态草地草本植物的季节分布特征、种群生态位特征以及海拔分布特征,对物种组合进行不同的选择,从而实现多样化的矿山生态恢复,促进矿山植被的蓄水功能、保土功能及保持养分的功能,以此构建一个具有多样化稳定而高效的群落,从而促进生态系统恢复的良性化和稳定性。(6)土壤有机质的含量对植物生产力影响十分显著。试验研究发现,通过有机土的混合能够极大的提升垂穗披碱草种子的发芽速度,提高发芽几率,当表层土壤有机土含量达到一半时,其发芽率已趋近最高；在高原环境条件下,垂穗披碱草生物量的形成与气温、降水季节的变化有着明显的关系和地域特色。其产量高峰期一般是出现在8月上旬。在此之前的增长模式符合于Logistic生长方程。因此,在矿山实际恢复过程中,除增施有机肥外,充分利用矿山水热关系,提高优势物种生产力,促进优势物种对矿山生态恢复的作用。(7)通过对试验结果的分析可以得出：对高原矿山采取生态恢复策略,应该充分结合生物和工程措施进行,在选择生物恢复物种措施时,应该充分重视物种的季节特征、生态位分布特征以及矿区的自然条件,选择生长速度较快、根系较为发达、耐旱、耐高温的优势物种作为矿山生态恢复的首选。并采取施肥、客土等一系列辅助手段,加快矿山生态恢复的速度。(8)通过对矿山气象因子、不同样段土壤(基质)理化性质、成熟种植技术、矿山种植技术实验、植物生长限制因子等方面的分析和研究。得出道路建设破坏面技术恢复、矿渣堆积滑坡体恢复、道路建设形成的滑坡体恢复和尾矿库恢复等4项种植技术模式以及披碱草、老芒麦,辅助植物介菜型油菜混播(50：35：15),创建适宜植物定植的水、温等表面微环境；先锋植物在分蘖形成、分蘖完成时叶面施肥(水、N),积累先锋植物碳水化合物和糖分,增强先锋植物安全越冬能力；95：5种子与保水剂颗粒混合播种,覆地膜,再覆遮阴网,保湿、增温,促进先锋植物种子发芽、幼苗快速生长,建立定植群落等关键技术和相似生态环境矿山的生态恢复技术体系。总体来看,矿山生态恢复并不只是追求快速恢复矿山生态环境,而是应该从整体出发,以矿山生态系统的稳定、生物多样化以及矿山生态恢复的各种效益为目标,对矿山整体生态系统进行综合考虑的建设工程。更多还原

【Abstract】 Mine as a base for energy and raw materials for energy production plays a critical role. But in the actual production process, the distribution of mineral resources has a strong regional, and many mineral resources buried deeper underground, its exploitation will inevitably cause damage to the ecology or land occupied, coupled with the mining process emissions from a variety of minerals with toxic waste will gradually form a wasteland, a continuing source of pollution. As the basis for human survival, the land is one of the essential natural resources, a large number of abandoned land pollution not only cause serious damage to land resources, but also a great impact on the mine geological environment, and ultimately lead to resource damage, geological disasters, causing irreparable damage on the production of human life and the natural environment. In this article the author in order to restore the ecology theory as a research idea to the natural recovery mainly to artificially restore the principle of soil conditions on the copper area of the house pull of China’s central Tibet, biomass, biodiversity, species as well as The mining area productivity, such as in-depth, comprehensive study, the following conclusions:(1) pull the house mining wasteland matrix mainly of gravel and stone, accounting for79.8to91.8%; sand the following fines content rarely, accounting for8.2to20.2%, therefore, abandoned mining area ventilation permeable and difficult water soil temperature changes, the adsorption of available nutrient poor, ensure fertility, is one of the important factors to cause the plants to settle difficulties. Mine ecological restoration process should be paid great attention to the improvement of soil physical properties.(2) mining of different soil types Nutrient characteristics analysis showed that the mining area sample matrix pH value range of6.03to7.331.2to4.1%organic matter content, soil total N in0.04～6.81g/kg, total P content of0.65～6.81g/kg;3.45-38.00times the original soil content of Cu, Zn12.05-24.49times the original land, Pb and Cd were2.57-19.46and2.45-45.86times; effective content is5.6636.73,18.46to30.05,13.48to44.98and2.06to12.24times, compared with the national heavy metal elements, the average is significantly higher. Mines in mining after the destruction of rainwater falls on mineral nutrition. Mine soil available K, organic matter and available P, N, is a serious lack. Fertility level of the overall mining wasteland, and fertilizer, low water retention capacity and subject of Cd, Cu and Zn in severe compound pollution. Therefore, the growth of vegetation is extremely unfavorable. Repair of organic matter and other nutrients in the repair process of land use, it should be fully taken into account in order to improve the soil structure, and fundamentally improve the soil self-coordination.(3) pull the housing within the mining area of the soil are subject to the Zn, Cu, Cd, Pb and other heavy metals polluted to varying degrees, gradually weakened from the center area200meters away; relative to the control soil, the original soil microbial biomass, enzyme activity were greatly inhibited the soil qCO2and basal respiration were under great stimulus, obtained by multiple regression analysis, under the combined pollution of heavy-metal, the sudden microbial activity to be greatly affected. Index analysis of the microbial activity can reveal the mine soil heavy metals in the actual situation of the pollution, can be used as an important basis on mine soil quality assessment and classification of pull housing. By principal component analysis and linear correlation analysis showed that the heavy metal content and the quantity and activity of microbial communities was a significant correlation, the principal component of the parameters of heavy metal (H-to-PC) and soil microbial parameters, principal component (M-PC1) has The strongest correlation, indicating that the first principal component of the soil microbial parameters (M-PC1) can effectively reflect the situation of Tibet in the mining area of heavy metal pollution.(4) soil heavy metals and bacteria, actinomycetes showed some negative correlation between the description of Heavy Metal pollution significantly reduced the size of the microbial flora. The study also showed that bacteria, actinomycetes and fungi, the number of the coefficient of variation (CV%) were1.56,1.97,0.29, three micro-organisms to heavy metal stress sensitivity is not the same, namely actinomycetes> bacteria> fungi. Mining areas of different degree of pollution of soil bacteria, actinomycetes, soil heavy metal contamination of soil microbial bacteria, actinomycetes bacteria, ammonification bacteria, nitrifying bacteria and fiber decomposition of the number of bacteria and microbial biomass C content, basal respiration The and qCO2.(5) pull the housing mine the original ecology of grassland plant diversity and richness indices will be within a certain range with elevation changes and changes in the highest when the altitude of4660m, and then decreases. July and August, richness, diversity index, June, September richness and diversity indices. Showing the distribution of the original ecology of grassland plant species in different altitude ranges in the same growing season and to form there are some differences, even in the same altitude, the species due to the different seasons also showed different growth and change. In addition, the study indicated that the competition for resources in the different species of vegetation for water and light and heat, followed by soil nutrients, particles, and landscapes. Moisture and temperature are the main factors affecting changes in plant niche. The competition between the species in different communities, there are also a big difference, even if it is the same kind of plants sometimes form different competitive relationship. This difference is more stable landscape, soil conditions, temperature, niche, and yearly changes in precipitation in common cause. Therefore, in the process of mine ecological restoration species, it should be distributed according to the season of the original ecology of grassland herbs characteristics, population niche characteristics and altitude distribution characteristics of species combinations of different options, in order to achieve a variety of mines ecological restoration, promote the natural reservoir of the mining vegetation, and soil conservation function and maintain nutrients, in order to build a diversified stable and efficient community, thereby contributing to the benign and stability of ecosystem restoration.(6) soil organic matter content is very significant impact on plant productivity. The pilot study found that, through a mixture of organic soil can greatly enhance the Elymus nutans grass seed germination speed and improve germination probability of topsoil organic soil content reaches half its germination rate approaching the maximum; environmental conditions in the highlands, the nutans Elymus biomass formation and the temperature and precipitation in the seasonal changes have a clear relationship and geographical characteristics. Its peak production period is usually in early August. Prior to this pattern of growth in line with the logistic growth equation. Mine the actual recovery process, in addition to organic manure, make full use of mine water heat relations, improve the productivity of the dominant species, and promote the role of the dominant species on the mine ecological recovery.(7) can be obtained through the analysis of test results:mining on the plateau to take ecological restoration strategy should be fully integrated with the biological and engineering measures, select the biological recovery of species measures, we should pay full attention to the seasonal characteristics of the species, niche distribution characteristics natural conditions of the mining area, select grew faster, more developed root system, drought, cold resistant, the dominant species of choice for ecological restoration as mine. And take a series of supplementary means of fertilization, and new soil, to accelerate the speed of the mines ecological restoration.Overall, the mine ecological recovery is not just the pursuit of the fast recovery of ecological environment in mining, but should be starting from the overall, to mine the stability of ecosystems, biodiversity and ecological restoration of mine the benefits of goal of mine as a whole ecosystem considering the construction project.(8) From analysising and researching meteorological factor of mine, physical and chemical properties of different sectional soil(stromal), mature planting technology, the test of planting technology in the mine, and the limiting factor of plants growing, we can get the following achievements:about4modes of seeding technology, including thetechnological restoration of the failure surface of road construction, the restoration of landslide of slag accumulation, the restoration of the landslide which road constuction formed, and the restoration of the tailings, and the mixed seeding(50:35:15) of the Elymus, the Sibiricus, the Brassica juncea which is auxiliary plant,which can create the appropriate surfacial microenvironment of water and temperature of plant colonization. Forever, fertilizing the foliar of pioneer plant can accumulate carbohydrates and sugars and strengthen its overwintering ability safely. In addition, the mixed seeding(95:5) of seed and grain of aquasorb,the recvering of film and shade network, the moisture and the warming can promote seed germination and rapid growth of seedling, as well as establish the crucial technology and thetechnology system of ecological restoration of similar ecological envirnment in mining.更多还原