自然演替过程中铜尾矿土壤酶活性的变化

铜陵矿区堆放了大量不同时期的铜尾矿,形成大量铜尾矿废弃地,其中的大部分铜尾矿废弃地处于自然生态恢复状态。并形成典型的原生演替系列。为探讨废弃地自然生态恢复中不同演替阶段植物群落变化与土壤酶活性变化的关系,对铜陵3处不同时期弃置的尾矿废弃地进行了调查。随着自然生态系统演替的进行,尾矿中土壤酶活性逐步提高,维管植物群落下尾矿中土壤酶活性〉隐花植物结皮下尾矿中土壤酶活性〉裸地处土壤酶活性;位于植物群落下的尾矿废弃地中脲酶、碱性磷酸酶、过氧化氢酶的活性从表层至下层逐渐降低。不同植物群落对尾矿中土壤酶活性影响有很大差异,位于木贼群落下的尾矿中几种土壤酶的活性高于位于白茅群落和中华结缕草群落下的尾矿中酶的活性。相关分析表明,土壤酶活性与有机质、总N表现出显著的正相关。     

铜尾矿废弃地土壤动物多样性特征

土壤动物的恢复、群落演替及其多样性对于铜尾矿废弃地的生态重建具有重要意义.为了解铜尾矿废弃地土壤动物群落多样性特征,在铜陵市铜尾矿区设置4个样地23采样点,共捕获土壤动物4622只个体,隶属5门10纲18目29类.结果表明,铜尾矿自然废弃地与其对照组土壤动物多样性差异明显,自然废弃地土壤动物丰富度指数d、大型土壤动物密度、中小型土壤动物密度、多样性指数H'和D·G指数均小于其对照组且存在显著差异.而复垦废弃地中小型土壤动物密度和D·G指数小于其对照组且存在显著差异,多样性指数H'大于其对照组且差异极显著,其他土壤动物群落指标与其对照组均无显著差异.相似系数q表明,外围林地间土壤动物群落相似性最大,其次是复垦废弃地与外围林地间,自然废弃地与其它3个样地间相似性最小.从垂直分层来看,复垦废弃地土壤动物表聚性强于自然废弃地,尾矿废弃地表聚性强于外围林地.灰色关联分析表明,铜尾矿区土壤理化性质与土壤动物群落结构指标关系密切,其中最重要的因素是土壤含水量和总钾含量,重金属全镉含量也不容忽视,植被因素和土壤全铜含量对土壤动物的影响相对较小.由此可见,土壤含水量、土壤基质的优劣、土壤有机质与营养元素的含量等因素限制了铜尾矿废弃地土壤动物的恢复与重建,而这些因素的改善主要归功于尾矿废弃地的土地复垦和作物种植.所以,尾矿废弃地的复垦与利用有利于土壤动物的恢复与重建.     

红壤矿区复垦土壤的微生物生态特征及其稳定性恢复研究Ⅱ.对土壤微生物生态特征和群落结构的影响

研究了浙江哩铺铜矿废弃地土壤微生物生态特征和群落结构.结果表明,与对照土壤相比矿区土壤微生物生态特征发生了明显的改变,微生物呼吸速率减弱,微生物生物量显著降低,微生物生理生态参数C_mic/C_org下降、qCO₂值明显升高,重金属对土壤微生物生态特征有明显的影响.Biolog结果显示,矿区土壤微生物的群落结构发生变异,对能源碳的消耗量和速度明显升高,改变了微生物利用碳源的种类,使微生物消耗更多的能源,以维持其正常的生命活动,利用效率降低,明显不如对照土壤.由此可见,微生物生态特征是表征矿区复垦土壤重金属污染的灵敏、有效和可靠的生物学指标.     

松嫩草原不同演替阶段大型土壤动物功能类群特征

大型土壤动物处于整个土壤食物网的最顶端,其各功能类群控制着其他动物所需资源的有效性,是土壤生态系统的重要组成部分。为了查明松嫩草原大型土壤动物的功能类群特征,在2006年5—10月期间,逐月对松嫩草原羊草、羊草+虎尾草、虎尾草、碱茅、碱蓬和光碱斑6个演替阶段大型土壤动物的功能类群组成、结构、多样性等特征进行研究。依据其食性将该区土壤动物划分为杂食性、植食性、捕食性和腐食性4个功能类群其中,杂食性土壤动物个体密度所占比例最多为39.16%,植食性土壤动物的类群数所占比例最多为50.00%,腐食性土壤动物个体密度和类群数所占比例均最小,分别为8.09%和12.82%。各功能类群土壤动物个体密度和类群数的相关性不显著(P0.05)。从水平结构来看,总体上各功能类群土壤动物在羊草群落和羊草+虎尾草群落个体密度和类群数较多,在无植被的光碱斑生境土壤动物的个体密度和类群数较少,植食性土壤动物的个体密度和类群数、杂食性土壤动物个体密度、腐食性土壤动物个体密度和类群数随着群落演替发生显著的变化(P0.01)。植食性和腐食性土壤动物个体密度和类群数相关性显著(P0.05)。垂直结构上,0—10 cm土层和20—30 cm土层除捕食性土壤动物个体密度以外,其它各功能类群土壤动物个体密度随着群落演替发生显著的变化(P0.05或P0.01);10—20 cm土层,除腐食性土壤动物个体密度以外,其它各功能类群土壤动物个体密度随着群落演替发生显著的变化(P0.05或P0.01)。0—10cm土层,植食性和杂食性土壤动物个体密度(P0.05)相关性显著;10—20 cm土层,植食性和腐食性土壤动物个体密度(P0.05)相关性显著。不同演替阶段对各功能类群土壤动物的多样性影响程度有所不同。4种功能类群土壤动物在羊草群落和光碱斑之间相似性指数较低,个体数量组成在演替初期的羊草群落和演替后期的光碱斑差异比较大。以上研究结果表明,松嫩草原不同退化演替阶段能够降低大型土壤动物功能类群组成和结构复杂性。     

大兴安岭落叶松林不同演替阶段土壤细菌群落结构与功能潜势

采用土壤细菌16S rDNA高通量测序方法研究了大兴安岭汗马自然保护区落叶松林不同演替阶段的土壤细菌群落结构和功能.结果表明: 不同演替阶段落叶松林土壤细菌优势门为变形菌门、酸杆菌门、疣微菌门、拟杆菌门、放线菌门、浮霉菌门和绿弯菌门,随着演替的进行,酸杆菌门相对丰度逐渐增加,绿弯菌门相对丰度逐渐减少,优势门相对丰度在不同演替阶段不同.细菌群落α多样性在不同演替阶段间无显著差异,但其群落结构分别在落叶松幼龄林与中龄林、幼龄林与过熟林、近熟林与成熟林之间存在显著差异.土壤氧化还原电位、土壤pH和有效磷是影响细菌群落结构的主要环境因素,其中土壤氧化还原电位对微生物群落结构影响最大.随着演替的进行,细菌参与的固氮作用、反硝化作用、氨氧化作用、木质素降解作用呈逐渐减弱的趋势,硫酸盐异化还原作用呈先降后升的趋势,碳固定作用呈先升后降的趋势,碱性磷酸酶没有明显的变化规律,影响土壤功能的主要因素有土壤有效磷和氧化还原电位等.     

土壤动物群落研究进展

许多研究表明:土壤动物群落与土壤环境有密切关系,土壤动物的群落结构、功能在土壤生态系统中有不可替代的重要作用,是系统正常运行的关键环节,土壤动物逐渐成为生态学和土壤学领域研究的热点之一。本文介绍了我国土壤动物区系研究进展,从群落结构、群落功能和群落演替三个方面分析了国内外土壤动物群落在森林和农业生态系统中最新研究现状,内容包括土壤环境评价、凋落物分解、土壤健康的指示作用、与污染环境的关系等几个方面,最后从全球环境变化、土壤生态系统过程和土壤生物多样性保护等三个重要领域提出土壤动物群落研究展望和建议。     

淮南煤矿废弃地重金属污染对土壤动物群落的影响

土壤动物是煤矿废弃地生态环境变化最敏感的指示指标,已成为土壤生态恢复研究的热点。通过对淮南大通废弃地土壤重金属含量分析和污染等级确定,选取2条不同污染带的8个采样点调查,分析重金属污染对土壤动物的影响,结果显示:(1)大通煤矿废弃地8个样地,共获得土壤动物2286个,隶属于4门8纲24个类群,优势类群为弹尾目、线虫类和蜱螨目,膜翅目、蜘蛛目等9类为常见类群,其余12类为稀有类群。(2)重金属污染对煤矿废弃地的土壤动物群落影响显著。煤矸石和原化工厂的重金属污染对土壤动物群落的影响表现为:随着污染程度增加,个体数和类群数均呈减小趋势,群落的均匀性、多样性和密度-类群指数也呈降低趋势,优势度指数在煤矸石堆污染带呈逐渐降低趋势,在化工厂污染带则先减小后增加。(3)重金属污染使土壤动物群落多样性降低,群落结构趋于简单,重金属污染与群落结构指数之间呈显著负相关,与土壤有机质等营养物质关系不明显。(4)随污染程度增加,土壤动物垂直分布的表聚性降低。     

红壤矿区复垦土壤的微生物生态特征及其稳定性恢复研究Ⅱ．对土壤微生物生态特征和群落结构的影响

研究了浙江哩铺铜矿废弃地土壤微生物生态特征和群落结构．结果表明,与对照土壤相比矿区土壤微生物生态特征发生了明显的改变,微生物呼吸速率减弱,微生物生物量显著降低,微生物生理生态参数Cmic／Corg下降、qCO2值明显升高,重金属对土壤微生物生态特征有明显的影响．Bio1og结果显示,矿区土壤微生物的群落结构发生变异,对能源碳的消耗量和速度明显升高,改变了微生物利用碳源的种类,使微生物消耗更多的能源,以维持其正常的生命活动,利用效率降低,明显不如对照土壤．由此可见,微生物生态特征是表征矿区复垦土壤重金属污染的灵敏、有效和可靠的生物学指标．     

樟村坪磷矿废弃地植物群落的形成与演替

通过分析湖北省宜昌县樟村坪磷矿废弃地植被的组成、空间结构、各成分综合优势比其群集度的变化以及植物分布与环境因子的相关性等问题,探讨了该地植被恢复过程中植物群落形成与演替的一般规律。结果表明,废弃地6种演替植物群落的形成是先锋植物种类入侵、定居、群聚和竞争的结果,在植物群落形成与演替的过程中,各种类成分的种群数量及综合优势比呈动态变化,废弃地植物群落形成与演替的过程按演替序列可分为3个阶段。植物群落形成与演替还与环境因子有关,废弃地高浓度的土壤效磷是影响植物生长与分布的胁迫因子。伴随着群落的形成与演替,植物群落的物种多样性呈逐渐增加的趋势。     

铜陵市狮子山铜尾矿废弃地生态恢复过程中植被演替规律

通过对铜陵市狮子山铜尾矿废弃地植被的实地调查,探讨了该废弃地的植被状况及其植被恢复过程中的植物群落形成与演替的一般规律与特征.结果表明:目前废弃地入侵、定居植物共49种,隶属于15科38属,主要包括菊科(12种)、禾本科(11种)、豆科(8种)等.极端贫瘠和过高的重金属含量(特别是Cu、Cd,平均超出对照土样的20～30倍)是限制植物在废弃地定居的主要因素.全部植物中,一、二年生草本植物26种,多年生草本植物20种.风播种子和果实是废弃地植物繁殖体的主要来源.尾矿废弃地植物群落形成具有先锋植物的入侵、定居、群聚和竞争等过程,共形成了14种相对稳定的小群落,包括单优势种群落、次优势种群落和共优势种群落三种类型.伴随着尾矿废弃地植物群落的形成与演替,群落中物种丰富度增大,多样性指数呈增加趋势,而群落内植物种综合优势比间的差值趋于减小.     

天童常绿阔叶林五个演替阶段凋落物中的土壤动物群落

为探讨森林凋落物中土壤动物群落的结构特征以及土壤动物群落随植被演替而发生的变化 ,于 2 0 0 3年冬季 ,对浙江天童常绿阔叶林 5个演替阶段凋落物中的土壤动物群落 ,按代表不同分解阶段的新鲜凋落物层、腐叶层和腐殖土层进行了调查研究。共获得土壤动物 13381只 ,分别隶属于 2门 8纲 2 0目。优势类群为蜱螨目 (Arcarina)和弹尾目 (Collem bola) ,二者共占总数的 94 .2 4 % ,A/ C为 7.6 6 ;常见类群为双翅目 (Diptera)。研究结果表明 :(1)凋落物中的土壤动物群落存在明显的有别于真土层的垂直分布 ,类群数和个体数总体表现为向下递增的趋势。共有 19类、5 9.0 3%的土壤动物分布在底部腐殖土层 ,仅 8类、5 .35 %的土壤动物分布在新鲜凋落物层 ,其余共 8类分布在中间腐叶层。而且 ,不同类群在各演替阶段的分布表现出一定的差异 ;(2 )凋落物中土壤动物群落随植物群落的演替而发生明显的变化 :个体总数和类群总数在演替顶极阶段最高 ,其次为中期阶段 ,演替初期最低。但是 ,在目这一分类等级上 ,各演替阶段凋落物中土壤动物群落的主要类群基本一致 ,均为蜱螨目、弹尾目、双翅目和鳞翅目 (L epidoptera) ;(3)相似性分析表明 ,演替中期凋落物中土壤动物群落与顶极阶段最为相似 ;但它们的Shannon- Wiener多样性     

我国土壤动物群落生态学研究综述

总结了我国土壤动物群落生态学研究的特点,即区域分布集中于中国东部、研究的生态系统类型广泛、研究角度多种多样与应用研究发展迅速。并从土壤动物群落与环境关系、土壤动物群落的组成和多样性、土壤动物群落结构、土壤动物群落功能、土壤动物群落演替与受干扰生态系统的土壤动物群落6个方面综述其最新研究成果。在此基础上指出我国土壤动物群落生态学中有待开拓的研究领域是基础研究、特色区域和生态系统的研究、土地覆盖/土地利用对土壤动物的影响研究、土壤动物多样性及其保护研究、土壤动物在土壤生态系统和陆地生态系统物质循环和能量流动中的作用研究、全球变化响应研究与土壤动物应用研究。     

Soil animal communities at five succession stages in the litter of the evergreen broad-leaved forest in Tiantong,China

Soil animals are abundant in forest litter layer,but little attention has been Paid to the vertical distribution of community structure of soil animals in the layers at different plant community succession stages.The forest litter layer can be divided into fresh litter layer(L),fermentation layer(F)and humus layer(H),which may represent different litter decomposition stages.The aim of the study is to ascertain the vertical distribution features of soil animal communities among the three litter layers and the change in the succession process of the Evergreen Broad-Leaved Forest(EBLF)in Tiantong,Zhejiang Province,China.Soil animal communities in the five plant communities at different succession stages were investigated during the 2003 winter.Soil animals,which were collected by using Tullgren funnels,amounted to a total of 13381 individuals falling into 2 phyla,8 classes and 20 orders.The dominant groups were Acarina and Collembola,accounting for 94.24% of the total individuals,with the number of Acarina individuals 7.66 times than that of Collembola.The common group was Diptera.The results indicated that there was a distinctive vertical distribution of the soil animal communities in the forest litter laver,but it differed from that in soil below the litter layer.In contrast to those in the soil,the soil animals in the litter layer generally tended to increase in both group abundance and density from the top fresh litter layer to the bottom humus layer.Altogether 19 groups and 59.03% of total individuals were found in the bottom layer,while only 8 groups and 5.35% of the total individuals in the top.Moreover,there were some variations in the distribution of the soil animals at different plant succession stages.85.19% of Homoptera and 100% of Symphyla were found in the litter layer at the climax succession stage.while 75.61% of Thysanoptera at the intermediate succession stage.Therefore,these groups might be seen as indicative groups.The total numbers of soil animal groups and individuals in the litter layers greatly changed in the succession process of the EBLF.They both were greatest at the climax,moderate at the intermediate and smallest at the primary succession stage.However,the main soil animal groups in the litter at the different succession stages were essentially the same.They were Acarina,Collembola,Diptera and Lepidoptera.Although similarity analysis revealed that the soil animal communities in the litter at the intermediate succession stage were most similar to those at the climax succession stage,they differed greatly from each other in the Shannon-Wiener diversity index.The Shannon-Wiener index was highest at the climax succession stage and lowest at the intermediate succession stage.Finally,the paper discusses the following three questions:the role of soil animals as indicators for plant community succession;the role of different soil animal groups in the litter decomposition at different stages;and the major factors affecting the composition and distribution of soil animals in the litter.This paper provides a new perspective for the research on the succession mechanism of plant communities and the decomposition functions of soil animals.     

宁夏银北盐碱地油葵田土壤动物多样性及群落结构

【目的】调查宁夏银北盐碱地油葵田的土壤动物多样性及群落结构,探讨不同改良时间盐碱地土壤动物多样性及群落结构与环境因子之间的相关性。【方法】生物与环境因子之间的关系研究一直是生态学研究的热点,尤其是恢复生态学中如何设计环境因子来恢复生物群落的结构和功能最近引起了国内外学者的关注。以宁夏银北盐碱地油葵田为对象,研究了不同改良时间盐碱地中油葵田土壤动物与环境因子的相互关系,采用野外调查和室内试验相结合。【结果】共采集12个土壤动物类群,优势类群为弹尾目(60.67%)、蜱螨亚纲(23.24%)和鞘翅目(6.45%);土壤动物物种多样性、丰富度指数和均匀度在未改良盐碱地中较高。【结论】土壤pH值、碱化度和全盐质量分数是土壤动物分布的限制因素,土壤动物的数量随土壤pH值、碱化度和全盐质量分数的降低而增加。这些结果为盐碱地改良的恢复与评价提供了重要的数据支持和基础资料。     

Soil animal communities at five succession stages in the litter of the evergreen broad-leaved forest in Tiantong, China

Soil animals are abundant in forest litter layer, but little attention has been paid to the vertical distribution of community structure of soil animals in the layers at different plant community succession stages. The forest litter layer can be divided into fresh litter layer (L), fermentation layer (F) and humus layer (H), which may represent different litter decomposition stages. The aim of the study is to ascertain the vertical distribution features of soil animal communities among the three litter layers and the change in the succession process of the Evergreen Broad-Leaved Forest (EBLF) in Tiantong, Zhejiang Province, China. Soil animal communities in the five plant communities at different succession stages were investigated during the 2003 winter. Soil animals, which were collected by using Tullgren funnels, amounted to a total of 13 381 individuals falling into 2 phyla, 8 classes and 20 orders. The dominant groups were Acarina and Collembola, accounting for 94.24% of the total individuals, with the number of Acarina individuals 7.66 times than that of Collembola. The common group was Diptera. The results indicated that there was a distinctive vertical distribution of the soil animal communities in the forest litter layer, but it differed from that in soil below the litter layer. In contrast to those in the soil, the soil animals in the litter layer generally tended to increase in both group abundance and density from the top fresh litter layer to the bottom humus layer. Altogether 19 groups and 59.03% of total individuals were found in the bottom layer, while only 8 groups and 5.35% of the total individuals in the top. Moreover, there were some variations in the distribution of the soil animals at different plant succession stages. 85.19% of Homoptera and 100% of Symphyla were found in the litter layer at the climax succession stage, while 75.61% of Thysanoptera at the intermediate succession stage. Therefore, these groups might be seen as indicative groups. The total numbers of soil animal groups and individuals in the litter layers greatly changed in the succession process of the EBLF. They both were greatest at the climax, moderate at the intermediate and smallest at the primary succession stage. However, the main soil animal groups in the litter at the different succession stages were essentially the same. They were Acarina, Collembola, Diptera and Lepidoptera. Although similarity analysis revealed that the soil animal communities in the litter at the intermediate succession stage were most similar to those at the climax succession stage, they differed greatly from each other in the Shannon-Wiener diversity index. The Shannon-Wiener index was highest at the climax succession stage and lowest at the intermediate succession stage. Finally, the paper discusses the following three questions: the role of soil animals as indicators for plant community succession; the role of different soil animal groups in the litter decomposition at different stages; and the major factors affecting the composition and distribution of soil animals in the litter. This paper provides a new perspective for the research on the succession mechanism of plant communities and the decomposition functions of soil animals. __________ Translated from Acta Ecologica Sinica, 2005, 25 (3) [译自: 生态学报, 2005,25(3)]     

典型农田退耕后土壤真菌与细菌群落的演替

土壤真菌和细菌作为地下生态系统的重要组成部分,其群落的恢复状况是评价农田退耕还林生态效益的重要指标。以云南省维西县典型退耕还林农田为对象,利用高通量测序等方法比较了不同退耕年限的农田土壤中真菌和细菌群落随植被演替的变化特征。结果发现,农田撂荒后土壤细菌多样性先显著降低后缓慢上升,真菌多样性变化不明显;地上部植被由草本经灌丛再向林地演替的过程中,土壤真菌的群落组成随植被变化呈现明显的改变,主要体现在粪壳菌纲(Sordariomycetes)所占比例的减少(由30%减至10%左右)和伞菌纲(Agaricomycetes)所占比例的增加(由5%以下增至20%以上);而细菌的群落组成无明显变化。聚类分析的结果显示,真菌的群落组成变化与植物群落的演替规律更为同步。不同演替阶段的退耕农田土壤真菌和细菌群落均明显区别于未经扰动的天然林,表明人为扰动对土壤微生物群落的影响可能在较长时间内持续存在。研究揭示了云南典型农田退耕后地下土壤真菌和细菌群落随植被演替的变化特征,为全面评价该地区退耕还林的生态效益提供了数据支撑。     

采石场废弃地的生态重建研究进展

采石场的开采严重破坏了植被和土壤,形成了大量的裸露岩石斜坡,造成宏观景观支离破碎和极端的环境条件,限制了植物的生长。由于自然恢复所需时间长久,人工恢复被广泛应用于采石场废弃地的生态重建。自然演替过程是采石场生态重建的理论基础,自然演替理论可以为人工恢复措施提供指导。植物群落演替的早期阶段,非生物因素起主要作用,随着演替的推移,生物因素的重要性增强。邻近自然植被的土壤和繁殖体通过外力的扩散,对恢复起重要作用。除了非生物和其他的限制,先到达恢复地的物种竞争能力的变化能决定了演替过程。演替过程中的干扰因素往往成为演替重要的驱动力。裸露岩石斜坡的物理稳定性对植被恢复有重要影响,有机废物的使用和施肥可以影响恢复演替的方向和生物多样性。播种一定的植物能够改变恢复演替方向,加速演替过程。乡土物种适应了当地气候,能够促进演替。随着修复时间的延长,土壤有机质含量,植被覆盖度和物种丰富度不断增加,土壤微生物生物量随之增加。开展不同地区采石场植物种类的选育、研究乡土物种的功能特性、土壤微生物群落和酶的变化、植被演替过程的定位研究、植物种间的竞争关系、自然演替和人工恢复的比较研究、探索经济高效的采石场生态重建方法是未来的研究方向。     

黄土丘陵沟壑区撂荒地不同演替阶段植物群落的土壤抗蚀性——以坊塌流域为例

采用野外调查取样与室内试验相结合的方法,在分析土壤颗粒组成、级配状况与群体特性、团粒结构的分形特征及其稳定性变化的基础上,研究了黄土丘陵沟壑区撂荒地不同演替阶段植物群落的土壤抗蚀性.结果表明： 撂荒后植被从一年生草本群落阶段演替到多年生蒿禾类草本群落阶段的过程中,土壤的级配状况在不断改良,颗粒分形维数增大,团粒结构有所改善,土壤团粒结构的分形维数与结构体破坏率均不断减小,稳定性不断增强,从而提高了土壤的抗蚀性.实现植被的自然恢复对改善该区土壤结构、提高土壤抗蚀性、减少水土流失和促进区域生态环境可持续发展具有重要意义.     

Genetic diversity of nodulating and non-nodulating rhizobia associated with wild soybean (Glycine soja Sieb. & Zucc.) in different ecoregions of China

Microorganisms are important in soil development, inputs and biogeochemical cycling of nutrients and organic matter during early stages of ecosystem development, but little is known about their diversity, distribution, and function in relation to the chemical and physical changes associated with the progress of succession. In this study, we characterized the community structure and activity of nitrogen-fixing microbes during primary succession on a copper tailings. Terminal fragment length polymorphism (T-RFLP) and clone sequencing of nifH genes indicated that different N(2) -fixing communities developed under primary succession. Phylogenetic analysis revealed a diversity of nifH sequences that were mostly novel, and many of these could be assigned to the taxonomic divisions Proteobacteria, Cyanobacteria, and Firmicutes. Members of the Cyanobacteria, mostly affiliated with Nostocales or not closely related to any known organisms, were detected exclusively in the biological soil crusts and represented a substantial fraction of the respective diazotrophic communities. Quantitative PCR (and statistical analyses) revealed that, overall, copy number of nifH sequences increased with progressing succession and correlated with changes in physiochemical properties (including elementary elements such as carbon and nitrogen) and the recorded nitrogenase activities of the tailings. Our study provides an initial insight into the biodiversity and community structure evolution of N(2) -fixing microorganisms in ecological succession of mine tailings.