摘要
尾矿废弃地是一种人为的裸地,其自然生态恢复过程表现为典型的生态系统原生演替过程。尾矿废弃地自然生态恢复过程为人们了解生态系统发展过程中土壤微生物群落的变化提供了一个良好的机遇。该研究以2处(即,铜陵杨山冲尾矿废弃地和铜官山新尾矿废弃地)不同时期弃置的、处于3个演替阶段(原生裸地阶段、隐花植物结皮阶段和草本维管植物群落阶段)的铜尾矿废弃地为研究对象,利用传统培养法(稀释平板法)和分子生物学法(净DNA含量法)相结合的手段对土壤微生物量和土壤微生物群落结构变化及其影响因素进行了调查。数据分析表明:随着尾矿废弃地上植物群落的形成和发展,尾矿废弃地水分含量增加、pH降低、土壤有机质和总氮质量分数提高;土壤微生物数量逐渐增加,维管植物群落下的尾矿废弃地中土壤微生物数量明显高于处于演替初期阶段的隐花植物结皮,高于裸地;不同演替阶段尾矿废弃地中土壤微生物群落结构表现为细菌(60.68﹪～97.45﹪)>放线菌(2.50﹪～39.13﹪)>真菌(0.05﹪～0.82﹪);相关分析发现,尾矿废弃地土壤微生物量变化与基质的含水量、总氮和有机质质量分数呈正相关,而与pH变化呈负相关。研究结果表明,在尾矿废弃地自然生态恢复过程中,伴随着植物群落形成、发展和基质理化性质的逐步改善,尾矿中土壤微生物也逐步恢复。
Copper mine tailings wastelands are a kind of man-made barren. The ecosystem development on the tailings wastelands is a primary succession, which provides a good opportunity for understanding the changes of soil microbial communities during the primary ecosystem succession. In order to investigate the succession of soil microbial community with ecosystem development, soil samples of three successional stages （i.e., barren stage, cryptogamic crust stage and herbaceous vascular plant community stage） from two tailings wastelands （Yangshanchong tailings wasteland discarded in 2001 and New Tongguanshan tailings wasteland discarded in 1991 ） were collected and soil microbial biomass was detennined by methods of typical plate culture and molecular biology （net DNA content）. The data analysis showed that the content of water, soil organic matter and total nitrogen in tailings wastelands increased with formation and development of plant communities. However, pH value of tailings wastelands decreased with ecosystem development. The change of soil microbial biomass at different successional stages displayed the following order： barren stage 〈 cryptogamic crust stage 〈 herbaceous vascular plant community stage. And component of soil microbial communities in natural ecosystem succession showed the following order in proportion： bacteria （60.68 % - 97.45 % ） 〉 actinomyces （2.50 % - 39.13 % ） 〉 Fungi （0.05 % - 0.82 % ）. The correlation analysis indicated that soil microbial biomass was positively correlated to contents of water, soil organic matter and total nitrogen in tailings wastelands and was negatively correlated to pH value of tailings wastelands. It can be concluded that soil microbial community in tailings wastelands is gradually restored with formation and development of plant communities on tailings wastelands and improvement of physico-chemical properties of tailings wastelands.
出处
《生态环境》
CSCD
北大核心
2008年第2期713-717,共5页
Ecology and Environmnet
基金
安徽省自然科学基金项目(070415208)
国家高技术研究发展计划(863)项目(2006AA06Z359)
关键词
铜尾矿
废弃地
原生演替
土壤微生物
copper mine tailings
wasteland
primary succession
soil microbes
