摘要
废弃矿井生态修复既包含井工采煤沉陷造成的根系拉伤修复,也包含露天开采边坡地质灾害治理。废弃矿井受采矿影响致使生态脆弱,植株成活率低,生态修复成为矿山环境治理的主要目标。利用微生物修复技术恢复根系功能成为研究热点。为了深入揭示2类共生真菌丛枝菌根真菌(arbuscular mycorrhiza fungi,AMF)和深色有隔内生真菌(dark septate endophytes,DSE)对根系抗拉强度及根土复合体抗剪强度的影响,以紫花苜蓿为研究对象,布设室内盆栽实验,设置不种植物不接菌为纯对照CK1、种植植物不接菌为对照CK2、单接菌AMF、单接菌DSE和双接菌AMF+DSE 5种处理,研究接菌对根系力学特性及菌根复合土的抗剪强度影响作用。结果表明:接菌与对照处理的土壤粒径组成大致相同:细砂粒>中砂粒>粗砂粒,接菌前后土壤构成中粗砂粒所占比重增高,细砂粒含量成倍降低。5种不同处理下的平均单根抗拉力及复合体抗剪强度由大至小依次为AMF+DSE,DSE,AMF,CK2,CK1;平均单根抗拉强度依次为AMF+DSE,CK2,AMF,DSE。5种处理下深度10~20,20~30 cm处菌根复合土黏聚力比30~40 cm深度处的显著增加,黏聚力与根系分布相关;不同处理的根土复合体黏聚力均存在最优根径,即根径约为0.6 mm时黏聚力达到最大。该研究成果为微生物复垦机理提供了一种新的力学方法,为采煤沉陷地和地质灾害生物减损修复提供了一种新的思路。
Ecological restoration of abandoned mines includes root strain injury caused by underground coal mining and geological disaster prevention and control of open-pit slope.Abandoned mines have fragile ecology and low plant survival rate,so ecological restoration has become the main goal of mine environmental governance.Microbial remediation technology is used to restore root function,which has become a research hotspot.In order to reveal the effects of two symbiotic fungi,arbuscular mycorrhiza fungi(AMF)and dark septate endophytes(DSE),on the tensile strength of roots and the shear strength of root-soil composite,the Medicago sativa was taken as the research object.The indoor pot experiment was conducted,and five treatments were set:control CK1 without plant and fungus inoculation,control CK2 with plant and no fungus inoculation,AMF with simple fungus inoculation,DSE with simple fungus inoculation and AMF+DSE with double-fungus inoculation.The effect of fungus inoculation on the root mechanical properties and shear strength of mycorrhizal composite soil was studied.The results showed that the grain size composition of soil inoculated with bacteria in control treatment was almost consistent:fine sand>medium sand>coarse sand.The proportion of coarse sand in soil composition increased and the content of fine sand decreased exponentially before and after inoculation.The average tensile strength of single root and shear strength of composite under five different treatments from high to low were as follows:AMF+DSE>DSE>AMF>CK2.The average tensile strength of single root from high to low was as follows:AMF+DSE>CK2>AMF>DSE.The cohesive force of mycorrhizal composite soil at different depths of 10-20 cm and 20-30 cm was significantly higher than that at depths of 30-40 cm under five treatments,and the cohesive force was related to the distribution of root system.There was an optimal root diameter for the cohesion of root-soil composite with different treatments,namely the cohesion reached the maximum when the root diameter was about 0.6 mm.The research results provide a new mechanical method for microbial reclamation mechanism,and a new idea for biological impairment and restoration of underground coal mining and geological disasters.
作者
毕银丽
罗睿
王双明
BI Yinli;LUO Rui;WANG Shuangming(Shaanxi Key Laboratory of Geological Support for Coal Green Exploitation,Xi’an University of Science and Technology,Xi’an 710054,China;State Key Laboratory for Coal Resources and Safe Mining,China University of Mining and Technology-Beijing,Beijing 100083,China)
出处
《煤炭学报》
EI
CAS
CSCD
北大核心
2022年第6期2182-2192,共11页
Journal of China Coal Society
基金
国家自然科学基金资助项目(51974326)
首都科技领军人才资助项目(Z18110006318021)。
