3种草本植物对粉煤灰堆场介质理化与生物学特性的影响

Effects of Three Herb Communities on Physicochemical and Biological Characteristics of Rhizosphere Medium in Coal Ash Dump Site

为研究不同草本植物恢复对电厂粉煤灰堆场的生态修复效果，采集堆场上生长的白茅（Im—peratacylindricaBeauv）、白三叶（Trifolium）和蕨（Pteridiumaquilinum）3种草本植物群落下0～70cm的粉煤灰介质，分析其综合理化特性和主要的土壤生物学指标。结果表明：3种草本植物均可有效改善堆场粉煤灰介质的水分状况，同时能改变粉煤灰的pH、EC、Eh等理化性状，进而影响堆场的适生生境。相对于对照，3种草本植物的存在可显著提高粉煤灰介质的脂磷微生物量、呼吸强度以及过氧化氢酶、脲酶、磷酸盐转化酶活性，显著改善堆场粉煤灰介质的生物学特性。堆场垂直剖面对比分析表明，除粉煤灰的含水率和PH随深度增加而呈上升趋势外，其他理化指标与生物学指标都随粉煤灰堆场深度的增加呈显著降低趋势，植物对粉煤灰理化特性与生物学特性所产生的影响也越来越小，并在不同植物种群之间呈显著差异。

In order to investigate the ecological restoration effect of different herb communities on power plants coal ash dump sites, coal ashes from the rhizosphere of 3 herbs （Irnperata cylindrica Beauv, Trifoliurn and Pteridiurn aquilinurn） communities with height from 0 to 70 cm were chosen as quadrats, and coal ash without vegetation cover was taken as control. Physicochemical properties （moisture content, pH, EC and Eh） and biological characteristics （lipid-p, respiration intensity, CAT, urease and AP） in coal ash samples were used to study the ecological restoration effect of herbs recovery in coal ash dump site. The results showed that all herbs improved the physical and chemical properties of coal ash, therefore directly affected the dump site as habitat of herbs. Lipid-p content and respiration intensity of coal ash which with plants cover were higher than control. The presence of plants in coal ash dump site also significantly improved transformation activities of CAT, urease, and phosphate invertase. Except the moisture and pH of coal ash increased along with the depth increased, other physicochemical and biological indicators were inversely correlated with the depth of coal ash, the impact of plants on both physicochemical and biological characteristics got smaller, and there were significant differences among different herb communities.