先锋修复植物对土法炼锌废渣基质养分及微生物学特性的影响

Effect of Pioneer Phytoremediation on Indigenous Zinc Smelting Slag Matrix Nutrients and Microbial Properties

为综合评价先锋修复植物对黔西北土法炼锌废渣基质的生态修复效应,通过野外采样及室内分析研究改良的土法炼锌废渣上自然定居植物土荆芥(Chenopodium ambrosioides)和大叶醉鱼草(Buddlejia davidii)以及先锋修复植物白三叶草(Trifolium repens)和黑麦草(Perennial ryegrass)对废渣基质的养分、酶活性及微生物活性的改善效果。结果表明:与无植被修复的裸露废渣相比,4种修复植物具有明显的根际效应,表现为根际废渣pH值降低,且4种修复植物可显著(p<0.05)增加根际废渣基质的养分(N,P,K、有机质)、酶活性(脲酶、蔗糖酶、磷酸酶、过氧化氢酶)、微生物活性(细菌、真菌、放线菌、微生物量、呼吸作用强度)。相关性分析表明,植物根际废渣养分、酶活性和微生物活性之间总体上呈正相关关系,其中有效氮与蔗糖酶和磷酸酶之间,全氮与细菌之间均呈极显著(p<0.01)相关,而有效钾与呼吸作用强度、微生物量和真菌之间,真菌与脲酶和蔗糖酶之间及微生物量与脲酶、蔗糖酶、磷酸酶、过氧化氢酶之间均呈显著相关(p<0.05)。通过主成分分析计算的综合肥力指标表明,三叶草修复铅锌冶炼废渣基质的综合肥力最高,而无植被存在的裸露废渣肥力指标最低。可见,在4种先锋修复植物中,三叶草作为先锋植物对土法炼锌废渣基质的修复效果最好。因此,在土法炼锌废渣堆场生态修复过程中,可选择三叶草作为先锋植物显著改良炼锌废渣的植生特性,为在废渣堆场上快速引进其他植物提供了有利条件。

In order to comprehensively evaluate the effect of ecological restoration of pioneer restoration plant on indigenous zinc smelting slag matrix,in northwest Guizhou.Through field sampling and laboratory analysis,the improvement effect of modified natural colonized plants（Chenopodium ambrosioides,Buddlejia davidii）and pioneer restoration plants（Trifolium repens,Perennial ryegrass）on residue matrix nutrient,enzyme activity and microbial activity was examined.The results showed that four pioneer restoration plants presented an obvious rhizosphere effect compared with the exposed slag without vegetation restoration,performance of rhizosphere slag decreased pH,and significantly increased（p 0.05）residue matrix nutrients（N,P,K）,organic matter,enzyme activities（urease,invertase,phosphatase,catalase）,microorganism（bacteria,fungi,actinomycetes,microbial biomass,respiration intensity）of rhizosphere.Correlation analysis showed thatresidue matrix nutrients,enzyme activities and microbial activity of the four plants rhizosphere were positively correlated in general,the residue matrix available N was significantly correlated with residue matrix invertase and phosphatase,total nitrogen was significantly correlated with bacteria（p〈0.01）.Available K had significant correlations with actinomycetes,microbial biomass and fungi,fungi had significant correlations with urease and invertase,microbial biomass was significant correlated with urease,invertase,phosphatase and catalase（p〈0.05）.The results of principal component analysis showed that,the fertility of zinc smelting slag matrix repaired by Trifolium repens was the highest,the control was lowest.Obviously,Trifolium repens as to the repair effect of pioneer plant wastes residue matrix was the best in the four pioneer restoration plants.Therefore,in the process of ecological restoration of indigenous zinc smelting slag yard,using Trifolium repens as the characteristics of planting pioneer plants could significantly improve the zinc slag,provides favorable conditions for the rapid introduction of other plants in the waste residue yard.