煤矸山复垦林地、草地土壤生态肥力差异分析

Difference in Soil Ecological Fertility between Reclaimed Woodland and Grassland in a Coal Waste Pile

土壤生态肥力不仅能反映土壤为植物生长提供水、肥、气、热的能力,还可反映土壤健康状况和可持续利用的能力,故能够用于煤矸山复垦地土壤质量评价。以山西省长治市潞安矿区植被复垦后8年的煤矸山为研究对象,比较了复垦为林地和复垦为草地的0~10 cm和10~20 cm土层土壤生态肥力的差异,并分析其原因。结果表明:(1)复垦林地土壤碱解氮和有效磷含量,微生物量碳和氮含量,碱性磷酸酶活性,微生物群落PLFA总浓度和细菌、真菌、放线菌和革兰氏阳性菌群落PLFA浓度均明显高于复垦草地,而土壤微生物丰富度指数、Shannon-Weiner指数低于复垦草地。(2)土壤生态肥力评价结果表明,复垦林地土壤生态肥力水平优于复垦草地,这主要缘于复垦林地中较强的根系作用和较多的根系分泌物形成了有利于营养物质迁移转化以及微生物和酶生长的土壤微环境。本研究可为煤矸山复垦植被的选择和复垦地后期管理提供科学依据。

Soil ecological fertility not only reflects the ability of soil to provide moisture,nutrients,gas and heat for plant grouth,but also indicates soil health and sustainable use performance.Therefore,it can be used to evaluate the soil quality of the reclaimed land in coal waster pile.The differences in soil ecological fertility were analyzed between woodland and grassland after been reclaimed 8 years at 0-10 and 10-20 cm soil layers in Lu’an mining coal waste pile in Changzhi,Shanxi Province,and the reasons of the differences also were analyzed.The results showed that:(1)The contents of soil available nitrogen(AN),soil available phosphorus(AP),soil microbial biomass carbon(MBC)and soil microbial biomass nitrogen(MBN),were higher in reclaimed woodland than that in reclaimed grassland,significantly,it has the same trend in the activities of alkaline phosphatase,the total microbial community PLFA,the bacteria,fungi,actinomycetes and gram positive bacteria PLFA concentration but not in the soil microbial richness index(S)and Shannon-Weiner index(H).(2)The results of soil ecological fertility evaluation showed that soil ecological fertility was higher in the reclaimed woodland than that in reclaimed grassland.This is mainly due to the strong root action and more root exudates in reclaimed woodland,which benefit to migration and transformation of nutrient as well as microbial and enzyme growth in the soil micro-environment.This study will provide a scientific basis for vegetation type selecting and suggestion for management after planting in reclaimed land in coal waste pile in China.