The Effect Of Five Afforestation Modes On The Restoration Of Abandoned Soil In Tengzhou Coal Mine Area

In this paper,the changes of soil properties and heavy metal contents in Poplar,Gestationis Ligustrorum,Gestationis Ligustrorum× Poplar,scattered forests of Guttae dicitque,and Persici were studied based on different vegetation patterns of wasteland in coal mining areas of Tengzhou City.The effects of different vegetation restoration patterns on soil properties and heavy metals,as well as the relationship between vegetation recovery patterns were analyzed.The main findings are as follows:(1)The influences of different vegetation restoration modes on soil physical propertie showed that the soil pH of all restoration models were between 7.49 and 8.13,which were smaller than the bare grassland.All restoration models had different effects on soil organic matter,electrical conductivity and available nitrogen content.The Persici and Gestationis Ligustrorum had the highest and lowest conten of soil organic matter respectively,there was a significant difference between different modes.Vegetation restoration significantly reduced the soil conductivity,of which the Persici soil model had the highest soil electrical conductivity and was not conducive to plant nutrient absorption,there was a significant difference between different modes.The content of available nitrogen was significantly higher in Poplar than in other recovery modes.The available nitrogen content in Gestationis Ligustrorum was significantly lower than other recovery modes.(2)The influences of different vegetation restoration modes on soil enzyme activities showed that all restoration models had different effects on soil urease,sucrose,catalase and protease content,and there were significant improvements.The highest soil urease content was 1.65 mg/g of Gestationis Ligustrorum× Poplar,and the lowest was 0.82 mg/g of Gestationis Ligustrorum and 1.03 mg/g for Poplar,indicating that the mixed forest had a very good increase in soil urease activity effect.The soil sucrose content in the scattered forests of Guttae dicitque restoration model was the highest,the sucrose enzyme content in the Persici was the lowest,and the invertase content in the scattered forests of Guttae dicitque was twice that of the Persici.The content of catalase in the scattered forests of Guttae dicitque restoration model was also the highest,followed by the Persici,and the Gestationis Ligustrorum restoration model was the lowest.The content of soil protease in Poplar was significantly higher than that in the bare land,and the rest of the vegetation restoration models showed no significant difference in the bare land.(3)The influences of different vegetation restoration modes on heavy metals in soil showed that there were differences in Pt and Cr content in the five plant restoration models,which significantly reduced the soil heavy metal content.The soil Pt content in the scattered forests of Guttae dicitque restoration model was the highest,and the Poplar soil had the lowest Pt content,followed by the Gestationis Ligustrorum,and they were had the most significant improvement effect.The content of Cr in the Gestationis Ligustrorum × Poplar mixed forest soil was higher.The content of Cr in the Gestationis Ligustrorum forest soil was the lowest,followed by the Poplar pure forest.In general,the recovery patterns of Poplar and Gestationis Ligustrorum have a good improvement effect on heavy metal content in soil.Comprehensive analysis and evaluation of soil physicochemical properties,nutrients,enzyme activity,and heavy metal content in different recovery modes.Gestationis Ligustrorum× Poplar mixed forest model and Poplar pure forest restoration model out of the 10 indicators tested,the recovery effect is obvious,showing a good advantage.