Difference Of Soil Fertility And Fungal Diversity In Different Tree-species Types Of The Urban Forest

Urban Forestry plays an important role in improving citizen’s living environment, making the city much beautiful, cleaning air, reducing the urban noise, regulating the ecological balance of the urban environment. Urban forestry soil is a vital component of the urban forest ecosystem, which also is the most effective cleaner of the urban environment. In urban forestry soil ecosystem, the soil microbes are the main decomposers of plant and animal residues. They undertake the important function in the process of material recycling and energy conversion in soil ecosystem. It has great significance to study the impact of soil fertility and soil microbial community structure on different plantations of the urban environment. This study enables to provide the basic data for people to deep understand urban forestry, to rational utilize the urban forestry soil resources and to bring out the ecological, social and economic benefits of the urban forestry.8artificial pure forest from the Urban Forestry Demonstration Base of the Northeast Forestry University including Juglans mandshurica Maxim., Fraxinus mandshurica Rupr., Phellodendron amurense Rupr., Be tula platyphylla Suk., Larix gmelinii (Rupr.) Rupr, Pinus sylvestris var. mongolica Litv., Pinus tabulaeformis var. mukdensis and Picea koraiensis Nakai were selected as the sample plot. The surrounding meadow was selected as the control. The soil samples were collected from the soil in0-15cm depth. Soil samples treated with2mm sieve were brought back to the lab. Soil fertility index including soil water content, pH, conductivity, soil invertase activity, phosphatase activity, urease activity, polyphenol oxidase activity, fluorescein diacetate esterase activity, soil bacterial number, actinomycetic number, fungal number were measured. And high-throughput sequencing of soil fungal ITS sequences was put into practice. The impact of the urban forestry with different tree species composition on the soil fertility and soil fungal community diversity was evaluated.Soil fertility index significantly differ among different urban forest types. There are also significant differences among different broadleaf forest types, and among the coniferous forest types. And the significant correlation existed among the soil fertility indicators such as the basic physical and chemical indicators, soil enzyme activity and microbial biomass. The result showed that the soil organic carbon, nitrogen and phosphorus accumulation and transformation capabilities as well as the soil microbial activity of the three hardwood forests were higher than that of other forest types. Soil fertility and microbial biomass of the broadleaf forests were higher than that of the coniferous forests, and the soil humic degree lower than that of the coniferous forests.Cluster analysis showed that five groups have been devided for all forest soil, J. mandshurica clustered with F. mandshurica, P. amurense clustered with B. platyphylla, P. sylvestris clustered with P. tabulaeformis and L. gmelinii, P. koraiensis and the control independently grouped.High-throughput sequencing analysis of soil fungal ITS sequences showed that8fungal Phylum,24Classes,63Orders,124Families,211Genuses,362Species were detected from9samples. Fungal Phylum includes the Ascomycota, Basidiomycota, Chytridiomycota, Zygomycota, Glomeromycota. In addition, this study only detected Archaeorhizomycetes from P. tabulaeformis forest soil, Agaricostilbomycetes from the control soil, Glomeromycota from J. mandshurica and F. mandshurica forest soil, Exobasidiomycetes from the control and P. koraiensis forest soil. Cluster by the fungal abundence and diversity in fungal Phylum was similar with the result by the soil fertility and microbial structure. The difference is that P. sylvestris and P. koraiensis clustered with J. mandshurica and F. mandshurica, but not the other two coniferous forests. The reason need to be studied in the future.Ascomycota is the fungal dominant community in the J. mandshurica, F. mandshurica, L. gmelinii and P. sylvestris forest soil. Basidiomycota is the fungal dominant community in P. amurense, B. platyphylla, P. tabulaeformis and P. koraiensis forest soil on the fungal Phylum classification level. Agaricomycetes is the fungal dominant community in almost of all forest soil, except Sordariomycetes is the fungal dominant community of the F. mandshurica forest soil. Soil fungal community abundance and diversity are significant differences among different plantations by Ace, Chao, Shannon and Simpson index evaluation. There was significant correlation between the fungal abundance in fungal Phylum classification and soil fertility index.