关键词: 城市建设, 建筑废弃物, 土壤养分, 微生物群落

Abstract: To clarify the impacts of stockpiled construction waste on soil environment of coastal cities, five land use types were selected: construction waste stored for six months, construction waste stored for 12 months, wasteland, long-term cultivated farmland and re-cultivated farmland in Lingkun City, Wenzhou, Zhejiang Province. We analyzed the differences and correlations of soil environmental factors and microbial community structure in different habitats. The results showed that the accumulation of construction waste significantly increased soil pH and decreased the concentrations of organic carbon, active organic carbon, total nitrogen, organic nitrogen, active organic nitrogen and hydrolyzed nitrogen. With the accumulation of construction waste, the composition of soil microbial community changed, and Proteobacteria and Firmicutes replaced Actinobacteriota as the dominant phyla. The variation of soil environmental factors caused by the accumulation of construction waste reduced soil microbial abundance. The redundancy analysis results showed that soil pH, salt, total nitrogen, total phosphorus, and dissolved organic carbon contents were the main factors influencing of soil microbial community. Re-cultivation helps restore soil environmental factors and microbial community composition. This study contributes to better understanding of the impacts of construction waste on the environment and the microbial mechanism in the process of urbanization, and demonstrates the positive effect of re-cultivation as a means of restoration on the damaged soil environment.

Key words: urban construction, construction waste, soil nutrient, microbial community