Abstract:

Effect of mulching greenery waste on soil fertility of municipal forest land was studied. Result showed that greenery waste mulching reduced soil bulk density, improved water retention capacity of soil, and increased soil total porosity, capillary porosity, and especially non-capillary porosity. In the range of mulching amounts (6 120 kg·hm^-2) applied in this experiment, mulching also significantly enhanced contents of organic matter, total nitrogen, total phosphorus, hydrolyzable nitrogen, available phosphorus and available potassium in soil, and the amount of mulch had a remarkable positive correlation with these soil critical nutrition indexes. However, the increase of total potassium was not observed until 160 days after the treatment with high amount of mulch. The mulch also significantly raised the contents of microbial biomass carbon and microbial biomass nitrogen, accelerate microbial turnover rate, shorten microbial turnover time, increase microbial transfer capacity and activate soil microbial activity, which was beneficial to recycling and maintaining soil fertility. Microbial biomass carbon and microbial biomass nitrogen had a significant positive correlation with the soil critical nutrition indexes, which could be used to evaluate the remediation efficiency of mulching greenery wastes on land. The mulching of greenery wastes had a positive role in improving soil quality and reducing maintenance costs for green space which was favor to constructing the economical landscape and gardening for the urban.

Key words: greenery wastes, mulching, urban forest land, soil fertility, microbial biomass