Abstract:

In order to explore the effects of garden waste compost and biochar soil conditioner on the quality of coastal saline soil, the control group (CK), green waste compost treatment group (GW) and biochar treatment group (BC) were set up. The results showed that: in terms of seed germination index, biochar treatment was superior to composting treatment, in which the soil seed germination index of composting treatment was 88%, which was 21 percentage points higher than that of the control group (67%), and the soil seed germination index of biochar treatment was 96%, which was 29 percentage points higher than that of the control group. In terms of soil physical properties, composting treatment significantly increased the maximum water holding capacity, capillary water holding capacity, capillary porosity and infiltration rate, and reduced the mass moisture content and non capillary porosity; Biochar treatment significantly increased soil bulk density, mass moisture content and infiltration rate, but decreased the maximum water holding capacity, capillary water holding capacity, capillary porosity and total porosity. In terms of soil chemical properties, composting treatment significantly increased soil organic matter, total nitrogen content and carbon nitrogen ratio, while reducing pH value and electrical conductivity (EC); Biochar treatment significantly increased soil organic matter, total nitrogen content, carbon nitrogen ratio and pH value, and decreased EC value. The results reveal the mechanism of the two amendments, and provide theoretical basis and technical support for soil quality improvement in salinized areas.

Key words: saline soil, garden waste composting, biochar, soil properties, Shanghai