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[Objective] This study investigated the effects of two self-developed Bacillus solid inocula (B01 and B02) and their compound agent (SB012) on green waste compost to encourage the application of solid inocula. [Method] Five treatments including blank treatment without adding bacteria (CK), solid baceria B01, B02 and SB012 as well as liquid bacteria EM, which is widely regarded as the best on the market, were applied to the plant residues artificially pruned or naturally withered from Beijing Fragrant Hills Park as raw materials for composting. The solid bactericide SB012 was created by combining B01 and B02 with mass ratio of 3 : 1. After inoculation, heap temperature was measured at 12:00 once per day. The samples were collected every 7 days to determine pH, electrical conductivity (EC), germination index (Gl), humic extract, contents of humic acid and fulvic acid, ratio of humic acid to fulvic acid, and contents and relative degradation rates of lignin and cellulose in different compost treatments and the effects of B01, B02 and SB012 on composting process were evaluated. [Result] Over time, the temperature of compost under different treatments increased first and then decreased. Compared with CK, the addition of B01, B02, SB012 and EM romoted the green waste heaps to enter the high temperature stage in advance. The peak temperatures of B01 and SB012 composts reached 72.1 and 70.2 °C, both were higher than EM and CK. The EC decreased after initial increase, while the pH of the compost increased throughout all treatments. At the end of composting process, all treatments had a pH greater than 8.0 and their EC ranged from 0.76 to 1.04 mS/cm, all of which met the national standards for green waste compost products. The GI increased first and then dereased under different treatments, and the GI order of the three kinds of solid inocula at the end of composting was SB012>B01>B02, which will all higher than that of EM and CK, reaching the standard of no toxicity to plants (≥85 %). Among the five treatments, the highest relative degradation rates of lignin and cellulose were 56.85% and 79.84% in SB012 treatment, which were significantly higher than EM treatment and CK treatment. [Conclusion] The SB012 bactericide had the best promotion for cellulose and lignin components in landscaping waste compost with the advantages of excellent quality and safety. [ABSTRACT FROM AUTHOR]

Large amount micromolecule organic matters and saline ions was produced during the composting from green wastes, leading to low pH value and high electrical conductivity (EC), and so on. These problems will hurt the seedling in the course of cultivation. In order to increase the effective use of green waste and improve the quality of growing substrate, 2 kinds of ameliorants, including bamboo vinegar (the dilution ratio of 500 or 1 000, the addition content of 500 mL/g ) and medical stone (the addition content of 20, 40, 80 g/kg), were applied into green waste composting. Seed germination parameters, seedling growth, substrate pH value and EC, were measured as screening indexes to screen out their proportioning for effectively ameliorating growing substrate. The results showed that the addition of bamboo vinegar and medical stone decreased pH value and EC of green waste compost substrates effectively. Compared with the control, bamboo vinegar and medical stone addition decreased pH value by 1.15-1.20 and EC by 1 839-2 076 μS/cm in growing substrate. The addition of bamboo vinegar and medical stone had very significant effect on seed germination, and largely increased germination percentage, germination potential, germination index and vigor index. Compared with the control, germination percentage, germination potential, germination index and vigor index of the treatment E (1 000 times 500 mL/kg dilution bamboo vinegar + 40 g/kg medical stone) were higher by 41.66%, 44.99%, 9.70, 99.75. The treatments with the addition of bamboo vinegar and medical stone promoted seedling growth, and also increased chlorophyll contents, which accordingly increased the root weight, root length and seedling weight. The root length, chlorophyll content, plant height and seedling weight were high than the control by 4.01 cm, 0.3375 mg/kg, 0.139 g and 1.380 cm, respectively. Therefore, the treatments of applying 500 mL/kg 1 000 times dilution bamboo vinegar + 40 g/kg medical stone to the green waste compost substrates has the best effect. The results of the study will promote green waste compost waste used as substrate utilization. [ABSTRACT FROM AUTHOR]