Abstract:

Objective: Through the selection and combination of composite microbial agents with significant synergistic and synergistic effects, the forest litter can be rapidly degraded, thereby significantly reducing combustibles such as dead branches and leaves under the forest, to enhance the fire prevention efficiency of the fireproof forest belt and further degrade litter into organic fertilizers. Method: A test plot was set up in the experimental forest farm of Jiangsu Academy of Forestry in the southern suburb of Nanjing. Based on a previous experimental result that there were the synergistic and synergistic effects of single strain, dual-strain combination, and composite microbial agents on litter degradation, the organic matter content and degradation rate were determined by burning at 550 ℃, and the maturation of the heap was evaluated by small rape seed germination index method. The temperature, moisture content, and pH value of different composite microbial agents on litter degradation of fermented piles were determined by setting up a tank experimental pile area and a forest experimental area, and the most suitable amount and time of composite microbial agents were selected to evaluate the degradation effect. Result: The order of temperature change in the litter degradation fermentation heap of fireproof landscape tree species was compound microbial agent Ⅰ> compound microbial agent Ⅱ> dual microbial agent Ⅲ> control CK. With the increase of treatment time, the water content and organic matter content of microbial agent Ⅰ treatment decreased the fastest, the pH value changed the most actively, and the organic matter degradation effect (P<0.05) was the most obvious, followed by other treatments. The results of 4 factors and 4 levels orthogonal test showed that microbial agent Ⅰ had a significant synergistic and synergistic effect on the degradation rates of litter. The degradation rates of litter by different compound microbial agent Ⅰ, Ⅱ, double microbial agent Ⅲ and CK treatment were 92.3%, 82.7%, 62.1% and 25.5%, respectively, and there were significant differences in the degradation rates of litter between the compound microbial agents and the control (P<0.05). On June 10, the degradation rate of understory litter reached 100% after 30 days of treatment with 30 kg·hm^?2 compound microorganisms I, which was both efficient and economical. After 30 days of treatment, GI of compound microbial agent Ⅰ,Ⅱ and double microbial agent Ⅲ was 98.2%, 92.3% and 89.7%, respectively, which all exceeded the harmless level of GI>80% maturation (P<0.05). Conclusion: The treatment of microbial agent I can rapidly degrade the litter of tree species in fire-resistant landscape and achieve the goal of reducing understory combustible materials.

Key words: compound microbial agent, fire protection landscape tree species, dead branches and leaves litter, degradation effect, turn harm into fertilizer