The Addition of Exogenous Compost Humus Shortens the Composting Cycle of New Corn Stalks, Thereby Promoting Plant Growth

The treatment of straw biomass has always been a global issue. Although composting processes a large amount of straw biomass as a low-cost technology, its low efficiency has resulted in redundant stores of straw biomass. However, the humus in compost not only has an impact on soil fertility, but also has important effects on the functioning of microbial ecosystems. Meanwhile, the colloidal properties of humus can enhance the water and fertilizer retention capacity of compost, creating a suitable living environment for microorganisms. This study aimed to address the problems of the long composting periods and low maturity efficiency of corn straw by exploring the regulatory effect of exogenous compost humus on the composting process of corn straw and its promoting effect on plant growth. Composting treatment groups were set up with the addition of exogenous humus to systematically monitor the temperature changes, dynamic formation of humus, and change in microbial community during composting. The effects of compost products on corn growth were also analyzed through pot experiments. The results showed that the intervention of exogenous humus can significantly accelerate the composting process of corn straw, extend the traditional composting heating period by 8 days, and increase the humus content by 27.98 g/kg. It also increased the content of organic functional groups in the humus and significantly promoted the growth of corn, increasing its nitrogen content by 5.11 g/kg and increasing plant height and leaf length by 5 cm. This provides a new technical path for the efficient utilization of composting for corn straw. The treatment of agricultural waste and the production of high-quality organic fertilizers will promote the development of green agriculture.