Tingting Song

Rural heating renovation in Jilin Province requires systems that suit regional conditions while balancing household costs and indoor thermal conditions. This study combined a survey of 276 rural households with TRNSYS multizone simulations to assess five heating configurations in Yanji, Changchun, and Baicheng, China. Survey findings informed case selection, while simulations evaluated energy consumption, indoor temperatures, solar contribution, and life-cycle costs over a 4392 h heating season. Under the adopted operating conditions, floor heating configurations consumed 8.2% less biomass in Yanji and 13.0% less electricity in Changchun than their radiator counterparts. These reductions coincided with lower indoor temperatures and, therefore, reflect differences in complete system configurations and controls, rather than in emitter type alone. In Baicheng, useful solar heat supplied 28.3% of seasonal heat delivery, although biomass remained the principal heat source during the coldest months. Discounted costs over 15 years ranged from USD 5411 to USD 11,127, and sensitivity analysis identified relative installation costs as a key determinant of economic rankings. By linking household survey evidence with energy, economic, and hourly temperature assessments, this study provides a basis for regional heating decisions that account for local energy availability, household costs, and the indoor conditions provided.

Straw returning methods and decomposing inoculants can jointly affect soil microbial communities and their functional potential. However, the differences in microbial responses under different straw returning methods remain unclear. In this study, a 180-day incubation experiment was conducted to compare the effects of straw mulching, shallow tillage, and deep tillage, with or without decomposing inoculant addition, on soil properties, microbial communities, CAZy families, and KEGG pathways. The results showed that straw mulching maintained the highest soil moisture content, reaching 19.31%. Under shallow tillage with inoculant addition, soil total organic carbon reached 27.31 g/kg, representing an 18.58% higher than in CK. This treatment also showed relatively high microbial community richness and diversity, with enrichment of Candidatus_Nitrosocosmicus, Clostridium, and Sphingobacterium. Under deep tillage with inoculant addition, soil total nitrogen reached the highest value of 1.227 g/kg, and Limnobacter, Candidatus_Nitrosotalea, and Sanguibacter were enriched. Additionally, inoculant addition was associated primarily with changes in GT and CBM families and amino acid biosynthesis-related pathways under shallow tillage, but with changes in CE and GH families and nitrogen metabolism-related pathways under deep tillage. Soil moisture was significantly associated with community composition, while total nitrogen and available nitrogen were significantly associated with KEGG functional profiles. Overall, the effects of decomposing inoculant addition on soil nutrients, microbial communities, and functional profiles varied across straw returning methods. Soil moisture and nitrogen availability emerged as important factors associated with these microbial and functional differences.