Ecological stoichiometry is an important index to reflect ecological interaction and the balance of various elements in ecological processes. At present, the stoichiometric spatial distribution of soil carbon (C), nitrogen (N), phosphorus (P) and potassium (K) in farmland and grassland of Inner Mongolia and its influencing factors are still unclear. In this study, the spatial distribution of soil nutrient content and stoichiometry and the effects of environmental factors on soil C:N:P:K stoichiometry were analyzed under different land use patterns in four agro-pastoral areas. The results showed that there was a geographical gradient in the ecological stoichiometric relationship between farmland and grassland. RCN, RCP, RCK, RNP and RNK showed an "N" distribution from west to east, while RPK showed a "V" distribution. The difference in spatial distribution was more significant than the difference in land use pattern. The ecological stoichiometric relationship of grassland was mainly affected by the content of C and N, and was related to the similarity of soil properties. The field ecological stoichiometry was mainly affected by the content of nitrogen and phosphorus, and had a great relationship with fertilization. The effects of MAT and MAP on soil ecological stoichiometry were related to the inter-regional environmental heterogeneity. The influence of MAP on farmland and MAT on grassland was more significant. It was of great significance for field management according to local conditions, rational utilization of land resources and sustainable development of agriculture to clarify the ecological stoichiometric characteristics of farmland and grassland in agro-pastoral ecotone.

Handmade papers, as carriers of paper-based cultural relics, have played a crucial role in the development of human culture, knowledge, and civilization. Understanding the intricate relationship between the structural properties and degradation mechanisms of handmade papers is essential for the conservation of historical documents. In this work, an artificial dry-heat accelerated ageing method was used to investigate the interplay between the mechanical properties of paper, the degree of polymerization (DP) of cellulose, chemical composition, hydrogen bond strength, crystallinity, and degree of hornification. The results show that the mechanical properties of handmade bamboo paper exhibited a first plateau region, a rapid decline region, and sometimes a second plateau region. A critical point in the mechanical properties of the paper occurs when the cellulose DP decreases to a range of 400-600, signifying a shift from the initial plateau to a sharp decline phase. The strengthening of intermolecular hydrogen bonds and the hornification process help counteract the embrittlement of fibers caused by cellulose chain scission due to DP reduction. A secondary plateau emerges when the DP is smaller than 400, cellulose degradation is slow, and the component content, hydrogen bond strength, crystallinity, and degree of hornification reach a secondary plateau.