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Straw incorporation increases the amount of nutrients in soil and greatly impacts soil nitrogen and microbial communities. In this study, 15N‐labeled corn straw was used as the material, the experiment consisted of five treament (AS: placing the straw 15 cm above the soil surface, SM: using the straw to mulch the soil surface, B15: burying the straw 15 cm below the ground surface, B30: burying the straw 30 cm below the ground surface, B45: burying the straw 45 cm below the ground surface). The changes in 15N abundance in straw were analyzed. An estimation method for nitrogen release and uptake by field‐incorporated straw was proposed, and the relationships between nitrogen release and uptake and related microbes were established. The results showed that the exchange of nitrogen between maize straw buried in soil at different depths and the environment was not significant. The corn straw exposed to the air absorbed more nitrogen from the environment in the second year of decomposition, and the larger the area exposed to the air was, the more nitrogen was absorbed from the environment. The relative abundances of Burkholderiales, Flavobacteriales, Pseudomonadales, and Sphingobacteriales were significantly positively correlated with the straw decomposition rate and nitrogen release rate. The relative abundance of Rhizobiales was significantly negatively correlated with the straw decomposition rate and nitrogen release rate. The relative abundances of Sphingobacteriales, Flavobacteriales, and Pseudomonadales were significantly negatively correlated with the straw nitrogen uptake rate. [ABSTRACT FROM AUTHOR]

Based on the systematic sampling and analysis of the four drill cores in the exploration line 18 of Huangtun copper-gold deposit in Lujiang, Anhui Province, this paper studies the geological characteristics and primary halo zoning characteristics of the exploration line18, preliminary summarizes the geo chemical anomaly pattern of the deposit, and explores the possible genesis of Huangtun copper-gold deposit. Au, Ag, Cu, As, Sb, Bi and W are the characteristic element assemblage of Huangtun copper-gold deposit, and the vertical zoning sequence of the primary halo of this deposit is (Sb, As)-(Ag, Au, Cu)-(Bi, W). The geological characteristics and primary halo morphology of the exploration line 18 show that there may be a hidden fault between the borehole ZK18-1 and ZK18-2, resulting in dislocation of copper-gold ore body and stratum. Element association anomaly of front halo in hydrothermal deposit is developed at the bottom of borehole TK02, indicating that there may be concealed ore bodies in the deep. The comprehensive study shows that the ore-forming materials of Huangtun copper-gold deposit may be mainly derived from volcanic hydrothermal and diorite porphyrite, and this deposit belongs to volcanic-sub volcanic hydrothermal type. [ABSTRACT FROM AUTHOR]