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Miscanthus spp. are increasingly cultivated in cropland worldwide due to their bioenergy potential and multiple ecological services. Effects of long‐term cropland‐to‐Miscanthus conversion without N fertilizer on soil microbiome and N cycling largely remain unknown. We aimed to explore the effects of Miscanthus conversion on soil microbiome and N cycling over a 15‐year period. We analyzed diversity, composition, and abundance of bacterial and archaeal communities using 16S rRNA amplicon sequencing, and abundances of N‐cycling‐related genes using quantitative polymerase chain reaction of 0–10 cm soils collected from bare land, cropland, 10‐year Miscanthus × giganteus, and 15‐year Miscanthussacchriflorus land in Beijing. Conversion decreased soil sand and micro‐aggregate proportion, nitrate N (NiN), available phosphorus levels, conductivity, temperature, and pH, while increasing proportion of soil clay and macro‐aggregate (MAA), soil organic C (SOC), available N (AN), exchangeable Mg2+ (EMg2+), and available potassium (AK) contents as well as microbial C/N. Consequently, diversity, composition, and abundance of soil bacterial community exhibited larger changes than those values of archaeal community after conversion. Soil AP, EMg2+, AK, and SOC were key factors in shifting microbiome from the cropland to Miscanthus pattern. Moreover, abundances of bacterial and archaeal communities and the N fixer gene nifH increased, whereas that of the bacterial ammonia monooxygenase gene decreased. The copies of other N‐cycling‐related genes in the two Miscanthus lands seemed similar to those values of cropland. The nifH copies negatively correlated with soil NiN and positively correlated with AN, EMg2+, ECa2+, SOC, AK, and MAA. We conclude that changes in soil microbiome pattern induced by the variation of soil properties enhance microbial N fixation potential, maintaining stable N levels and robust N cycling with lower N leakage risk after conversion. These results should inspire farmers and governments to large‐scale use Miscanthus on marginal cropland in Northern China. [ABSTRACT FROM AUTHOR]

To better understand how warming, increased precipitation and their interactions influence community structure and composition, a field experiment simulating hydrothermal interactions was conducted at an annual forb dominated desert steppe in northern China over 2 years. Increased precipitation increased species richness while warming significantly decreased species richness, and their effects were additive rather than interactive. Although interannual variations in weather conditions may have a major affect on plant community composition on short term experiments, warming and precipitation treatments affected individual species and functional group composition. Warming caused C4 grasses such as Cleistogenes squarrosa to increase while increased precipitation caused the proportions of non-perennial C3 plants like Artemisia capillaris to decrease and perennial C4 plants to increase. [ABSTRACT FROM AUTHOR]

Cover cropping is widely used for soil management in vineyards. But few studies have compared the effect of different cover cropping management methods on soil properties and fungal communities in vineyards. Therefore, we examined the effects of traditional management (shallow tillage to remove weeds), cover with single species (two treatments covered with different herbages), cover with mixed species (two combination treatments named M1 and M2 respectively), and cover with a crop on soil physicochemical properties and fungal community structure in a vineyard in northern China in 2020 and 2021. Soil total carbon and mineral nitrogen increased under Carex lanceolata Boott, Medicago sativa L., M1, and M2 covers but decreased under Glycine max (L.) Merr. Compare to traditional management. Soil organic carbon content increased under Carex lanceolata Boott, Medicago sativa L., M1, and M2, with increasing planting time. Cover cropping management had a minor effect on fungal diversity in the short term. Effects on beneficial and pathogenic fungi varied with cover type. With a cover of Glycine max (L.) Merr, the abundance of Fusarium brachygibbosum , a pathogen that affects grape production, increased, but that of Chaetomium , a genus that inhibits pathogens, also increased. With a cover of Carex lanceolata Boott, the abundance of Didymella glomerata , another pathogen that affects grape production, increased, but that of Metarhizium , an entomopathogenic fungus, also increased. Compared with Carex lanceolata Boott, covers with mixed species (M1 and M2) showed minor effects on soil pathogens, so covers with mixed species could benefit the vineyards more than other cover cropping management in North China. • Cover cropping management can improve soil carbon and nitrogen in vineyard. • Cover cropping management has impacts on grape productivity-related fungi. • SOC is the major drivers of fungal diversity and Didymella glomerata. [ABSTRACT FROM AUTHOR]