WITHDRAWN: Heavy Grazing Reduces the Diversity of Soil Microbial Communities in Meadow Grassland Under Long-Term Grazing

Abstract Background: Soil microorganisms are an important part of the grassland ecosystem and promote material transformation and energy flow in the entire ecological environment. Moreover, Hulun Buir grassland is the material basis for the development of animal husbandry. Therefore, it is of great scientific significance to study the changes of soil microbial community caused by grazing in Hulunbuir grassland for the sustainable and stable development of grassland ecosystem. Methods: The present research used high-throughput sequencing of soil microorganism (bacteria and fungi) genes to compare microbial communities in 6 levels of grazing intensity (0.00, 0.23, 0.34, 0.46, 0.69, and 0.92 Au ha -1 ) under the Hulun Buir structure and the diversity characteristics of Leymus chinensis meadow steppe. Results: The 0-10 cm soil layer of the G0.34 test area had the highest content, and the content of the G0.92 test area was lower than the other grazing treatments. With increasing depth, the carbon and nitrogen contents of microorganisms decreased. The diversity of soil bacteria in the light grazing test area (0.23Au ha -1 ) was higher than the heavy grazing area, and the diversity of fungi in the non-grazing area was higher than the specific grazing areas. Most bacterial species were enriched in the G0.00 grazing areas, and the other grazing intensities were less abundant. The underground biomass (P = 0.039) significantly influenced the bacterial community structure, and pH (P =0.032), total nitrogen (P =0.011) and litter (P =0.007) significantly influenced the fungal community. Conclusions: In conclusion, the structures of bacterial and fungal communities are very sensitive to grazing and varied with grazing intensity. Our findings demonstrated that a grazing intensity of approximately 0.23 Au ha -1 was the most appropriate for the grassland of the meadow in Hulun Buir.