Different effects of identical mowing pattern on plant community and soil microbe of meadow steppe in different land use backgrounds in Inner Mongolia, China

Abstract:

The appropriate mowing pattern is necessary to be investigated for ensuring the maximum extent feeding supply to livestock and avoiding grassland degradation simultaneously. Previous research about mowing pattern mostly focused on the impact of different cutting ways, such as cutting height, frequency and times, but the land use background factor was commonly ignored. For this reason, we conducted an identical mowing interval gradients experiment (mowing in every 1, 2 and 3 years) in two plots under different land use backgrounds from 2005. One plot was mowed (MP) in every year dominant by Leymus chinensis(Trin.) Tzvel. and the other plot was grazed (GP) before experiment conducted which is dominant by Stipa Baicalensis Roshev. Our results indicate that GP has significant advantages on species diversity, biomass and root-shoot ratio than that in MP under the same mowing interval pattern. Conversely, content of soil organic matter (SOM) and nutrient (total nitrogen, TN and total phosphorus, TP) in MP is significant greater than that in GP. Moreover, in terms of the amount of soil microflora, ammonifier abounded in MP, but anaerobic azotobacteria abounded in GP instead, which may confirm the higher content of TN in MP soil. In summary, the impact of identical mowing interval pattern on vegetation and soil performed diversely in MP and GP suggesting that land use background factor should be taken into account when a mowing pattern is made by government. Further work will be conducted to identify the different nutrient allocation patterns in each components on both individual and community scales which will help us to better understand the mechanisms of land use changing in semi-arid grassland ecosystem.