Abstract: As one of the effective grassland management strategies, mowing has significant effects on ecosystem function and diversity. Taking Stipa grandis steppe of Xilin Gol, Inner Mongolia as object, and fencing grassland as reference, we studied the effects of different mowing stubble heights (residue heights of 8 cm, 5 cm and 2 cm) on community biomass and diversity. The results showed that compared with fencing grassland, residue 8 cm has no significant effects on above-ground biomass, whereas, residue heights of 5 cm and 2 cm significantly reduced above-ground biomass (P<0.05);at function group and species levels, perennial bunchgrass and the biomass of S. grandis were significant decreased by residue 2 cm (P<0.05);residue heights of 8 cm and 5 cm increased community species diversity index (P<0.05). The results showed that reasonable stubble height has a positive impact on grassland species diversity and aboveground biomass, which is of great significance for guiding local production and improving the rational utilization of grassland.

Key words: Mowing stubble height, Stipa grandis steppe, Species diversity, Aboveground biomass

摘要： 刈割作为草地有效管理手段之一，对生态系统功能与多样性均具有重要的影响。本研究以内蒙古锡林郭勒盟大针茅草原为研究对象，利用围封草地作为对照，探讨了不同刈割留茬高度（留茬8 cm、留茬5 cm和留茬2 cm）对群落生物量与多样性的影响。结果表明：与围封草地相比，留茬8 cm对地上生物量无显著影响，留茬5 cm和2 cm处理显著降低了群落地上生物量（P<0.05）；多年生禾草和大针茅生物量在留茬2 cm处理下显著降低（P<0.05）；留茬8 cm和5 cm处理显著提高了群落物种多样性指数（P<0.05）。相关结果表明合理的留茬高度对草原物种多样性和地上生物量有积极影响，本试验对指导当地生产实际、提高草地合理利用等方面具有重要意义。

关键词: 刈割留茬高度, 大针茅草原, 物种多样性, 地上生物量