School of Environment, Beijing Normal University, 100875, China.
J Environ Manage. 2013 Oct 15;128:393-9. doi: 10.1016/j.jenvman.2013.05.058. Epub 2013 Jun 19.
Quantifying the carbon storage of grasslands under different management strategies can help us understand how this ecosystem responds to different land management practices. To assess the C cycle and the importance of soil microbial biomass carbon, we measured the levels of soil organic carbon, biomass carbon (above- and underground) and soil microbial biomass carbon in areas with different grazing intensities and different management strategy (fenced and unfenced) in the Qinghai-Tibetan Plateau. We also calculated the ratio of soil microbial biomass carbon to soil organic carbon as an indicator of the soil organic matter availability and quality. Results showed that degradation had significant effects on the soil organic carbon, biomass carbon and microbial biomass carbon (P < 0.05). However, fencing only had a significant effect on the non-degraded and moderately degraded grasslands (P < 0.05). We also found that the level of soil microbial biomass carbon was positively correlated with the biomass carbon and soil organic carbon. From our research, we concluded that the level of soil microbial biomass carbon was crucial to the C cycle in the alpine grasslands and that fencing may be an important management strategy for restoring lightly or moderately degraded grassland in the Qinghai-Tibetan Plateau.
量化不同管理策略下草原的碳储存量可以帮助我们了解这个生态系统对不同土地管理实践的响应。为了评估 C 循环和土壤微生物生物量碳的重要性，我们测量了青藏高原不同放牧强度和不同管理策略（围栏和无围栏）下的土壤有机碳、生物量碳（地上和地下）和土壤微生物生物量碳的水平。我们还计算了土壤微生物生物量碳与土壤有机碳的比值，作为土壤有机质可用性和质量的指标。结果表明，退化对土壤有机碳、生物量碳和微生物生物量碳有显著影响（P < 0.05）。然而，围栏只对未退化和中度退化的草地有显著影响（P < 0.05）。我们还发现，土壤微生物生物量碳的水平与生物量碳和土壤有机碳呈正相关。从我们的研究中，我们得出结论，土壤微生物生物量碳的水平对高寒草地的 C 循环至关重要，围栏可能是恢复青藏高原轻度或中度退化草地的重要管理策略。
