地木耳（Nostoc commune）是一种固氮蓝藻，其固氮活性是可逆的，在天然草地氮素循环中起着重要的作用。试验模拟了年际间降水量变化和放牧强度对地木耳生长的影响，以期为合理利用和管理天然草地提供依据。结果表明，适度放牧促进了地木耳的生长，其早期和后期生长速度分别是不放牧时的3倍和4倍，不放牧时生长最慢。降水量对地木耳后期生长速度与早期生长速度的影响呈相反的趋势，高降水量显著提高了早期生长速度，是最低降水量时的14倍；平均降水量显著提高了后期生长速度。适度放牧、高降水量时早期生长速度最快，适度放牧、平均降水量时后期生长速度最快。%Nostoc commune is a nitrogen-fixing blue algae with reversibly characteristic and it plays an important role in the nitrogen cycle of the natural grassland. A simulation experiment was conducted to determine the effects of rainfall and grazing intensity on the growth rate of N. commune in this study. The results of this study indicated that moderate grazing benefited the growth of N. commune, and its growth rate was three times and four times at early and late growth stage of no-grazing, respectively, and the lowest N. commune growth rate was observed in the no-grazing treatment. Rainfall showed different effects on the early growth rate and the late growth rate of N. commune, indicating that the high rainfall significantly increased the early growth rate, and the early growth rate in high-rainfall treatment was fourteen times that of low rainfall, and moderate-rainfall significantly increased the late growth rate. The highest early growth rate of N. commune was presented in the treatment with moderate grazing and high-rainfall and the highest late growth rate of N. commune was presented in the treatment with moderate grazing and average-rainfall.
展开▼
