氮肥添加对川西北高寒草甸植物群落根系动态的影响

字洪标,陈焱,胡雷,王长庭

Effects of nitrogen addition on root dynamics in an alpine meadow, Northwestern Sichuan

Hong-Biao ZI,Yan CHEN,Lei HU,Chang-Ting WANG

表2 不同N添加梯度根系动态的重复测量方差分析(n = 6)

Table 2 Repeated-measure variance analysis on the dynamic of plant roots of the different N addition fertilizer gradients (n = 6)

土层 Soil layer 根系指标 Root index 取样时间 Sampling time N添加梯度 N addition gradient 取样时间×N添加梯度 Sampling time × N addition gradient F p F p F p 0-10 cm 根系现存量 Root standing crop 81.262 < 0.001 7.468 0.010 1.579 0.239 根系生产量 Root production 63.809 < 0.001 1.078 0.412 9.53 < 0.001 根系死亡量 Root mortality 131.752 < 0.001 4.477 0.04 9.693 0.001 10-20 cm 根系现存量 Root standing crop 104.472 < 0.001 7.793 0.009 3.918 0.250 根系生产量 Root production 60.200 < 0.001 3.460 0.071 12.932 < 0.001 根系死亡量 Root mortality 138.540 < 0.001 0.482 0.704 14.224 < 0.001