降水量变化对藏北高寒草地养分限制的影响

宗宁, 石培礼, 赵广帅, 郑莉莉, 牛犇, 周天财, 侯阁

Variations of nitrogen and phosphorus limitation along the environmental gradient in alpine grasslands on the Northern Xizang Plateau

ZONG Ning, SHI Pei-Li, ZHAO Guang-Shuai, ZHENG Li-Li, NIU Ben, ZHOU Tian-Cai, HOU Ge

表2 以年份为重复因子, 利用重复测定方差分析氮磷添加对不同草地类型高寒草地植物功能群地上生产力的影响

Table 2 Using year as the repeated factor, Repeated Measure ANOVA analysis of the effects of nitrogen and phosphorus addition on the aboveground biomass of different types of alpine grasslands

功能群 Functional group 年份 Year 施肥 Fertilization 草地类型 Grassland 年份×施肥 Year × Fertilization 年份×草地 Year × Grassland 草地×施肥 Grassland × Fertilization 年份×草地×施肥 Year × Grassland × Fertilization df = 2 df = 3 df = 3 df = 6 df = 6 df = 9 df = 18 F p F p F p F p F p F p F p 群落 Community 14.81 <0.001 24.70 <0.001 336.91 <0.001 0.83 0.55 2.92 0.014 2.78 0.016 0.77 0.73 禾草 Grasses 16.98 <0.001 33.60 <0.001 30.68 <0.001 5.64 <0.001 12.59 <0.001 6.92 <0.001 4.19 <0.001 莎草 Sedges 2.63 0.080 3.82 0.019 403.75 <0.001 0.53 0.79 2.07 0.069 3.04 0.01 0.56 0.91 豆科 Legumes 11.57 <0.001 3.64 0.023 24.66 <0.001 0.92 0.48 11.34 <0.001 6.81 <0.001 1.29 0.48 杂类草 Forbs 6.49 0.003 7.38 0.001 52.69 <0.001 2.15 0.060 7.23 0.003 1.44 0.21 3.27 <0.001