图1. 中性糖在不同土地利用类型表层土壤中的含量和来源(Nierop et al., 2001; Spielvogel et al., 2007; Eder et al., 2010; Rumpel et al., 2010; Zhao et al., 2014; Conti et al., 2016; Cui et al., 2016; Wang et al., 2016; Creme et al., 2017; Llorente et al., 2017; Evgrafova et al., 2018; Zhu et al., 2018)。A, 中性糖绝对含量。B, 中性糖相对含量。C, GM/AX ((半乳糖+甘露糖)/(阿拉伯糖+木糖))。D, RF/AX ((鼠李糖+岩藻糖)/(阿拉伯糖+木糖))。箱式图上方和下方的线段分别表示上四分位数和下四分位数,箱式图内部的横线表示数据的中位数,箱式图中在最上方或最下方的圆圈表示样本数据中的极端值。不同小写字母表示不同土地利用类型间差异显著(p < 0.05)。A, C, 阔叶林n = 8, 针叶林n = 25, 灌丛n = 4, 草地n = 8, 耕地n = 15。B, 阔叶林n = 8, 针叶林n = 22, 灌丛n = 4, 草地n = 8, 耕地n = 15。D, 阔叶林n = 3, 针叶林n = 19, 灌丛n = 4, 草地n = 8, 耕地n = 27。OC, 土壤有机碳。

Fig. 1. Content and distribution of neutral sugars across different land-use regimes in the top soils (Nierop et al., 2001; Spielvogel et al., 2007; Eder et al., 2010; Rumpel et al., 2010; Zhao et al., 2014; Conti et al., 2016; Cui et al., 2016; Wang et al., 2016; Creme et al., 2017; Llorente et al., 2017; Evgrafova et al., 2018; Zhu et al., 2018). A, Neutral sugar absolute content. B, Neutral sugar relative content. C, GM/AX ((galactose + mannose)/(arabinose + xylose)). D, RF/AX ((rhamnose + fucose)/(arabinose + xylose)). The upper and lower end of boxes denote the 0.25 and 0.75 percentiles, respectively. The solid bar in the box mark the median of each dataset. The circles indicate outliers of each dataset. Different lowercase letters indicate differences in various land-use regimes (p < 0.05). n = 8, 25, 4, 8, 15 (from deciduous, coniferous, shrub, grassland to crops in the A, C). n = 8, 22, 4, 8, 15 (from deciduous, coniferous, shrub, grassland to crops in the B). n = 3, 19, 4, 8, 27 (from deciduous, coniferous, shrub, grassland to crops in the D). OC, soil organic carbon.