图1. 甘肃陇东覆膜苹果园亚表层土壤团聚体组成及稳定性(平均值±标准差)。A, 团聚体破坏率(PAD)。B, 水稳系数(WSC)。C, 水稳性团聚体平均质量直径(MWD)。D, 水稳性团聚体平均几何直径(GMD)。E, >0.25 mm机械稳定性团聚体含量(DR_0.25)。F, <0.25 mm水稳性团聚体含量(WR_0.25)。CK, 对照; 2Y, 覆膜2年; 4Y, 覆膜4年; 6Y, 覆膜6年。不同小写字母表示不同处理间各指标存在显著差异(p < 0.05)。

Fig. 1. Composition and stability of subsurface soil aggregates of film mulching apple orchard in Longdong, Gansu (mean ± SD). A, Agglomerate failure rate (PAD). B, Water stability coefficient (WSC). C, Average mass diameter of water-stable aggregates (MWD). D, Average geometric diameter of water-stable aggregates (GMD). E, >0.25 mm mechanical stability aggregate content (DR_0.25). F, <0.25 mm water-stable aggregate content (WR_0.25). CK, control treatment; 2Y, mulching for 2 years; 4Y, mulching for 4 years; 6Y, mulching for 6 years. Different lowercase letters indicate that there are significant differences (p < 0.05) in each index among different treatments.