TN in the soil layers above and below the straw layer was significantly influenced by the amount of wheat straw (P < 0.05) (Fig. 1a–c). For TN above the straw layer, it was only increased by
TN in the soil layers above and below the straw layer wassignificantly influenced by the amount of wheat straw (P < 0.05)(Fig. 1a–c). For TN above the straw layer, it was only increased by