Management practices amplify the effects of N deposition on leaf litter decomposition of the Moso bamboo forest

Abstract

The litter decomposition effects of N deposition in combination with management practices are still unclear. The aims of this study were to test the individual and interactive effects of the two factors on Moso bamboo leaf litter decomposition. The experiment was conducted in Moso bamboo forests over a 24-month period and included three N addition treatments (low N, 30 kg N ha−1 yr−1;medium N, 60 kg N ha−1 yr−1; and high N, 90 kg N ha−1 yr−1) and two management practices (conventional management and intensive management). The low-N treatment significantly increased the annual decomposition rate, whereas the high-N treatment significantly decreased the annual decomposition rate (P < 0.05). Intensive management alone did not significantly influence decomposition, but it amplified both the positive effects of the low-N treatment and the negative effects of the high-N treatment on litter decomposition. Intensive management weakened the positive effects of N addition on N loss but enhanced the positive effects on P loss during the early stage. The effects of increasing N deposition in a plantation ecosystem were altered by the management practices, and these changes should be considered when estimating the biological effects of N deposition at regional and global scales.