Ying Yong Sheng Tai Xue Bao. 2016 May;27(5):1368-1374. doi: 10.13287/j.1001-9332.201605.004.
In order to detect the effects of simulated nitrogen deposition on litter decomposition and degradation of lignin and cellulose, a one-year field experiment of simulated nitrogen deposition has been conducted using litter bag method from November 2013 to November 2014 in an evergreen broad-leaved forest, Rainy Area of West China. Four levels of nitrogen deposition were set, i.e., control (0 g N·m·a), low (5 g N·m·a), medium (15 g N·m·a) and high (30 g N·m·a) nitrogen deposition. The results indicated that foliar litter decomposed faster in summer, obviously faster than in the other seasons. N deposition significantly inhibited the decomposition of foliar litter in this evergreen broad-leaved forest. As N deposition increased, the inhibition effect was enhanced. The time of 95% mass loss (T) of foliar litter due to simulated N deposition was increased by 0.53-1.88 years compared with T of control (4.81 years). N deposition significantly inhibited the degradation of lignin and cellulose. The mass remaining after one year of decomposition of lignin and cellulose in the medium and high nitrogen deposition treatments were significantly higher than that in the control. There was a significant positive linear relationship among mass remaining rate and lignin and cellulose remaining rates. The inhibiting effects of inorga-nic N on degradation of lignin and cellulose explained the inhibitory effect of N on foliar litter decomposition.
为了探究模拟氮沉降对凋落物分解以及木质素和纤维素降解的影响，于2013年11月至2014年11月在中国西部多雨区的常绿阔叶林，采用凋落物袋法进行了为期一年的模拟氮沉降田间试验。设置了四个氮沉降水平，即对照（0 g N·m⁻²·a⁻¹）、低氮（5 g N·m⁻²·a⁻¹）、中氮（15 g N·m⁻²·a⁻¹）和高氮（30 g N·m⁻²·a⁻¹）沉降。结果表明，叶凋落物在夏季分解更快，明显快于其他季节。氮沉降显著抑制了该常绿阔叶林中叶凋落物的分解。随着氮沉降增加，抑制作用增强。与对照的95%质量损失时间（T，4.81年）相比，模拟氮沉降导致叶凋落物的95%质量损失时间增加了0.53 - 1.88年。氮沉降显著抑制了木质素和纤维素的降解。中氮和高氮沉降处理下木质素和纤维素分解一年后的剩余质量显著高于对照。剩余质量率与木质素和纤维素剩余率之间存在显著的正线性关系。无机氮对木质素和纤维素降解的抑制作用解释了氮对叶凋落物分解的抑制作用。
