Decomposition of leaf litter of Chinese fir in response to increased nitrogen deposition
A field simulated experiment was conducted in a Chinese fir plantation in central western Fujian Province,to study the decomposition of leaf litter of Chinese fir in response to increased nitrogen deposition. Treatments were designed as NO (0 kg/(hm2·year)) ,N1(60 kg/(hm2·year)) ,N2 (120 kg/(hm2·year)) and N3 (240 kg/(hm2·year) ) , with three replicates in each treatment. After 660 days of leaf litter decomposition, the litter remaining rate was estimated to be 24.58% ,21.99% , 15.46% and 25.17% for N0,N1,N2,N3 treatments, respectively. Based on Olson equations,decomposition coefficient k for the above treatments was estimated to be 0.776 4,0.807 6,1.018 8 and 0.760 8, with 95% litter decomposition time of 3.99,3.95, 3.06,4.11 years, respectively, suggesting that the low-to-medium N loads (N1 and N2) increased the litter decomposition rate, but high levels of N deposition (N3) was found to inhibit the decomposition to some extent. The N concentrations of leaf litter increased with the increased nitrogen loads, leading to lower C/N ratios. Decomposition coefficient was observed to have positive linear relationship with N concentrations in leaf litter,but negative relationship with C/N ratios for the treatments except for N3.
Chinese fir plantationnitrogen depositionlitter decompositionC/N ratio
国家科技期刊平台
NSTL
万方数据
维普
