Effects of Different Intensity Thinning on Litter Decomposition in Chinese Fir Plantations
In order to understand the response of litter decomposition on thinning intensity, we study the dynamic changes of litter decomposition rate and chemical composition, and analyze their relationships with a part of environmental factors in a Chinese fir plantation in Lishui District, Nanjing. The purpose is to lay the foundation for the study of different thinning intensities on litter decomposition mechanism characteristics, and provide scientific basis for the sustainable development of artificial coniferous forests. The results are as follows: (1) Litter decomposition rate has been significantly affected by thinning. Compare with control check, litter decomposes fastest in medium-intensity-thinning (mass loss: 31.98%) and faster in light-intensity-thinning (mass loss: 30.94%), but it shows a decrease in high intensity thinning (mass loss: 27.03%). (2) During one year decomposition,it has showed a net accumulation ofw(N) and similar trends ofw(C)/w(N) andw(lignin)/w(N) in all plots. Among them, medium intensity thinning has a significantly influence on nitrogen content. In addition,w(C)/w(N) is an ideal indicator to reflect litter decomposition rates. (3) Through change the temperature and activities of cellulase and invertase in litter layer, thinning can influence litter decomposition rate. Our results suggest that moderate thinning can change the litter layer temperature and enzyme activities, accelerating the decomposition of litter in a Chinese fir plantation, thus, reduce excessive litter accumulation, improving soil nutrient input. However, excessive thinning will inhibit the litter decomposition, nutrient utilization and return block. This study is meaningful of further exploring the mechanism of material and nutrients’ cycle affected by thinning. It can provide some scientific basis for developing reasonable and effective measures to promote the forest, promoting conifer plantation nutrient cycle.
Chinese fir plantationthinning intensitieslitterchemical compositiondecomposition rate
国家科技期刊平台
NSTL
万方数据
维普
