论文部分内容阅读
运用网袋法,在福建建瓯万木林自然保护区米槠天然林内,将米槠根系按直径大小分成0～1、1～2和2～4mm3个级别进行分解研究.结果表明:在为期2年(720d)的分解试验过程中,网袋内所有米槠根系的分解速率均呈现前期较快、后期较慢的变化特征,主要是可萃取物的淋溶损失使根系的前期分解较快,而酸不溶性物质浓度的上升抑制了其后期分解.根系分解1年(360d)后,不同径级根系的分解速率由其初始可萃取物和N浓度控制;而分解2年(720d)后,其根系底物中初始C/N、初始酸不溶物质与N、P浓度共同决定分解速率.在分解过程中,米槠3个径级根系都表现为N浓度不断上升、P浓度不断下降的趋势,其中N的释放呈现富集-释放格局,而P则为直接释放.
The net bag method was used to decompose the root system of rice bran into 0 ~ 1, 1 ~ 2 and 2 ~ 4mm3 according to the diameter in Fujian Mianmulin Nature Reserve in Jianou County, Fujian Province.The results showed that in the period of 2 During the decomposition experiment of 720 days, the decomposing rates of all rice bran roots in the net bag showed the characteristics of rapid and late changes in the early stage, mainly due to the leaching loss of extractables, However, the increase of acid-insoluble material inhibited its decomposition in the later stage.The decomposition rate of root system with different diameter was controlled by its initial extractables and N concentration after one year of root decomposition (360 days) The initial C / N, the initial acid-insoluble matter and the concentration of N and P in the root substrate determine the decomposition rate.During the decomposition process, the root system of three diameter grades showed the increasing trend of N concentration and P concentration, Among them, N release showed enrichment-release pattern, while P was direct release.