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在我国亚热带毛竹(Phyllostachys pubescens)主要产区的四片试验地上,随机布置了21个区组90个集叶斗,持续观察3a,以研究林内叶凋落物的动态。在相同立地上,又用同样方法布置20个区组400个落叶分解袋,通过林地潜育定期采集潜育样和样袋中残留物养分含量分析等方法,研究凋落物分解时的失重速率和N、P、K、Ca、Mg等养分元素的反馈。试验结果表明,毛竹林叶凋落物量在其年变化周期中有两个高峰期,峰值的出现时间由于立地条件的不同迟早不一。第一高峰值所代表的叶凋落物量因林分的生长特性不同其占全年总量的百分数变动于17—56％之间。竹叶凋落物在分解时其失重速率在初始期变化较快,但经20周林地潜育后渐趋稳定;养分的反馈情况因元素的不同而异,一些大量元素在其向土壤释放前于凋落物分解后的残留物中先有一个累积阶段。
In the four experimental plots in the main producing area of Phyllostachys pubescens in our country, 90 leaf bundles of 21 groups were randomly arranged and observed continuously for 3 years to study the dynamics of leaf litter in the forest. On the same site, 400 deciduous decomposition bags were set up in the same way in 20 plots. Through the methods of regularly collecting the latent samples and analyzing the nutrient contents in the sample bags, the rate of weight loss during litter decomposition and N, P, K, Ca, Mg and other nutrients feedback. The results showed that there were two peaks in the annual variation period of leaf litter in Phyllostachys pubescens forest, and the appearance time of the peak appeared different due to different site conditions. The amount of leaf litter represented by the first peak value varies from 17% to 56% due to the different growth characteristics of the stands. The rate of weight loss of bamboo litter changed rapidly during the initial period, but stabilized after it was submerged for 20 weeks. Nutrient feedback varied from element to element, There is an accumulation phase in the litter decomposition residue first.