摘要
通过研究外源性氮和磷对尾叶桉(Eucalyptus urophylla)凋落叶分解速率、分解过程中N、P含量变化的影响,为森林养分管理提供科学依据。采用尼龙网袋分解法,在广东的尾叶桉林内建立4块5 m×5 m的小样地,放置凋落叶样品,测定其分解速率和N、P含量变化。结果表明,外源性N在试验前期分解速率有促进作用,后期阻碍了凋落叶分解。24个月时对照、施N、P和N+P的凋落叶残留量分别为初始重量的0.23%、1.59%、0.19%和0.49%。凋落叶分解24个月时尾叶桉林地各处理的凋落叶N、P含量均大于初始值,对照、施N、P和N+P的凋落叶N的残留量分别为初始N重量的0.54%、2.41%、0.35%和0.81%,凋落叶P的残留量分别为初始P重量的0.48%、1.74%、0.56%和1.52%,表明4种处理的凋落叶N和P均为释放模式。施N抑制尾叶桉凋落叶的分解,而施P及N+P促进其凋落物的分解,表明施用P肥可以促进尾叶桉凋落叶的分解和养分循环。
The effects of extemal nitrogen and phosphorus on leaf litter decomposition in a Eucalyptus urophylla woodland were studied for providing a scientific basis for E. urophylla nutrient management. The study was conducted over 2 years using the litterbag technique in Yongyun Forest Farm, Guangdong Province, China. Four small sample plots （5 m x5 m） were established in the investigated stand. Within each of the sample plots, leaf litters were placed and their decomposition rates and N, P and K contents were analyzed. The results showed that addition of N improved litter decomposition in the early stage and impeded litter decomposition in the late stage of the experiment. After twenty-four months of decomposition, the remaining weight of leaf litter was 0.23%, 1.59%, 0.19% and 0.49% of the initial weight of leaf litter in CK, N addition, P addition and N＋P addition treat- ments, respectively. After twenty-four months of decomposition, the N and P contents in leaf litter were greater than their initial values, and the remaining N weight of leaf litter was 0.54%, 2.41%, 0.35% and 0.81% of the ini- tial N weight in four treatments, respectively. The remaining P weight of leaf litter was 0.48%, 1.74%, 0.56% and 1.52% of the initial P weight in CK, N addition, P addition and N＋P addition treatments, respectively, indicating that N and P release patterns exist in decomposing leaf litter. In a word, N addition delays decomposition of leaf litter, whereas addition of P or N＋P accelerates its decomposition; therefore application of P fertilization can im- prove litter decomposition and nutrient cycling.
出处
《安徽农业大学学报》
CAS
CSCD
北大核心
2017年第3期409-414,共6页
Journal of Anhui Agricultural University
基金
中央财政林业科技推广示范项目"广东省生态公益林培育技术推广"(2015-GDTK-07)资助
关键词
尾叶桉
分解
凋落叶
外源性N和P
养分释放
Eucalyptus urophylla
decomposition
leaf litter
N and P additions
nutrient release
