外源性氮和磷对杉木林凋落叶分解的影响

Effect of N and P Additions on Decomposition of Leaf Litter in a Cunninghamia lanceolata Plantation

研究华南地区杉木人工林凋落叶分解对外源性N和P的响应,可为杉木林经营管理的养分管理提供参考。结果表明:施N对凋落叶分解有抑制作用,施P的凋落叶分解速率最快,施N+P也加快凋落叶分解。处理24个月后,施N处理的凋落叶N含量显著大于其初始含量,施P及N+P的N含量显著小于其初始含量;所有处理的凋落叶P含量显著大于其初始含量;凋落叶K在分解过程中呈现淋溶—富集—释放模式。

Leaf litter decomposition with N and P additions were studied in a Cunninghamia lanceolata planta- tion in South China, it could provided reference for nutrient management of C. lanceolata plantation management. The finding indicated that decomposition rate of leaf litter of C. lanceolata was postponed by N addition, that with P addition was the fastest among all treatments and N ＋ P addition treatment also accelerated leaf litter decomposition. Twenty-four months after the decomposition, the N content of leaf litter with N addition greater than its initial N content, whereas that with P and N ＋ P additions was significantly smaller than their initial N content. The P con- tent of leaf litter in all treatments was significantly greater than their initial P content. The K content of leaf litter displayed a pattern of leaching-enrichment-release.