不同形态外源N对木荷马尾松叶凋落物分解的影响

The Effect of Different Form Nitrogen Addition on Decomposition of Schima superba and Pinus massoniana Leaf Litter

将中亚热带木荷马尾松叶凋落物置于不同形态外源N下进行模拟分解实验,研究结果表明:NH4Cl和NaNO3溶液均能有效提高木荷叶的分解速率,而且加入的量越多其分解速度越快。但与等量的水相比,只有当溶液量增到300ml时,外源铵态氮和硝态氮对其分解的促进作用才明显超过水的影响,达到极显著水平。NH4Cl和NaNO3溶液在一定程度上也都能促进马尾松叶的分解,但不同处理间对其影响的差别不大,外源铵态氮对马尾松落叶分解速率的影响不如等量水的强,与水相比,在三种处理中,只有加200mlNaNO3溶液时能显著提高马尾松落叶的分解速率。总体上外源氮对马尾松叶分解的影响不如对木荷落叶的明显。

The effect of different form nitrogen addition on decomposition of Schima superba and Pinus massoniana leaf litter from mid-subtropical zone were studied using a self-designed lysimeter. The results showed that： decomposition rates would all be obviously accelerated by NH4Cl and NaNO3 adding, and added more NH4^＋ -N and NO3^- -N liquor, S. superba leaves decompose more quickly. But compared with the effects of same quantity of distilled water, the accelerating effects of NH4^＋ -N and NO3^- -N could very significantly appear till added 300 ml liquor. To some extend the decomposition rates of P. massoniana needles also would be accelerated by adding NH4Cl and NaNO3, but compared with CK the effects of a certain quantities of distilled water were stronger than NH4^＋ -N and NO3^- -N, and in the three treatments only when add 200 ml NaNO3 liquor could more obviously accelerated P. massoniana needles decomposition rates than distilled water. On the whole the effects of addition N on P. massoniana needles decompose were not as stronger as on S. superba leaves.