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控制火烧是火炬松(Pinus taeda)生态系统的一项普通的经营措施。一些研究已经验明氮素的挥发损失,但对氮素的持续有效性的适用资料很少。我们验明了在火炬松成熟林中控制弱度火烧的效应,发现林地层的氮含量没有显著减少,而林地层的分解率为火烧后第一生长季的1倍多。这种分解释放的氮为60kg/ha,超过没有火烧的相同林分。用叶子分析和土壤保温亦表明了增氮的有效性。这种有效氮的波动也许是松树生长的肥料效应,而且可以代替轮伐期末施氮肥。
Controlling the burning of fire is a common management measure of the Pinus taeda ecosystem. Some studies have demonstrated the volatilization of nitrogen but little information is available on the continued availability of nitrogen. We identified the effect of controlling the weakness of fire in the Pinus taeda mature forest and found no significant reduction in nitrogen content in the forestland, whereas the decomposition rate in the forestland was more than double that in the first growing season after fire. The nitrogen released by this decomposition is 60 kg / ha, exceeding the same stand without fire. Leaf analysis and soil insulation also showed the effectiveness of increasing nitrogen. Fluctuation of this available nitrogen may be a fertilizer effect of pine growth and may replace nitrogen fertilization at the end of the rotation.