森林土壤酚类物质的消解规律

Digestion of soil phenolic substances in forest ecosystem

采用室内模拟培养的研究方法,对4种森林生态系统(天然更新常绿阔叶林、一代杉木老龄林、二代杉木萌芽天然更新林、二代杉木人工林)土壤酚类物质含量的动态变化规律进行研究.结果表明,在常温或冷藏状态下,各系统土壤总酚、复合态酚和水溶性酚含量基本上呈现明显降低的趋势,各系统土壤总酚、复合态酚和水溶性酚的总消解率分别为64.91%-91.21%、58.13%-83.24%和65.27%-83.78%.在冷藏状态下,土壤总酚的消解率比在常温状态的土壤低,说明低温抑制了土壤总酚的消解作用,而对土壤复合态酚和水溶性酚的消解率影响不明显.不同森林生态系统的土壤总酚和复合态酚的消解率均存在显著差异,不同森林生态系统土壤水溶性酚的消解率差异不显著.初始酚类物质含量高的土壤系统,其消解率也较高,表明如果没有外来的酚类物质继续加入,土壤中各种酚类物质的消解率较高.由此推测,在野外自然条件下,酚类物质在土壤中发生严重积累并造成林木中毒的可能性较小.

By the method of indoor simulation culture,dynamics of soil phenols content of four forest ecosystems including naturally renewal evergreen broad-leaved forest,first-rotation old-growth forest of Chinese fir,second-rotation natural renewal sprout forest of Chinese fir,second-rotation plantation of Chinese fir have been investigated.The results showed that either at room temperature or under cold conditions,the content of soil total phenol,complex phenol and water soluble phenol tended to decrease,the total digestion rates of soil total phenol,complex phenol and water soluble phenol in the four systems were 64.91%-91.21%,58.13%-83.24% and 65.27%-83.78%.The digestion rate of soil total phenol in refrigeration was lower than that at room temperature,which indicated that hypothermia could inhibit the digestion rate of soil total phenol,and the effect of hypothermia on digestion rate of complex phenol and water soluble phenol was not obvious.Except the water soluble phenol,the digestion rates of soil total phenol and complex phenol significantly varied with different forest ecosystems.The higher was initial content of phenolic substances in soil system,the larger was the digestion rate of phenolic substances,which meant that if no exogenous phenolics to join,digestion rates of soil phenolic substances were higher.It was speculated that,in the field of natural conditions,large accumulation of phenolic substances causing forest poisoning in soil was less likely.