不同利用方式下山地土壤酶活性对有机物输入的响应

Effects of organic matter input on enzyme activities in mountain soil under different land use patterns

以不同土地利用方式(天然林、次生林、人工林和园地)下山地土壤为研究对象,通过室内培养试验,研究改变有机物输入对土壤酶活性的影响。结果表明,有机物输入后,不同土地利用方式下土壤脲酶、多酚氧化酶活性均显著低于对照,且随着输入量的增加其降幅减小;细柄阿丁枫天然林、米槠次生林和杉木人工林的土壤蔗糖酶活性则随着有机物残体数量的增加而增加,均显著高于对照。加入不同种类有机残体时,蔗糖酶和脲酶活性均表现出叶残体>根残体的趋势,而多酚氧化酶活性与之相反。蔗糖酶活性随着培养时间的延长而降低,降幅15.5%-51.5%,而脲酶和多酚氧化酶活性却随之升高。多酚氧化酶活性随着温度的升高而增加,增幅高达97.6%,蔗糖酶活性则是随温度升高而不断下降,在10-20℃时脲酶活性较高;土壤酶活性随湿度的增加而增加,当湿度超过60%时,土壤酶活性反而下降,说明湿度60%是土壤酶较适宜的湿度。

In order to assess the effects of organic matter input on soil enzyme activities under different land use patterns （ natural forest, secondary forests, plantation and orchard）, the soil samples were investigated in Jian＇ou City, Fujian Province, China. The results showed that when inputting organic matter, the activities of urease and polyphend oxidase in different land use patterns were lower than the control, but the decreasing range reduced with continuing input. With the increase of the residual quantity, the activity of invertase significantly increased, in addition to orchard, and was higer than the control. When inputting different quality residual, the activities of urease and invertase showed leaf 〉 root, and the polyphend oxidase on the contrary. With longer incubation time, the activities of invertase had a downward trend from 15.5% to 51.5%, the urease and polyphend oxidase increased. With the increase of temperature, the activities of polyphend oxidase increased up to 97.6%, invertase decreased, and urease had a higher activity between 10 ℃ and 20 ℃. Besides, 60% of soil moisture was beneficial for soil enzyme activity.