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以棕壤为供试土壤,研究了烤烟不同种植方式(绿肥烤烟轮作、烤烟纯作、麦茬烟和麦套烟)对烟田耕层土壤酶活性的影响。结果表明,在研究时段内,耕层土壤(0～25 cm)的过氧化氢酶、蔗糖酶和脲酶活性在4种种植方式下均无显著差异,但3种土壤酶活性随时间的变化各异,其中过氧化氢酶随时间变化较平稳,在烤烟移栽后30 d(6月20日)有最低值;蔗糖酶活性在烤烟移栽30 d后有所下降,随后逐渐升高,在采收期(9月7日)达到最高值;脲酶活性在烤烟现蕾期(移栽后68 d)达到最高值,随后急剧降低。就不同土壤层次(0～5 cm,5～15 cm,15～25 cm)而言,烟田土壤过氧化氢酶和脲酶活性在耕层内随土壤深度增加而增加,但增幅较小;而蔗糖酶活性在耕层内随土层深度大致呈现先增加后减小的趋势。在整个烤烟生育期内土壤酶活性的时间变异表现为,土壤脲酶的时间变异系数最大,显示其受外界环境的影响最大;蔗糖酶次之,而过氧化氢酶最小,其季节变化最稳定。
Using brown soil as tested soil, the effects of different cultivation methods of flue-cured tobacco (rotation of green manure flue-cured tobacco, pure flue-cured tobacco, wheat stubble tobacco and wheat straw tobacco) on soil enzyme activities in tobacco field were studied. The results showed that there was no significant difference in catalase, invertase and urease activities in topsoil (0 ~ 25 cm) under the four cultivation methods during the study period, but the activities of three kinds of soil enzymes varied with time The catalase activity changed steadily with time and had the lowest value at 30 days after transplanting (June 20). The activity of sucrase decreased after 30 days of transplanting and then increased gradually Harvest time (September 7) reached the highest value; urease activity in the budding stage of flue-cured tobacco (68 d after transplanting) reached the highest value, then decreased sharply. In different soil layers (0 ~ 5 cm, 5 ~ 15 cm, 15 ~ 25 cm), catalase and urease activities in tobacco soil increased with increasing soil depth in the topsoil, but with a small increase; Sucrase activity in the topsoil with the soil depth roughly showed the first increase and then decrease. The time variation of soil enzyme activity during the whole growth period of flue-cured tobacco showed that the maximum coefficient of variation of soil urease was the highest under the influence of the external environment; the sucrase was the second, and the catalase was the smallest, the seasonal variation was the most stable.