草地盐碱化对灰绿碱蓬生物量及其土壤酶活性的影响

Effect of Grassland Salinization on Suaeda glauca Biomass and Soil Enzymes Activity

目的探讨草地盐碱化对碱蓬生物量及其土壤酶活性的影响。方法选取3个盐碱化程度不同的人工种植碱蓬样地,测定生长的碱蓬生物量及进行土壤淀粉酶活性、脲酶活性、多酚氧化酶活性的测定。结果在土壤可溶性盐含量达0.59%的盐碱化草地上人工种植灰绿碱蓬生长良好,其地上部分生物量达738.7g.m-2。当土壤可溶性盐含量达0.73%时对灰绿碱蓬生长产生明显的抑制效应,其地上部分生物量只有83.4g.m-2,降幅达88.71%。然而,当土壤可溶性盐含量增至1.14%时地上生物量降幅却不是很大,较土壤可溶性盐含量0.73%时下降只有29.8%。随着盐碱化程度加深,生物量显著降低,淀粉酶、脲酶活性受到抑制,多酚氧化酶活性有提高。结论土壤淀粉酶活性与灰绿碱蓬地上部分生物量和土壤有机质含量间呈极显著正相关(P<0.01)、而与土壤可溶性盐含量和土壤pH间呈极显著负相关(P<0.01);土壤脲酶活性与灰绿碱蓬地上部分生物量和土壤有机质含量间分别呈极显著正相关(P<0.01)和显著正相关(P<0.05),而与土壤pH呈极显著负相关(P<0.01),与土壤可溶性盐含量间相关性不显著;土壤多酚氧化酶活性与可溶性盐含量呈极显著相关(P<0.01),与其它指标相关性不显著。

Objective This paper explored the effect of the grassland salinization on Suaeda glauca Biomass and soil enzyme activity.Methods Select three artificial planting saline alkali soil with different salinization degrees,and measured the Suaeda salsa biomass,then determined the value of the soil amylases of urease activity and polyphenol oxidase amylase activity.Results The artifical cultivated Suaeda glauca grew well in the soil with the soluble content 0.59%,and the biomass in aboveground part reached 738.7g·m-2.While there were apparent inhibitory effect when the soluble content of the soil reached 0.73%,the decreasing amplitude of biomass in aboveground part reache 88.71% with the value of 83.4g·m-2.However,when the soluble content of the soil increased to 1.14%,the biomass in aboveground part decrease only by 29.8% compared with a soil soluble content 0.73%,which meant the decreasing amplitude of the biomass were not so obvious.That is,with the deepening of the alinization degree,the biomass reduced dramatically and the amylase activity and urease activity were also restrained,while the polyphenol oxidase activity was increased.Conclusion There has significantly positive correlation（P0.01） between the soil amylase activities and the overground biomass of Suaeda glauca and organic content of soil,but there has significantly negative correlation（P0.01） between the soil amylase activities and the soluble salt content of soil and soil pH.The urease activity of soil keeps significantly positive correlation（P0.05） and significant positive correlation（P0.01） respectively with the overground biomass of Suaeda salsa and the organic content of soil,yet there is significantly negative correlation（P0.01） between the urease activity of soil and the soil pH,and there has no significant correlation between the urease activity of soil and the soluble salt content of soil;There has significant correlation（P0.01） between polyphenol oxidase activity of soil and soluble salt content of soil,however,the polyphenol oxidase activity of soil has no significant correlation with others.