长白楤木土壤酶活性及微生物量碳、氮特征对种植年限的响应

Response of Soil Enzymes Activities and Microbial Biomass Carbon and Nitrogen Characteristics to Planting Years of Aralia elata

本试验以连续种植2、5年和10年的长白楤木土壤(0~30 cm)为材料,研究土壤酶活性及土壤微生物量碳、氮的年际变化特征及相关性,以期为长白楤木的生长发育和栽培管理提供参考依据。结果表明,不同种植年限对长白楤木土壤酶活性影响显著,土壤脲酶、磷酸酶活性均表现为随着种植年限的延长呈逐渐下降趋势,而蔗糖酶活性变化趋势则相反;三种土壤酶活性总体表现为表层土壤显著高于深层。随着种植年限延长,土壤微生物量碳、氮含量多呈显著下降趋势,且两者平均含量均为表层土壤高于深层土壤。不同种植年限下,土壤微生物量碳、氮含量与土壤酶活性之间多呈正相关。综上,不同种植年限的长白楤木土壤理化性质存在明显差异,种植年限越长,土壤脲酶、磷酸酶活性及微生物量碳、氮含量越低,且土壤酶活性与微生物量碳、氮之间的动态变化亦存在一定的响应关系。

In this study,using the soil(0 to 30 cm)with Aralia elata planting for 2,5 and 10 consecu-tive years as test material,the interannual changes of soil enzymes activities and soil microbial biomass carbon and nitrogen and their correlations were analyzed with a view to providing references for growth,cultivation and management of A.elata.The results showed that planting year of A.elata had significant effects on soil enzymes activities.The activity of soil urease and phosphatase showed decreasing trends with the extension of planting years,while that of sucrase showed the opposite trend.As a whole,the activities of urease,phosphatase and sucrose were higher in surface soil compared to deep soil.The contents of soil microbial biomass carbon and ni-trogen mostly showed significantly downward trends with the extension of planting years,and their average con-tents were higher in surface soil compared to deep soil.Under different planting years,soil microbial biomass carbon and nitrogen contents and soil enzymes activities were mostly correlated positively.To sum up,there were obvious differences in soil physical and chemical properties with different planting years of A.elata;the longer the planting year was,the lower the soil urease and phosphatase activities and the microbial carbon and nitrogen contents were;and the soil enzymes activities also had a certain response relationships with the dy-namic change of the microbial carbon and nitrogen contents.