三七不同间隔年限种植土壤中、微量元素动态变化规律研究

目的：研究三七不同间隔种植年限对土壤有效态中、微量元素的影响。方法：对文山州马白、马塘、古木和盘龙4个三七道地产区新土、间隔5年土壤和连作土壤3种种植模式下土壤有效钙、镁、锰、铜、锌和硼含量进行动态测定。结果：三七连做土壤除钙、镁外，其他微量元素及间隔5年土壤全部中、微量元素含量均显著高于新土；间隔5年土壤除硼外其他元素含量均显著高于连做土；土壤有效锰、铜和硼含量受种植模式影响，而锌、钙和镁不受影响；3种种植模式下土壤有效铜和钙含量及连作土有效锌含量季度变化不显著，但有效硼含量随种植时间的增加而增加；新土和间隔5年土壤有效锌含量也随种植时间延长而上升；有效锰和镁含量在次年4月达到峰值，至取样结束降至最低；同新土相比，间隔5年土壤有效锰和铜所占比例增幅分别为29%，114%，镁和硼所占比例降幅分别为18%，38%，锌和钙所占比例变化不显著；连做土壤锰、铜和硼所占比例增幅分别为50%，120%，22%，锌、钙和镁等无显著变化。结论：连作不能引起土壤中、微量元素养分亏缺，而诱发连作障碍，但其造成的三七种植土壤中、微量元素养分比例失衡应为产生连作障碍的原因之一。

Study on dynamic change of middle and micro element in Panax notoginseng plant soils with different interval year

Objective: To study effects of different interval year on Panax notoginseng plant soils middle and micro element content. Method: The dynamic change of Ca, Mg, Mn, Cu, Zn, B from Mabai, Matang, Gumu and Panlong were determined under different planting patterns (new soil, interval 5 years soil and continuous cropping soil). Result: All the micro elements (except Ca, Mg) of interval 5 years soil and continuous cropping soil were significantly higher than those of new soil. All the middle and micro elements (except B) of interval 5 years soil were significantly higher than those of the continuous cropping soil. Planting patterns had remarkable influence on the content of Mn, Cu, B, but not Zn Ca, Mg. Cu, Ca under the 3 planting patterns, and Zn under the continuous cropping pattern did not show significant quarter changes. B content increased with the elongation of implantation time. Zn in new soil and interval 5 years also increased with prolonging of planted time. Mg, Mn and Cu content reached to peak value on April next year, and reached to minimum on the end of this experiment. Compared with new soil, the proportion of Mn, Cu in total elements increased by 29%,114%, Mg, B decreased by 18%, 38%, Zn and Ca changed slightly of interval 5 years soils; In continuous cropping soil, Mn, Cu and B increased by 50%, 120%, 22%, respectively, but Zn, Ca, Mg had no significant change. Conclusion: Continuous cropping pattern could not induce the deficient of soil middle and micro elements, and thereafter might not result in continuous cropping obstacles. But the imbalance proportional of soil middle and micro elements in P. notoginseng plant soils may be one of the main reasons for continuous cropping obstacles.