不同耕作方式对双序列轮作系统土壤钾素含量及产量的影响

通过设置在甘肃省定西市李家堡镇的保护性耕作措施长期定位试验,于2010年对春小麦、豌豆双序列轮作下的土壤全钾、速效钾含量及作物产量进行了采样测定.试验共设6个处理(T:传统耕作;NT:免耕无覆盖;TS:传统耕作+秸秆还田;NTS:免耕秸秆覆盖;TP:传统耕作+地膜覆盖;NTP:免耕地膜覆盖),采用春小麦和豌豆双序列轮作.结果表明:在0～50cm土层中,免耕和秸秆覆盖措施都可以提高土壤全钾和速效钾含量,其中,免耕秸秆覆盖措施可以显著提高土壤的速效钾含量;在双序列0～50cm土壤中,免耕秸秆覆盖措施下的土壤速效钾含量最高,达388.2mg/kg,传统耕作措施下的土壤速效钾含量最高,为351.68mg/kg.地膜覆盖处理的土壤全钾和速效钾的含量与免耕覆盖、传统耕作+秸秆还田和免耕秸秆覆盖措施下的土壤全钾和速效钾含量相比含量较低;在0～50cm土层中,土壤全钾和速效钾的含量均随着土壤深度的增加而降低.覆膜处理和秸秆覆盖均有助于提高作物产量,免耕对作物产量的影响与传统耕作相比较没有显著差异.

Effects of tillage measures on the soil potassium contents and yields in the double sequence rotation system

The total potassium content,available potassium content and the yield of wheat and pea under the double sequence rotation were determined in 2010 by means of setting the long period protective cultivation experiment in Lijiabao Town,Dingxi City,Gansu Province.Six treatments were set in the experiment(T: traditional cultivation;NT: non-cultivated cover;TS: traditional cultivation+ returning straw into the field;NTS: non-cultivated covering;TP: traditional cultivation + plastic mulch;NTP: non-cultivated plastic mulch),and the double sequence rotation of wheat and pea was taken.The results showed that the measure of non-cultivation and plastic mulch could increase the contents of total potassium and available potassium.And the measure of non-cultivated straw covering could rapidly increase the available potassium content.The content of total soil potassium and available soil potassium under the treatment of plastic mulch decreased with soil depth in 0~50 cm soil layer.Both of the measures of plastic mulch and straw covering increased the yields,non-cultivation had no obvious differences to the traditional cultivation on the yields.