三峡库区石漠化地区牛粪中钾元素在土壤-甜高粱体系中的分布与利用

为了研究在施用不同量牛粪后土壤-甜高粱体系中钾元素的利用和分布情况,试验分析了牛粪、甜高粱及土壤试验前后速效钾、全钾含量和甜高粱产量。结果表明:试验前在最浅层(0～≤5 cm)土壤中速效钾含量极显著低于>5～≤10 cm、>10～≤15 cm、>15～≤20 cm土层(P<0.01),4个土层土壤钾含量分别为27.73,43.27,42.97,40.40 mg/kg;试验后各土壤层全钾、速效钾含量与试验前相比均有增加;不同施肥处理对甜高粱速效钾含量的影响不显著(P>0.05);施化肥组甜高粱总产量极显著高于其他各组(P<0.01);钾元素在植株茎叶及根系中的富集作用表现为茎叶>根系。说明单施有机肥不是最佳施肥方式,需要有机肥、无机肥混合施入。

Distribution and utilization of potassium(K) in cow dung in a sweet sorghum-soil in the rocky desertification area of the Three Gorges Reservoir Region

To study the distribution and use of K element in a sweet sorghum-soil system after the application of different dosages of the cow dung,the content of rapidly-available potassium and total potassium were compared in the cow dung and sweet sorghum,and soil before and after the experiment,and the output of sweet sorghum was also analyzed.The results showed that before the experiment the content of rapidly-available potassium in shallow soil 0 to 5 cm was significantly lower(P<0.01) than that of in 5 to 10 cm,10 to 15 cm and 15 to 20 cm layer,which were 27.73 mg/kg,43.27 mg/kg,42.97 mg/kg,40.40 mg/kg respectively;the contents of total potassium and rapidly-availabe potassium in the layers were increased after the experiment compared to before the experiment;the output of sweet sorghum in the chemical fertilizer group was significantly higher than that of in organic fertilizer group;the enrichment of potassium from stem leaf and root in the plants showed that the former was more than the latter.It is concluded that it was not the best way to use organic fertilizers alone,the best way was using mixed inorganic and organic fertilizers.