昭通植烟土壤的有机质与氮含量

在昭通市8个产烟县(区)采集605个植烟耕层土壤进行分析。结果表明,昭通植烟土壤有机质和全氮含量中偏高,平均含量分别为2.63%和0.13%,处于中上以上水平含量的土壤样本分别占76.19%和67.6%。速效氮含量平均107.28 mg/kg,处于中上以上水平含量的土壤样本占95.37%。各产烟县(区)植烟土壤有机质和全氮含量地域分布差异较大,其中镇雄县和威信县较高,巧家县和永善县较低。全市植烟土壤有机质和氮素含量从地理分布上表现出由南向北递增、自东向西递减的趋势。

The Content of Organic Substance and Nitrogen in Zhaotong Tobacco Growing Soils

605 soil samples were collected and analyzed from 8 tobacco growing counties in Zhaotong.The results showed that content of organic substance and total nitrogen was moderate and higher,with the average being 2.63% and 0.13% for organic substance and total nitrogen,respectively.The content of organic substance and total N in moderate and higher grades accounted for 76.19% and 67.6% respectively.The mean content of available nitrogen was 107.28 mg/kg,and of all the soil samples,those in moderate and higher grades accounted for 95.37%.Great difference existed in the regional distribution of both organic substance and nitrogen content in 8 tobacco growing counties.The content of organic substance and nitrogen was higher in Zhenxiong and Weixin counties,but lower in Qiaojia and Yongshan counties.The content of organic substance and nitrogen in geographical distribution tended to increase progressively from south to north and decrease successively from east to west.