The nutrient features of 345 samples of 4 soil types from Bijie tobacco-growing area were analyzed. The results showed that:(1)The soil pH-value was in the range of 4.46~7.65,and the proportions of various soil types with suitable pH-value(5.0~7.0)for flue-cured tobacco growth were yellow brown soil 91.43%, yellow soil 85.78%, purple soil 69.57%, and lime soil 52.22%.(2)The average contents of organic matter in different soil types were generally high, and yellow soil had the highest organic matter content(28.75 g/kg), followed by lime soil(27.54 g/kg), yellow brown soil(26.35 g/kg)and purple soil(23.76 g/kg).(3)The proportions of soil types with suitable available phosphorus content(10~40 mg/kg)for flue-cured tobacco growth were yellow brown soil 80.00%, purple soil 73.92%, lime soil 73.43%, and yellow soil 70.56%.(4)The pro-portions of soil types with available potassium content over the critical value 150 mg/kg were yellow brown soil 88.56%,lime soil 83.33%, yellow soil 83.60%, and purple soil 56.52%.(5)The content of water-soluble chlorine in purple soil was below 30 mg/kg, and the yellow soil, yellow brown soil and lime soil with over 30 mg/kg water-soluble chlorine content accounted for 4.57%,2.86% and 2.22%,respectively.(6)The proportions of soil types with available boron content less than the critical val-ue 0.5 mg/kg were yellow soil 54.82%, yellow brown soil 48.57%, lime soil 26.67%, and purple soil 26.07%. The proportions of soil types with available copper content below the critical value 0.2 mg/kg were yellow brown soil 14.29%, lime soil 1.11%, yellow soil 1.02%, and purple soil 0%. The yellow soil and lime soil with available zinc content below the critical value 1.0 mg/kg accounted for 18.79% and 10.00%, respectively, while the content of available zinc in both yellow brown soil and purple soil was more than the critical value. The contents of available manganese and available iron in 4 soil types were all at high or very high level.%对毕节烟区4种土壤类型的345个土壤样品进行了养分分析,结果表明:(1)pH值介于4.46~7.65之间,适宜烤烟生长的比例分别为黄棕壤(91.43%)>黄壤(85.78%)>紫色土(69.57%)>石灰土(52.22%).(2)有机质含量较为丰富,依次为黄壤(28.75 g/kg)>石灰土(27.54 g/kg)>黄棕壤(26.35 g/kg)>紫色土(23.76 g/kg).(3)速效磷适宜烤烟生长的比例分别为黄棕壤(80.00%)>紫色土(73.92%)>石灰土(73.34%)>黄壤(70.56%).(4)速效钾在临界值以上的比例为黄棕壤(88.56%)>石灰土(83.33%)>黄壤(83.6%)>紫色土(56.52%).(5)紫色土水溶性氯均在30 mg/kg以下,大于30 mg/kg所占比例分别为黄壤(4.57%)>黄棕壤(2.86%)>石灰土(2.22%).(6)有效硼低于临界值的比例分别为黄壤(54.82%)>黄棕壤(48.57%)>石灰土(26.67%)>紫色土(26.07%);有效铜含量低于临界值的比例以黄棕壤最高14.29%,黄壤和石灰土分别为1.02%和1.11%,紫色土均高于临界值;有效锌含量低于临界值的比例黄壤和石灰土分别为18.79%和10.00%,黄棕壤和紫色土均高于临界值;有效锰和有效铁含量全部为高或极高水平.
展开▼
