渝东南烟区土壤pH分布特点及其与土壤养分的关系

Distribution of Soil pH and Correlation to Soil Nutrient in Tobacco-planting Arcas of the Southeast of Chongqing

为渝东南烟区实施平衡施肥、改善土壤环境提供科学依据,采用GPS定位取样的方法对渝东南烟区典型性产烟县彭水县和武隆县的土壤pH分布特点及其与土壤养分的关系进行研究。结果表明：渝东南植烟土壤酸化严重,最适宜烟草生长的土壤pH 5.5-6.5仅占36.36%;渝东南植烟土壤有效态元素含量差异明显,有效硼、有效钼含量极低,水溶性氯含量适宜,碱解氮、交换性镁含量适宜或丰富,有效磷、交换性钙含量差异较大,各级所占比例均衡;土壤pH与土壤有效磷、碱解氮、有效铜、有效锌和有效铁含量之间呈极显著负相关（p〈0.01）,与交换性钙、交换性镁含量之间呈极显著正相关（p〈0.01）;

To provide a scientific basis for balanced fertilization and improving soil setting,the authors used the method of GPS location system to take soil samples.The distribution of soil pH and the correlation to soil nutrient were analyzed from 131 soil samples which were collected from the typical tobacco-planting county Pengshui and Wulong in southeast of Chongqing.Results：Tobacco-planting soil acidification in southeastern of Chongqing is serious, and the most suitable tobacco grown soil pH 5.5-6.5 accounted for only 36.36%;There are significant differences in content of soil available elements in the southeast of Chongqing.The content of available boron,molybdenum is extremely low;It is suitable of water-soluble chlorine content;And the content of nitrogen, exchangeable magnesium is suitable or rich; However,the content of phosphorus, exchangeable calcium are different, and the distribution of proportion in all levels is well-balanced;Soil pH-value was highly significantly negatively correlated with the content of soil available phosphorus,nitrogen,Cu,Zn,iron pH-value,and highly significantly positively correlated with the content of exchangeable Ca,magnesium;Compared pH≤4.5 with 5.5 〈pH≤6.5,the content of soil organic matter,available nitrogen,K,iron,Zn,Cu,Zn is higher.However,the content of water soluble chloride,available manganese,exchangeable calcium, magnesium is lower.