老挝主要旱作区表层土壤养分含量与肥力评价

Evaluation on Topsoil Nutrient Content and Fertility of Main Dryland Areas in Laos

采集老挝南、北部主要旱作区土壤0~20cm层样品57个,分析土壤pH、有机质、全氮、速效氮、有效磷、速效钾、交换性钙、交换性镁和有效锌含量,评价旱作区表层土壤养分肥力现状并探讨区域表层土壤养分含量差异。结果表明,老挝主要旱作区表层土壤偏酸,总体肥力水平良好,交换性钙和镁含量偏低。老挝南、北部旱作区表层土壤不同养分含量有差异。建议在土壤偏酸的旱地施用石灰或碱性肥料以提高土壤pH,增加土壤钙、镁供应量,增施有机肥以提高土壤保肥保水能力,同时注意氮磷钾肥的施肥比例,平衡施肥。

This study was conducted to explore the differences in nutrient contents and evaluated soil fertility situation of surface soil in main dry land areas,and analyzed soil pH,the contents of soil organic matter,total nitrogen,available nitrogen,available phosphorus,available potassium,available calcium,available magnesium and available zinc by collecting 57 samples of the 0-20 cm cultivated soil layer from dry lands in the northern and southern part of Laos.The results showed that the main dry land areas of Laos was meta-acid,the overall nutrient fertility level was good.The available calcium and available magnesium was at the lower level.The soil nutrient contents of dry lands were different in southern and northern provinces.It is suggested that lime or other alkaline fertilizers should be applied on the farmland with acid soil,and calcium,magnesium fertilizers should be added to improve soil nutrient fertility.Organic fertilizer should be applied to improve soil water retention capacity,at the same time pay attention to the proportion of phosphatic and potash fertilizer.