旱作条件下不同母质红壤磷吸附作用及其影响因素研究

为深入了解不同母质发育旱地红壤对磷元素的吸附特性，以不同母质发育的旱地红壤为研究对象，在不同肥力等级下对土壤磷素吸附特性及其影响因素进行比较分析，并对供试红壤的标准需磷量进行了预测。结果表明：不仅不同母质发育的红壤旱地对磷素具有不同的吸附特性，即使是同一母质发育的不同肥力水平的土壤对磷的吸附能力也存在差异。不同母质发育红壤的吸磷能力以红黏土母质最强，不仅吸磷容量大，吸附的磷也最难解吸。黏粒含量对土壤磷素吸附的影响最大，与各吸附参数的相关性均达到极显著水平，活性铝对磷素吸附的影响也较大，有效磷含量和pH与土壤磷素吸附呈负相关。不同母质发育土壤的需磷量差异较大，并且明显高于当地施肥水平。

Study on Phosphorous Sorption and Its Influencing Factors of Red Soil Derived From Different Parent Materials Under Dry-farming Condition

In order to study the characteristic of phosphorous sorption of red soil derived from different parent materials under dry-farming condition, the author used soil derived from different parent materials as study object and comparatively analyzed the soil phosphorous sorption characteristic under different fertility degrees, and forecasted the phosphorus requirement of red soil. The results showed that both soil parent material and fertility degree had different influence on phosphorus sorption ability. The soil derived from red clay parent material had the strongest ability of phosphorous sorption, high sorption capacity and the weakest ability of phosphorous desorption. Clay particle content was the most important influencing factor on soil phosphorous sorption, and its correlation with all phosphorous adsorption parameters reached highly significant level, the activated alumina also had significant effect on phosphorous sorption, and the content of available phosphorus and pH had a negative correlation with phosphorus sorption. The phosphorus requirement had great difference among different parent materials, and it was significantly higher than the local fertilization level.