湖南植烟土壤磷的主要形态及其有效性

为研究湖南主要成土母质植烟土壤磷素的形态及含量特征,阐明土壤磷形态、转化及与有效性的关系,本研究通过对湖南主产烟区4种主要成土母质的16个代表性土壤进行分析,结果表明：不同母质植烟土壤磷的主要形态是无机磷,占土壤全磷的63.82%～77.77%,有机磷仅占22.23%～36.18%。板页岩和紫色板页岩发育的土壤全磷含量较高,为834.63～991.86 mg/kg,但速效磷含量较低,为29.53～30.02 mg/kg；第四纪红土和石灰岩发育的土壤全磷和无机磷的含量较低,而速效磷含量及其占全磷的比例则较高。不同母质植烟土壤有机磷、无机磷和速效磷含量存在有：第四纪红土＞石灰岩＞紫色板页岩和板页岩的变化趋势。不同母质植烟土壤速效磷与土壤全磷、有机磷和无机磷之间均无直接的相关性。

Phosphorus Forms and Availability of Hunan Tobacco-planting Soil

In order to study phosphorus forms and availability of Hunan tobacco-planting soil and illustrate the relationship among soil phosphorus forms, transportation and effectiveness, 16 representative soil samples of 4 main parent materials from Hunan tobacco-growing area were analyzed. The results showed that inorganic P was the main form of different parent materials planting tobacco soil phosphorus, which accounted for 63.82%-77.77% of total P, organic P only accounted for 22.23%-36.18%. The content of total P was relatively high in plate shale and purple slate of 834.63-991.86 mg/kg, but the available P content was low of 29.53-30.02 mg/kg; the contents of total P and inorganic P were low, but the content of available P and its proportion in total P in quaternary red clay and limestone were high. The order of the content of inorganic P, organic P and available P in different parent materials was: quaternary red clay＞limestone＞plate shale and purple slate. Soil available P had no direct correlation with total P, organic P and inorganic P in different parent material tobacco-planting soils.