中文摘要：

草甘膦与磷酸盐具有非常相似的结构,它们在土壤中的主要吸附位点相似,草甘膦可能影响到磷在土壤中的化学行为和有效性。以福建分布最广的红壤、黄壤为对象,采用室内培养试验,研究了草甘膦对2种典型土壤无机磷形态转化及有效性的影响。结果表明：高于2mg·kg^-1的草甘膦显著提高了红壤磷的有效性,而草甘膦对黄壤磷的活化效果不及红壤明显。草甘膦对红壤Al-P和Fe-P的活化作用较强,Ca-P次之,而O-P含量则有所增加,黄壤各形态无机磷在草甘膦作用下均有不同程度地减少。红壤速效磷含量与其pH达显著正相关水平,而与红壤无机磷之间不存在显著相关性;但不同浓度草甘膦作用下红壤Al-P含量与Fe-P、O-P和Ca-P含量存在此消彼长的趋势。黄壤速效磷与Al-P和Fe-P呈显著负相关关系,即Al-P和Fe-P是黄壤速效磷的主要贡献者。

英文摘要：

Glyphosate has been widely applied to weed control in agriculture and forestry and aquatic environment. Structures of glyphosate and phosphate are very similar,which made them have the same adsorption sites in the soil. Accordingly,the glyphosate could affect the chemical behavior of phosphorus and its effectiveness in the soil. An experiment was conducted to study the effects of glyphosate on soil inorganic phosphorus forms and effectivenesS in two typical transformations. The results showed that the addition of glyphosate increased the available phosphate in acidic soils in certain concentration ranges. The effect of glyphosate was correlated to the change of inorganic phosphate components. In red soil, activation of glyphosate to Al-P and Fe-P was the strongest, followed by Ca-P, while O-P content increased. In the yellow soil, the inorganic phosphate components decreased with different degrees after the addition of glyphosate. The content of vailable phosphate significantly and positively correlated to pH （P〈0.05）, the eorrelationship was not found between inorganic phosphate components （P〉0.05）,while Al-P and Fe-P content,O-P and Ca-P content tended to be waxing and waning in red soil. There was significantly negative correlation （P〈0.05） between available phosphate and Al-P,Fe-P,while there is no significant correlation between O-P and Ca-P,so Al-P and Fe-P were major contributor to available phosphate in yellow soil.