生物碳对新疆灰漠土壤无机磷形态的影响

Effects of Biochar on Inorganic Phosphorus Forms in Grey Desert Soil

[目的]研究生物碳对新疆灰漠土无机磷形态的影响。[方法]室内模拟试验,试验设置三种土壤处理,分别为空白土壤(CK)、施用等碳量的秸秆和生物碳;每种土壤磷肥(P_2O_5)施用量设三个水平,分别为0、0.25和0.5g/kg。[结果]灰漠土无机磷各形态中以Ca_(10)-P为主,占60%以上;其次是Ca_8-P,占20%以上。施用磷肥可以显著提高土壤Ca_2-P、Ca_8-P、Al-P和Fe-P含量,但对O-P和Ca_(10)-P含量均无影响。施用秸秆和生物碳可以提高土壤Ca_2-P含量,尤其是施用生物碳可显著增加土壤Ca_2-P和Al-P含量,但是Ca_8-P和Fe-P含量有所减低。[结论]施用生物碳有助于提高灰漠土壤无机磷的有效性。

[ Objective ] The influence of biochar application on soil inorganic P forms in grey desert soil of Xinjiang was evaluated with a pot experiment. [ Method ] In this study, three soil treatments were set as blank soil （CK）, application of the equal amounts of carbon as cotton straw and biochar to the blank soil, respectively. Each soil treatment was applied at three levels of phosphate fertilizer （ P2O5 ） as 0, 0.25 and 0.5 g/kg. [ Result] The result showed that Ca10 -P was in a dominant position in soil inorganic P, accounting for more than 60% of the total inorganic P; followed by Cas - P, accounting for more than 20% of the total inorganic P. The content of inorganic P, Ca2 - P, Ca8 - P, Al - P and Fe - P in soil was significantly increased by phosphate fertilizer application, but the content of O - P and Ca10 - P was not affected. Ca2 - P in soil was improved by application of cotton straw and biochar. The content of Ca2 - P and Al - P in soil under bioehar treatments was significantly higher than those under cotton straw and CK treatments, but the content of Cas - P and Fe - P in biochar treatments was decreased. [ Conclusion ] Those results suggest that application of bioehar can improve the inorganic P availability in grey desert soil.