摘要
对黄土旱塬定位施肥20年后土壤中不同磷素形态在土层中的空间分布及有效性进行了研究。结果表明,在不同施磷水平上,磷素在土壤表层发生累积。随着磷肥用量的增加,表层的全磷和有效磷的含量逐渐增加;而在下层土壤中虽有微量增加,但增幅不明显。说明长期合理施用磷肥可显著扩大土壤中的有效磷库。黄土旱塬区长期定位试验土壤表层中无机磷以Ca-P为主,占无机磷总量的80%以上。随着施磷量的增加,无机磷组分Ca_2-P、Ca_8- P、Al-P和Fe-P在土壤中的含量总体上都呈增加的趋势。通过有效磷与无机磷各组分的相关性分析及通径分析看出,Ca_2-P和Ca_8-P可称为有效磷源,O-P与Ca_(10)-P为潜在磷源,而Al-P和Fe-P介于二者之间。其中,Fe-P主要是通过影响其它组分而间接影响有效磷的含量。
The spatial distribution and availability of soil phosphorus （P） in Loess Plateau after 20 years of phosphate fertilization was investigated in this study. Phosphorus mainly accumulated in the surface layer after long-term fertilization. Soil total P and Olsen-P increased gradually with fertilization rate, which indicated that long-term continuous fertilization could increase the available phosphorus storage significantly. Ca-P was the main fraction in soil inorganic P, which accounted for above 80% of the inorganic P. The contents of soil Ca2-P,Ca8-P,Al-P and Fe-P increased with the phosphate fertilization rate. Correlation analysis and path analysis showed that soil Olsen-P was significantly correlated with soil inorganic P, Ca2-P and Ca8-P, which can be the source of soil available P. Soil O-P and Ca10-P, the potential sources of soil available P, had low correlations with soil Olsen-P. Soil Al-P and Fe-P had a medium correlation with soil Olsen-P, and in particular, Fe-P affected soil Olsen-P indirectly through other fractions.
出处
《植物营养与肥料学报》
CAS
CSCD
北大核心
2008年第3期424-430,共7页
Journal of Plant Nutrition and Fertilizers
基金
国家重点基础研究发展规划项目(2005CB121102)
国家自然科学基金项目(30500077)资助。
关键词
磷素
长期定位施肥
空间分布
有效性
无机磷组分
phosphorus
long-term positional fertilization
spatial distribution
availability
inorganic P fraction
