关键词: 着色, 着色

Abstract:

In order to clarify the distribution characteristics of phosphorus in different types and use patterns of soil and assess the risk of phosphorus’s loss, the content and profile distribution of phosphorus in three typical soils (red soil, alluvial soil, purple soil) was studied. Sample of dry land and paddy soil profile, coming from three parent materials, collected in the field were analyzed in laboratory to classify the inorganic phosphorus according to the fractional analysis method in acidic soil proposed by Zhang Shoujing. The results showed that: the levels and forms in different soil showed a marked difference: the sequence of phosphorus content from high to low was alluvial soil, red soil, purple soil. Al-P and Fe-P had a high percentage in acidic soil, while Ca-P in alluvial soil and purple soil. Phosphorus’s level was the highest in surface soil, and then its content decreased firstly and then tended to be relatively stable. Al-P, Fe-P and O-P mainly enriched in 0-20 cm soil layer and their distribution trend in the profile was similar to the total P, yet Ca-P had a little change in the profile. Because of different land use pattern, the content of the total P also showed a difference: paddy>dry land. Different types and utilization of soils had a significant effect on content and morphological characteristics of phosphorus, so the control of the risk of phosphorus’ loss should be based on different soil types and utilization.