Mobility of different forms of phosphorus in sandy soils
Predication of the long-term leaching of phosphorus (P) in the soil requires information of soil characteristics and behavior of P forms. This study assessed the mobility of different P forms in sandy soils that have been intensively loaded with P. Two sandy soils with different P concentration were...
Saved in:
| Main Authors: | , |
|---|---|
| Format: | Article |
| Language: | English |
| Published: |
Zhejiang University Press
2010-07-01
|
| Series: | 浙江大学学报. 农业与生命科学版 |
| Subjects: | |
| Online Access: | https://www.academax.com/doi/10.3785/j.issn.1008-9209.2010.04.017 |
| Tags: |
Add Tag
No Tags, Be the first to tag this record!
|
| Summary: | Predication of the long-term leaching of phosphorus (P) in the soil requires information of soil characteristics and behavior of P forms. This study assessed the mobility of different P forms in sandy soils that have been intensively loaded with P. Two sandy soils with different P concentration were collected at two depths (0-10 cm and 10-30 cm) from the vegetable farms in Quzhou and Wenzhou, Zhejiang Province, China. The surface soils (0-10 cm) were spiked with P (in form of KH<sub>2</sub>PO<sub>4</sub>) and amended with CaCO<sub>3</sub> or amorphous iron oxide to obtain soil samples with different P concentration and P forms. A series of 30 cm length leaching column containing 10 cm of amended surface soils varying forms of P above 20 cm of non-amended subsoil were constructed. The soil columns were consecutively leached by 0.002 mol·L<sup>-1</sup> CaCl<sub>2</sub> for 12 cycles. Column leachates were collected for measurement of concentration of total reactive P (TRP), dissolved reactive P (DRP), and reactive particulate P (RPP). Changes of water soluble P, Mehlich Ⅲ -P, and P fractions in the leached soils were characterized. The results showed that addition of amorphous iron oxide and CaCO<sub>3</sub> to soils could significantly change P forms in sandy soils, and decrease soil P availability. Amorphous iron oxide was more effective for decreasing soil P availability than CaCO<sub>3</sub>. Forms of P in leachate presented mainly for DRP, and particulate P ratio of total P ranged from 1.2% to 39.8%. The loss of the TRP and DRP were significantly correlated to P accumulation in surface soils. Both correlation analysis and changes of P forms in the soils before and after leaching indicated that P leached from the soil columns were mainly originated from H<sub>2</sub>O-P and NaHCO<sub>3</sub>-P. Twenty-seven point one percent-54.2% of the P lost from surface soils was leached out from the columns, and the remainder was downward moved into 10-30 cm soils. Addition of iron oxide to sandy soils could enhance the downward transfer of particulate P in columns. |
|---|---|
| ISSN: | 1008-9209 2097-5155 |