Assessment of phosphate solubility in forest and highly fertilized Andisols and Andic soils
作者:
M. A. Negrín,
M. Espino‐Mesa,
J. M. Hernández‐Moreno,
期刊:
Communications in Soil Science and Plant Analysis
(Taylor Available online 1998)
卷期:
Volume 29,
issue 7-8
页码: 901-911
ISSN:0010-3624
年代: 1998
DOI:10.1080/00103629809369994
出版商: Taylor & Francis Group
数据来源: Taylor
摘要:
Phosphate solubility in Andisols and Andic soils (forest and fertilized) has been studied in soil solutions at two soil:solution ratios (1:2.5 and 1:25). Forest soils approached the variscite solubility (pIAP=30.4±0.3) while fertilized soils were closer to the amosphous analog of variscite (pIAP= 29.8±0.2). In some samples, phosphorus (P) activities were consistent with simultaneous equilibrium between aluminum (Al) and iron (Fe) phosphates. The dilution ratio, DR=10(P)1:25/(P)l:25, was 10.0±0.4 for all samples. This suggests a dissolution of phosphate minerals attaining apparent saturation in 24 h. However, the high content of dissolved organic carbon and Al in aqueous extracts also pointed to the existence of soluble ternary complexes of P with Al(Fe)‐humus complexes. These results could be consistent with simultaneous control between the dissolution of variscite‐like minerals and humus‐Al(Fe)‐P associations. Nevertheless, DR seems a valuable criterion to assess soil P status, especially in fertilized soils with high active Al and Fe contents.
点击下载:
PDF (516KB)
返 回