Kuo,Y.-M., Harris,W.G., Munoz（nの頭に〜）-Carpena,R., Rhue,R.D. and Li,Y.(2009): Apatite control of phosphorus release to runoff from soils of phosphate mine reclamation areas. Water Air Soil Pollut., 202, 189-198.

『燐酸塩鉱山再生地域の土壌からの流出に対するリン放出の燐灰石コントロール』

『Abstract
　Phosphorus (P) in runoff can pose a water quality risk in phosphate mine reclamation areas. High dissolved P (DP) concentrations (about 0.4-3.0 mg L-1) in runoff from these areas and high equilibrium P concentrations for the soils led us to hypothesize that P release is controlled by dissolution of apatite rather than by desorption mechanisms. Objectives were to (a) verify via chemical- and solid-state assessments that P in the reclamation soils is mainly in the form of apatite and (b) examine evidence that DP concentrations in runoff water from these soils is controlled by apatite dissolution. Soil analyses included total P (TP), P sorption isotherms, P fractionation, mineralogy, and P distribution by particle size classes. Runoff samples were chemically characterized and modeled for speciation. Results showed high TP concentrations and the presence of apatite. The Ca- and Mg-bound P accounted for about 95％ of TP. Runoff samples were undersaturated with respect to apatite. A strong relationship between calculated apatite specific surface area and measured DP concentration in water extracts is supportive of other evidence that apatite dissolution is a major factor controlling P release from these soils. Data indicate that these soils will be a long-term P source rather than sink. Results are applicable to other phosphate mine reclamation sites and illustrate the need to account for compositional differences between reconstructed soils on reclaimed mining sites and their indigenous soil analogues.

Keywords: Dissolved phosphorus; Specific surface area; Apatite; Dissolution; Reclamation area; Surface runoff』

1. Introduction
2. Materials and methods
　2.1. Field sampling
　2.2. Soil chemical properties
　　2.2.1. Mehlich-1 extraction
　　2.2.2. P sorption isotherms
　　2.2.3. P fractionation
　　2.2.4. TP in each particle fraction
　　2.2.5. Solid state assessments
　2.3. Phosphate solubility equilibria
　2.4. Approach for calculating CFA SSA
3. Results and discussion
　3.1. Soil properties
　3.2. Results of phosphate solubility equilibria
　3.3. Relation between CFA SSA and DP concentration
4. Conclusions
Acknowledgments
References

ホームへ