Vincent,A.G., Turner,B.L. and Tanner,E.V.J.(2010): Soil organic phosphorus dynamics following perturbation of litter cycling in a tropical moist forest. European Journal of Soil Science, 61, 48-57.

『熱帯湿潤林におけるリター循環の攪乱後の土壌有機リンのダイナミクス』


Summary
 The productivity of tropical lowland moist forests is often considered to be limited by the availability of phosphorus. Organic phosphorus is often abundant in tropical soils, but its role in forest nutrition is largely unknown. We addressed this by using a large-scale litter manipulation experiment to investigate the stability of soil organic phosphorus in a tropical lowland forest in Central Panama. Three years of litter removal reduced the organic phosphorus concentration in the surface 2 cm of mineral soil by 23%, as determined by NaOH-EDTA extraction and 31P-NMR spectroscopy; this included decreases in phosphate monoesters (20%) and DNA (30%). Three years of litter addition (equivalent to adding 6 kg P ha-1 per year) increased soil organic phosphorus by 16%, which included a 31% increase in DNA. We did not detect higher-order inositol phosphates, despite their abundance in mineral soils of temperate ecosystems. Our observed turnover rate suggests that even the 0 - 2-cm layer of the mineral soil contributes a fifth of the total phosphorus needed to sustain above-ground growth in this forest. Soil organic phosphorus is thus likely to make a more important contribution to the nutrition of semi-evergreen forest plants than has hitherto been acknowledged.』

Introduction
Materials and methods
 Study area
 Gigante Litter Manipulation Project
 Soil sampling and preparation
 Solution 31P NMR spectroscopy
 Other chemical analyses
 Statistical analysis
Results
 Phosphorus fractions
 Phosphorus composition determined by solution 31P NMR spectroscopy
 Total soil carbon and nitrogen
 Discussion
Acknowledgements
References


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