『Abstract
　In this study we evaluate the dynamics of the biophile element phosphorus (P) in the catchment and proglacial areas of the Rhone（oの頭に＾） and Oberaar glaciers (central Switzerland). We analysed erosion and dissolution rates of P-containing minerals in the subglacial environment by sampling water and suspended sediment in glacier outlets during three ablation and two accumulation seasons. We also quantified biogeochemical weathering rates of detrital P in proglacial sedimentary deposits using two chronosequences of samples of fresh, suspended, material obtained from the Oberaar and Rhone（oの頭に＾） water outlets, Little-Ice-Age (LIA) moraines and Younger Dryas (YD) tills in each catchment. Subglacial P weathering is mainly a physical process and detrital P represents more than 99％ of the precipitation-corrected total P denudation flux (234 and 540 kg km^-2 yr^-1 for the Rhone（oの頭に＾） and Oberaar catchments, respectively). The calculated detrital P flux rates are three to almost five times higher than the world average flux. The precipitation-corrected soluble reactive P (SRP) flux corresponds to 1.88-1.99 kg km^-2 yr^-1 (Rhone（oの頭に＾）) and 2.12-2.44 kg km^-2 yr^-1 (Oberaar), respectively. These fluxes are comparable to those of tropical rivers draining transport-limited, tectonically inactive weathering areas.
　In order to evaluate the efficiency of detrital P weathering in the Rhone（oの頭に＾） and Oberaar proglacial areas, we systematically graded apatite grains extracted from the chronosequence in each catchment relative to weathering-induced changes in their surface morphologies (grades 1-4). Fresh apatite grains are heavily indented and dissolution rounded (grade 1). LIA grains from two 0-10 cm deep moraine samples show extensive dissolution etching, similar to surface grains from the YD profile (mean grades 2.7, 3.5 and 3.5, respectively). In these proglacial deposits, the weathering front deepens progressively as a function of time due to biocorrosion in the evolving acidic pedosphere, with mechanical indentations on grains acting as sites of preferential dissolution. We also measured iron-bound, organic and detrital P concentrations in the chronosequence and show that organic and iron-bound P has almost completely replaced detrital P in the top layers of the YD profiles. Detrital P weathering rates are calculated as 310 and 280 kg km^-2 yr^-1 for LIA moraines and 10 kg km^-2 yr^-1 for YD tills. During the first 300 years of glacial sediment exposure P dissolution rates are shown to be approximately 70 times higher than the mean global dissolved P flux from ice-free continents. After 11.6 kyr the flux is 2.5 times the global mean. These data strengthen the argument for substantial changes in the global dissolved P flux on glacial-interglacial timescales. A crude extrapolation from the data described here suggests that the global dissolved P flux may increase by 40-45％ during the first few hundred years of a deglaciation phase.』

1. Introduction
2. Field areas, sampling, soil identifications and methods
　2.1. Field areas
　2.2. Sampling
　　2.2.1. Sampling of outlet water, snow and precipitation
　　2.2.2. Sampling of chronosequences
　2.3. Soil parameters and identifications
　2.4. Methods
　　2.4.1. Phosphorus concentrations in glacier outlet and precipitation samples
　　2.4.2. Preparation and analysis of apatite grains
　　2.4.3. Analysis of TiO2 and SEDEX-extracted P phases in proglacial and suspended sediment samples
　2.5. Corrections for precipitation input
　2.6. Quantifying total P flux rates
　2.7. Quantifying detrital P weathering rates in the proglacial chronosequences
3. Results
　3.1. Phosphorus concentrations in outlet waters and precipitation
　3.2. Phosphorus flux rates in glacier outlet waters and precipitation
　3.3. Biogeochemical weathering and surface morphology of apatite grains in the Rhone（oの頭に＾） and Oberaar chronosequences
　3.4. SEDEX-extracted P phases in the Rhone（oの頭に＾） and Oberaar chronosequences
　3.5. Detrital phosphorus weathering rates in the chronosequences
4. Discussion and conclusions
　4.1. Subglacial mobilisation of phosphorus
　4.2. Proglacial mobilisation of phosphorus
　4.3. Glaciers, glaciations and potential changes in the global phosphorus cycle
Acknowledgments
References