Papers Published
Abstract:
This study examined the accumulation of organic carbon (C) and fractions of soil phosphorus (P) in soils developing in volcanic ash deposited in the 1883 eruption of Krakatau. Organic C has accumulated at rates of 45 to 127 g/m2/yr during 110 years of soil development, resulting in profiles with as much as 14 kgC/m2. Most soil P is found in the HCl-extractable forms, representing apatite. A loss of HCl-extractable P from the surface horizons is associated with a marked accumulation of NaOH-extractable organic P bound to Al. A bioassay with hill rice suggests that P is limiting to plant growth in these soils, perhaps as a result of the rapid accumulation of P in organic forms.