ISSN:
1573-2932
Source:
Springer Online Journal Archives 1860-2000
Topics:
Energy, Environment Protection, Nuclear Power Engineering
Notes:
Abstract Soils from the C-horizon of deciduous forests in southern Sweden, originally sampled in 1947-52, were resampled in 1988. Air-dried soil from both periods were extracted in 1991 using M NH4Ac, pH 4.8, and 0.2 M HNO3 for analysis of exchangeable and acid soluble pools of Na, Mn, Ca, Mg, K, Sr, Zn, Fe, S, P, and Al. Using acid NH4Ac as extractant nine elements had changed significantly (p〈0.05) over 40 yr. In particular, the pools of exchangeable base cations and Mn had decreased, whereas those of Al, S, and Fe had increased. The HNO3 extraction showed the same tendency as NH4Ac for most elements, but the relative changes were always smaller. The largest decrease was measured in Na with both extractants (only 10 to 30% remaining in 1988). Of K, Mg, Ca, and Sr, about 40 to 60% remained with NH4Ac and about 70% with HNO3. The NH4Ac exchangeable pool of Al, on the contrary, was twice as high in 1988 as in 1947–52. Amounts obtained with the two extractants were usually positively correlated (r〉0.90 for Na, K, Mg, and Sr), but with the exception of S, values for HNO3 were higher or much higher. It is concluded that a decided decrease of the exchangeable pools of base cations and an equally decided increase of exchangeable Al has occurred even in the C-horizon, well below the main rhizosphere. That also the acid soluble pools of base cations have decreased indicates mineralogical changes which may counteract a complete reversibility of the current soil acidification.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/BF00483359
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