Early effects of lime and hardened and non-hardened ashes on pH and electrical conductivity of the forest floor, and relations to some ash and lime qualities

Citation
Hm. Eriksson et al., Early effects of lime and hardened and non-hardened ashes on pH and electrical conductivity of the forest floor, and relations to some ash and lime qualities, SC J FOR R, 1998, pp. 56-66
Citations number
26
Categorie Soggetti
Plant Sciences
Journal title
SCANDINAVIAN JOURNAL OF FOREST RESEARCH
ISSN journal
02827581 → ACNP
Year of publication
1998
Supplement
2
Pages
56 - 66
Database
ISI
SICI code
0282-7581(1998):<56:EEOLAH>2.0.ZU;2-2
Abstract
Wood ash recycling and liming, and combinations of the two, have been sugge sted as being prophylactic measures for maintaining the soil's buffering ca pacity and preventing under-balanced nutrient budgets in forest ecosystems, particalarly in areas where acid deposition is high and/or whole-tree harv est has been practised. To prevent ash additions from negatively impacting the Bora and fauna of the soil floor, application of too easily soluble ash es should be avoided. However, there is a scarcity of knowledge on how the early effects of ash additions correlate with the solubility properties of hardened and non-hardened ashes. In this study, a variety of ash types and ash/lime mixtures and a lime were investigated with respect to their effects on the pH and electrical conduc tivity (EC) of surface layers of a forest soil during the first year after addition. For some ash types, several doses were applied, while other types were divided into fine and coarse material applied separately. Levels of e xchangeable cations in the soil were determined after 11 months for some of the treatments. The correlations between the effects of the ashes and ash/ lime mixtures on the pH and EC, respectively, of the forest soil layers, an d the pH and EC, respectively, of the ashes and ash/lime mixtures, as measu red after diluting to various degrees and shaking for various lengths of ti me were examined. Within three weeks after application, EC increased most in the upper 8 cm o f the soil in all treatments. A hardened ash obtained from burning wood and pear fuels, which had relatively high contents of organic C and S, caused the highest increase in EC. A short-term decrease in pH at 1-8 cm depth was found in cases where large increases in EC were observed. In general, the highest pH values were found after ll months, also at 0-1 cm soil depth. By that time, the lime and most ash treatments had significantly increased th e pH at 0-3 cm soil depth. At ail soil depths, the greatest increase in pH was obtained with an untreated, loose wood ash. Ash granules of the same or igin as the loose ash affected EC only moderately, and the effect on soil p H was not significant on any of the dates during the first year. A prelimin ary test to determine an upper limit for the solubility of spreadable ashes is suggested for practice.