Premium
Effects of soil frost on nitrogen net mineralization, soil solution chemistry and seepage losses in a temperate forest soil
Author(s) -
HENTSCHEL KERSTIN,
BORKEN WERNER,
ZUBER TOBIAS,
BOGNER CHRISTINA,
HUWE BERND,
MATZNER EGBERT
Publication year - 2009
Publication title -
global change biology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 4.146
H-Index - 255
eISSN - 1365-2486
pISSN - 1354-1013
DOI - 10.1111/j.1365-2486.2008.01753.x
Subject(s) - mineralization (soil science) , soil water , snowmelt , dissolved organic carbon , frost heaving , snow , environmental science , forest floor , soil science , hydrology (agriculture) , environmental chemistry , chemistry , geology , geomorphology , geotechnical engineering
Freezing and thawing may alter element turnover and solute fluxes in soils by changing physical and biological soil properties. We simulated soil frost in replicated snow removal plots in a mountainous Norway spruce stand in the Fichtelgebirge area, Germany, and investigated N net mineralization, solute concentrations and fluxes of dissolved organic carbon (DOC) and of mineral ions (NH 4 + , NO 3 − , Na + , K + , Ca 2+ , Mg 2+ ). At the snow removal plots the minimum soil temperature was −5 °C at 5 cm depth, while the control plots were covered by snow and experienced no soil frost. The soil frost lasted for about 3 months and penetrated the soil to about 15 cm depth. In the 3 months after thawing, the in situ N net mineralization in the forest floor and upper mineral soil was not affected by soil frost. In late summer, NO 3 − concentrations increased in forest floor percolates and soil solutions at 20 cm soil depth in the snow removal plots relative to the control. The increase lasted for about 2–4 months at a time of low seepage water fluxes. Soil frost did not affect DOC concentrations and radiocarbon signatures of DOC. No specific frost effect was observed for K + , Ca 2+ and Mg 2+ in soil solutions, however, the Na + concentrations in the upper mineral soil increased. In the 12 months following snowmelt, the solute fluxes of N, DOC, and mineral ions were not influenced by the previous soil frost at any depth. Our experiment did not support the hypothesis that moderate soil frost triggers solute losses of N, DOC, and mineral ions from temperate forest soils.