Uni-Bayreuth grafik-uni-bayreuth



Environmental and climatic controls over CO2 efflux and DOC leaching in a 1-year soil incubation experiment

TERRECO Cluster F-08

From 11/2012

Principal Investigator: Ji-Hyung Park
Staff: Mohammad Moonis

Abstract 2013: Carbon stored in forest soils represents one of the largest terrestrial carbon pools. The factors that control soil carbon stabilization could be the physical protection of organic matter, substrate quality, and climatic factors like temperature. Recent studies have shown that it is not only the quality of organic matter but also environmental conditions that actually govern the stability of soil carbon. In this study, chemical controls in the form of nitrogen and liming application have been examined under two different incubation temperatures To test whether nitrogen deposition and soil acidification can have negative effect on soil CO2 efflux and dissolved organic carbon (DOC) leaching. Soil samples collected from a young mixed deciduous forest in Haean  Basin, South Korea and an old beech-dominated forest in Steigerwald Nature Park, Germany, were incubated in control (100 C) and elevated temperature (150C-German samples were put in control temperature only). CO2 efflux and DOC export via soil leachates were analyzed at the intervals of 2-4 weeks. CO2 efflux and pH increased briefly but thereafter differed little between the treatments in response to warming and N-fertilization. However, the overall soil respiration was lower in nitrogen application in comparison to liming and untreated samples of Korean soil. DOC concentrations continued to decrease in leachates from all treatments, but increased in Korean samples after application of second liming dose. The second liming also increased pH in Korean and German samples. Aromatic load in the form of SUVA increased sharply in the leachates in the beginning and decreased gradually from then without any differences among the treatments. The short term increase CO2 in both treatments suggest that available carbon for degradation was used up in the begining. But increase in DOC export after second liming dose implies differential response mechanism of gaseous and aquatic loss of carbon. More studies on the effect of liming- and N-induced effects on soil carbon chemistry and the composition of microbial communities responsible for soil carbon decomposition.

Keywords: CO2 efflux, DOC, leaching, forest soils, forest carbon balance, liming, soil temperature response


Poster January 2013


last modified 2013-03-07