Root trenching: a useful tool to estimate autotrophic soil respiration? A case study in an Austrian mountain forest |
| |
Authors: | Eugenio Díaz-Pinés Andreas Schindlbacher Michael Pfeffer Robert Jandl Sophie Zechmeister-Boltenstern Agustín Rubio |
| |
Institution: | (1) Silvopasciculture Department, Madrid Polytechnic University, 28040 Madrid, Spain;(2) Federal Office and Research Centre for Forests, 1131 Vienna, Austria |
| |
Abstract: | We conducted a trenching experiment in a mountain forest in order to assess the contribution of the autotrophic respiration
to total soil respiration and evaluate trenching as a technique to achieve it. We hypothesised that the trenching experiment
would alter both microbial biomass and microbial community structure and that fine roots (less than 2 mm diameter) would be
decomposed within one growing season. Soil CO2 efflux was measured roughly biweekly over two growing seasons. Root presence and morphology parameters, as well as the soil
microbial community were measured prior to trenching, 5 and 15 months after trenching. The trenched plots emitted about 20
and 30% less CO2 than the control plots in the first and second growing season, respectively. Roots died in trenched plots, but root decay
was slow. After 5 and 15 months, fine root biomass was decreased by 9% (not statistically different) and 30%, (statistically
different) respectively. When we corrected for the additional trenched-plot CO2 efflux due to fine root decomposition, the autotrophic soil respiration rose to ~26% of the total soil respiration for the
first growing season, and to ~44% for the second growing season. Soil microbial biomass and community structure was not altered
by the end of the second growing season. We conclude that trenching can give accurate estimates of the autotrophic and heterotrophic
components of soil respiration, if methodological side effects are accounted for, only. |
| |
Keywords: | |
本文献已被 SpringerLink 等数据库收录! |
|