Partitioning of soil respiration in a first rotation beech plantation

A. Jonay Jovani Sancho, Stephanie Brosnan, Kenneth A. Byrne

Research output: Contribution to journalArticlepeer-review

Abstract

Total soil respiration (RTOT) and its components fluxes: autotrophic respiration (RA) and heterotrophic respiration (RH) need to be quantified because they are an important process contributing 60-80% of all ecosystem respiration. Although RTOT is influenced by many environmental factors, the main con- trolling factors are soil temperature and soil moisture content. The relationship between RTOT and soil temperature is usually described using an exponential function. However, a wide variety of soil mois- ture content-response functions have been proposed. This underlines the large variability observed between soil and site types and the need for more investigation. Four paired plots were established in a beech plantation in south-west Ireland. In each pair, one plot was trenched and the other remained undisturbed. Soil respiration was measured at weekly or fortnightly intervals throughout 2010 using an infrared gas analyser. At the same time, soil temperature and soil moisture content in the top 5cm were measured manually and also logged at 30-min intervals. Simple and multiple nonlinear regres- sion analyses were used to examine relationships between soil respiration, soil temperature and soil moisture content. Soil respiration showed a seasonal trend that was regulated by soil temperature. The multiplicative combined models developed support the hypothesis that the effect of soil temperature on soil respiration was dependent on changes in soil moisture content. Maximum soil respiration occurred when the soil moisture content was at field capacity (soil moisture content of 31%) and mean annual RH and RA were 1,700 and 892g CO2 m-2 y-1, respectively. Mean RA represented 34% of RTOT. The inclusion of some soil physical properties (soil organic carbon, bulk density and pH) in soil respiration models could help to explain the spatial variability of soil CO2 efflux at a site level and to improve the annual soil CO2 emissions.

Original languageEnglish
Pages (from-to)91-105
Number of pages15
JournalBiology and Environment
Volume117B
Issue number2
DOIs
Publication statusPublished - 1 Jan 2017

Fingerprint

Dive into the research topics of 'Partitioning of soil respiration in a first rotation beech plantation'. Together they form a unique fingerprint.

Cite this