Peer-Reviewed Journal Details
Mandatory Fields
Sancho, AJJ,Brosnan, S,Byrne, KA
2017
May
Biology And Environment-Proceedings Of The Royal Irish Academy
PARTITIONING OF SOIL RESPIRATION IN A FIRST ROTATION BEECH PLANTATION
Published
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Optional Fields
TEMPERATE DECIDUOUS FOREST CO2 EFFLUX ROOT RESPIRATION HETEROTROPHIC RESPIRATION ECOSYSTEM RESPIRATION SPATIAL VARIABILITY TEMPORAL VARIATION CONIFEROUS FOREST ORGANIC-MATTER CLIMATE-CHANGE
117B
91
105
Total soil respiration (R-ToT) and its components fluxes: autotrophic respiration (R-A) and heterotrophic respiration (R-H) need to be quantified because they are an important process contributing 60-80% of all ecosystem respiration.Although R-ToT is influenced by many environmental factors, the main controlling factors are soil temperature and soil moisture content.The relationship between R-ToT and soil temperature is usually described using an exponential function. However, a wide variety of soil moisture 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 regression 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 R-H and R-A were 1,700 and 892g CO2 m(-2) y(-1), respectively. Mean RA represented 34% of Rior 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.
10.3318/BIOE.2017.09
Grant Details