Belowground Carbon Budget and Nutrient Uptake of Temperate Forest Species in Response to Elevated Carbon Dioxide and Temperature
A large proportion of carbon in forest ecosystems is lost from belowground through root respiration. Maintenance respiration of attached fine roots was measured on mature loblolly pine and sweetgum (Liquidambar styraciflua ) growing in atmospheric CO2 elevated by 200 mu1 1 -1 above ambient. Fine root maintenance respiration on a mass basis was significantly lower in the elevated CO2 treatment for loblolly pine, but was not significantly different for sweetgum. Annual growth respiration was significantly higher in the elevated CO2 treatment for loblolly pine because of significantly greater construction respiration and fine root production. Maintenance respiration was 98% of total respiration leaving a small proportion of energy for growth and nitrogen-uptake. The reduction in annual total fine root respiration of loblolly pine in elevated CO 2 will result in more carbon being stored belowground.
University of Illinois - Urbana-Champaign
Networked Digital Library of Theses and Dissertations
University of Illinois at Urbana-Champaign