Soil CO2 efflux and soil carbon balance of a tropical rubber plantation

• Published in: Advances in ecological research Vol. 28; no. 6; pp. 969 - 979
• Main Authors: Satakhun, Duangrat, Gay, Frédéric, Chairungsee, Naruenat, Kasemsap, Poonpipope, Chantuma, Pisamai, Thanisawanyangkura, Sornprach, Thaler, Philippe, Epron, Daniel
• Format: Journal Article
• Language: English
• Published: Tokyo Springer Japan 01.11.2013; Springer; Blackwell Publishing Ltd; Elsevier
• Subjects: Animal and plant ecology; Animal, plant and microbial ecology; autotrophs; Behavioral Sciences; biogeochemical cycles; Biological and medical sciences; Biomass; Biomedical and Life Sciences; carbon; Carbon cycle; Carbon dioxide; Decomposition; Ecology; Evolutionary Biology; Forestry; Fundamental and applied biological sciences. Psychology; General aspects; heterotrophs; income; Land use; Landscape ecology; Life Sciences; mathematical models; Moisture content; organic horizons; Original Article; Partitioning; plant litter; Plant Sciences; Plantations; Respiration; rhizosphere; rhizosphere bacteria; rhizosphere fungi; Root biomass; roots; Rubber; Rubber plantation; Rubber trees; Seasonal variation; Seasonal variations; Soil respiration; Soil temperature; Soil water; soil water content; soil-atmosphere interactions; Soils; Synecology; Thailand; trees; trenching; tropics; Water content; Zoology; Thailand; Root biomass; Partitioning; Soil respiration; Seasonal variation; Rubber plantation; Soils; Root; Carbon dioxide; Biomass; Rubber; Respiration; Carbon balance
• ISSN: 0912-3814; 0065-2504; 1440-1703; 2163-582X
• DOI: 10.1007/s11284-013-1079-0

Natural rubber is a valuable source of income in many tropical countries and rubber trees are increasingly planted in tropical areas, where they contribute to land-use changes that impact the global carbon cycle. However, little is known about the carbon balance of these plantations. We studied the soil carbon balance of a 15-year-old rubber plantation in Thailand and we specifically explored the seasonal dynamic of soil CO 2 efflux ( F S ) in relation to seasonal changes in soil water content ( W S ) and soil temperature ( T S ), assessed the partitioning of F S between autotrophic ( R A ) and heterotrophic ( R H ) sources in a root trenching experiment and estimated the contribution of aboveground and belowground carbon inputs to the soil carbon budget. A multiplicative model combining both T S and W S explained 58 % of the seasonal variation of F S . Annual soil CO 2 efflux averaged 1.88 kg C m −2  year −1 between May 2009 and April 2011 and R A and R H accounted for respectively 63 and 37 % of F S , after corrections of F S measured on trenched plots for root decomposition and for difference in soil water content. The 4-year average annual aboveground litterfall was 0.53 kg C m −2  year −1 while a conservative estimate of belowground carbon input into the soil was much lower (0.17 kg C m −2  year −1 ). Our results highlighted that belowground processes (root and rhizomicrobial respiration and the heterotrophic respiration related to belowground carbon input into the soil) have a larger contribution to soil CO 2 efflux (72 %) than aboveground litter decomposition.