Translocation of surface litter carbon into soil by Collembola

• Published in: Soil biology & biochemistry 2006, Vol.38 (9), p.2655-2664
• Main Authors: Chamberlain, Paul M., McNamara, Niall P., Chaplow, Jacky, Stott, Andrew W., Black, Helaina IJ
• Format: Article
• Language: English
• Subjects: Agronomy. Soil science and plant productions; Alnus glutinosa; Biochemistry and biology; biodegradation; Biological and medical sciences; carbon nitrogen ratio; Chemical, physicochemical, biochemical and biological properties; chlorophyll; Collembola; Decomposition; Folsomia candida; Fundamental and applied biological sciences. Psychology; Physics, chemistry, biochemistry and biology of agricultural and forest soils; plant litter; Plant pigments; PLFA; soil arthropods; soil organic matter; soil respiration; Soil science; soil transport processes; Stable isotopes; Zoology (interactions between soil fauna and agricultural or forest soils)
• ISSN: 0038-0717; 1879-3428
• DOI: 10.1016/j.soilbio.2006.03.021

Soil invertebrates are important in nutrient cycling in soils, but the degree to which mesofauna such as Collembola are responsible for the direct movement of carbon (C) from the litter layer into soil has not yet been ascertained. We used naturally occurring stable C isotopic differences between a C 4 soil and alder leaves (C 3) to examine the effect of the collembolan Folsomia candida on C translocation into soil in laboratory microcosms. Collembolan numbers greatly increased in the presence of alder, but despite large collembolan populations there were no changes in decomposition rate (measured as litter mass loss, cumulative respired CO 2 and alder C:N ratios). Small changes in the δ 13C values of bulk soil organic matter were detected, but could not be assigned to collembolan activity. However, mean δ 13C values of soil microbial phospholipid fatty acids (PLFAs) were significantly lower in the presence of alder and Collembola together, demonstrating that collembolan activities resulted in greater availability of litter-derived C to the soil microbial community. Additionally, the presence of Collembola resulted in the translocation of alder-derived compounds (chlorophyll and its breakdown product pheophytin) into soil, demonstrating that Collembola modify soil organic matter at the molecular level. These results are consistent with deposition of collembolan faeces in underlying soil and demonstrate that despite their small size, Collembola contribute directly to C transport in the litter-soil environment.