Isotopic niche (δ13С and δ15N values) of soil macrofauna in temperate forests. (23rd April 2014)

• Record Type: Journal Article
• Authors: Korobushkin, Daniil I.; Gongalsky, Konstantin B.; Tiunov, Alexei V.
• Is Part Of: Rapid communications in mass spectrometry. Volume 28:Number 11(2014)
• Page Start: 1303
• Page End: 1311
• Publication Date: 2014-04-23
• Subjects: Mass spectrometry -- Periodicals; 543.65
• DOI: 10.1002/rcm.6903
• Languages: English
• ISSNs: 0951-4198

Abstract

<abstract abstract-type="main"> <title> <x xml:space="preserve">Abstract</x> </title> <sec id="rcm6903-sec-0001" sec-type="section"> <title>RATIONALE</title> <p>Stable isotope analysis (SIA) is used widely for reconstructing trophic links of vertebrate and invertebrate animals. Soil macrofauna form a substantial food source for a range of predators including amphibians, reptiles, birds and mammals. SIA‐based estimations of their trophic niches require knowledge on the full range of isotopic signatures of potential preys. Considering the extremely high diversity of soil animals, this information is not easy to obtain.</p> </sec> <sec id="rcm6903-sec-0002" sec-type="section"> <title>METHODS</title> <p>We estimated a typical range of the isotopic signatures of soil macrofauna by compiling published and original data on soil macroinvertebrates in 11 temperate forests. We examined whether the baseline correction (i.e. subtracting δ<sup>13</sup>C or δ<sup>15</sup>N values of local litter) would decrease the between‐site variability in the δ<sup>13</sup>C and δ<sup>15</sup>N values of soil animals. The dataset was subsequently used to estimate the frequency distribution of δ<sup>13</sup>C and δ<sup>15</sup>N values in saprophagous and predatory soil animals.</p> </sec> <sec id="rcm6903-sec-0003" sec-type="section"> <title>RESULTS</title> <p>The baseline correction reduced the between‐site variability in δ<sup>15</sup>N, but not in δ<sup>13</sup>C values of soil animals. Over 95% of the taxa or individuals examined fell into an isotopic space with uncorrected δ<sup>13</sup>С values ranging from −27.9 to −22.5‰, and litter‐normalized δ<sup>15</sup>N values from 0.8 to 9.6‰. Saprophagous and predatory soil animals were on average enriched in <sup>13</sup>C relative to plant litter by 3.5 and 2.7‰, respectively, which is likely to reflect the importance of saprotrophic microorganisms as the main energy source in soil food webs. The difference in δ<sup>15</sup>N values between saprophages and predators averaged 2.8‰, which fits the anticipated trophic enrichment per trophic level.</p> </sec> <sec id="rcm6903-sec-0004" sec-type="section"> <title>CONCLUSIONS</title> <p>Our results indicate that the range of possible δ<sup>15</sup>N values of soil macrofauna in temperate forest ecosystems can roughly be predicted based on the δ<sup>15</sup>N values of plant litter. On the other hand, no site‐specific normalization is usually required when predicting the range of δ<sup>13</sup>C values of soil macroinvertebrates. Copyright © 2014 John Wiley & Sons, Ltd.</p> </sec> </abstract>