Organic matter stable isotopes

The quantification of gross root production, rhizodeposition, microbial assimilation, and the production of organic materials in soil has made increasing progress ever since stable ( C) and radioactive ( C) carbon isotopes have been used (see Chap. 12). Measurements of soil organic matter dynamics without these isotopes are difficult due to the large amount present as compared to the smaller rates of input. 

Macko A, Estep MLF (1984) Microbial alteration of stable nitrogen and carbon isotopic compositions of organic matter. Org Geochem 6 787-790... 

Bostrom B, Comstedt D, Ekblad A (2008) Can isotopic fractionation during respiration explain the 13C enriched sporocarps of ectomycorrhizal and saprotrophic fungi New Phytol 177 1012-1019 Boutton TW (1996) Stable carbon isotopes ratios of soil organic matter and their use as indicators of vegetation and climate change. In Boutton TW, Yamasaki S (eds) Mass spectrometry of soils. Marcel Dekker Inc., New York, pp 47-82... 

Benner, R., B. Biddanda, B. Black, and M. McCarthy. 1997. Abundance, distribution, and stable carbon and nitrogen isotopic compositions of marine organic matter isolated by tangential-flow ultrafiltration. Marine Chemistry 57 243—263. 

The implications of HOP for quality of organic matter, including quality of DOM, are similar to those of HON (discussion below) as the P content of organic material is often cited as an important determinant of organic matter quality (Sterner, 1995). HON has additional implications for stable isotope research, however, that do not apply to HOP. 

Pessenda, L. C. R., Gouveia, S. E. M., Aravena, R., Gomez, B. M., Boulet, R., and Ribeiro, A. S. (1998). 14C dating and stable carbon isotopes of soil organic matter in forest savanna boundary areas in the southern Brazilian Amazon region. Radiocarbon 40,1013-1022. 

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