Joseph C. von Fischer, Larry L. Tieszen, Carbon Isotope Characterization of Vegetation and Soil Organic Matter in Subtropical Forests in Luquillo, Puerto Rico, Biotropica, Vol. 27, No. 2 (Jun., 1995), pp. 138-148
No takes yet. Share an insight, caveat, or question.
Fischer et al. (1995) studied this question.