Here you can take a look at how some researchers are using stable isotope mass spectrometry in their research.

Billings, S.A., 2006. Soil organic matter dynamics and land use change at a grassland/forest ecotone. Soil Biology and Biochemistry 38 (2006) 2934-2943

Billings, S.A., D. D. Richter, 2006. Changes in stable isotopic signatures of soil nitrogen and carbon during 40 years of forest development. Oecologia (2006) 148: 325-333

Billings, S.A., Schaeffer, S.M., Evans, R.D., 2002. Trace losses and N mineralization in Mojave Desert soils exposed to Elevated CO₂. Soil Biology & Biochemistry 34, 1777- 1784

Billings, S.A., Schaeffer, S.M., Zitzer, S., Charlet, T., Smith, S.D., Evans, R.D., 2002. Alterations of nitrogen dynamics under elevated carbon dioxide in an intact Mojave Desert ecosystem: evidence from Nitrogen-15 natural abundance. Oecologia 131:463-467

Billings, S.A., Ziegler, S.E., 2005. Linking microbial activity and soil organic matter transformations in forest soils under elevated CO₂. Global Change Biology 11, 1-10

Brisco, S., Ziegler, S., 2004. Effcts of solar radiation on the utilization of dissolved organic matter (DOM) from two headwater syatems. Aquatic Microbial Ecology Vol. 37: 197-208

Farina, J. M., S. Salazar, K. P. Wallem, J. D. Witman, J. C. Ellis. 2003. Nutrient exchanges between marine and terrestrial ecosystems: the case of the Galapagos sea lion Zalophus wollebaecki. Journal of Animal Ecology. 2003. 72, 873-887.

Hsu, C.C., T.C. Lin, W.L. Chiou, S.H. Lin, K.C. Lin, C.E. Martin, 2006. Canopy CO₂ concentrations and Crassulacean acid metabolism in Hoya carnosa in a subtropical rain forest in Taiwan: consideration of CO₂ availability and the evolution of CAM in epiphytes. Photosynthetica 44(1): 130-135, 2006

Martin, Shannon L., Ryan Davis, Piero Protti, Teng-Chiu Lin, Shin-Hwei Lin, Craig E. Martin, 2005. The occurrence of Crassulacean Acid Metabolism in epiphytic ferns, with an emphasis on the Vittariaceae. Int. J. Plant Sci. 166(4):623-630. 2005.

McCue, Marshall D., 2007. Western Diamondback Rattlesnakes Demonstrate Physiological and Biochemical Strategies for Tolerating Prolonged Starvation. Physiological and Biochemical Zoology 80(1):25-34

Reich, A., Ewel, J.J., Nadkarni, N.M., Dawson, T., Evans, R.D., 2003. Nitrogen isotope ratios shift with plant size in tropical bromeliads. Oecologia 137: 587-590

Sagers, C.L., F.L. Goggin, 2006. Isotopic enrichment in a phloem-feeding insect: influences of nutrient and water availability. Oecologia (2007) 151:464-472

Sagers, C.L., Ginger, S.M., Evans, R.D., 2000. Carbon and nitrogen isotopes trace nutrient exchange in an ant-plant mutualism. Oecologia 123: 582-586

Schaeffer, S.M., Billings, S.A., Evans, R.D., 2003. Responses of soil nitrogen dynamics in a Mojave Desert ecosystem to manipulations in soil carbon and nitrogen availability. Oecologia 134: 547-553

Straight, W.H., Karr, J.D., Cox, J.E., Barrick, R.E., 2004. Stable oxygen isotopes from theropod dinosaur tooth enamel:interlaboratory comparison of results and analytical interference by refernce standards. Rapid Communications in Mass Spectrometery 18: 2897-2903

Trimble, S.T., Sagers, C.L., 2004. Differential host use in two highly specialized ant-plant associations: evidence from stable isotopes. Oecologia 138:74-82

Ziegler, S.E., Brisco, S.L., 2004. Relationships between the isotopic composition of dissolved organic carbon and its bioavailability in contrasting Ozark streams. Hydrobiologia 513: 153-169

Ziegler, S.E., Fogel, M.L., 2003. Seasonal and diet relationships between the isotopic comositions of dissolved and particulate organic matter in freshwater ecosystems. Biogeochemistry 64: 25-52

Ziegler, S.E., White, P.M., Wolf, D.C., Thoma, G.J., 2005. Tracking the fate and recycling of C-Labeled glucose in soil. Soil Science Vol. 170, No. 10 767-778