Isotopes of carbon

About: Isotopes of carbon is a research topic. Over the lifetime, 3447 publications have been published within this topic receiving 180482 citations. The topic is also known as: Carbon Radioisotope & Carbon Radioisotopes.

Carbon Isotope Discrimination and Photosynthesis

Abstract: We discuss the physical and enzymatic bases of carbone isotope discrimination during photosynthesis, noting how knowledge of discrimination can be used to provide additional insight into photosynthetic metabolism and the environmental influences on that process

Carbon Isotopes in PhotosynthesisFractionation techniques may reveal new aspects of carbon dynamics in plants

Abstract: he efficiency of photosynthesis continues to interest biochemists, biologists, and plant physiologists. Scientists interested in CO2 uptake are concerned about the extent to which the uptake rate is limited by such factors as stomatal diffusion and the chemistry of the CO2 absorption process. The fractionation of carbon isotopes that occurs during photosynthesis is one of the most useful techniques for investigating the efficiency of CO2 uptake. Atmospheric carbon dioxide contains approximately 1.1% of the nonradioactive isotope carbon-13 and 98.9% of carbon-12. During photosynthesis, plants discriminate against C because of small differences in chemical and physical properties imparted by the difference in mass. This discrimination can be used to assign plants to various photosynthetic groups. The isotope fractionation also reflects limitations on photosynthetic efficiency imposed by the various diffusional and chemical components of CO2 uptake. When analyzed in detail, this fractionation provides information .about water use efficiency and indicates that different strategies are needed for improving wateruse efficiency in different kinds of plants. Isotope fractionation in simple physical and chemical processes is well understood and is commonly Current studies include

Stable isotopes in ecology and environmental science

Abstract: Contributors. Abbreviations. Introduction. 1. Stable isotope chemistry and measurement: a primer. Elizabeth W. Sulzman. Introduction. What isotopes are, what makes them distinct. Properties of ecologically useful stable isotopes. Technological advances and current trends in the ecological use of isotopes. Acknowledgments. References. 2. Sources of variation in the stable isotopic composition of plants. John D. Marshall, J. Renee Brooks, and Kate Lajtha. Introduction. Carbon isotopes. Nitrogen isotopes. Hydrogen and oxygen isotopes. Conclusions. References. 3. Natural 15N- and 13C-abundance as indicators of forest nitrogen status and soil carbon dynamics. Charles T. Garten, Jr, Paul J. Hanson, Donald E. Todd, Jr, Bonnie B. Lau, and Deanne J. Brice. Introduction. Significance of 15N-abundance to soil carbon sequestration. Vertical changes in soil 13C-abundance and soil carbon dynamics. Conclusions. Acknowledgments. References. 4. Soil nitrogen isotope composition. R. Dave Evans. Introduction. Sources of variation in soil 15N. Patterns of soil nitrogen isotope composition. Conclusions. References. 5. Isotopic study of the biology of modern and fossil vertebrates. Paul L. Koch. Introduction. Vertebrate tissues in the fossil record. Controls on the isotopic composition of vertebrate tissues. Preservation of biogenic isotope compositions by vertebrate fossils. Paleobiological applications. Conclusions. A post-script on workshops and literature resources. References. 6. Isotopic tracking of migrant wildlife. Keith A. Hobson. Introduction. Basic principles. Marine systems. Terrestrial systems (excluding deuterium). Using deuterium patterns in precipitation. Conclusions. References. 7. Natural abundance of 15N in marine planktonic ecosystems. Joseph P. Montoya. Introduction. Background. Isotopic variation in marine nitrogen. Source delineation and isotope budgets. Animal fractionation and food web processes. Isotopic transients in marine systems. Compound-specific nitrogen isotope analyses. Conclusions. Acknowledgment. References. 8. Stable isotope studies in marine chemoautotrophically based ecosystems: An update. Cindy Lee Van Dover. Introduction. Isotopic tracing of carbon at methane seeps. Whale falls. Hydrothermal vents. Conclusions. References. 9. Stable isotope ratios as tracers in marine food webs: An update. Robert H. Michener and Les Kaufman. Introduction. Methods of assessing food webs. Phytoplankton and particulate organic carbon. Phytoplankton and particulate organic nitrogen. Marine food webs. Stable isotopes in marine conservation biology. Conclusions. Acknowledgments. References. 10. Stable isotope tracing of temporal and spatial variability in organic matter sources to freshwater ecosystems. Jacques C. Finlay and Carol Kendall. Introduction. Overview of river food webs and stable isotope approaches. Stable isotope ratios of organic matter sources in stream ecosystems. C, N, and S isotopic variability and its applications in river ecology. Conclusions. Acknowledgments. References. 11. Stable isotope tracers in watershed hydrology. Kevin J. McGuire and Jeff McDonnell. Introduction. Basic concepts in watershed hydrology. Why are stable isotopes needed?. General concepts in isotope hydrology. Applications of isotope hydrology in watershed and ecosystem studies. Conclusions. Acknowledgments. References. 12. Tracing anthropogenic inputs of nitrogen to ecosystems. Carol Kendall, Emily M. Elliott, and Scott D. Wankel. Introduction. Isotopic compositions of major N sources to ecosystems. Processes affecting the isotopic composition of DIN. Separating mixing of sources from the effects of cycling. Applications to different environmental settings. What sources of agricultural and urban sources of nitrate can be distinguished using isotopes?. Other tools for tracing anthropogenic contaminants. Conclusions. References. 13. Modeling the dynamics of stable-isotope ratios for ecosystem biogeochemistry. William S. Currie. Introduction. Designing consistent model-data linkages and comparisons. Principles and techniques of stable isotope modeling. Conclusions. Acknowledgments. References. 14. Compound-specific stable isotope analysis in ecology and paleoecology. Richard P. Evershed, Ian D. Bull, Lorna T. Corr, Zoe M. Crossman, Bart E. van Dongen, Claire Evans, Susan Jim, Hazel Mottram, Anna J. Mukherjee, and Richard D. Pancost. Introduction. Why use compound-specific stable isotopes?. Analytical considerations in compound-specific stable isotope analysis. Applications of compound-specific stable isotope approaches in ecology and paleoecology. Conclusions. References. Index