Download or read book Isotopic Composition of Stable Carbon and Carbon Dioxide Concentration of Atmosphere in Streambeds Near Tombstone Arizona written by Jeffrey Scott Riddle and published by . This book was released on 1984 with total page 136 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Isotopic Composition of Soil Carbon Dioxide and Groundwater in an Irrigated Cotton Field San Joaquin Valley California written by Rochelle Bell and published by . This book was released on 1988 with total page 300 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Masters Abstracts written by and published by . This book was released on 1985 with total page 706 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Masters Abstracts International written by and published by . This book was released on 1985 with total page 1632 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Variations in Concentrations and Carbon Stable Isotope Values of Atmospheric Carbon Dioxide in the Dallas Metropolitan Area Texas written by Shannon Clark and published by . This book was released on 2000 with total page 272 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Isotopic Composition of Soil Carbon Dioxide in the Tucson Basin written by Carmen Bajos Parada and published by . This book was released on 1981 with total page 170 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Temporal Variability in the Concentration and Stable Carbon Isotope Composition of Dissolved Inorganic and Organic Carbon in Two Montana USA Rivers written by Stephen R. Parker and published by . This book was released on 2009 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Interpretation of Chemical and Isotopic Data from Boreholes in the Unsaturated Zone at Yucca Mountain Nevada written by In Che Yang and published by . This book was released on 1996 with total page 64 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Stable Carbon and Nitrogen Isotopic Composition of the Sedimentary Organic Matter from the Central Gulf of Mexico written by Liesl C. Rhodes and published by . This book was released on 1990 with total page 16 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Stable Isotopes as a Tool to Characterize Carbon Cycling and Develop Hydrologic Budgets in Mantled Karst Settings written by Katherine J. Knierim and published by . This book was released on 2015 with total page 536 pages. Available in PDF, EPUB and Kindle. Book excerpt: Isotopes of water (delta2H/delta 18O), carbon dioxide (delta13C-CO2), and dissolved inorganic carbon (delta13C-DIC) were used to explore water quality, trace carbon cycling, and quantify recharge sources through mantled karst and into Blowing Spring Cave (BSC). Of the possible sources of contamination in the BSC recharge area, septic-tank effluent was hypothesized to degrade water quality at the spring outlet of BSC because of the dominance of septic tanks for waste treatment, unsuitable topography and soil for septic-tank absorption fields, increased nitrate and chloride concentrations concomitant with increased urbanization, and increased Escherichia coli with discharge. Carbon cycling between the soil and BSC was constrained by (1) mixing of gaseous soil CO2 and surface-atmosphere CO2 to produce cave-air CO2 concentrations and isotopic compositions, (2) kinetic degassing of cave drip-water, causing greater delta13 C-DIC values than expected during equilibrium carbon isotopic fractionation between CO2 and DIC, and (3) exchange of soil-gas CO2 with groundwater prior to entering the cave, providing evidence that cave-stream water was characterized by open-system conditions with regards to soil CO 2. This conceptual model of carbon cycling in BSC---where cave-air CO2 is partially sourced from soil CO2 and aqueous and gaseous carbon reservoirs within the cave are relatively decoupled---provides evidence that the majority of soil CO2 enters the cave as a gas. A three-component hydrograph separation was completed to quantify precipitation (QR), soil water (QS), and bedrock-matrix water (Q B) contributions to BSC during storm events. Antecedent moisture conditions changed throughout the sampling period because as rainfall and base-flow discharge increased, delta18O values of cave water increased, chloride concentration in soil and cave water decreased, and DIC in cave water decreased. Combined QS and QB accounted for 36 to 119% of total discharge during storm events, depending on time after the onset of precipitation and antecedent moisture conditions. QR was greatest during a wet-season storm and rapid dilution of major cations and anions occurred with increased discharge. In contrast, a dry-season storm had the lowest QR and anion concentration peaked with maximum QS. Even during extremely dry periods, pre-event water stored in the unsaturated zone can contribute to groundwater flow during storms.

Download or read book Carbon Isotope Data in Core V19 30 Confirm Reduced Carbon Dioxide Concentration in the Ice Age Atmosphere written by and published by . This book was released on 1983 with total page 4 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Carbon Isotope Analysis of the Sources and Mechanisms of CO2 Input and Removal from Central Texas Cave Systems written by Ashley Elizabeth Quinn and published by . This book was released on 2010 with total page 108 pages. Available in PDF, EPUB and Kindle. Book excerpt: Speleothem calcite growth rate is a commonly used paleoclimate proxy. Seasonal variations in cave CO2 concentration (P[subscript CO2]) are known to control speleothem growth. Thus, it is important to understand the mechanisms of CO2 input and removal from cave systems in order to better use speleothem calcite growth rate as a proxy. To this end, spatial and temporal variations in the atmosphere of several central Texas caves were studied over the course of a year. The stable isotope composition of the sources of CO2 in cave air were determined by measuring the [delta]13C values of cave-air CO2 samples collected from specific sites within the caves. Cave-air P[subscript CO2] consistently increased and [delta]13C values consistently decreased with distance from the cave entrance. The values along these spatial transects vary seasonally towards higher [delta]13C values and lower P[subscript CO2] in the winter months (October-March). The linear relationship between [delta]13C and 1/ CO2 suggests that CO2 in the cave atmosphere is a mixture between atmospheric air (~380ppm, -8% [delta]13C, V-PDB) and a cave-end-member with low [delta]13C and high P[subscript CO2]. The concentrations and [delta]13C values of cave-air CO2 were used to find the [delta]13C value of respired CO2 ([delta]13C[subscript r]) by correcting for atmospheric mixing and diffusion in the soil. The [delta]13C value of respired CO2 is generally higher in the summer and lower in the winter. The seasonal- and regionally consistent variations in P[subscript CO2] and the [delta]13C value of cave-air CO2 support density-driven ventilation controlled by seasonal surface temperature changes as the major influence on cave-air CO2. The calculated [delta]13C values suggest that C3 organic material is the primary source of cave-air CO2 and that seasonal variation in the magnitude of photosynthetic discrimination and/or seasonal changes in the relative productivity of C3 vs. C4 vegetation influence the [delta]13C value of CO2 entering the cave.

Download or read book A study of stable carbon isotope ratios in atmospheric carbon dioxide written by Fredrick Brunell (George) and published by . This book was released on 1970 with total page 82 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book The Stable Isotopic Composition of Dissolved Inorganic Carbon Delta13CDIC and Anthropogenic CO2 in the Sub Polar North Atlantic written by Florence Mahalia Greatrix and published by . This book was released on 2015 with total page 56 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Stable Isotopic Composition of Total Organic Carbon in Bottom Sediments of Lake Baikal as a Proxy for Paleoclimatology written by Alexander A. Prokopenko and published by . This book was released on 1997 with total page 558 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Stable nitrogen and carbon isotopic composition of seston and sediment in two Adirondack lakes written by J.S. Owen and published by . This book was released on 1999 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Hydrologic Mediation of the Spatial and Temporal Variability of the Soil Carbon Dioxide Stable Isotopic Composition of a Subalpine Watershed written by Theresa Marie E. Lorenzo and published by . This book was released on 2015 with total page 81 pages. Available in PDF, EPUB and Kindle. Book excerpt: