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Citation. Kaufmann, G. W. 1971. Behavior and Ecology of the Sora Porzana carolina and Virginia Rail Rallus limicola. Ph.D. Thesis. University of Minnesota. [1350 CC]
Abstract. Summer samples of marsh gases in Minnesota (fresh-water), Louisiana, and Delaware (fresh-water and brackish-water) yielded 50-85% methane, 3-52% "excess nitrogen", 1-15% carbon dioxide, and small amounts or traces of hydrogen, carbon monoxide, propane, hydrogen sulfide, and C4-C7 hydrocarbons. These types of gas flows were found to decrease drastically in winter periods of sampling, and large amounts of air accumulate in some marsh and lake sediments. Carbon dioxide decreases in the winter samples, but carbon monoxide and hydrogen sulfide showed relative increases. Ethane is present in several, and butane in one sample from Minnesota in the fall. There is a drop in "excess nitrogen" (non-air N2) in the winter a compared to summer samples. Specimens of marsh plants were placed in culture flasks with mud from each collecting locality and allowed to culture for several months. In composition, the cultured eases are predominantly methane, carbon dioxide, and "excess nitrogen", Hydrogen, ethane, propane, and hydrogen sulfide are minor components, Carbon monoxide was not detected, in contrast to marsh gases. Phragmites from industrially polluted Delaware Bay evolved many additional hydrocarbons in culture. pH and Eh were monitored for Typha in culture: pH remained near 7 and Eh near -100 mV after stabilization. Carbohydrate analyses of marsh plants indicate xylans exceed cellulose as a major source of methane in these samples; mannose, galactose, and arabinose are also important potential contributors. Delta carbon-13 values of methane from marsh gases sampled are more negative than those from laboratory-cultured source plants, whereas delta deuterium values of methane from marsh oases are less negative than those of cultured source plants.