NITKOGEIV cycle is disturbed by human activities, while some nitrogenous compounds are harmful to hu- man health. When large amounts of nitrogenous compounds such as protein, urea, etc., which can bedegraded to NH<...NITKOGEIV cycle is disturbed by human activities, while some nitrogenous compounds are harmful to hu- man health. When large amounts of nitrogenous compounds such as protein, urea, etc., which can bedegraded to NH<sub>4</sub><sup>+</sup> by microbes, enter waters, some of them are assimilated to biomass, but most are stillin waters. In the presence of oxygen, NH<sub>4</sub><sup>+</sup> are oxidized to NC<sub>2</sub><sup>-</sup> and NO<sub>3</sub><sup>-</sup> by autotrophic bacteria. Inanoxic phase, denitrifiers such as Pseudomonas Migula, Achromobacteaceae, Bacillus and Micrococcus,etc. will proceed denitrification, utilizing N0<sub>3</sub><sup>-</sup> as the terminal electron acceptor instead of O<sub>2</sub> in the respiratory chain. Because bacteria denitrification, involving four steps from NO<sub>3</sub><sup>-</sup> to NO<sub>2</sub><sup>-</sup>, NO, N<sub>2</sub>O andN<sub>2</sub>, in fact, is an enzymatically catalytic process, changes of environmental factors such as展开更多
为揭示青藏高原纳木错湖水化学离子的时空变化特征、来源以及主要控制因子,于2006～2010年连续定点(30°47.27'N,90°58.53'E,4 718 m a.s.l.)采集近岸表层湖水样品;于2009年8月采集湖心区剖面样品;于2010年10月采集湖...为揭示青藏高原纳木错湖水化学离子的时空变化特征、来源以及主要控制因子,于2006～2010年连续定点(30°47.27'N,90°58.53'E,4 718 m a.s.l.)采集近岸表层湖水样品;于2009年8月采集湖心区剖面样品;于2010年10月采集湖心区剖面样品及表层湖水样品;对其主要化学离子进行分析.结果表明,纳木错湖水中主要阳离子为Na+,主要阴离子为HCO3-.绝大多数离子浓度在季风期较高(6～9月),而非季风期尤其是封冻期(1～4月)偏低;Ca2+浓度的变化则相反,即封冻期较高,而非封冻期较低且变化较小.对垂直剖面湖水分析表明,在湖水垂直结构稳定的非季风期(如10月),除Ca2+浓度随深度无显著变化外,其他离子浓度随深度增加而增大.纳木错湖水主要离子来源于入湖河水的贡献;影响离子时空变化的因素包括蒸发、降水、pH值等,其中蒸发是最主要的影响因素,它造成湖水Na+浓度不断升高而Ca2+浓度降低.展开更多
文摘NITKOGEIV cycle is disturbed by human activities, while some nitrogenous compounds are harmful to hu- man health. When large amounts of nitrogenous compounds such as protein, urea, etc., which can bedegraded to NH<sub>4</sub><sup>+</sup> by microbes, enter waters, some of them are assimilated to biomass, but most are stillin waters. In the presence of oxygen, NH<sub>4</sub><sup>+</sup> are oxidized to NC<sub>2</sub><sup>-</sup> and NO<sub>3</sub><sup>-</sup> by autotrophic bacteria. Inanoxic phase, denitrifiers such as Pseudomonas Migula, Achromobacteaceae, Bacillus and Micrococcus,etc. will proceed denitrification, utilizing N0<sub>3</sub><sup>-</sup> as the terminal electron acceptor instead of O<sub>2</sub> in the respiratory chain. Because bacteria denitrification, involving four steps from NO<sub>3</sub><sup>-</sup> to NO<sub>2</sub><sup>-</sup>, NO, N<sub>2</sub>O andN<sub>2</sub>, in fact, is an enzymatically catalytic process, changes of environmental factors such as
文摘为揭示青藏高原纳木错湖水化学离子的时空变化特征、来源以及主要控制因子,于2006～2010年连续定点(30°47.27'N,90°58.53'E,4 718 m a.s.l.)采集近岸表层湖水样品;于2009年8月采集湖心区剖面样品;于2010年10月采集湖心区剖面样品及表层湖水样品;对其主要化学离子进行分析.结果表明,纳木错湖水中主要阳离子为Na+,主要阴离子为HCO3-.绝大多数离子浓度在季风期较高(6～9月),而非季风期尤其是封冻期(1～4月)偏低;Ca2+浓度的变化则相反,即封冻期较高,而非封冻期较低且变化较小.对垂直剖面湖水分析表明,在湖水垂直结构稳定的非季风期(如10月),除Ca2+浓度随深度无显著变化外,其他离子浓度随深度增加而增大.纳木错湖水主要离子来源于入湖河水的贡献;影响离子时空变化的因素包括蒸发、降水、pH值等,其中蒸发是最主要的影响因素,它造成湖水Na+浓度不断升高而Ca2+浓度降低.
