2 items with the tag “nitrogen

  • Stoichiometry of Life - Task 1 - Laboratory Studies in Biological Stoichiometry
    NAI 2013 Arizona State University Annual Report

    This project component involves a set of studies of microorganisms with which we are trying to better understand how living things use chemical elements (nitrogen, phosphorus, iron, etc.) and how they cope, in a physiological sense, with shortages of such elements. For example, how does the “elemental recipe of life” change when an organism is starved for phosphorus or nitrogen or iron? Is this change similar for different species of microorganisms? Are the changes the same if the organism is limited by a different key nutrient? Furthermore, how does an organism shift its patterns of gene expression when it is starved by various nutrients? This will help in interpreting studies of gene expression in natural environments.

    ROADMAP OBJECTIVES: 5.2 5.3 6.1 6.2
  • Stoichiometry of Life, Task 2b: Field Studies - Cuatro Cienegas
    NAI 2013 Arizona State University Annual Report

    Cuatro Cienegas is a unique biological preserve in México (state of Coahuila) in which there is striking microbial diversity, potentially related to extreme scarcity of phosphorus. We aim to understand this relationship via field sampling of biological and chemical characteristics and a series of enclosure and whole-pond fertilization experiments. We performed two studies to evaluate ecological impacts of nitrogen and/or phosphorus fertilization in a P-deficient and hyperdiverse shallow pond in the valley of Cuatro Cienegas, Mexico.

    ROADMAP OBJECTIVES: 5.1 5.2 5.3 6.1 6.2