The Effect of Nutrient Availability on the Ecological Role of Filamentous Microfungi: Lessons from Elemental Stoichiometry

Abstract

Carbon (C), Nitrogen (N) and Phosphorus (P) are three of the most important elements used to build living beings, and their uptake from the environment is consequently essential for all organisms. Photosynthesis is the process in which plants absorb atmospheric C as they grow and convert it to biomass. However, plants acquire N and P only when these are available in the soil solution, which makes these elements the most limiting nutrients in plant growth and productivity in most ecosystems. When plant residues and roots decompose, the C, N and P they contain is transformed primarily into soil organic matter (SOM) or C and N can release to the atmosphere. Recent interest on the global C, N and P cycles has focused attention on the different proportion of terrestrial C, N and P stored in different ecosystem pools. Cuatro Cienegas represents an exceptional place, since the plants are not the base of the food web, they are the microbial community, that recycle the elements essential for life. In this book we describe how this is an analog of early Earth. Intro; Preface; Contents; Chapter 1: Carbon, Nitrogen, and Phosphorus in Terrestrial Pools: Where Are the Main Nutrients Located in the Grasslands of the Cuatro Ciénegas Basin?; Introduction; Materials and Methods; Study Area; Sampling; Laboratory Analyses; Data Analyses; Results; Nutrients in Above- and Belowground Grass Biomass; Soil Nutrient and Ecosystem Nutrient Contents; Discussion; References; Chapter 2: Terrestrial N Cycling in an Endangered Oasis; N Cycle in Arid Lands; N Fixers and Denitrifiers in Soils with Different Water Availability. N Fixers in Soils with Different Precipitation Regimes: The Case of Soil Crusts of Cold and Hot DesertsInfluence of the Rhizosphere on the Abundance of Microorganisms Involved in the N Cycle; References; Chapter 3: The Effect of Nutrients and N:P Ratio on Microbial Communities: Testing the Growth Rate Hypothesis and Its Extensions in Lagunita Pond (Churince); Introduction; Experiments/Tests; Methods; Results; Interpretations and Conclusions; References; Chapter 4: The Effect of Nutrient Availability on the Ecological Role of Filamentous Microfungi: Lessons from Elemental Stoichiometry. IntroductionMaterials and Methods; Chemical Analyses of Mycelia, Water Samples, and Potato Dextrose Broth; Results and Discussion; Conclusions; References; Chapter 5: Life on a Stoichiometric Knife Edge: Biogeochemical Interactions and Trophic Interactions in Stromatolites in Rio Mesquites; Introduction; Experiments/Studies; Implications/Conclusions; References; Chapter 6: The Sulfur Cycle as the Gear of the "Clock of Life": The Point of Convergence Between Geological and Genomic Data in the Cuatro Cienegas Basin. Oldest Evidence of Life on Earth: Stromatolites, Hydrothermal Vents, and Hot Springs -- What Do They Have in Common?Using Sulfur in Early Life: Molecular and Genomic Evidence; Modern Distribution of Sulfur Metabolism Across the Tree of Life; Integrating the Sulfur Cycle Within the Microbial Mat Model; Capturing the Importance of Global Sulfur Cycle with a Single Value; Conclusions and Remarks; References; Chapter 7: Toward a Comprehensive Understanding of Environmental Perturbations in Microbial Mats from the Cuatro Cienegas Basin by Network Inference. General Overview of CCB Hydrogeology and Its Aquifer OverexploitationThe Churince System: A Scenario for Our Study; Microbial Mats: A Biomarker to Understand Environmental Perturbation; Understanding Microbial Relationships by Network Inference; How Is the Loss of Water Affecting the Microbial Mats Within Churince Lagoon?; Network Community Structure Indicates Overlapping Niches Within Microbial Mats; Conclusions; References; Chapter 8: The Magnetotactic Bacteria of the Churince Lagoon at Cuatro Cienegas Basin; The Iron and Sulfur Cycles.