Chapters authored
Multi-Analytical Interactions in Support of Sugarcane Agroecosystems Sustainability in Tropical Soils
The risks of sugarcane management on soil microbes and their relationships with soil physicochemical factors and biogeochemical processes have not been described from an integrated perspective for different agronomic practices. Here, we provide a platform for multi-analytical interactions between ecologists analyzing the soil microbes at multiple ecological levels and geoscientists measuring the release of greenhouse gases and the physicochemical soil factors including labile fractions from soil organic matter in tropical sugarcane management systems. We compile the benefits and risks of nutrient management and soil amendments as well as of crop residue and harvest management in sugarcane soils on belowground microbial life and biogeochemical processes mediated by soil microbial communities, and we demonstrate that the massive planting of the crop brings environmental risks that include a potential impact on tropical soil ecosystem sustainability. We emphasize that soil management and harvest management are critical for supporting the sustainable development of biofuel production in tropical areas.
Part of the book: Sugarcane
Methane, Microbes and Models in Amazonian Floodplains: State of the Art and Perspectives
Amazon floodplain ecosystems include open water and intermittent flood forest and agricultural systems with different water types. They are a significant natural source of methane (CH4) in the tropics. When soils are flooded and become anoxic, CH4 is produced by methanogenesis, while microbially mediated aerobic and anaerobic oxidation of CH4 serves as the primary biological sink of this greenhouse gas. Measurements of rates and controls on CH4 production and emission in the Amazon basin mainly come from studies on individual wetlands and floodplain lakes. Similarly, microbial communities in those Amazon floodplain habitats have been studied on individual lakes based on sequence-specific DNA analysis. Existing biogeochemical ecosystem models of CH4 from the Amazon floodplains focus on soil properties or involve factors such as pH, redox potentials, or substrates. None of these models incorporate appropriate seasonal inundation; neither the microbiota does it as a component. In this sense, our chapter will highlight how the important efforts already contributed to understand the CH4 emission and its connections with abiotic and biotic factors in Amazon floodplains, as well as emphasize the need of encouraging cooperation and exchange of experience between research teams by using different approaches and scientific methods.
Part of the book: Changing Ecosystems and Their Services