Decomposition dynamics of sugarcane straw in the central-southern Brazil

作者：Laisa Gouveia Pimentel · 年份：2018 · DOI：10.11606/t.11.2018.tde-21032018-124822 · 被引用次数：1 · 研究领域：Sugarcane Cultivation and Processing、Rice Cultivation and Yield Improvement、Soil Geostatistics and Mapping

The straw decomposition is one of the main factors that should drive the straw removal management decisions for bioenergy production.Therefore, we conducted a field study at two sites in Brazil for two harvesting seasons and over two years, to evaluate the sugarcane straw decomposition under different straw removal rates and characterize straw composition changes over time.The straw rates tested were: no removal (~14 Mg ha -1 of dry mass left on the soil surface), 25% straw removal (~11 Mg ha -1 ), 50% straw removal (~7 Mg ha -1 ), and 75% straw removal (~3.5 Mg ha -1 ).Our results show that straw removal management had no effect on the decomposition in the first year, but the reverse occurred in the second year, which the lowest decomposition was associated with high straw removal rates.The dry mass loss was significantly higher (25%) in the second year than the first year since there was the greater amount of straw left on the soil and by the "legacy effect".The negative exponential model was efficient to predict the C loss over time.The C and N loss was two-and threefold greater in the first years than in the second year of straw deposition, respectively.Overall, the cellulose decreased by 13%, the hemicellulose 7%, and the lignin proportionally enriched by 92% in two years of experiment.In this sense, our findings can be useful to assist sugarcane producers and government to decision-making about better sugarcane straw removal management practices to sustain 2G ethanol e ...