Emission of CO2 and soil microbial activity in sugarcane management systems

Abstract

Because of the great importance of sugarcane in the Brazilian agricultural sector, this study was developed in order to evaluate the soil CO 2 flux and the soil microbial activity in the systems of burned sugarcane and green sugarcane. For this end, three areas were evaluated with different histories of sugarcane management: (1) burned sugarcane BS); (2) green sugarcane for 5 years (GS-5); (3) green sugarcane for 10 years (GS-10), considering that both areas of green sugarcane were converted from a scenario of prior burning before harvest. The soil CO 2 flux (FCO 2 ), basal respiration (BR), carbon of the microbial biomass (CMB), metabolic quotient (qCO 2 ) and microbial quotient (qMIC) were evaluated in 30 points in a 100 × 100 m sampling grid, amounting to 1 ha. The results indicated higher FCO 2 and CBM in the GS-10 area, and lower in the BS area, whose CO 2 emission and microbial activity were higher in summer. The metabolic and microbial quotients showed a greater balance of the soil microbial activity in the area of green sugarcane for 10 years, fostered mainly by the higher amount of mulch on the soil.

Soil Greenhouse Gases: Relations to Soil Attributes in a Sugarcane Production Area

“…Infield F CO2 presented a mean value of 1.19 µmol CO 2 m -2 s -1 , with a minimum of 0.50 µmol CO 2 m -2 s -1 , a maximum of 2.29 µmol CO 2 m -2 s -1 , and a CV of 31.68% (Table 1). These rates are similar to those observed in experiments conducted previously in the same geographic region with sugarcane crops (Brito et al, 2010;Panosso et al, 2011Panosso et al, , 2012Corradi et al, 2013;Bicalho et al, 2014;Tavares et al, 2015). Variations in F CO2 observed in these studies, even performed in areas of the same region, are related to changes in soil attributes for each area, such as soil temperature, soil moisture, soil organic matter, microbial activity, pH, the C/N ratio, phosphorus content, soil bulk density, and soil porosity (Kemmitt et al, 2008;Ngao et al, 2012;Oyonarte et al, 2012;Teixeira et al, 2013a;Karhu et al, 2014;Moitinho et al, 2015).…”

“…The large amount of crop residue left on the soil surface after harvest in mechanically harvested sugarcane areas have tremendous impact on production processes and biogeochemical cycling of carbon and nitrogen, affecting soil organic matter dynamics, and consequently, GHG emissions (Cerri et al, 2013). In addition to influencing carbon and nitrogen cycles, environmental conditions and soil management practices adopted during sugarcane crop cultivation may result in changes in soil physical, chemical, and biological attributes, directly affecting microbial activity and thus the production of CO 2 , CH 4 , and N 2 O and their exchanges between soil and the atmosphere (Blair, 2000;Sartori et al, 2006;Cerri et al, 2007Cerri et al, , 2013Denmead et al, 2010;Allaire et al, 2012;Ball, 2013;Signor and Cerri, 2013;Signor et al, 2014;Tavares et al, 2015).…”

Decomposition of the Remaining Straw During Soybean Growing in the Midwestern Paraná, Brazil

“…The equation of the remaining straw decomposition (Tables 3 and 4) allows analyzing the interaction of the material with the environment and defining strategies for soil cover management. In tropical and subtropical regions, the remaining straw act protecting the soil surface, softening the temperature variation of the soil, reducing the evapotranspiration, keeping moisture in the surface zones, providing nutrients to the crops with mineralization of organic matter, and acting in the stabilization of soil aggregates (Torres et al, 2008;Tavares et al, 2015;Bueno e Rodrigues, 2019;Bonetti e Fink, 2020). The parameters of the regression equations and half-life of autumn/winter residues (2020) in soybean (2020/2021) are presented in Table 4.…”

Traffic Control With Autopilot as an Alternative to Decrease Soil Compaction in Sugarcane Areas

“…This traffic of machines tends to increase in areas cultivated with sugarcane. Due to this, developing technologies to determine the impacts from these practices on the physical soil properties is required (Tavares et al, 2015). In this context, controlling the traffic of machines has become a promising alternative to minimize the compaction problem (Kamimura, et al, 2009).…”