Cover crop rotations in no-till system: short-term CO2 emissions and soybean yield

Autor(es)

João Paulo Gonsiorkiewicz Rigon ; Juliano Carlos Calonego ; Ciro Antonio Rosolem ; Newton La Scala Jr.

• Tipo de documento: Artigo Científico
• Fonte: Scientia Agricola; v. 75, n. 1, p. -, Jan. 2018.

Resumo

ABSTRACT: In addition to improving sustainability in cropping systems, the use of a spring and winter crop rotation system may be a viable option for mitigating soil CO2 emissions (ECO2). This study aimed to determine short-term ECO2 as affected by crop rotations and soil management over one soybean cycle in two no-till experiments, and to assess the soybean yields with the lowest ECO2. Two experiments were carried out in fall-winter as follows: i) triticale and sunflower were grown in Typic Rhodudalf (TR), and ii) ruzigrass, grain sorghum, and ruzigrass + grain sorghum were grown in Rhodic Hapludox (RH). In the spring, pearl millet, sunn hemp, and forage sorghum were grown in both experiments. In addition, in TR a fallow treatment was also applied in the spring. Soybean was grown every year in the summer, and ECO2 were recorded during the growing period. The average ECO2 was 0.58 and 0.84 g m2 h–1 with accumulated ECO2 of 5,268 and 7,813 kg ha–1 C-CO2 in TR and RH, respectively. Sunn hemp, when compared to pearl millet, resulted in lower ECO2 by up to 12 % and an increase in soybean yield of 9% in TR. In RH, under the winter crop Ruzigrazz+Sorghum, ECO2 were lower by 17%, although with the same soybean yield. Soil moisture and N content of crop residues are the main drivers of ECO2 and soil clay content seems to play an important role in ECO2 that is worthy of further studies. In conclusion, sunn hemp in crop rotation may be utilized to mitigate ECO2 and improve soybean yield. (AU)

• Processo FAPESP: 09/16060-7 - Matéria orgânica e emissão de gases de efeito estufa em sistemas de produção em semeadura direta
• Beneficiário: Juliano Carlos Calonego
• Linha de fomento: Bolsas no Brasil - Pós-Doutorado
• Processo FAPESP: 11/15361-3 - Emissão de gases de efeito estufa em áreas com diferentes rotações de culturas em sistema semeadura direta
• Beneficiário: João Paulo Gonsiorkiewicz Rigon
• Linha de fomento: Bolsas no Brasil - Mestrado