CO2 fertilization does not affect biomass production and nutritive value of a C-4 tropical grass in short timeframe

Autor(es)

Abdalla Filho, Adibe Luiz ^[1] ; Tavares Lima, Paulo de Mello ^[1] ; Sakita, Gabriel Zanuto ^[1] ; Dias e Silva, Tairon Pannunzio ^[1] ; da Costa, Wilian dos Santos ^[1] ; Ghini, Raquel ^[2] ; Abdalla, Adibe Luiz ^[1] ; Piccolo, Marisa de Cassia ^[1]

Afiliação do(s) autor(es)

^[1] Univ Sao Paulo, Ctr Energia Nucl Agr, Piracicaba - Brazil

^[2] Embrapa Meio Ambiente, Jaguariuna - Brazil

• Tipo de documento: Artigo Científico
• Fonte: GRASS AND FORAGE SCIENCE; v. 74, n. 4 AUG 2019.
• Citações Web of Science: 1

Resumo

Increased atmospheric carbon dioxide (CO2) is a consequence of recent anthropogenic environmental changes, and few studies have evaluated its effects on tropical grasses used in Brazilian pastures, the main feed source for major part of ruminant livestock. This study evaluated forage production, chemical composition, in vitro total gas production and organic matter degradability of Brachiaria brizantha under contrasting CO2 atmospheric conditions in a free air carbon dioxide enrichment (FACE) facility. The forage plants were sown in each of the 12 octagonal rings of the FACE facility: six under ambient atmospheric CO2 concentration of approximately 390 mu mol/mol, hereafter referred to as control (CON) plots, and other six rings enriched with pure CO2 flux to achieve a target CO2 concentration of 550 mu mol/mol, hereafter called elevated CO2 (eCO(2)) plots. Soil samples were collected to determine carbon and nitrogen concentrations. After seventy days of sowing, a standardization cutting was performed and then at regular intervals of 21 days the forage was harvested (ten harvest dates) and forwarded to laboratorial analyses. Forage above-ground biomass production (dry matter (DM): 6,143 vs. 6,554 kg/ha), as well as morphological characteristics (leaves: 71% vs. 68%; stem: 28% vs. 31%), chemical composition (crude protein: 162.9 vs. 161.8; neutral detergent fibre: 663.8 vs. 664.3; acid detergent fibre: 369.5 vs. 381; lignin: 60.1 vs. 64.1 g/kg DM; total C: 45.9 vs. 45.9; total N: 2.8 vs. 2.8; total S: 0.2% vs. 0.2%), organic matter in vitro degradability (573.5 vs. 585.3 g/kg), methane (5.7 vs. 4.3 ml/g DM) and total gas (128.3 vs. 94.5 ml/g DM) production did not differ significantly between CON and eCO(2) treatments (p > .05). The results indicated that at least under short-term enrichment, B. brizantha was not affected by eCO(2). (AU)

• Processo FAPESP: 15/14699-1 - Quantificação e caracterização da biomassa produzida em condições de simulação de aumento da concentração de CO2 atmosférico no sistema agropastoril
• Beneficiário: Adibe Luiz Abdalla Filho
• Modalidade de apoio: Bolsas no Brasil - Doutorado