Integrated farming systems influence soil organic matter dynamics in southeastern Brazil

Author(s):Show less -

Bieluczyk, Wanderlei ^[1] ; Piccolo, Marisa de Cassia ^[1] ; Pereira, Marcos Gervasio ^[2] ; de Moraes, Moacir Tuzzin ^[3] ; Soltangheisi, Amin ^{[4, 5]} ; de Campos Bernardi, Alberto Carlos ^[6] ; Macedo Pezzopane, Jose Ricardo ^[6] ; Anchao Oliveira, Patricia Perondi ^[6] ; Moreira, Marcelo Zacharias ^[6] ; de Camargo, Plinio Barbosa ^[5] ; dos Santos Dias, Carlos Tadeu ^[7] ; Batista, Itaynara ^[8] ; Cherubin, Mauricio Roberto ^[9]

Affiliation

^[1] Univ Sao Paulo, Ctr Nucl Energy Agr, Nutrient Cycling Lab, 303 Centenario Ave, BR-13416000 Piracicaba, SP - Brazil

^[2] Univ Fed Rural Rio de Janeiro, Dept Soils, BR 465 Km 7, BR-23897000 Seropedica, RJ - Brazil

^[3] Univ Tecnol Fed Parana, Dept Agron Sci, Campus Francisco Beltrao, POB 135, BR-85601970 Francisco Beltrao, PR - Brazil

^[4] Univ Lancaster, Lancaster Environm Ctr, Lancaster - England

^[5] Univ Sao Paulo, Ctr Nucl Energy Agr, Isotop Ecol Lab, 303 Centenario Ave, BR-13416000 Piracicaba, SP - Brazil

^[6] Embrapa Southeast Livestoc, Brazilian Agr Res Corp, POB 339, BR-13560970 Sao Carlos, SP - Brazil

^[7] Univ Sao Paulo, Luiz de Queiroz Coll Agr, Dept Exact Sci, 11 Padua Dias Ave, BR-13418900 Piracicaba, SP - Brazil

^[8] Fed Fluminense Univ, Dept Geog, 9 Miguel Frias St, BR-24220900 Niteroi, RJ - Brazil

^[9] Univ Sao Paulo, Luiz de Queiroz Coll Agr, Dept Soil Sci, 11 Padua Dias Ave, BR-13418900 Piracicaba, SP - Brazil

• Document type: Journal article
• Source: Geoderma; v. 371, JUL 15 2020.
• Web of Science Citations: 0

Abstract

Integrated farming systems are sustainable strategies to intensify land productivity by combining annual crop, livestock and/or forestry activities in different spatio-temporal arrangements. Therefore, they may help tackle global food and energy insecurity and climate change in the coming decades. We investigated the effects of integrated crop-livestock (ICL) and integrated crop-livestock-forestry (ICLF) systems on quantity, quality, and origin of soil organic matter (SOM) in southeastern Brazil. A native forest and an extensive low-grazing intensity pasture system were used as references. In integrated systems, corn (Zea mays) was alternated with two consecutive years of piata grass (Urochloa bryzantha) for cattle grazing. In ICLF, eucalyptus trees (Eucalyptus zrograndis) were planted in simple rows of 15 x 2 m. Soil sampling was performed three times; in 2014, after two years of grazing; in 2015, after crop cultivation; and in 2016, after a successive grazing year, to evaluate chemical and physical composition changes of organic matter (C, N, delta C-13, delta N-15, and organic matter fractions) with time. Our findings showed that from 2010 to 2016, all systems (extensive grazing, ICL and ICLF) promoted increments on soil C and N stocks. However, land intensification converting extensive low-grazing intensity pasture to ICL was the most promising strategy, increasing soil C stocks at the rate of 0.28 Mg C ha(-1) yr(-1) from 2010 to 2016. Annual crop cultivation (corn intercropped with piata grass) promoted high organic matter inputs on the soil, increasing the amount of soil labile organic matter fractions, which presented higher delta C-13 and lower delta N-15 values over time. SOM in the integrated farming systems was originated mainly from C-4 plants. Therefore, optimizing development of piata grass and corn increases organic residue inputs and then, soil C and N stocks. In addition, the crop period increased soil fertility parameters, which favors plant growth, thus providing high labile C inputs to the soil. In contrast, land intensification by adding the forestry component into the system (i.e., conversion from ICL to ICLF) reduced soil C (-0.22 Mg C ha(-1) yr(-1)) and N (-0.03 Mg N ha(-1) yr(-1)) stocks from 2010 to 2016, likely due to the reduction of C and N inputs to the soil caused by limited growth of annual crop and grass species under tree shades. In conclusion, land use intensification through ICL system contributes towards a more efficient and low-C agriculture, whereas the studied ICLF system did not bring further benefits to increase the quantity and/or quality of SOM. (AU)

• FAPESP's process: 14/17927-2 - Growth and decomposition of fine roots and soil quality under integration of agriculture, livestock and forestry systems (São Carlos, SP)
• Grantee: Wanderlei Bieluczyk
• Support Opportunities: Scholarships in Brazil - Doctorate
• FAPESP's process: 19/21532-7 - Organic phosphorus changes with land use change in Brazil
• Grantee: Amin Soltangheisi
• Support Opportunities: Scholarships abroad - Research Internship - Post-doctor
• FAPESP's process: 18/09845-7 - Implications of expansion and management intensification on soil ecosystem services
• Grantee: Maurício Roberto Cherubin
• Support Opportunities: Regular Research Grants