Data/hora: 18/06/2024 20:40:16

Biblioteca(s): 	Embrapa Suínos e Aves.	
Data corrente: 	04/11/2020	
Data da última atualização: 	04/11/2020	
Autoria: 	WUADEN, C. R.; NICOLOSO, R. da S.; BARROS, E. C.; GRAVE, R. A.	
Afiliação: 	CAMILA ROSANE WUADEN, UDESC/Lages; RODRIGO DA SILVEIRA NICOLOSO, CNPSA; EVANDRO CARLOS BARROS, CNPSA; ROBERTO ANDRÉ GRAVE, IFC/Concórdia.	
Título: 	Early adoption of no-till mitigates soil organic carbon and nitrogen losses due to land use change.	
Ano de publicação: 	2020	
Fonte/Imprenta: 	Soil & Tillage Research, v. 204, 2020.	
DOI: 	https://doi.org/10.1016/j.still.2020.104728	
Idioma: 	Inglês	
Conteúdo: 	Abstract: Conversion of grasslands to agriculture has promoted land degradation and losses of soil organic carbon (SOC). Early adoption of no-till (NT) and use of organic fertilizers could mitigate SOC losses in response to minimum soil disturbance and increased carbon (C) inputs. To test this hypothesis, we assessed changes on soil C and nitrogen (N) pools in a Nitisol under natural grassland vegetation from Southern Brazil. The grassland was converted to agriculture in 2012 with a double-cropping system of maize (Zea mays L.) and black oats (Avena strigosa Scherb.). The experiment had split-plots replicated in four randomized blocks. Conventional tillage (CT) and NT systems were tested in the main plots (10 × 25 m, LxW). Maize was amended with 140 kg N-total ha&#8722;1 from different N sources in the subplots (10 × 5 m): urea (UR), pig slurry (PS), digested pig slurry (DS), and composted pig slurry (CS), besides a control treatment without fertilization (CTR). Soil was sampled in 2012 and 2017 to assess short-term changes (5 years) on total organic C (TOC) and N (TN) stocks in the 0&#8722;60 cm depth as well on the particulate and mineral associated C and N pools in the 0&#8722;30 cm soil layer. We also assessed C and N contents within water-stable aggregates (WSA) in the 0&#8722;5 cm soil layer. Soils under CT have lost 9 % of TOC and 21 % of TN (11.5 and 2.6 Mg ha&#8722;1, respectively) from the 0&#8722;60 cm layer as compared with original stocks under the grassland. No-till soils accumulated TOC at surface layers and mitigated TOC and TN losses by respective 82 and 34 % when compared with the grassland in the 0&#8722;60 cm layer. No-till increased particulate C and N fractions compensating losses on the respective mineral associated fractions. In contrast, depletion of mineral associated fractions accounted for most of total C and N stocks losses under CT. No-till soils had nearly doubled the mass of large macroaggregates and tripled the C and N contents within this WSA fraction as compared with CT. The use of CS augmented C and N contents within large macroaggregates by respective 35 and 40 % in comparison with UR and by 72 and 86 %, respectively, if compared with the CTR. Early adoption of NT can mitigate TOC losses following conversion of grasslands to agriculture. The association of NT with CS augmented C and N stabilization within large macroaggregates, improved soil quality and may contribute with SOC accrual in NT soils.	
Palavras-Chave: 	Biodigestion; Carbono orgânico do solo; Organic amendments; Perda de carbono orgânico.	
Thesagro: 	Adubo; Fertilizante; Manejo do Solo; Plantio Direto.	
Thesaurus Nal: 	Composted manure; Composting; No-tillage; Soil organic carbon.	
Categoria do assunto: 	--	
Registro original: 	Embrapa Suínos e Aves (CNPSA)	
Exemplares: 	CNPSA - (21959-1) - UPC - AP - DD -  -  -  - DIS