Data/hora: 04/06/2024 16:44:42

Biblioteca(s): 	Embrapa Caprinos e Ovinos; Embrapa Milho e Sorgo.	
Data corrente: 	17/11/2011	
Data da última atualização: 	05/09/2018	
Autoria: 	SILVA, G. L.; LIMA, H. V.; CAMPANHA, M. M.; GILKES, R. J.; OLIVEIRA, T. S.	
Afiliação: 	Universidade Federal do Ceará (UFC) - Fortaleza, CE.; Universidade Federal Rural do Amazonas, Belém, PA.; MONICA MATOSO CAMPANHA, CNPMS; School of Earth and Environment, The University of Western Australia, Australia; UFC, Fortaleza, CE.	
Título: 	Soil physical quality of Luvisols under agroforestry, natural vegetation and conventional crop management systems in the Brazilian semi-arid region.	
Ano de publicação: 	2011	
Fonte/Imprenta: 	Geoderma, Amsterdam, v. 167/168, p. 61-70, Nov. 2011.	
DOI: 	10.1016/j.geoderma.2011.09.009	
Idioma: 	Inglês	
Conteúdo: 	The imposition of agricultural systems changes the natural equilibrium of the soil to an extent that it becomes dependant on management practices and soil resilience. Agroforestry systems (AFs) mimic characteristics of natural ecosystems such as multistrata canopy and deep rooting and may minimize the consequences of these changes by providing soil protection and maintenance of conditions similar to those under natural vegetation. This study evaluates the physical properties of a Luvisol at a site where since 1997 alternative agroforestry systems (AFs) (agrosilvipasture?AGP and silvipasture?SILV), conventional crop management (CCM) and natural vegetation (NV) have been maintained. Undisturbed soil cores were collected in 2005 and submitted to a range of matric suction for which soil bulk density (BD), soil penetration resistance (Q) and soil water content (?) were determined. Water retention and penetration resistance were used to determine the least limiting water range (LLWR) and the slope of the soil water retention curve at its inflection point (S-value). Particle size, total organic carbon (TOC) and particle density were determined using the disturbed soil samples. Water retention and porosity followed the sequence NVNSILVNCCMNAGP. The AFs studied (AGP and SILV) improved or maintained soil physical quality when compared to NV with no significant differences between the S-values of 0.044, 0.042 and 0.050, respectively. However, the S-value of 0.035 for CCM indicates that this management was unable to maintain soil physical quality on the same levels as AFs and NV. The decrease of LLWR with BD occurred for all treatments, and the BD at a maximum effect (LLWR=0) which is called the critical BD (BDc), was, respectively, 1.69, 1.62, 1.56 and 1.56 Mg m?3 for AGP, SILV, NV and CCM. The larger values of LLWR for AFs (AGP and SILV) are similar to the value for NV, with associated superior aeration, matric suction and reduced resistance to penetration by roots. Indices such as LLWR and S-value were suitably sensitive and could be used in future research, but it is important to identify other potential indices for these situations that can show how quickly changes in soil quality may occur.	
Palavras-Chave: 	Agroecologia; Agrofloresta; Agroforestry systems; Código florestal; Higroscopicidade; Least limiting water range; Resistência à penetração; S-value; Sistemas agroflorestais.	
Thesagro: 	Caatinga; Estrutura do solo; Manejo do solo; Retenção de água no solo; Solo.	
Thesaurus Nal: 	Agroecology; Brazil; Hygroscopicity; Semiarid soils; Soil management; Soil penetration resistance; Soil structure.	
Categoria do assunto: 	F Plantas e Produtos de Origem Vegetal
P Recursos Naturais, Ciências Ambientais e da Terra	
Registro original: 	Embrapa Milho e Sorgo (CNPMS)	
Exemplares: 	CNPC - (24856-1) - UPC - AP - DD -  -  -  - DIS
CNPMS - (24024-1) - ADD - AP - DD -  -  -  - DIS