Data/hora: 11/05/2024 14:31:52

Biblioteca(s): 	Embrapa Cerrados; Embrapa Meio-Norte.	
Data corrente: 	17/09/1997	
Data da última atualização: 	07/10/2010	
Autoria: 	MENDES, I. de C.	
Título: 	Microbiology of soil aggregates recovered from different crop management systems.	
Ano de publicação: 	1997	
Fonte/Imprenta: 	Corvallis: Oregon State University, 1997.	
Páginas: 	138p.	
Idioma: 	Inglês	
Notas: 	Ph.D. Thesis.	
Conteúdo: 	My thesis research examined the relationship between soil structure and soil microorganisms. I examined the distribution of microbial biomass and its activities across soil aggregates and also the distribution across aggregates of a specific soil bacterium, Rhizobium leguminosarum bv trifolii. These distributions were evaluated in a summer vegetable cropping system in which three winter cover-crop treatments are practiced (fallow; cereal and legume). Five aggregate size classes (<0.25, 0.25 to0.5, 0.5 to 1.0, 1.0 to 2.0 and 2.0 to 5.0 mm) were obtained from each treatment by a dry sieving procedure. The distributions of total organic C (TOC), total Kjeldahl N (TKN), total soil bacterial population, microbial biomass C (MBC), mineralizable C and N (Min.C and Min.N), and two enzyme activities (B-glucosidase, FDA-hydrolysis) were measured after cover crop incorporation at seedbed preparation (June), and after harvest of the sweet-corn or broccoli summer crop (September). Immunofluorescence direct count microscopy (IFDC) and the plant infection soil dilution technique (MPN) were used to examine the seasonal distribution of R. leguminosarum bv trifolii across the same soil aggregate preparations. Despite the cover crop treatmens having been in place for seven years, they have not influenced the overall level of TOC, TKN, and aggregate size distribution. Cover crop effects on microbial soil interactions were subtle, often being seen at specific sampling  times and interacting with aggregate size. Rhizobium serotype ...	
Palavras-Chave: 	Microrganisms.	
Thesagro: 	Bactéria; Biomassa; Estrutura do Solo; Microbiologia do Solo; Microrganismo; População Microbiana; Rhizobium Leguminosarum.	
Thesaurus Nal: 	biomass; microbiology; soil biology; soil structure.	
Categoria do assunto: 	--	
Registro original: 	Embrapa Cerrados (CPAC)	
Exemplares: 	CPAC - (13823-1) - UPC - TS - -- - T004/97 - MEN - T004/97 - DIS
CPAMN - (24625-1) - ADD - TS - PP - T 56/97 -  - 1997.00056 - DIS