Data/hora: 23/05/2024 07:58:29

Biblioteca(s): 	Embrapa Soja.	
Data corrente: 	06/12/2005	
Data da última atualização: 	06/12/2005	
Autoria: 	BROWN, G. G.; MARTINS, P. T.; MATSUMURA, C.; SILVA, S. H. da; FERRARI, E.; PASINI, A.	
Título: 	Growth of Pontoscolex corethururus in soils of different textures and contents of organic matter.	
Ano de publicação: 	2005	
Fonte/Imprenta: 	In: ENCUENTRO LATINO-AMERICANO DE ECOLOGIA Y TAXONOMIA DE OLIGOQUETOS, 2., 2005, San Juan, Puerto Rico. [Resumenes]. San Juan, Puerto Rico: International Institute of Tropical Forestry: Fundación Puertorriqueña de Conservación, 2005. p. 38.	
Idioma: 	Inglês	
Conteúdo: 	Pontoscolex corethrurus is a pantropical geophagous endogenic erathworm species native to the Guyana Shield area in Northern Brazil. It is found throughout the Country, mainly in disturbed ecosystems, although it also may inhabit natural ecosystems far from its original habitat, where it must be considered an exotic invasive species. Nevertheless, the species is absent in many of the cultivated soils near Londrina, Paraná State, Brazil, where its presence could cause important modifications to soil properties. In order to evaluate the possible reasons for the absence of this species at the Embrapa Soybean experiment station, a laboratory study was conducted using the Rhodic Hapludox from the station and different amounts of added organic matter (OM; composted city organic astes) and sand. The following treatments were used: 100% soil; soil+2% (weight) OM; soil+4% OM; soil+10% OM; soil+10% sand; soil+30% sand; soil+60% sand. Mean C content os the mixtures ranged from 1.2 to 4.3% and sand contents from 8 to 76%. Each container (10 cm square plastic box) received about 140g air dry substrate, and water at 70-80% field capacity. Each box had 1 specimen and 14 replicates. The worms were cultivated for 395 d, and the substrates chnged approximately every 20 d. A negative relationship was observed beteween sand content and earthworm biomass (R² = 0,60). Worm biomass and soil C content showed a polynomial relationship (R² = 0,89), with maximum values at 2.8% C. Positive linear correlations (R² = 0,5) with soil P and Mg were also observed. Worms grew best in soil+2% OM, followed by soil+10% sand, soil+4% OM, soil 100%, and soil+30% sand. Therefore, the soil from the station was not limiting in itself and another factor must be limiting colonization of Embrapa Soybean's soils by P. corethrurus. Afetr 1 yr, only 5 worms were alive in the soil+60% sand treatment and>9 individuals in the remaining treatments. It is well known that this compacting species can cause complications to the soil's physical structure in the abscence of other bioturbating invertebrates, although it can also lead to important modifications to the soil's chemical features, generally enhancing plant nutrient availability.	
Categoria do assunto: 	--	
Registro original: 	Embrapa Soja (CNPSO)	
Exemplares: 	CNPSO - (25819-1) - UPC - SP - -- - 10691 -  - 10691 - DIS