Directory UMM :Data Elmu:jurnal:S:Soil & Tillage Research:Vol53.Issue2.Jan2000:
Soil & Tillage Research 53 (2000) 95±104
Effect of no-till cropping systems on soil organic matter in a sandy
clay loam Acrisol from Southern Brazil monitored by electron
spin resonance and nuclear magnetic resonance
CimeÂlio Bayera, Ladislau Martin-Netob,*, JoaÄo Mielniczukc, Carlos Alberto Cerettad
a
Universidade do Estado de Santa Catarina, C.P. 281, 88 520-000, Lages, SC, Brazil
Embrapa-Instrumentac,aÄo AgropecuaÂria, C.P. 741, 13 560-970, SaÄo Carlos, SP, Brazil
c
Universidade Federal do Rio Grande do sul, C.P. 776, 90 001-970, Porto Alegre, RS, Brazil
d
Universidade Federal de Santa Maria, 97 105-900, Santa Maria, RS, Brazil
b
Received 27 April 1998; received in revised form 21 October 1998; accepted 24 August 1999
Abstract
In weathered tropical and subtropical soils organic matter is crucial for soil productivity and its quantity depends heavily on
soil management systems. This study evaluated the effect of no-till cropping systems on organic matter content and quality in
a sandy clay loam Acrisol soil (Paleudult in US taxonomy) from Southern Brazil. Ten cropping systems with varying additions
of C and N were conducted for 12 years (from 1983 to 1994). The addition of crop residues increased total organic carbon
(TOC) and total nitrogen (TN) in the soil at 0±17.5 cm depth, and this increase was directly related with C and N added or
recycled by the systems. The crop residues added to the soil were associated with reduced semiquinone free radical
concentration, detected by electron spin resonance (ESR), in the organo-mineral aggregates 150, 53±150,
20±53, 2±20 and
Effect of no-till cropping systems on soil organic matter in a sandy
clay loam Acrisol from Southern Brazil monitored by electron
spin resonance and nuclear magnetic resonance
CimeÂlio Bayera, Ladislau Martin-Netob,*, JoaÄo Mielniczukc, Carlos Alberto Cerettad
a
Universidade do Estado de Santa Catarina, C.P. 281, 88 520-000, Lages, SC, Brazil
Embrapa-Instrumentac,aÄo AgropecuaÂria, C.P. 741, 13 560-970, SaÄo Carlos, SP, Brazil
c
Universidade Federal do Rio Grande do sul, C.P. 776, 90 001-970, Porto Alegre, RS, Brazil
d
Universidade Federal de Santa Maria, 97 105-900, Santa Maria, RS, Brazil
b
Received 27 April 1998; received in revised form 21 October 1998; accepted 24 August 1999
Abstract
In weathered tropical and subtropical soils organic matter is crucial for soil productivity and its quantity depends heavily on
soil management systems. This study evaluated the effect of no-till cropping systems on organic matter content and quality in
a sandy clay loam Acrisol soil (Paleudult in US taxonomy) from Southern Brazil. Ten cropping systems with varying additions
of C and N were conducted for 12 years (from 1983 to 1994). The addition of crop residues increased total organic carbon
(TOC) and total nitrogen (TN) in the soil at 0±17.5 cm depth, and this increase was directly related with C and N added or
recycled by the systems. The crop residues added to the soil were associated with reduced semiquinone free radical
concentration, detected by electron spin resonance (ESR), in the organo-mineral aggregates 150, 53±150,
20±53, 2±20 and