02524naa a2200241 a 450000100080000000500110000800800410001910000210006024500970008126000090017852018290018765000150201665000160203165000190204765000140206670000170208070000240209770000140212170000170213570000220215270000230217477300850219711324642022-09-30       2022    bl uuuu     u00u1 u    #d1 aMUETANENE, B. A.  aSOIL ORGANIC MATTER, N AND P IN A SOIL CONSERVATION SYSTEM FOR ONION.h[electronic resource]  c2022  a000 02119 as  2200000uu 4500 008 220930s2022    bl eng   022 __ |a  2318-2407 100 __ |a MUETANENE, B. A. 245 __ |a SOIL ORGANIC MATTER, N AND P IN A SOIL CONSERVATION SYSTEM FOR ONION 260 __ |a Brazilian Journal of Agriculture, Piracicaba, SP, v. 97, n. 2, p. 172-185, |c 2022. 362 __ |a 2022 490 __ |v 97 520 __ |a The objective of this study was to evaluate soil chemical attributes in a soil conservation experiment for onion, under different cropping systems. The study was conducted on a Humic Dystrudept in Ituporanga, Santa Catarina state, Brazil. Eight different cropping systems for onion were evaluated: T1: maize-onion succession, T2: common vetch-maize/rye+fodder raddish-onionmaize/ rye+fodder raddish-common bean, T3: rye-onion-maize/black oat-maize, T4: onion-velvet bean succession, T5: rye-onion-millet/black oat-onion-millet, T6: rye-onion-velvet bean succession, T7: onion-velvet bean+millet+sunflower succession, from T1 to T7 were conducted under no tillage system T8: maize-onion succession, was conducted under conventional tillage system. We used the randomized complete block design, with 5 replications. The soil chemical samples were collected and evaluated at the 0-5, 5-10 and 10-20 cm soil layers, the soil chemical attributes evaluated as follows: total organic carbon, particulate organic carbon, carbon associated to soil minerals, N and P. At the 0-5 cm layer, P concentrations were severely affected by the different cropping system. In terms of treatments similarities, the treatments may be grouped in three clusters as follows: cluster 1: T2, T3, T7, cluster 2: T1 and T8 and cluster 3: T4, T5, T6. For N concentration, the different cropping system affected its concentration at the 10-20 cm layer. Carbon associated to soil minerals wasn¿t affected by the different cropping systems.  aclustering  acover crops  aCrops rotation  anutrients1 aALASSANE, D.1 aÁLVARO LUIZ MAFRA.1 aKURTZ, C.1 aBRITO, E. S.1 aPETERNELLI, L. A.1 aALBUQUERQUE, J. A.  tBrazilian Journal of Agriculture, Piracicaba, SPgv. 97, n. 2, p. 172-185, 2022.