A Mediterranean soil affected by long-term crop management systems was evaluated to identify the best indicators of its quality. Selected characteristics included total soil organic carbon (TOC), light fraction carbon (LFC), acid hydrolyzable and water-soluble carbohydrates carbon (AHG-C and WSC-C), phenolic carbon (PC), mineralizable carbon (Q), microbial biomass carbon (MB-C) and metabolic quotients (qCO(2) and qD). Soil samples were taken under natural grass (NG), an orange grove (OG), winter wheat (WW) and horticultural cropping (HC). The results show that WW and HC reduced different C fractions probably due to the routine annual ploughing and low inputs of plant residues compared with the undisturbed system (NG). The OG, receiving more organic matter and not tilled for seven years, showed intermediate values. Among the different indices for assessing quantity changes due to management practices, LFC and Q appeared to be the best. However, when the amounts of the different C parameters were expressed as percentages of TOC, most of the differences between the soils in the management systems disappeared.
Conventional crop management effects on soil organic matter characteristics
SAVIOZZI, ALESSANDRO;CARDELLI, ROBERTO
2003-01-01
Abstract
A Mediterranean soil affected by long-term crop management systems was evaluated to identify the best indicators of its quality. Selected characteristics included total soil organic carbon (TOC), light fraction carbon (LFC), acid hydrolyzable and water-soluble carbohydrates carbon (AHG-C and WSC-C), phenolic carbon (PC), mineralizable carbon (Q), microbial biomass carbon (MB-C) and metabolic quotients (qCO(2) and qD). Soil samples were taken under natural grass (NG), an orange grove (OG), winter wheat (WW) and horticultural cropping (HC). The results show that WW and HC reduced different C fractions probably due to the routine annual ploughing and low inputs of plant residues compared with the undisturbed system (NG). The OG, receiving more organic matter and not tilled for seven years, showed intermediate values. Among the different indices for assessing quantity changes due to management practices, LFC and Q appeared to be the best. However, when the amounts of the different C parameters were expressed as percentages of TOC, most of the differences between the soils in the management systems disappeared.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.