The objective of this study was to determine the changes in chemical characteristics following 40 years of a conventionally tilled continuous maize cropping (CM) compared with those of an adjacent untilled native grass-land (NG) soil. Results indicate that there was a significant decrease of organic C and N, of the exchange capacity and exchangeable bases as well as of the enzyme activities. In spite of a general decline in the content, but not of the concentrations of the inorganic N forms, the NO3-N/NH4-N ratio increased in the tilled system CM. As a consequence of yearly fertilization in excess of crop removal, cultivation enhanced the available P and soluble S contents as well as the heavy metal level, without, however, causing toxic concentrations in soil. Long-term maize cultivation did not seem to cause any adverse effect on soil pH, texture and electrical conductivity.
Chemical characteristics of soil after 40 years of continuous maize cultivation
SAVIOZZI, ALESSANDRO;
1994-01-01
Abstract
The objective of this study was to determine the changes in chemical characteristics following 40 years of a conventionally tilled continuous maize cropping (CM) compared with those of an adjacent untilled native grass-land (NG) soil. Results indicate that there was a significant decrease of organic C and N, of the exchange capacity and exchangeable bases as well as of the enzyme activities. In spite of a general decline in the content, but not of the concentrations of the inorganic N forms, the NO3-N/NH4-N ratio increased in the tilled system CM. As a consequence of yearly fertilization in excess of crop removal, cultivation enhanced the available P and soluble S contents as well as the heavy metal level, without, however, causing toxic concentrations in soil. Long-term maize cultivation did not seem to cause any adverse effect on soil pH, texture and electrical conductivity.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.