The Effect of Tillage Systems on Soil Hidrophysical Properties and Drainage Outflow.

A field experiment was established in separately tile-drained plots on a loam soil in Midle Lithuanian Lowland with a mean precipitation of 590 mm per year and the annual mean temperature + 6.1°C. The tillage experiment distinguished between conventional tillage (CT) with mouldboard ploughing 23-25 cm depth after harvest in August-September, late ploughing (LP) in the end of October - beginning of November and reduced tillage (RT). The aim of this work was to study the effects of three tillage systems on soil physical properties, soil water content and drainage outflow, during the six successive year's treatments (2005-2010). The reliability of the results was determined by processing them with mathematical-statistical methods using MS Excel 2000 Data Analysis Tool Pack. Differences of tillage treatments were tested at the significance level p≤0.05. When considered across all the tillage treatments reduced tillage resulted in significantly higher (by 9-11%) soil water content in surface layer (0-20 cm) compared to traditional tillage while the differences between other tillage treatments were insignificant. Reduced tillage may be considered as a measure for drainage outflow retention in springtime especially under the dry spring period, because during spring peak (in March) the average monthly drainage outflow in reduced tillage system was 7% lower compared to late ploughing at the end of October - beginning of November and 23% lower compared to conventional tillage after the harvesting. [ABSTRACT FROM AUTHOR]