EFFECTS of TILLAGE SYSTEMS ON DISTRIBUTION of SOIL CHEMICAL ATTRIBUTES IN SURFACE HORIZON OF A CLAYEY SOIL

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EFFECTS of TILLAGE SYSTEMS ON DISTRIBUTION of SOIL

CHEMICAL ATTRIBUTES IN SURFACE HORIZON OF A CLAYEY

SOIL

1_, 2_{, Mert Acar}1*_{,Nurullah Acir}3_{, Zeliha Bereket Barut}4

1 _y icelik@cu.edu.tr, *_{macar@cu.edu.tr} 2 hikmetgunal@gmail.com 3 nurullah.acir@ahievran.edu.tr

4 _{Department of Agricultural Machinery and Technologies Engineering,}

Adana, Turkey zbbarut@cu.edu.tr

The harvest residues onthe surface and lack of mechanical disturbance in reduced or no-till systems affects chemical propertiesof soils. The effects of the six tillage treatments on the distribution of some chemical properties within the first 30 cm depth was determined in a field trial conducted for 9 years on a high clay soil. The experiment was conducted using a randomized block design with 3 replicates. The treatments were composed of conventionally tilled with moldboard plow (CT-1 and CT-2), reduced till (RT-1, RT-2 and RT-3)using chisel, disc harrow and rototillers and zero tillage (NT). Disturbed soil samples were collected from 0-10 cm, 10-20 cm and 20-30 cm depths from each treatment plot following the corn harvest of 2015. Soil samples were analyzed for pH, electrical conductivity (EC), calcium carbonate (CaCO3), organic matter (OM), plant available phosphorus (P) and potassium (K) contents. Soil pH and CaCO3 were not affected by soil tillage at three depths. Soil pH was slightly but statistically non significantly increased with depths in NT, RT-2 and RT-3 treatments. Soil OM in the first 10 cm depth under NT and RT systems is considerably higher compared to CTtreatments.The OM content was only significantly different at only 0-10 cm depth among tillage practices. OM was significantly reduced with depth except for CT applications. The P and K concentrations were significantly reduced with depth in all applications. The highest mean P concentration (7.74 mg kg-1_{) in surface soils was obtained in NT and the lowest P} (4.07 mg kg-1_{) was obtained in CT-1 treatment. The use of moldboard plow in conventional} treatment led to homogeneous mixing of the chemical properties except P and K concentration in the first 30 cm of soil profile.

Keywords: Conventional, Organic matter, Phosphorus, Reduced, Zero tillage (*) This study was supported by TUBITAK (TOVAG 115O353)