عملکرد زیر شکن کج ساق توام با تیغه‌های سطحی در یک خاک با بافت رسی

The present research was intended to alleviate the problems and costs of deep tilling in sugarcane production in Mian-Ab sugarcane farms located in Khuzestan province, Iran. The main objective was to investigate the feasibility of subsoiling operations with bentleg subsoiler (BLS) equipped with shallow tines, a combination expected to increase the critical depth resulting in less power consumption and improved soil physical conditions. Six treatments arranged in a completely randomized block design were used to measure the draft force (except for the bulldozer mounted rippers), disturbed soil cross-sectional area and penetration resistance. The treatments included (1) subsoiling with rippers mounted on bulldozer, (2) BLS without attachment, (3), and (4) BLS equipped with single tine at working depths of ½ and ⅓ of target depth, (5) and (6) BLS equipped with two tines at ½ and ⅓ target depth. The experiment was replicated three times. The results indicated that BLS without attachment had the highest draft requirement as compared with other BLS treatments with shallow tines. In general, tine attachment resulted in less draft mainly due to displacement of critical depth to lower soil zones. Increasing the number and depth of shallow tines resulted in less draft force. The BLS equipped with two tines working at ½ target depth exhibited minimum drawbar power. The inclusion of shallow tines resulted in 21% reduction in drawbar power requirement as compared to BLS without tine attachment. The cross-sectional area of the soil tilled by ripper was minimum. Furthermore, the tilled area was not uniform and subsequent subsoiling operations were needed. The average soil cross-sectional area per unit width was improved by BLS treatments by a factor of 2.3 as compared with that of ripper. The highest cone index was obtained in plots tilled by ripper the BLS reduced this index in a significant manner. The soil worked with subsoiler equipped with tines exhibited the least resistance. The range of wheel slippage for BLS treatments was 12-16% which lies in the upper end of the recommended range for optimum traction efficiency. The proposed idea proved prominent in subsoiling fine textured compact soils.