Rice yields and nutrient uptake under different ploughing depths and fertilizations in white soil

Field experiments were conducted to study effects of different phonghing depths and fertilizations on rice yields, nutrient uptakes and soil physical and chemical properties in white soil of paddy fields. The treatments consisted of two ploughing depths of 10 cm and 20 cm (T10, T20) and four fertilization systems of chemical fertilizer (F), chemical fertilizer and farmyard manure (F+M), chemical fertilizer and wheat straw (F+S), chemical fertilizer and green manure (F+G). The results show that compared to the T10+F, rice yield is decreased by 7.6% in the T20+F, and the applications of wheat straw, farmyard manure, and green manure with ploughing depth of 20 cm can significantly increase the yields by 14.8% (T20+F+S), 16.1% (T20+F+M) and 14.6% (T20+F+G), respectively. Similar patterns are showed in N, P and K uptakes. The contents of soil organic matter, total N, available N, available P and available K in the T20+F+S, T20+F+M, and T20+F+G treatments are higher than those in the T10+F and T20+F treatments. In conclusion, the application of organic manure combined with ploughing depth of 20 cm in white soil can increase rice yields and nutrient uptakes, improve soil fertility in plough layer, and can be recommended for rice production in white soil areas.