Soil plough layers and soil nutrients in western Liaoning
辽西地区土壤耕层及养分状况调查分析

At present soil plough layers of the farmland are obviously shallow, solid and little in the Northeast region of China, which have become into the main limiting factors for the development of regional agriculture. This paper studied soil plough layers and soil nutrients in western Liaoning. The results showed that the thickness of the mean plough layer in western Liaoning was 15.17 cm, which was 1.33 cm shallower than that of nationwide plough layer. Soil bulks of the effective plough layers in Fuxin, Tieling, Chaoyang and Chifeng were 2.27×106, 1.97×106, 1.95×106 and 1.79×106 kg/hm2 respectively, which were 16.5%, 27.6%, 28.3% and 34.2% lower than that of the normal effective plough layer (2.72×106 kg/hm2) respectively. The mean soil bulk densities in Fuxin, Tieling, Chaoyang and Chifeng were 1.32, 1.38, 1.33 and 1.33 g/cm3 respectively, all were higher than the suitable range (1.1 - 1.3 g/cm3) for crops normal growth. Meanwhile, soil nutrients in western Liaoning were low too. The general variation available phosphorus was maximum while that of pH was minimum.