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Individual study: Long-term pig manure application reduces the requirement of chemical phosphorus and potassium in two rice-wheat sites in subtropical China

Published source details

Duan Y., Xu M., He X., Li S. & Sun X. (2011) Long-term pig manure application reduces the requirement of chemical phosphorus and potassium in two rice-wheat sites in subtropical China. Soil Use and Management, 27, 427-436


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Amend the soil using a mix of organic and inorganic amendments Soil Fertility

A controlled, randomized, replicated experiment in 1982-2005 on clay loams in China (Duan et al. 2011) found higher nitrogen levels under nitrogen, phosphorus and manure (141 and 90 kg N/ha, for rice Oryza sativa and wheat Triticum aestivum respectively) and nitrogen/phosphorus/potassium (NPK) and manure (140 and 89 kg N/ha), than nitrogen and manure (119 and 70 kg N/ha) or the control (58 and 41 kg N/ha) at Suining. Levels were similar between treatments at Wuchang (approximately 100 and 75 kg N/ha). Plant nitrogen uptake was 15.5 and 11.4% higher in rice and wheat under nitrogen and phosphorus plus manure, and 12.8 and 10% higher under NPK plus manure compared to nitrogen plus manure. Rice and wheat yields increased by 23-26% and 21-58% respectively under nitrogen and phosphorus plus manure, and NPK plus manure treatments, compared to nitrogen plus manure (8.4 and 9.1 t/ha/y overall for Suining and Wuchang respectively). Four treatments were applied to rice–wheat rotations at two sites in China: no fertilizer, nitrogen plus manure, nitrogen and phosphorus plus manure, and NPK plus manure. Each treatment was replicated four times in 4 x 3 m plots at each site. Soil samples were taken annually (20 cm depth).