Nutrient dynamics in a dryland corn cropping system in Northern China: Effects of crop residue, animal manure and NP fertilizer applications

摘要

A long-term field experiment was carried out in the dryland of Shouyang in Northern China to assess the effects of applications of corn stover, cattle manure and NP (i : 0.44) fertilizer on com yield and nutrient dynamics in a spring com cropping system under dryland conditions. The experiment was set-up according to a D optimal design, with 3 factors, 11 treatments and a control. Combined applications of fertilizer NP with manure and corn stover gave higher yields than sole application of fertilizer NP. Fertilizer NP use efficiency was also increased with combined applications of manure and corn stover. The beneficial effects of combined applications were ascribed to the application of K, organic matter and possible other nutrients with the application of corn stover and cattle manure. Applications of fertilizer NP, corn stover and cattle manure increased soil mineral N after harvest, and soil available P and K. Strong increases in soil mineral N were observed following application of the highest rate of N fertilizer application (210 kg/ha). Increases in soil mineral N and soil available P and K in the sub soil (40-100 cm) provide evidence of leaching of N, P and K under dryland conditions.