The effects of reduced nitrogen application and straw deep buried on soil electrical conductivity

yield of maize and residuals of soil nitrate nitrogen were researched through field experiment conducted in spring maize planted with semi-plastic film in the Changwu State Key Agro-Ecological Station

and aimed to provide theoretical support for improving the efficiency of nitrogen use and protecting the environment. The experiment included five treatments with three replicates

no nitrogen fertilization application (CK)

conventional nitrogen fertilization application (CON1

N 250 kg/hm2)

conventional nitrogen fertilization plus straw (CON2

N 250 kg/hm2)

reduced nitrogen fertilization application (CR1

N 200 kg/hm2)

and reduced nitrogen fertilization application plus straw (CR2

N 200 kg/hm2). The soil electrical conductivity at different growth stages of spring maize was investigated

and the soil nitrate nitrogen content and spring maize yield during the harvest period were measured. The results showed that:the peak values of soil electrical conductivity at the stages of maize tillering and jointing appeared at the soil profile of 40-150 cm

at the stages of maize heading and maturing the peak values of soil electrical conductivity appeared at the soil profile of 40-200 cm

and the range of peak value moved down. In the 0-150 cm soil profile

the soil electrical conductivity followed the order of CON2 > CON1

CR2 > CR1. In the 0-150 cm soil layer

the soil electrical conductivity of conventional nitrogen application was higher than those of reduced nitrogen application treatments. Compared with the traditional nitrogen fertilization application

the reduced nitrogen application reduced the nitrate nitrogen content in the soil profile. At the same time

deep buried straw could also reduce the nitrate nitrogen content in the soil profile and postpone the soil nitrate nitrogen leaching. Compared with the traditional nitrogen application

20% reduction of nitrogen fertilization could increase the maize yield by 9.59%. On the condition of nitrogen application

deep burying of straw was beneficial to increase crop yield and the potential of nitrogen production. Straw deep burying was beneficial to improve soil electrical conductivity

reduce soil nitrate nitrogen content

control soil nitrate nitrogen leaching and increase corn yield.