Study On Nutrient Management Technology For Spring Maize In Field Scale

Jilin Province is one of the main maize area of China has played an important role in maize production. Maize fertilizer application showed a rising trend with the cultivation area and yield growth.However,in recent years unreasonable fertilizer application had decreased economic efficiency and fertilizer use efficiency and made a certain degree of threat to environment.Therefore,it is necessary to determine the different stages fertilizer application and calculate nutrient supply for spring maize according to nutrient uptake of spring corn at different growth stages and indigenous nutrient supply capacity of different soil layers.In order to increase fertilizer use efface build nutrient resource management system for spring maize,climate condition and the influence on environment were also considered.In this paper,the experiments conducted in Dehui City of Songliao Plain black-soil corn belt as long term spot experiments with different fertilizations.The paper mainly studies changes of maize yield with different treatments,dry matter accumulation and nitrogen accumulation characteristics with different treatments,distribution features of soil residue N before sowing and after harvesting.1,Analysis on yield increasing effect,nutrient use efficiency and nitrogen balance the results are as follow: Analysis on maize yields with different fertilizer treatment of long-term experiment from 2004 to 2007,the results showed that the average yield of onetime application was 11131 kg/hm~2;traditional application was 11779 kg/hm~2;recommended application was 11442 kg/hm~2;the slow release nitrogen fertilizer wasl 1748 kg/hm~2.The maize yields of onetime application,traditional application,recommend and slow release nitrogen fertilizer were no obvious difference in 2004,whereas the four treatments were significant differences in 2005 and in 2006.In 2007 the maize yields were no obvious difference.As experiment area has high soil basic fertility the output of Ck from 2004 to 2007 was respectively 9110 kg/hm~2,7598 kg/hm~2,4182 kg/hm~2 and 3812 kg/hm~2.Soil inorganic nitrogen content and soil sustained nitrogen supplying capacity were decreasing resulted yield reduction from 2004 to2007.Thus,soil sustained nitrogen supplying capacity impacts on maize yield.2,Study on dry matter accumulation and nitrogen accumulation characteristics with different treatments,the results shouted corn biomass presented a tendency of straight climb with growing process.The nitrogen absorption were increasing during growing process.At jointing stage(June 15),the corn biomass with different treatments were no obvious difference but the corn biomass of recommend was largest.At tassel ling period(July 15) the corn biomass with different treatments were significant differences,the corn biomass of slow release nitrogen fertilizer was largest.At sinking time(July 23) traditional application had the highest corn biomass.From sinking time(July 23) to filling stage(August 20),the corn biomass of onetime application rising range was higher than other treatments.From the filling stage(August 23) to maturity stage (September 26) the corn biomass of traditional application,recommend and slow release nitrogen fertilizer were no obvious difference,at the same time the corn biomass of recommend presented a tendency of straight climb and reached the highest value at maturity stage.3,Study on dynamic change of soil residue N with different treatment in 2005,results showed the value of onetime application,traditional application and recommend were no obvious difference before sowing.At jointing stage soil residue N with different treatments were up to crave peak.At sinking time soil residue N of onetime application and slow release nitrogen fertilizer were decaling.From the filling stage to maturity stage soil residue N of traditional application slow release nitrogen fertilizer and onetime application were no obvious difference but soil residue N of Ck was lowest.From soil surface to 90 cm layer the highest nitrate nitrogen content was slow release nitrogen fertilizer:204.9 kg/hm~2(.During four years the accumulations of recommended treatment were less than 150 kg/hm~2,which did not cause potential threat to groundwater.4,Analysis on apparent nitrogen balance of the four years,there sults showed nitrogen surpluses of recommended treatment and traditional application were positive in 2004,compared with the nitrogen surplus of traditional application was positive others were negative in 2005.In 2006 the nitrogen surplus of onetime application and recommended treatment were positive others were negative,by 2007,the nitrogen surplus of traditional application was positive and the rest are negative.Nitrogen fertilizer application resulted in the net loss of nitrogen after a physiological cycle and the loss increasing with a higher application.As the main fate of surplus nitrogen is leaching loss and gaseous volatilization,reasonable fertilizer applying is an effective measures to protect farmland fertilizer nitrogen balance and the environment.