Effect of Nitrogenapplication Patterns on Variation of Soil Nitrate-N and Grain Yield of Wheat and Maize
|School||Henan Agricultural University|
|Keywords||Nitrogen application patterns winter wheat-summer maize rotation system soil nitrate-N yield nitrogen use efficiency|
Under the field experiment condition, effects of different nitrogen application patterns on yields of wheat and maize and nitrogen use efficiency were studied during 2008–2010. There were five treatments including no fertilizer （CK）, convention fertilizer （CON）, organic complex fertilizer （OMF）, controlled loss fertilizer （CLF） and changing basic fertilizer and topdressing regimes （CBT）. There were the same amounts of nitrogen （N） application with 250 kg.ha-1 in wheat season and 200 kg.ha-1 in maize season, and 80 % of the amount of nitrogen （N） application in each fertilizer treatment.The results were as follow:1. Effect of N application patterns on the Nitrate-N of soil.Results showed that, compared with CK, different nitrogen application patterns could increase the amount of nitrate-N and accumulation on the 0180 cm soil. It also showed that fertilizer application could remarkable increase nitrate-N on the 030cm soil, but had little effect on the 150180 cm soil. Nitrogen-N fertilizer application patterns represented that nitrate-N of soil increased after fertilizer application, and decreased with the growth of wheat and maize. Analyzed the data of nitrate-N, it was different between 2008-2009 and 2009-2010. At the convention level-N, the average of nitrate-N was no difference among Nitrogen-N fertilizer application patterns. The order was changing basic fertilizer and topdressing regimes （CBT）>organic complex fertilizer （OMF）>controlled loss fertilizer （CLF）> convention fertilizer （CON）. Compared with the common N2, at the level of N1, each layer of the soil of the same Nitrogen-N fertilizer application patterns had no significant difference, the differ of maximum value was 27.28 mg.kg-1 and the minimum was 4.58 mg.kg-1.Analyzed the accumulation of soil NO3--N after the harvest of the wheat and maize, compared with control,different nitrogen application patterns could increase over 4.11 N.kg.ha-1. And the NO3--N mainly was accumulated remarkable on 030 cm, 3080 cm especially, but the 120180 cm soil had no change. The accumulation of soil NO3--N was in the order; changing basic fertilizer and topdressing regimes （CBT）>organic complex fertilizer （OMF）>controlled loss fertilizer （CLF）> convention fertilizer （CON）. It had the same as 0.7231.12 N.kg.ha-1 as between N2 and N1 level. 2. Correlation between Accumulation of nitrate-N and water content at nitrogen application patternsResults showed that, the correlation exited between accumulation of nitrate-N and water content on the 0180 cm soil at the same N level of convention the fertilizer （CON）, organic complex fertilizer （OMF）, controlled loss fertilizer （CLF） and changing basic fertilizer and topdressing regimes （CBT）. No fertilizer （CK）, convention fertilizer （CON）, organic complex fertilizer （OMF）, controlled loss fertilizer （CLF） and changing basic fertilizer and topdressing regimes （CBT） represented negative correlation on 030 cm, it was opposite on 120180 cm soil; convention fertilizer （CON） represented positive correlation on 3080 cm, no fertilizer （CK） represented negative correlation on 80120 cm. Analyzed coefficient of correlation, it was significant on 030 cm, 3080 cm, 80120 cm for CK, and 3080 cm, 120180 cm for CON. Howere CBT was less significant.3. Effect of N application patterns on N accumulation of aboveground parts and N use efficiency of winter wheat and summer maizeResults showed that N fertilizer application could increase N accumulation of aboveground parts as CK. CK, OMF, CLF, CBT increased N accumulation all the time at the growth of wheat and maize. But it firstly increased, and then decreased for CON. At the N2 level, N accumulation of CLF was the highest at two season wheat, CBT was the lowest; OMF was the highest at two season maize, CON was the lowest. As the same as N2 level, at N1 level, CON, OMF, CLF and CBT had no significant difference, and the range was from 23.86 to 50.77 N.kg.ha-1 on winter wheat; it was from 28.74 to 31.81 N.kg.ha-1. Experiment results showed that N apparent nitrogen mineralization was average high 37.7 % of fertilizer nitrogen. At the same N level, as CON, NRE, NAE and NPEP could increase with CLF, OMF and CBT. Compared with N2 level, at N1 level, NAE increased and N apparent nitrogen loss decreased 34.05 % of fertilizer nitrogen for CON, OMF, CLF and CBT.4. Effect of nitrogen application patterns on winter wheat and summer maize yields and their componentsResults showed that, compared with CK, grain yield could increase with CON, CLF, OMF and CBT on wheat and maize. Analyzed different nitrogen application patterns at the same level of N2, compared with CK, CON, CLF, OMF and CBT could increase grain yield of wheat from 51.79 % to 58.65 % and maize from 22.16 % to 45.45 %; Compared with CON, CLF, OMF and CBT could increase yield of wheat from 2.44 % to 9.31 % and maize from -3.1 % to 10.52 %. Among nitrogen fertilizer application patterns treatments, the grain field of CLF was highest, and then was OMF, last was CBT. At the same level of N1, compared with CK, CON and CBT, including OMF and CLF, could increase grain field of wheat rang 49.86% to 58.05% and improve field of maize rang 18.67 % to 42.82 %; Compared with CON, OMF and CLF, including CBT, could increase grain field of wheat from 2.31 % to 9.91 %, However, OMF and CLF could only increase grain field rang 4.36 % to 10.52 %.In conclusion, compared with the common N level, at N1 level, CON, OMF, CLF and CBT could increase Nitrate-N of soil, decrease the accumulation of soil NO3--N and N apparent nitrogen loss after the harvest of the wheat and maize, improve NAE. Among the different nitrogen fertilizer application the increase of grain field was not remarkable. It was suggested that CON, OMF, CLF and CBT could be suitable for wheat and maize at the region.