Studies On The Effect Of Alkaline Liquid Compound Fertilizer On Banana Growth,Nitrogen Balance And Environment Effect

Traditional urea and compound fertilizer were the common products in C hina,which had low nitrogen use efficiency?NUE?and short fertility circle.In order to harvest higher yields in agricultural production,people often apply large fertilizers in soil,which had resulted in serious soil acidification.In order to deal with the problem,a new type offertilizer named alkaline liquid compound fertilizer?ALF?was developed by GuangdongProvincial R&D Center of Environmental Friendly Fertilizer Science and Technology.In previous research,it's has been showed that ALFincreased soil p H value significantly.Theoretically,the alkalinity of fertilizer may increase the loss of nitrogen,thus decreasing the nitrogen effect.In this circumstance,we want to know if ALF,which using long-term nitrogen as the source of nitrogen,can supply enough nitrogen to meet the need of plant as conventional compound fertilizer?CCF??For the problem discussed before,pot experiment was conducted to assess the effect of ALF,being developed by the authors,laboratory,on banana growth and nitrogen balance.Micro-lysimeter test was adopted to study the N₂O emissions and the greenhouse effect of ALF.In this paper,influences of the alkaline of the fertilizer onnitrogen fertilizer efficiency,the feasibilityof the ALF replacing the CCF and the difference of nitrogen balance between ALF and CCF were discussed.To the results of the research wouldprovide theoretical basis for ALF application in agriculture.The main research results were as followings.1.Under the condition of no leaching,the effectivenessapplication of ALF and CCF were the same during the banana growth,There was no significant difference between the two fertilizers;Under leaching conditions,ALF showed obvious advantages and the application of ALF could significantly increase the biomass and NUE of banana with the single-dose application treatment;Compared to the CCF treatment,the biomass and NUE were increased by 8.87%and 15.43%respectively;Under split application treatment,compared with CCF,the application of ALF did not increase the biomass of banana,however,the use of ALF could significantly promoted the absorption and use of nitrogen;The nitrogen use efficiency was increased by 5.97%.the results indicated that under the conditions of leaching,by use of ALFto instead of conventional fertilizer could not only promote the growth of banana,but also significantly improve the nitrogen use efficiency.2.Applying ALFcould significantly reduce the soil mineral nitrogen?N min?during early growth period of the banana,and also increased the proportion of ammonium nitrogen in soil N min.As the banana growth intomiddle period,with themineralization of thelong-term nitrogen in the ALF,the soil N min content would reach the level of CCF treatmentunder the condition of no leaching.Nevertheless,the soil N min content were significantly higher than that of CCFtreatment levelunder the condition of leaching.The resultsshowed that ALFhave strong aftereffect of fertilizerunder leaching conditions.3.Compared with the single-dose application method,ALF could obviously promote the growth of the banana and the absorption of nitrogen under split application way.Under no leaching conditions,banana biomass and nitrogen use efficiency could beincreased by 6.91%and 11.93%respectivelyby use of ALF with splitting methodthan those with single-dose application.Under leaching conditions,banana biomass and nitrogen use efficiency were significantlyincreased by 9.72%and18.43%respectivelyin treatment of splitting application than those in single-dose one by use of ALF.4.Compared to the CCF,under the condition of leaching,ALF possessed strong ability to resistant to leaching and could significantly reduce the leaching loss of nitrogen.Under the single-dose application,the amount of nitrogen leaching was134.98mg/pot in ALF treatment and183.35mg/pot in the CCF one.The former was18.75%of the total nitrogen,the latter one was 25.46%.The former was 26.38%less than that of the latter.Under split application method,the leaching rate of nitrogen fertilizer was significantly decreased,being 93.78 mg/pots,112.96 mg/potsin both of ALF and CCF treatment respectively.They were 13.03%and 15.69%of the total nitrogen fertilizer respectively.The leaching rate of the ALF treatment was still less than that of the CCF treatment by 16.98%.5.Under the condition of no leaching,the application of ALF did not change the equilibrium of nitrogen,bananas nitrogen uptake,soil nitrogen residue and nitrogen apparent loss compared with the CCF.However under leaching conditions,use of ALF would obviously change the fate of N in which the ALF application could promote nitrogen uptake and use,improve fertilizer use efficiency and decreasenitrogen leaching losses.6.Application of ALF did not increase N₂O emission.During the 60 days growth of the banana,the cumulative emission of N₂O was 2.42g·m^-2,and gaseous nitrogen losses were only 2.92%of total nitrogen fertilizers applied.In addition,there was no significant difference in soil N₂O cumulative emission and global warming potential between the ALF and CCF treatments.Therefore,to instead of CCF by the ALF would not aggravate greenhouse effect.