Effect Of Urea Formaldehyde Fertilizer On Banana Growth,Nitrogen Fate,Greenhouse Effect

Urea formaldehyde?UF?fertilizer is a kind of chemosynthesisslow-release fertilizerthat was super than N inhibitorfertilizers and matrix slow release fertilizer.The UF nitrogen is stable and with few leaching losses in the tropic and sub-tropic regions with heavy rainfall and high temperature,and in favor of the agricultural production.The UF slow-release nitrogen fertilizer can be used as pure slow-release nitrogen fertilizer or be aslow-release nitrogen compound.The UF nitrogen possesses long effect to supply nitrogen which may causepoor crop growth and high costbecause shortage of available nitrogenduring the early growth period.The UF compound fertilizer consist of nitrogen,which take the advantages of slow-release nitrogen,guarantee the sufficient amount of available nitrogen to meet the nitrogen requirement in each stageand reduce the cost of the fertilizer.In this paper,the UF nitrogen fertilizer and UF slow-release compound fertilizer being used as the tested fertilizers,different kinds way of fertilization e ffects on banana biomass,nitrogen use efficiency,nitrogen leaching loss,soil nitrogen and soil nitrogen fate,have been thoroughlystudied in previous experiment.At the same time,the influencesof UF slow-release compound fertilizer on soilN₂O emission have beenstudied.The results will begreat importance to evaluatethe work and the environment effect of the fertilizer,and then provide a theoretical basis for the development and application of UF slow-release fertilizerin agriculture.1.Under the condition of noleaching,UF slow-release nitrogen fertilizer and fertilization pattern showed no significant effect on nitrogen uptakebybanana.The N itrogen uptake was no significant different,being from 1.1 to 1.2g for both singlebasal and splitting application of UF fertilizer,common fertilizer and conventional UFnitrogen fertilizer..Compared with urea,UF slow-release fertilizer promoted the nitrogenuptake and nitrogen utilization efficiency of bananaunder leaching condition.Thebiomassand nitrogen uptake of UFslow-release nitrogen fertilizertreated banana increased by 10.2%and 12.0%in single basal application,while increased by 43.7%and 21.4%in splitting application.Compare with the conventional fertilizer,the banana biomass and nitrogen uptakein UF compound fertilizerof basal treatment were increasingby 20.6%and 41.2%.2.Compared with urea,no matter one-timeapplication orsplitting application.To instead of urea by UF slow-release fertilizerwould significantly reduce the nitrogen leaching and N losses.Thenitrogen leaching losses ofUF slow-release nitrogen fertilizer and UF mixed with urea were36.2%and 44.7%under single application respectively and44.6%and 62.2%under splitting one.The nitrogen leaching losses ofUF compound fertilizer and UF compound mixed with urea were73.8%and 83.7%of those of conventional fertilizerrespectively.3.No matter what kind s of fertilizer,splitting application enhancedthe nitrogen absorption and decreased the leaching losses of nitrogen.Compared with single application,splitting application of UF nitrogen fertilizer,UF nitrogen mixed with urea fertilizerand conventional fertilizercould increase the nitrogenabsorption of banana by 18.8%,39.7%and 29.1%respectively and decrease nitrogen-leaching lossesby 23.4%,37.9%and 29.4%respectively.The splitting application of conventional fertilizer treatment could also increase banananitrogenabsorption by 39.5%and decreased soil nitrogen leaching loss by20.7%.4.Compared with the single basal application of conventional fertilizer,use of UF compound fertilizer would significantly decrease the peak of N₂O emission,accumulative emission of N₂Oand global warming potentialof the N₂O.Meanwhile,application of UFalso alleviated the negative effect of N₂O emission from field ecosystem.The highest peak value of N₂O emission in UF compound fertilizer treatment,UF mixed with urea fertilizer and conventional fertilizer treatment were 111.8 mg·m^-2·d^-1,130.7 mg·m^-2·d^-1 and163.1 mg·m^-2·d^-1respectively.The results showed that the conventional fertilizer treatmenthad the highest peak.The N₂O cumulative emission ofUF compound fertilizer was 82.3%of the conventional fertilizer and the global warming potential?GWP?of N₂O was 21.8%lower than that of the conventional fertilizer treatment.5.Under both non-leaching and leaching condition,the application of UF slow-release fertilizer changed the nitrogen fate and promoted the nitrogen absorption by banana and residualnitrogenin soil,thus reducing the loss of nitrogen.Compared with the conventional fertilizer treatment,the single basal application and split application of UF nitrogen fertilizer treatmentincreasednitrogen residue by 204%and 215%and decreased the apparent lossby 24.7%and 23%under the condition of non-leaching.Regarding to the leaching,the single basal application and split application of UF nitrogen fertilizer decreasedthe nitrogen loss caused by leaching by 63.8%and 55.3%respectively compared with conventional fertilizer treatment.Compared with conventional fertilizer used as basal fertilizer treatment,UF compound fertilizer decreased nitrogen leaching loss,N₂O gaseous loss and the other apparent loss by 26.2%,26.2%and 18.0%respectively,while residual soil increased by 242.7%.