Evaluation To The Effect Of Slow-release Fertilizer On Agricultural Environmental Emissions Abatement

The environmental problems caused by emissions of greenhouse gases, including CO2, CH4, N2O, and NH3or sewage disposal are becoming increasingly prominent.-Among these problems, emission of fertilizer and other agricultural disposal is one of the important inputs. New slow release fertilizers play an important role in improving the efficiency of fertilizer use; it is a great significance that we study reducing greenhouse gas emissions. In this experiment, we study the effects of slow release fertilizers on greenhouse gases of soil and NH3emissions. The results are as follows:(1) The nitrogen fertilizer application could affect soil CO2emission. And the result obtained from the soil treatment via WFPS60%showed that the CO2emissions in the soil were positively correlated to fertilization application, while the effect of common urea on the CO2emissions of the soil was more significant than slow-release urea, up to24.69%. The result achieved from experiment treated by waterlogged soil showed that fertilization could restrain the CO2emission. Compared to the slow-release urea, the common urea promoted CO2emission. The average emission flux of CO2decreased1245.70mg·m-2·d-1, that was to reduce13.51%. The phenomenon that the CO2emission of the control is higher than the fertilization treatment under waterlogged conditions still needed further study.(2) The CH4emission of the soil was mainly affected by the soil moisture and nitrogen fertilizer could restrain the CH4emissions. The higher soil CH4emissions would be obtaned from the higher soil moisture condition. And the result obtained, from the soil treatment via WFPS60%showed that CH4emission in soil was relatively slow, especially by fertilization treatment. Due to the inhibitory effect of fertilization on CH4emission, emissions flux of the fertilization treatment obviously decreased. Furthermore, inhibitory effect of slow-release urea on CH4emission in the soil than common urea’s, and the average emission flux of CH4emission of the soil decreased23.35ug·m-2· d-1, that was to decrease3.01%; The result achieved from experiment treated by waterlogged soil showed that nitrogen fertilizer restrained CH4 emissions in the soil and the CH4from the control treatment was obviously higher than the fertilization treatment. Similarly, the emission flux of slow-release urea CH4lower was obviously lower than common urea’s, and the average emission flux decreased0.31mg· m-2·d-1, that was to decreased17.44%.(3) The study on N2O showed that nitrogen fertilizer promoted N2O emissions in the soil, and the promoting effect of common urea on N2O emissions in the soil was greater than slow-release urea, but the performance of influencing effect would make a time lag. It found by compared with the same moisture and fertilizer treatment comparison that under60%WFPS in soil N2O emissions in the soil began to increase on the twenty-third day of cultivation by different temperature treatments, and the time difference of the N2O emission of the soil under waterlogged condition is earlier than the former which began on the seventh days after culturation.Compared to the common urea, the N2O emission flux in soil of slow-release urea decreased0.73mg·m-2·d-1, that was to decrease26.75%under60%WFPS soil condition. Compared to the common urea, the N2O emission flux in the soil of slow-release urea decreased156.70mg·m-2·d-1,that was to decrease44.62%, by the treatment of the waterlogged soil.(4) There is great effect of different nitrogen fertilizers on soil NH3emissions, although the soil in this study was acidic and NH3release amount is little, the experimental results showed that fertilization promoted the NH3emission. Soil, boosting rate of NH3emissions of slow-release urea soil was slower than common urea under WFPS60%condition, and decreased0.0321g, that was to reduced24.36%. Under water logging conditions, NH3emission was relatively slow, while the promoting effect of common urea on NH3emissions in the soil was greater than slow-release urea, that was to NH3emissions in soil of slow-release urea decreased0.4372mg, namely46.61%, than common urea.(5) The result obtained from different nitrogen fertilizers treatments showed that there was great difference between leaching rate of slow release urea and common urea leaching either in the soil column or in sand column. Slow release urea was capable to degraded controlled release agent due to the presence of the soil microorganisms, which quickly promoted nutrient release of nitrogen, while sand column had only single water soluble fertilizer, resulting in lower release rate of slow-release urea release.