Study On Fertilization On Farmland System Of Greenhouse Gas Emissions And Ammonia Volatilization In Hetao Irrigation District

Crop nitrogen absorption of into farmland utilization rate is about 30%?40%,the nitrogen content of soil nitrogen excess surplus,70%of nitrogen residues in the soil evaporation in gaseous,liquid or leaching loss,leakage and other forms,cause varying degrees of pollution to the farmland ecosystem.Nitrogen gas emissions caused by warming potential cannot be ignored.Hetao irrigation utilization of nitrogen and phosphorus were 35%and 22.4%respectively,along with the increase of the fertilizer utilization ratio are low.In order to realize the irrigation area of grain production and environmental friendly win-win goal,urgently need to be proven in the irrigation area of nitrogen gas loss characteristics and the effective way of reducing the loss of nitrogen gas.Take alkaline meadow soil in Hetao Irrigation Area as a research object,slow controlled release fertilizers?HK?,particle organism organic fertilizer?F?,microbial fertilizer?W?and farmer accustomed fertilizer?CK?as four fertilization treatments.Comparing greenhouse gas emissions and potential increase of temperature under different treatments to provide rational fertilization methods in Hetao irrigated meadow alkaline soils.From May 2015 to October,emission characteristics of N₂O,CO₂ and CH₄ of maize land under different fertilization treatments were monitored by using static chamber gas chromatography,and at meantime their greenhouse effect was estimated as well.Result:?1?There is a significant difference of CO₂ emission between treatments.W treatment had the lowest emission amount and F treatment has the highest amount.CO₂emission under CK is 16.75%higher than that of W treatment.?2?N₂O emission peaks of all treatments appeared 10 days after fertilization and treatments under CK and F have the lowest and highest emission during the whole maize growing duration,respectively.N₂O emission under F treatment was 62.40%higher than CK treatment.N₂O emission under CK was respectively 19.71%and 54.26%higher than W and HK treatments.?3?The overall performance of CH₄ in each fertilizer treatment was absorption.HK in fertilizer 5?7 days after the emergence of emission peak,the highest value appeared in the application of base fertilizer after 10 days,followed by a gradual decrease to the absorption phenomenon.Soil water content was negatively correlated with CH₄ uptake.?4?Soil NH₃ volatilization occurred mainly in the heavy application of nitrogen fertilizer and high temperature and fertilization after 3 to 7 days after the peak.The total volatilization of NH₃ was the highest in the whole growth period of F.The W treatment could reduce the transfer of ammonium nitrogen from the soil colloid to the soil solution,thus reducing the soil NH₃ volatilization.?5?HK treatment has the lowest temperature?GHGI?,which is 96%lower than CK treatment.Due to the slow release of fertilizer,the demand of maize can be supplied with the same amount of N₂O emissions,which makes the potential of temperature increase at a low level.HK crop yield increased,GHGI value is the lowest,and the farmland greenhouse gas emission reduction is of great significance.