Study On The Dynamic Characteristics Of Organic Sulphur Mineralization In Brown Soil With Long-term Fertilization And Its Influencing Factors

In this paper,the open culture system was used to study the culture conditions at 20 ? and 30 ? long-term localization experiment of brown soil the mineralization characteristics of organic sulfur under different fertilization treatments and the changes of factors affect mineralization of organic sulfur under the condition of long-term fertilization.The results show that:(1)Under aerobic culture conditions,the mineralization of organic sulfur in brown soil increased with the increase of cultivation time,and the relationship between them followed the first-order kinetic model.Temperature affects soil organic sulfur mineralization and 30 ? is more favorable to soil organic sulfur mineralization.It was found that the mineralization of organic sulfur in each fertilization treatment increased gradually with the increase of the year 2014-2016.It can be seen that long-term fertilization can increase the amount of organic sulfur mineralization in soil,and the combination of organic fertilizer and chemical fertilizer is more effective.(2)The increase of temperature is beneficial to the mineralization of organic sulfur in the soil but the high mineralization intensity of organic sulfur is beneficial to the supply of sulfur in the short term and unfavorable to long-term transport of organic sulfur.The combined application of low amount of organic fertilizer and chemical fertilizer can improve the mineralization potential of soil organic sulfur and slow the reaction rate of organic sulfur mineralization,which is beneficial to the stable supply of sulfur to the soil.Fertilization can delay the arrival of half-life and prolong the time of sulfur supply,and low organic fertilizer combined with nitrogen,phosphorus and potassium has the best effect.With the growth of the year,the half-life is also growing.The half-life also changes with the change of temperature,and the half-life of lowering temperature will be prolonged.(3)The application of chemical fertilizer can reduce the soil acidity and alkalinity,and the application of organic fertilizer can increase the soil acidity and alkalinity,and the effect of single application of high amount of organic fertilizer is the most obvious.The total sulfur accumulation of NPK fertilizer treatment was higher than that of M1 NPK treatment,but the increase of total sulfur accumulation in each year was significantly lower than that in M1 NPK treatment,the total sulfur accumulation of M1 NPK treatment was not significantly different from that of NPK treatment,it can be concluded that low organic fertilizer combined with nitrogen,phosphorus and potassium fertilizer has the best effect on soil total sulfur accumulation gain.From 2014 to 2016,the accumulation of available sulfur in long-term fixed fertilization increased with the increase of the year,and the application of low organic fertilizer combined with nitrogen,phosphorus and potassium fertilizer had the best effect on the increase of soil available sulfur accumulation.(4)From 2014 to 2016,the contents of total nitrogen in fertilizer area,low amount organic fertilizer area and high amount organic fertilizer area were all decreased in 2015 and increased in 2016.From 2014 to 2016,the total nitrogen content of organic fertilizer was higher than that of chemical fertilizer,and except M2N2?M2 treatment in 2014 all the treatments showed that the application of high organic fertilizer was more favorable to the increase of soil total nitrogen content than that of low organic fertilizer application.The application of organic fertilizer can increase the total nitrogen content of soil and the effect of high organic fertilizer is better than that of low organic fertilizer.From 2014 to 2016,the organic matter content of each treatment showed a uniform rule:NP<M1NP<M2NP,NPK<M1NPK<M2NPK,N1<M1N1<M2N2,N2<M1N2<M2N2,CK<M1<M2.That is to say,when other fertilizers are the same,organic fertilizer can increase the content of organic matter in soil,and with the application of organic fertilizer,the content of organic matter in soil is higher.(5)Fertilization was beneficial to the improvement of soil aryl sulfate enzyme activity,and the application of organic fertilizer was more favorable to the increase of aryl sulfate enzyme than that of chemical fertilizer.The low organic fertilizer combined with nitrogen,phosphorus and potassium fertilizer was the most favorable for the activity of aryl sulfate enzyme.Fertilization was beneficial to increase the activity of neutral protease in soil,and the application of organic fertilizer in combination with chemical fertilizer was more favorable to the increase of neutral protease than that of applying chemical fertilizer alone or applying organic fertilizer alone.But the application of low organic fertilizer combined with nitrogen,phosphorus and potassium fertilizer and high organic fertilizer combined with chemical fertilizer had more obvious effect on the increase of soil neutral protease.