Dissolved organic nitrogen(DON)in soil is by testing the soil total nitrogen,ammonia nitrogen and nitrate nitrogen,then use the total nitrogen to subtract the number of ammonia nitrogen and nitrate nitrogen to obtain.Due to the different area or the different definition about DON,there are numerous extraction methods of soil nitrogen,which result in that there is no comparability between results.However,there is no unified understanding about what are control factors.Based on this background,the study applied orthogonal test method to statistically analyze the effects of shaking time,leaching agent,temperature,and soil-water ratio on the amount of soil ammonia nitrogen leached.The results show that the influences of different factors can be represented as:soil-water ratio＞leaching agent＞shaking time＞temperature.Extraction volume of ammonia showed an increasing with the increase of soil-water ratio and the concentration of extractors.When the extraction temperature lower than 50 ℃,the amount of soil ammonium nitrogen increase with temperature.Within 60 minutes of shaking time,the extraction of soil ammonium amount increased with the increase of shaking time.
万方数据
维普
