Adsorption-desorption Of Nitrogen From Biochar To Brown Soil And The Effect Of Corn Growth

The study selects the ZD 958 for maize variety tested,corn straw charcoal as material,adopt the method of combination of field test and laboratory test,a five carbon trading:0 kg/hm²?CK?,1250 kg/hm²?X1?,2500 kg/hm²?X2?,3750 kg/hm²?X3?,5000 kg/hm²?X4?.Based on soil nitrogen content,maize morphological index,physiological index,nitrogen metabolism related enzyme activity and the determination of corn yield and quality,etc,studied and analyzed the biological carbon to nitrogen adsorption-desorption effect increase the corn yield and nitrogen use efficiency,maize growth and soil physical and chemical properties,the influence of the main results were as follows:1.The proper amount of biochar and compound fertilizer mixing can effectively increase the maize yield,improve maize panicle traits,including X2?add biochar2500 kg/hm²?deal with the highest yield,13162.63 kg/hm²,than the yield was13.60%higher than that of the CK,difference reached significant level.The spike length of X2?2500kg/hm² added biochar?and X3?3750kg/hm² added biochar?increased significantly compared with that of the control group.The number of grains in X3?3750kg/hm² added biochar?treatment increased significantly.2.Apply normal fertilizer with biochar to effectively improve the physical and chemical properties of soil.Biochar reduce soil bulk density,and positively correlated with biochar added quantity,effect of biochar on soil of different depth soil bulk density differences,0-10 cm and 10-20 cm soil layer soil bulk density decreased significantly higher than that of 20 to 30 cm;The addition of biochar improved the soil water content,and the treatment effect of high amount of biochar was obvious.The effect of biochar on surface soil water content was significantly higher than that of deep soil.There was a positive correlation between the amount of biochar applied and the amount of soil cation exchange,which increased by 8.53-26.70%compared with the CK,and the difference was significant.3.Biochar significantly affects the adsorption and desorption of nitrogen from cultivated soil,promotes the early dry matter accumulation of maize,and effectively improves the utilization rate of nitrogen and the agricultural efficiency of nitrogen fertilizer.The addition of biochar enhanced the soil's ability to absorb total nitrogen,and the total nitrogen adsorption-desorption amount of X2?adding biochar of2500kg/hm²?was at a high level.Alkaline hydrolysis nitrogen in the soil residues during the reproductive period,on the whole,a downward trend,spinning tasseling stage,soil alkali-hydrolysable nitrogen content in the form of X2 processing is highest,123.3 mg/kg,is significantly higher than other processing;The content of nitrate nitrogen in the leaching solution treated with carbon was smaller than that of the control,and the adsorption effect of X2 treatment on nitrate nitrogen was optimal.The amount of ammonium nitrogen leaching loss treated b y X3?3750kg/hm² added with biochar?was always kept at a low level.The content of nitrate nitrogen and ammonium nitrogen in each treatment was greater than that of the control group.X4?5000kg/hm² added biochar?and X3 treatment increased NO₃ nitrogen desorption by13.45%and 10.72%respectively compared with control treatment.The amount of ammonium nitrogen desorption increased by 48.95%and 61.98%respectively in X2and X3 treatment.X3?biological carbon added 3750kg/hm²?treatment promoted dry matter accumulation in the early stage of maize breeding,and high amount of biological carbon inhibited dry matter growth in the later stage of maize breeding.Both the utilization rate of nitrogen and the agronomic efficiency of nitrogen fertilizer treated by X3 were higher than that of other carbonized treatments,and the difference was significant compared with that of the control group.4.In the later stage of maize growth,treatment with X3?adding biochar 3750kg/hm²?and X4?adding biochar 5000kg/hm²?can effectively improve the activity of nitrate reductase.X2?added biochar of 2500kg/hm²?was treated at a high level of glutamine synthase activity in the leaves during the whole growth period of maize.Add biochar on the early stage of the corn roots bleeding intensity had obvious effect,after the arrival in mid-season,biochar for the promotion of root bleeding intensity obviously improve,the entire reproductive period the X3 processing roots bleeding intensity at a higher level.Under the condition of normal fertilization add biochar can effectively slow the decline stage,SPAD value of corn,when excessive amounts of biochar addition,maize growth prophase SPAD value,keep the change in lower level.The application of biochar has significant effect on maize leaf area index,and the effect is obvious when the amount of biochar is high.Biochar had a certain inhibitory effect on the plant height of maize in the early stage of growth,which gradually disappeared with the advance of the growth period.The application of biochar can significantly improve the photosynthetic performance parameters of maize leaves,reduce stomatal limit value,increase stomatal permeability,and accelerate transpiration rate and net photosynthetic rate.