Research Of The (Super) High Yield Corn's Soil Fertility Characters

The corn growth is based on the good soil condition.Most nutrients the corn need are from soil.What fertility characters high yield soil needs isn't only a urgent question for corn planting,but also a important problem that study soil fertility cultivating for actual Songliao plain.In view of the above questions,this article has studied the topsoil's physical and chemical characters contrastive analysis.It has been clear that the physical and chemical environment and the influencing characters of corn yield.Through the detailed research of the soil nutrient change in the course of the corn growing,the dynamic change of available N,P,K is discussed under different period of high-yield corn growing.It'll establish the academic foundation for effectively regulating soil's nutrient supply for the future.That is significant for heightening corn output,and obtaining the best economy and the environment benefit.In addition,we studied the high and nature soil buffering to exterior acid and alkali environment,and probed into the influencing factors of the buffering combining with soil physical and chemical soil. Through the research of the rules from adsorbing NH₄⁺ and the influencing factors,we'll further understand the maintenance and adjustment ability of high-yield soil to the nitrogen.That can provide the reasonable applied nitrogen and the validity of nitrogen the theory basis.Through the above research,this article draws the following conclusion:(1) The(super) high yield field soil profile structure configuration is "Plane shape", whose depth is above 25cm,but the non-high-yield field's soil profile structure configuration is "Wave shape",their topsoil is only between 13 and 16cm.It is proved that "Plane shape" soil profile structure configuration and deep topsoil are necessary conditions of high yield.The high-yield soil's bulk density is lower.The high-yield field physical clay particles' mean value is higher than non-high-yield field's.The mean value of high-yield field's erosion rate is higher than non-high-yield's.The rate of structure breakage from non-high-yield field is higher than high-yield field's.Through soil aggregates analysis,high-yield field have more tiny particles than non-high-yield field.Through water stable aggregates analysis,non-high-yield field has better stability.Relativity analysis indicated that soil bulk density,topsoil thickness and corn yield had the extremely remarkable relations.The former have the plus relation to yields,but the latter have the inverse correlation.(2) The black soil,chernozem and alluvium from Jilin province,whose organic matter content can satisfy the need of high yield corn growth.Through chemistry analysis,the pH value, organic matter,available N,P,K,CEC aren't essential elements of high yield.The discrepancy from two sort of yields isn't distinct,in other words,they will provide fertility guarantee if their numerical values isn't lower than one value.(3) We have studied the dynamic available N,P,K,and pointed out that in the 0-30cm soil layer,(super) high yield soil's NH₄⁺-N and NO₃^-N contents are higher than ordinary soil in the livelong period of bearing and harvest.Under the condition of high yield,from the period of big trumpet-shaped to milk stage,available P is stable.After the harvest,the content of available P is lower than the period of sowing seeds.Thus it can be seen,to obtain the(super) high yield of crops,we must execute the right amount supplies of P.In the com's entire period of growing, available K changes stably.The differences of every process's K content aren't remarkable.(4) The buffering curve is counter-S shape,which has two inflexions,displaying the different sensitive sector.The relativity analysis results indicated that the soil organic matter content,CEC are related with the buffering ability,and the relativity is extremely remarkable (5%).The soil initial pH value and the buffering ability assume the inverse correlation,whose relativity is remarkable(1%).(5) Along with NH₄⁺ concentration increasing,the amount of sorption increases fast firstly then slowly.When NH₄⁺ concentration achieves one value,the reaction tends to be balanced.The increase of temperature is advantageous to increase the amount of adsorption to NH₄⁺.It is calculated that the thermodynamical parameters wereΔG＜0,ΔH＞0,ΔS＞0,which indicated that the adsorption is a spontaneous,endothermal,confusion increasing process.The increasing of organic matter content is advantageous in enhancing the adsorption ability to NH₄⁺, whose relativity is extremely remarkable.The dynamics process of soil adsorbing NH₄⁺ is divided to two stages:Initial rapid reaction stage and Low speed reaction stage after a period of time.The theory of transition state is applied to further calculate the adsorption reaction's activation thermodynamical parameters.ΔG^≠＞0,which explained that the reaction was needs the energy the process.ΔH^≠＞0,which showed the reaction is a endothermal process,namely consuming energy process.ΔS^≠＜0,which indicated system's degree of order was enhanced after adsorption.From the mechanism,it belongs to the association reaction.In two kind of NH₄⁺ concentration,along with ionic strength increasing,the brown soil reduces firstly then increases. Along with NH₄⁺ concentration increasing,the amount of desorption increases,but its desorption rate reduces.