Effects Of Applying Zinc On The Soil Nutrient And Spring Maize Growth Under Straw Application

In recent years,with the increase in the application rate of NPK fertilizers and the continuous increase in grain yield,the supply of trace elements in soil has begun to appear relatively insufficient,and has become a limiting factor for further growth of grain production.Corn is a sensitive crop for zinc,and the application of zinc fertilizer can significantly increase corn yield.In this paper,the effects of applying zinc fertilizer on soil nutrients,the absorption and distribution of nitrogen,phosphorus,potassium and zinc in spring maize,and the effects on yield and dry matter of spring maize were studied by means of straw returning to the field with zinc fertilizer.The changes of adsorption and desorption characteristics of zinc in soils of several main cultivated land in Jilin Province under straw fertilization were discussed.The main findings are as follows:1.Effects of Straw Returning and Zinc Fertilizer on Soil NutrientsZinc application could significantly increase the soil available zinc content during the growth period of spring maize.At the maturity stage,the soil available zinc content was 64%higher than that without zinc application,and the total zinc content was increased by 3.37%.The soil available zinc content could be further increased by applying straw and zinc fertilizer.The soil available nitrogen,phosphorus and potassium content could be increased by returning straw,but the soil available nitrogen,phosphorus and potassium content could not be significantly affected by applying zinc alone.2.Effect of Straw Fertilization on Zinc Adsorption and Desorption in Soils of Main Cultivated Land in Jilin ProvinceStraw fertilization can increase the adsorption capacity of five kinds of soils in varying degrees,and the adsorption capacity of black soil increases the most,alluvial soil increases the largest proportion.The total adsorption capacity of zinc in five main dry land soils in Jilin Province is black soil>black calcareous soil>white pulp soil>light calcareous soil>alluvial soil.The adsorption can be described by Langmuir,Freundlich and Temkin equations,and the correlation coefficient reaches a very significant level.Straw fertilization also increased the amount of zinc desorption in five soils to varying degrees,and reduced zinc fixation in soils.3.Effects of straw returning and zinc fertilizer on nutrient uptake and distribution of Spring MaizeThe accumulation of nutrients in spring maize plants could be promoted by applying zinc fertilizer with straw returning.The accumulation of nitrogen,phosphorus,potassium and zinc in straw returning with zinc fertilizer treatment was38.37%,23%,17.2%and 31.68%higher than that in straw-free zinc fertilizer treatment,respectively.However,there was no significant effect on the distribution of nutrients in different organs.The application of zinc fertilizer combined with straw returning also increased the transfer and distribution of nitrogen,phosphorus,potassium and zinc from vegetative organs to grains,thereby increasing the nutrient content in grains.The content of nitrogen,phosphorus,potassium and zinc in grains increased 32.7%,26%,47.4%and 32.61%respectively in straw returning and zinc fertilizer application treatments compared with those in straw-free and zinc-free treatments.4.Effects of Straw Returning and Zinc Fertilizer Application on Yield and Dry Matter Accumulation of Spring MaizeUnder the experimental conditions,the yield of zinc treatment increased by14.1%compared with that of non-zinc treatment when no straw was returned to the field.When straw was returned to the field,the yield of zinc treatment increased by17.3%compared with that of non-zinc treatment.Under the condition of no straw returning,the dry matter weight increased by 11.5%compared with that without zinc application,and 14.1%under the condition of straw returning,the dry matter weight increased by zinc application compared with that without zinc application.The dry matter accumulation of straw combined with zinc fertilizer reached the highest of22077 kg/hm~2.In conclusion,zinc application can significantly increase soil available zinc and total zinc content,and straw returning combined with zinc fertilizer can further increase soil available zinc content.Straw fertilization improves the adsorption and desorption capacity of zinc in soil,reduces the fixed amount of zinc in soil,and thus improves the effectiveness of zinc in soil.Straw returning combined with zinc fertilizer can effectively promote the absorption and accumulation of nitrogen,phosphorus,potassium,zinc and other nutrients in spring maize,at the same time improve the transfer and distribution of nutrients,and ultimately increase the yield and dry matter accumulation of spring maize.