| In recent years,China has become the world’s largest fertilizer consumer,but the fertilizer utilization efficiency is lower than the international average.On the one hand,the abuse of chemical fertilizers has caused a series of serious ecological problems such as soil quality degradation and environmental pollution.On the other hand,straw Such agricultural waste lacks a reasonable resource utilization method,which is not conducive to the sustainable development of China’s agriculture.Biochar is a carbon-rich black solid particle obtained by pyrolysis of biomass materials such as straw,and is also rich in a large amount of nutrients.Returning straw biochar to the field can improve soil structure and enhance soil fertility.It provides a new solution for the reduction of fertilizer application and the utilization of straw resources in my country.Although biochar has shown its broad application prospects,the technical approaches for the combined application of biomass charcoal and chemical fertilizers,the effects of biomass charcoal-formulation fertilization,and the potential and economic feasibility of biomass charcoal in replacing fertilizers are still lacking systematic data support.Based on this,this paper takes corn in Yanghuang Irrigation Area as the research object,deeply studies the effects of biomass carbon on nitrogen and carbon reduction,continuous carbon-based fertilizer return to the field and soil improvement and compares the main fertilization technology to evaluate the effectiveness of the carbon-based fertilizer.,Use and promotion provide theoretical basis,the main research results are as follows:1.Compared with the conventional fertilization year-on-year,under the condition of equal amount of biomass carbon input,with the increase of nitrogen reduction ratio,corn root growth,plant height and stem thickness,chlorophyll SPAD value and net photosynthetic rate showed a significant decrease trend.The growth and development of maize roots and plants,and leaf photosynthesis have a significant promotion effect.The root growth index increased by 13.5%-22.9%,and the growth physiological index increased by 8.8%-15.3.Increased by 4.4%and 8.8%respectively;as the proportion of nitrogen reduction increased,corn yield decreased significantly;15%nitrogen reduction achieved a significant increase in corn yield by 15%by increasing corn ear weight and 100-kernel weight,and the economic benefits of each nitrogen reduction treatment Both are lower than conventional fertilization;the addition of straw biomass carbon can significantly improve the soil water stability of large aggregates,the number of large aggregates increases by 166.87%-82.3%;different nitrogen reduction ratios can improve soil organic matter,available phosphorus,available potassium and Alkaline-decomposed nitrogen content,of which the 15%reduction in nitrogen treatment has the best soil nutrient retention capacity,and the alkali-decomposed nitrogen content is increased by 16.24%;the appropriate carbon-nitrogen ratio input is conducive to improving soil microorganisms and enzyme activity.The content of fertilizing phosphatase and urease increased significantly by 35.9%and 6.3%,respectively,and the number of actinomycetes increased by 7.3 times.However,excessive nitrogen reduction resulted in an imbalance of carbon-to-nitrogen ratio,and the number of soil microorganisms decreased significantly;compared with conventional fertilization Reducing nitrogen by 15%significantly improved nitrogen fertilizer utilization efficiency and nitrogen fertilizer agronomic efficiency by 20.57%and 7.93kg/kg.Comprehensive analysis shows that the conventional fertilization on a year-on-year basis,under the condition of 4.5t/hm2 input of biomass carbon,reducing nitrogen by 15%is regarded as the best carbon-based inorganic application scheme.2.Compared with conventional fertilization,on the basis of 20%nitrogen reduction,the application of biochar 6.75t/hm2 has a significant promotion effect on corn root system,plant growth and development,and leaf photosynthesis.The growth of various crop root indicators has reached 45%-63.1%.Physiological indicators increased by 16%-31%;soil organic matter and available nitrogen and phosphorus nutrients increased significantly,with an increase of 43%-48%,maize yield increased significantly by 41.4%;nitrogen fertilizer utilization rate and agronomic utilization efficiency were the highest,increased by 38.02%and 18.79 kg/kg.The proportion of soil water stability large aggregates(>0.25mm)increases with the increase of biomass carbon application;the increase of biomass carbon can promote the soil microorganisms and soil enzyme activities;comprehensive analysis,nitrogen reduction 20 On the basis of%,the application of biomass charcoal 6.75t/hm2 can be regarded as the best plan of corn carbon-based inorganic compound application in Yanghuang irrigation area.3.Compared with conventional fertilization,the input of straw biomass carbon-based fertilizer has a significant effect on corn development.When the input of carbon-based fertilizer reaches 1.35t/hm2,the increase of crop root index reaches 81.3%-103.47%;The net photosynthetic rate of the leaves has a promoting effect,with an increase of 6.7%-22.3%.With the increase of the application amount of carbon-based fertilizer,the plant height,stem weight,ear weight and yield of corn showed a trend of increasing first and then decreasing with the increase of the application amount of carbon-based fertilizer;the net income of corn showed a trend of first increasing and then decreasing.One-time application of 1.35t/hm2 of carbon-based fertilizer increased income by 8.49%;the content of soil water-stable macroaggregates(>0.25mm),soil organic matter,available phosphorus and available potassium increased by 65.7%,31.2%,198%,and 14.9%The soil stability is gradually increased,and the fertility level is gradually increased;the total number of soil bacteria increased significantly by 4 times,and the soil microbial activity increased.Comprehensive analysis shows that under different input conditions of carbon-based fertilizer,the optimal response and economic benefit of maize is 1.35t/hm2.4.Compared with conventional fertilization,the input of carbon-based and organic materials can promote the growth of crop roots,speed up the photosynthesis rate of crops,increase crop yield and economic benefits.The application of carbon-based fertilizer+chemical fertilizer treatment increases the output by 13.3%and the economic benefit by 10.9%..The large particle water-stable aggregates(WSA>0.25)in the 0-20cm soil layer and 20-40cm soil layer increased significantly by 75.7%and 64%;the input of carbon-based fertilizer can significantly improve the soil alkaline nitrogen,available phosphorus and available effects compared with conventional fertilization.Potassium content 16.6%,120.67%and 65.8%,the combined application of carbon-based fertilizers and chemical fertilizers significantly increased soil organic matter,alkaline nitrogen,available phosphorus and available potassium content by 20.4%,14.6%,50.5%and 58.3%,organic fertilizers and fertilizers Fertilization significantly improved soil organic matter,alkaline nitrogen and available phosphorus by 20.7%,29.9%,and 22.7%;carbon-based fertilizers and organic fertilizers combined with chemical fertilizers were more conducive to bacterial reproduction,and the bacterial counts of conventional fertilization increased by 9.66 times and 13.63,respectively.Compared with conventional fertilization,the input of organic fertilizer significantly increased soil phosphatase,catalase and urease activities by 49%,5%and 62.9%,and the activity of carbon-based fertilizer and carbon-based fertilizer combined with urease increased by 23.07%and 59.4%.In summary,the carbon-based fertilizer applied for two consecutive years has improved soil aggregate structure,improved soil fertility level,optimized microbial community structure and activity compared with conventional fertilization.Compared with organic fertilizer,it can improve soil water stability and available phosphorus and potassium content.Promote the growth and production of crops and improve the economic benefits of crops.n summary,the improvement of biochar on soil and the promotion of crop growth are closely related to the amount of biochar and nitrogen fertilizer application.The proper carbon-nitrogen ratio can effectively improve the soil,promote crop growth and increase crop yield,but economic benefits It is always not as good as conventional fertilization.The impact of carbon-based fertilizer made of biochar and chemical fertilizer on crops and soil is also related to its application rate.When the application rate of carbon-based fertilizer is 1.35t/hm2,the effect is the best,although it is slightly inferior to other fertilizers in terms of soil improvement Organic fertilizer,but it is significantly better than other fertilization measures in promoting crop growth and increasing crop yield,and has better economic benefits and is worth promoting. |
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