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Optimum Application Rate of Nitrogen in Summer Peanut in Southern Shandong Area
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作者 Hongjie TANG 《Asian Agricultural Research》 2023年第3期34-36,共3页
[Objectives]To study the effect of nitrogen(N)on the growth demand of summer peanuts under a certain level of phosphorus and potassium fertilizers,and to carry out experiments on nitrogen fertilizer control of summer ... [Objectives]To study the effect of nitrogen(N)on the growth demand of summer peanuts under a certain level of phosphorus and potassium fertilizers,and to carry out experiments on nitrogen fertilizer control of summer peanuts.[Methods]Four treatments were set up in the experiment:no-nitrogen plot(N 0P_(4)K_(4)),optimized nitrogen plot(N_(7)P_(4)K_(4)),70%optimized nitrogen plot(N_(5)P_(4)K_(4)),130%optimized nitrogen plot(N 9P 4K 4),repeated 3 times,and arranged in random blocks.The area of the plot was 42 m^(2),ridges were set between the plots,and protective rows of more than 1 m were set around the experimental site.The types of fertilizers were urea,superphosphate,and imported potassium chloride,and the variety of peanuts was Linhua 5.Except for the level of fertilization,other agricultural operations were the same,and soil sampling tests,field records,and yield testing were carried out according to the requirements of the plan.[Results]On the basis of 60 kg/ha of phosphorus and potassium fertilizer application,the optimum economical fertilizer application rate and the highest application rate of pure nitrogen were about 115.20 and 131.25 kg/ha,respectively.[Conclusions]This study is expected to provide a certain basis for the high-quality and high-yield summer peanuts in southern Shandong area. 展开更多
关键词 Southern Shandong area Summer peanut Nitrogen fertilizer optimum application rate
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Determination of optimum nitrogen application rates in Zhejiang Province, China, based on rice yields and ecological security 被引量:6
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作者 LI Yan CHEN Yi +2 位作者 WU Chun-yan TANG Xu JI Xiao-jiang 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2015年第12期2426-2433,共8页
Excessive nitrogen(N) fertilization in intensive agricultural areas such as the plain region of South China has resulted in low nitrogen use efficiency and serious environmental problems. To determine the optimum N ... Excessive nitrogen(N) fertilization in intensive agricultural areas such as the plain region of South China has resulted in low nitrogen use efficiency and serious environmental problems. To determine the optimum N application rate, grain yield, apparent nitrogen recovery efficiency(ANRE), apparent N loss, and ammonium(NH_3) volatilization under different N application rates in the three years from 2012 to 2014 were studied. The results showed that the relationship between grain yields and N application rate in the three years were well fitted by quadratic equations. When N application rate reached 197 kg ha^(–1) in 2012, 199 kg ha^(–1) in 2013 and 196 kg ha^(–1) in 2014, the plateau of the grain yields appeared. With the increase of N application rate, the ANRE for rice decreased which could be expressed with sigmoidal equation; when N application rate was 305 kg ha^(–1) in 2012, 275 kg ha^(–1) in 2013 and 312 kg ha^(–1) in 2014, the curves of ANRE appeared turing points. Besides, the relationship between soil Nresidual and N application rate was fitted by the quadratic equation and the maximums of soil Nresidual were reached in the three years with the N application rate of 206, 244 and 170 kg ha^(–1), respectively. Statistical analysis indicated that NH3 volatilization and apparent N loss in three years all increased with the increasing N application rate. When the amount of NH3 volatilization increased to 11.6 kg N ha^(–1) in 2012, 40.5 kg N ha^(–1) in 2013 and 57.0 kg N ha^(–1)in 2014, the apparent N loss in the three years had obvious increase. To determine the optimum N application rate, the average N application on the plateau of the grain yield was considered as the lower limit while the average N application rate at the turning points of ANRE, the residual N in soil and apparent N loss was taken as the upper limit. According to the results in three years, the optimum N application rate for rice in Zhejiang was 197–255 kg ha^(–1). 展开更多
关键词 optimum nitrogen application rate Zhejiang rice yields ecological security
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Effectuate Application of Optimum Methods in Grinding Process
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作者 Zhu Z H Mo K W 《厦门大学学报(自然科学版)》 CAS CSCD 北大核心 2002年第S1期129-130,共2页
Random error of grinding process is central factor th at give an effect on grinding quality all through. Optimum methods are usually a pplied on grinding process for higher productivity and preferable grinding quali t... Random error of grinding process is central factor th at give an effect on grinding quality all through. Optimum methods are usually a pplied on grinding process for higher productivity and preferable grinding quali ty. But the grinding quality can’t be reliably controlled now and then while opt imal solution of grinding processing parameters have been applied in production, because of two involved aspects which are availability of established empirical formulas and reliability of setting up optimum mathematical model. That is to s ay, there is particular application of optimum methods in grinding process. This paper discussed that how to confirm conditions of grinding test which be po int to grinding peculiarity when test design and regression analysis are used to setting up some empirical formulas. In order to reduce effect of random errors on precision of the empirical formulas and enable them to be applied widely, a m ethod that a lot of random error can be sufficiently contained in grinding test was suggested. And then, A means to ameliorate restriction formulas of grinding quality is expounded based on marked level of the empirical formulas and improve d reliability of optimum mathematical model is given, which offer an effectual w ay for solving grinding quality out of control as a result of random error and w orkable optimal solution of grinding processing parameters can be applied in the production really. Finally, an example is presented. 展开更多
关键词 Effectuate application of optimum Methods in Grinding Process
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Effect Models of Nitrogen,Phosphorus and Potassium Fertilizer Formulation in Banana 被引量:1
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作者 匡石滋 田世尧 +3 位作者 李春雨 易干军 洪炎龙 万国富 《Agricultural Science & Technology》 CAS 2010年第9期130-135,共6页
[Objective] The aim was to modify the application amount of N,P and K fertilizer so as to provide a reference for establishing balanced fertilization index system of banana.[Method]The N,P and K fertilizer "3414" te... [Objective] The aim was to modify the application amount of N,P and K fertilizer so as to provide a reference for establishing balanced fertilization index system of banana.[Method]The N,P and K fertilizer "3414" test was carried out on banana,and then regression analysis was performed on the fertilizer effect.Ternary quadratic,binary quadric and one-variable quadratic regression equations for the fertilizer effect on the banana yield were constructed.[Result]Suitable amount of N,P and K fertilizer had significant yield improving effect,whereas overdose of fertilizer application led to decreasing of utilization rate of fertilizer.Therefore,suitable amount of N,P and K fertilizer should be selected in production.It could be concluded that one-variable quadratic regression equations was the best model to calculate the suitable fertilizer amount.The best yield range of banana in the tested field was 44.193-45.904 t/hm2,while the corresponding optimum application amount of N,P2O5 and K2O was 795.1,262.3 and 1 236.9 kg/hm2 respectively,and the ratio among nitrogen,phosphorus and potassium are 1∶0.33∶1.55.[Conclusion]The result in this study could provide references for the soil types similar to the tested field. 展开更多
关键词 BANANA NITROGEN Phosphorus and potassium fertilization Fertilizer application model optimum application amount
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Impacts of Salinity and Nitrogen on the Photosynthetic Rate and Growth of Sunflowers(Helianthus annuus L.) 被引量:10
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作者 ZENG Wen-Zhi XU Chi +3 位作者 WU Jing-Wei HUANG Jie-Sheng ZHAO Qiang WU Mou-Song 《Pedosphere》 SCIE CAS CSCD 2014年第5期635-644,共10页
Understanding the interactions between salinity and fertilizers is of significant importance for enhancing crop yield and fertilizeruse efficiency. In this study a complete block design experiment was performed in the... Understanding the interactions between salinity and fertilizers is of significant importance for enhancing crop yield and fertilizeruse efficiency. In this study a complete block design experiment was performed in the Hetao Irrigation District of Inner Mongolia,China, to evaluate the effects of interactions between soil salinity and nitrogen(N) application rate on sunflower photosynthesis and growth and to determine the optimum N application rate for sunflower growth in the district. Four levels of soil salinity expressed as electrical conductivity(0.33–0.60, 0.60–1.22, 1.2–2.44, and 2.44–3.95 dS m-1) and three application rates of N fertilization(90, 135,and 180 kg ha-1) were applied to 36 micro-plots. Soil salinity inhibited the photosynthetic rate, stomatal conductance, transpiration rate, plant height, leaf area, and aboveground dry matter of sunflowers. The intercellular CO2 concentration first decreased and then increased with increasing soil salinity in the seedling stage, and the instantaneous leaf water-use efficiency fluctuated with soil salinity. The stomatal and non-stomatal limitations of sunflowers alternated in the seedling stage; however, in the bud, blooming,and mature stages, the stomatal limitation was prevalent when the salinity level was lower than 2.44 dS m-1, whereas the nonstomatal limitation was predominant above the salinity level. The application of N fertilizer alleviated the adverse effects of salinity on sunflower photosynthesis and growth to some extent. During some key growth periods, such as the seedling and bud stages, a moderate N application rate(135 kg ha-1) resulted in the maximum photosynthetic rate and yielded the maximum dry matter. We suggest a moderate N application rate(135 kg ha-1) for the Hetao Irrigation District and other sunflower-growing areas with similar ecological conditions. 展开更多
关键词 non-stomatal limitation N-use efficiency optimum N application rate soil salinization stomatal limitation
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