Rational application of different forms of nitrogen（N） fertilizer for peanut（Arachis hypogaea L.） requires tracking the N supplied sources which are commonly not available in the differences among the three source...Rational application of different forms of nitrogen（N） fertilizer for peanut（Arachis hypogaea L.） requires tracking the N supplied sources which are commonly not available in the differences among the three sources：root nodule,soil and fertilizer.In this study,two kinds of peanut plants（nodulated variety（Huayu 22） and non-nodulated variety（NN-1）） were choosed and four kinds of N fertilizers：urea-N（CONH_2-N）,ammonium-N（NH_4~＋-N）,nitrate-N（NO_3^--N） and NH_4~＋ ＋NO_3^--N labeled by^（15）N isotope were applied in the field barrel experiment in Chengyang Experimental Station,Shandong Province,China,to determine the N supplied sources and N use efficiency over peanut growing stages.The results showed that intensities and amounts of N supply from the three sources were all higher at middle growing stages（pegging phase and podding phase）.The accumulated amounts of N supply from root nodule,soil and fertilizer over the growing stages were 8.3,5.3 and 3.8g m^（-2） in CONH_2-N treatment,which are all significantly higher than in the other three treatments.At seedling phase,soil supplied the most N for peanut growth,then root nodule controlled the N supply at pegging phase and podding phase,but soil mainly provided N again at the last stage（pod filling phase）.For the whole growing stages,root nodule supplied the most N（47.8 and 43.0%） in CONH_2-N and NH_4~＋-N treatments,whereas soil supplied the most N（41.7 and 40.9%） in NH_4~＋ ＋NO_3^--N and NO_3^--N treatments.The N use efficiency was higher at pegging phase and podding phase,while accumulated N use efficiency over the growing stages was higher in CONH_2-N treatment（42.2%） than in other three treatments（30.4%in NH_4~＋-N treatment,29.4%in NO_3^--N treatment,29.4%in NH_4~＋ ＋NO_3^--N treatment）.In peanut growing field,application of CONH_2-N is a better way to increase the supply of N from root nodule and improve the N use efficiency.展开更多
Fate of urea nitrogen (N) applied to rape grown on a red soil was investigated by the ￣(15)N mass balancetechnique, and efficiency of urea and effect of nutrients balance in raising rape yield were investigated ina f...Fate of urea nitrogen (N) applied to rape grown on a red soil was investigated by the ￣(15)N mass balancetechnique, and efficiency of urea and effect of nutrients balance in raising rape yield were investigated ina field plot experiment. One hundred and thirty-eight kg N/ha, 86 kg N/ha as basal dressing and 52 kgN/ha as top dressing, was applied with band application technique. The experiment was conducted in thesoutheast of China, near Yingtan City, Jianxi Province.Results from is￣(15)N mass balance study showed that when urea was applied as basal dressing the plantrecovery was 44.0% of the applied N for Theatment T (with application of N, P, K, B and lime). Plantrecoveries were 38.0%-40.5% for Treatments -K, -B, -lime and +RS (without application of K, B or limeas well as with additional rice straw compared with Theatment T), which were not significantly differentfrom Treatment T. In contrast, plant recovery was only 5.1% for Treatment-P (without application of P),indicating that P was the factor limiting N uptake by rape. However, N remaining in 0-0.30 m soil was highup to 71.6% for Theatment -P, while the corresponding data were 33.0%-42.6% for the other treatments.The total recovery of applied N (including plant recovery and N remaining in 0-0.60 m soil) was 91.5% forTreatment T when urea was applied as basal dressing, while almost all the applied N was recovered when ureawas applied as top dressing. It was suggested that N loss was greatly controlled by using band applicationmethod in this experiment.Results from the field plot experiment showed that N supply capacity of this red soil was very low, andthe efficiency of the applied N was quite high, 7.1 kg rape seed was increased by application of one kg N forTreatmentT. Nitrogen and phosphorus were the key factors limiting rape yield, and the yield was very lowwhen neither of them was applied. The yield in TreatmentK was significantly lower than that in TYeatmentT, with the former accounting for 77% of the later.展开更多
The need to accurately estimate gaseous nitrogen losses from soils is required to have a better understanding of the processes involved as well as soil and environmental conditions, and management practices contributi...The need to accurately estimate gaseous nitrogen losses from soils is required to have a better understanding of the processes involved as well as soil and environmental conditions, and management practices contributing to these emissions. The objective was to quantify the denitrification rate using undisturbed cores with acetylene, as related to nitrogen (N) fertilization rate in a spring wheat crop (Triticum aestivum L.) under conventional tillage. Soil denitrification losses remained low throughout most of the growing season, when water-filled pore space (WFPS) was below 60%, ranging from 0.79 to 447.3 g N2O-N ha-1•day-1 in the fertilized plot and was less than 47.3 g N2O-N ha-1•day-1 in the control. Denitrification rates were the highest when N fertilizer was applied after frequent and intensive rain. A good correlation was found between the logarithm of the daily denitrification rate and WFPS (r = 0.67, n = 90);however the NO3-N concentration was not a good indicator (r = 0.21, n = 90). Cumulative N2O-N losses by denitrification averaged 3.5 and 0.9 kg N2O-N ha-1 in the fertilized and unfertilized treatment, respectively, during a period of 4 months this difference was not significant. Most N2O-N losses occurred early in the spring;therefore sampling schedules need to focus on this period.展开更多
基金supported by the Youth Scientific Research Foundation of Shandong Academy of Agricultural Sciences, China(2014QNM27)the Applying Basic Research Project of Qingdao,Shandong Province,China(14-2-4-90-jch)+3 种基金the Modern Agricultural Industry Technology System,China (SDAIT-05-021-04)the National Key Technology R&D Program of China(2014BAD11B04)the Key Innovation of Science and Technology Project of Shandong Academy of Agricultural Sciences,China(2014CXZ06-22014CXZ11-2)
文摘Rational application of different forms of nitrogen（N） fertilizer for peanut（Arachis hypogaea L.） requires tracking the N supplied sources which are commonly not available in the differences among the three sources：root nodule,soil and fertilizer.In this study,two kinds of peanut plants（nodulated variety（Huayu 22） and non-nodulated variety（NN-1）） were choosed and four kinds of N fertilizers：urea-N（CONH_2-N）,ammonium-N（NH_4~＋-N）,nitrate-N（NO_3^--N） and NH_4~＋ ＋NO_3^--N labeled by^（15）N isotope were applied in the field barrel experiment in Chengyang Experimental Station,Shandong Province,China,to determine the N supplied sources and N use efficiency over peanut growing stages.The results showed that intensities and amounts of N supply from the three sources were all higher at middle growing stages（pegging phase and podding phase）.The accumulated amounts of N supply from root nodule,soil and fertilizer over the growing stages were 8.3,5.3 and 3.8g m^（-2） in CONH_2-N treatment,which are all significantly higher than in the other three treatments.At seedling phase,soil supplied the most N for peanut growth,then root nodule controlled the N supply at pegging phase and podding phase,but soil mainly provided N again at the last stage（pod filling phase）.For the whole growing stages,root nodule supplied the most N（47.8 and 43.0%） in CONH_2-N and NH_4~＋-N treatments,whereas soil supplied the most N（41.7 and 40.9%） in NH_4~＋ ＋NO_3^--N and NO_3^--N treatments.The N use efficiency was higher at pegging phase and podding phase,while accumulated N use efficiency over the growing stages was higher in CONH_2-N treatment（42.2%） than in other three treatments（30.4%in NH_4~＋-N treatment,29.4%in NO_3^--N treatment,29.4%in NH_4~＋ ＋NO_3^--N treatment）.In peanut growing field,application of CONH_2-N is a better way to increase the supply of N from root nodule and improve the N use efficiency.
文摘Fate of urea nitrogen (N) applied to rape grown on a red soil was investigated by the ￣(15)N mass balancetechnique, and efficiency of urea and effect of nutrients balance in raising rape yield were investigated ina field plot experiment. One hundred and thirty-eight kg N/ha, 86 kg N/ha as basal dressing and 52 kgN/ha as top dressing, was applied with band application technique. The experiment was conducted in thesoutheast of China, near Yingtan City, Jianxi Province.Results from is￣(15)N mass balance study showed that when urea was applied as basal dressing the plantrecovery was 44.0% of the applied N for Theatment T (with application of N, P, K, B and lime). Plantrecoveries were 38.0%-40.5% for Treatments -K, -B, -lime and +RS (without application of K, B or limeas well as with additional rice straw compared with Theatment T), which were not significantly differentfrom Treatment T. In contrast, plant recovery was only 5.1% for Treatment-P (without application of P),indicating that P was the factor limiting N uptake by rape. However, N remaining in 0-0.30 m soil was highup to 71.6% for Theatment -P, while the corresponding data were 33.0%-42.6% for the other treatments.The total recovery of applied N (including plant recovery and N remaining in 0-0.60 m soil) was 91.5% forTreatment T when urea was applied as basal dressing, while almost all the applied N was recovered when ureawas applied as top dressing. It was suggested that N loss was greatly controlled by using band applicationmethod in this experiment.Results from the field plot experiment showed that N supply capacity of this red soil was very low, andthe efficiency of the applied N was quite high, 7.1 kg rape seed was increased by application of one kg N forTreatmentT. Nitrogen and phosphorus were the key factors limiting rape yield, and the yield was very lowwhen neither of them was applied. The yield in TreatmentK was significantly lower than that in TYeatmentT, with the former accounting for 77% of the later.
文摘The need to accurately estimate gaseous nitrogen losses from soils is required to have a better understanding of the processes involved as well as soil and environmental conditions, and management practices contributing to these emissions. The objective was to quantify the denitrification rate using undisturbed cores with acetylene, as related to nitrogen (N) fertilization rate in a spring wheat crop (Triticum aestivum L.) under conventional tillage. Soil denitrification losses remained low throughout most of the growing season, when water-filled pore space (WFPS) was below 60%, ranging from 0.79 to 447.3 g N2O-N ha-1•day-1 in the fertilized plot and was less than 47.3 g N2O-N ha-1•day-1 in the control. Denitrification rates were the highest when N fertilizer was applied after frequent and intensive rain. A good correlation was found between the logarithm of the daily denitrification rate and WFPS (r = 0.67, n = 90);however the NO3-N concentration was not a good indicator (r = 0.21, n = 90). Cumulative N2O-N losses by denitrification averaged 3.5 and 0.9 kg N2O-N ha-1 in the fertilized and unfertilized treatment, respectively, during a period of 4 months this difference was not significant. Most N2O-N losses occurred early in the spring;therefore sampling schedules need to focus on this period.
