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Nitrogen Recommendations for Summer Maize in Northern China Using the N_min Test and Rapid Plant Tests 被引量:6
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作者 LIUXue-Jun JUXiao-Tang +2 位作者 CHENXin-Ping ZHANGFu-Suo V.ROMHELD 《Pedosphere》 SCIE CAS CSCD 2005年第2期246-254,共9页
A field experiment with a split-plot design was carried out at Dongbeiwang Farm in Beijing Municipality to establish reliable N fertilizer recommendation indices for summer maize (Zea mays L.) in northern China using ... A field experiment with a split-plot design was carried out at Dongbeiwang Farm in Beijing Municipality to establish reliable N fertilizer recommendation indices for summer maize (Zea mays L.) in northern China using the soil Nmin (mineral N) test as well as the plant nitrate and SPAD (portable chlorophyll meter readings) tests. The results showed that Nmin sollwert (NS) 60 kg N ha-1 at the third leaf stage and N rate of 40 to 120 kg N ha-1 at the tenth leaf stage could meet the N requirement of summer maiz… 展开更多
关键词 n balance n recommendation soil and plant tests Zea mays L
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Evaluation of a model recommended for N fertilizer application in irrigated rice
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作者 ZHENG Zhiming, YAN Lijiao, and WANG Zhaoqian, Agro-ecology Inst, ZheJiang Agri Univ, Hangzhou 310029, China 《Chinese Rice Research Newsletter》 1997年第3期7-8,共2页
The response of rice to N fertilizer applicationhas shown that high rates of N application donot always ensure a proportional increase inyield due to high N losses. A model, ORYZA-0 was developed by ten Berge for desi... The response of rice to N fertilizer applicationhas shown that high rates of N application donot always ensure a proportional increase inyield due to high N losses. A model, ORYZA-0 was developed by ten Berge for designingoptimum N fertilizer management strategy inrice. We evaluated the performance ofORYZA-0 in Jinhua, Zhejiang Province. ORYZA-0 includes N uptakes, partition-ing of N among the organs, and utilization ofleaf N in converting solar energy to dry mat-ter. It can predict the amount and time of Nfertilizer application to achieve a maximumbiomass or yield combining with Price algo-rithm optimization procedure. 展开更多
关键词 Evaluation of a model recommended for n fertilizer application in irrigated rice
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Evaluating the Validity of a Nitrate Quick Test in Different Chinese Soils
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作者 YUE Xian-Lu LI Fei +4 位作者 HU Yun-Cai ZHANG Huai-Zhi JI Hong-Jie ZHANG Wei-Li U. SCHMIDHALTER 《Pedosphere》 SCIE CAS CSCD 2012年第5期623-630,共8页
Because laboratory tests are expensive and time-consuming and may not be available to farmers, soil nitrate quick tests are required for optimal nitrogen management strategies in China to increase nitrogen use efficie... Because laboratory tests are expensive and time-consuming and may not be available to farmers, soil nitrate quick tests are required for optimal nitrogen management strategies in China to increase nitrogen use efficiency and to reduce nitrogen losses. A total of 328 soil samples were collected at different soil depths from 225 sites in China, which covered a wide range of climatic and geographic regions, soil types, croplands and soil textures, to evaluate the suitability of a quick reflectometer test method for analysing soil NO3-N in a wide range of soil NO3 concentrations, soil types and cropping systems in China, mainly by comparison of soil NO3-N assessed by a quick-test method (a reflectometer) and a standard laboratory method, i.e., high-performance liquid chromatography (HPLC). The reflectometer showed excellent agreement with the laboratory HPLC method with regard to soil nitrate contents for all analysed soil samples. The linear regression had slopes of 1 ± 0.08 and intercepts of ± 1.38 mg NO(-,3)-N L^(-1) among different soil types and croplands. Compared with the 1:1 lines, the regression analysis for each soil type showed statistically significant but small differences in slope; the relative difference between the values measured using the two analytical systems varied from -8% to 6%, and there were no differences in intercept except for paddy soil. The reflectometer showed adequate, statistically significant precision in determining soil nitrate contents, and it could therefore be directly used instead of the laboratory methods for soil NO(-,3)-N measurement in China. 展开更多
关键词 DILUTIOn n recommendation nitrate test strip REFLECTOMETER soil nO(3 -)-n
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