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太行山前平原小麦/玉米轮作土壤养分状况与农田氮、磷、钾平衡分析 被引量:22
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作者 杨军芳 周晓芬 +4 位作者 孙丽敏 冯伟 杜金钟 崔瑞秀 孙苏卿 《华北农学报》 CSCD 北大核心 2011年第6期181-188,共8页
以藁城、无极、正定三个县(市)为例,分析了当前太行山前平原小麦/玉米轮作土壤养分状况与农田氮、磷、钾三要素养分平衡特征。结果表明,与第二次土壤普查相比,三县(市)土壤有机质平均含量由1.13%提高到1.86%,全氮平均含量由0.73g/kg提高... 以藁城、无极、正定三个县(市)为例,分析了当前太行山前平原小麦/玉米轮作土壤养分状况与农田氮、磷、钾三要素养分平衡特征。结果表明,与第二次土壤普查相比,三县(市)土壤有机质平均含量由1.13%提高到1.86%,全氮平均含量由0.73g/kg提高到1.14 g/kg,速效磷含量由10.3 mg/kg提高到29.83 mg/kg,速效钾含量由103.0 mg/kg提高到117.2 mg/kg,总体而言,土壤有机质虽有大幅提高,但仍然处于低水平,全氮由很低水平提高到中等水平,速效磷由中等水平提高到高水平,速效钾略有提高,处于中等水平;三县(市)农田氮、磷、钾总体均处于盈余状态,平均盈余量分别为119.8,53.5,12.2 kg/hm2,有97.5%农田的氮素、82.0%农田的磷素、63.2%农田的钾素处于盈余状态。在当前生产条件下,化肥的过量投入是导致氮、磷、钾养分盈余、积累的主要原因。 展开更多
关键词 太行山前平原 小麦/玉米轮作 土壤养分状况 、磷、平衡
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烤烟烟叶中N、K营养及N、K平衡的初步研究 被引量:4
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作者 祖艳群 林克惠 《西北植物学报》 CAS CSCD 2000年第5期831-834,共4页
研究了滇中地区烤烟中部叶片旺长期 (移栽后 60~ 65d) N、K营养及 N、K平衡。结果表明 :( 1 )烟叶一般 N含量为 2 .5%~ 4% ,K含量为 1 %~ 3% ,N/K比为 2 .5~ 3.5。 ( 2 )烟叶 N含量 >4% ,就有 N过剩的症状产生。 ( 3)烟叶 N含量 ... 研究了滇中地区烤烟中部叶片旺长期 (移栽后 60~ 65d) N、K营养及 N、K平衡。结果表明 :( 1 )烟叶一般 N含量为 2 .5%~ 4% ,K含量为 1 %~ 3% ,N/K比为 2 .5~ 3.5。 ( 2 )烟叶 N含量 >4% ,就有 N过剩的症状产生。 ( 3)烟叶 N含量 <2 .5% ,K含量 <1 % ,就表现出N、K缺乏症状。 ( 4 )烟叶 N/K比失调 ,过高或过低 ,都会影响烟株正常生长。 展开更多
关键词 烟叶 营养 营养 氮钾平衡 烤烟
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Spatial and Temporal Variability of N, P and K Balances for Agroecosystems in China 被引量:52
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作者 SHENRun-Ping SUNBo ZHAOQi-Guo 《Pedosphere》 SCIE CAS CSCD 2005年第3期347-355,共9页
Nitrogen, phosphorus, and potassium balances for agroecosystems in China from 1993 to 2001 were calculated at national and provincial levels using statistical data and related parameters, and their spatial and tempora... Nitrogen, phosphorus, and potassium balances for agroecosystems in China from 1993 to 2001 were calculated at national and provincial levels using statistical data and related parameters, and their spatial and temporal variabilities were analyzed with GIS to estimate the potential impacts of nutrient N, P and K surpluses or deficits to soil, water and air. At the national scale, the N and P balances from 1993 to 2001 showed a surplus, with the nitrogen surplus remaining relatively stable from 1997—2001. Although during this period the P surplus pattern was similar to N, it had smaller values and kept increasing as the use of phosphate fertilizer increased year by year. However, K was deficient from 1993 to 2001 even though from 1999 to 2001 the K deficit decreased. The spatial analysis revealed higher N surpluses in the more developed southeastern provinces and lowest in the western and northern provinces where there was less chemical fertilizer input. The serious K deficit mainly occurred in Shanghai and Beijing municipalities, Jiangsu, Zhejiang and Hubei provinces, and Xinjiang autonomous regions. For the years 1992, 1996 and 2001, N surpluses and K deficits had significant positive spatial correlations with per capita gross domestic product (GDP), per capita gross industrial output value, and per capita net income of rural households. This showed that the level of economic development played an important role on nutrient balances in the agroecosystems. 展开更多
关键词 China economic factors NPK balance spatial and temporal variability
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