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冬小麦氮肥经济效益与施肥期结构的研究 被引量:4
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作者 王秋杰 寇长林 +1 位作者 王兴仁 张福锁 《干旱地区农业研究》 CSCD 北大核心 1999年第1期29-34,共6页
1990年~1995年在河南省沙区进行多点肥料田间试验,采用正交旋转设计和单形重心设计,探讨冬小麦的氮肥效益与降水量、土壤有机质含量、有机肥和磷肥施用量的关系以及氮肥的施肥期结构。研究表明,冬小麦对氮肥的边际效益随施... 1990年~1995年在河南省沙区进行多点肥料田间试验,采用正交旋转设计和单形重心设计,探讨冬小麦的氮肥效益与降水量、土壤有机质含量、有机肥和磷肥施用量的关系以及氮肥的施肥期结构。研究表明,冬小麦对氮肥的边际效益随施肥量增加而减小,在其它因子为中等条件时,最高产量和最大肥料经济效益的施氮量分别为268kg/hm2和213kg/hm2,相应产量分别为4575kg/hm和4556kg/hm2。氮肥的边际效益随着降水量和土壤有机质含量的增加而减少,氮肥投入应向降雨量少、土壤肥力瘠薄的地区倾钭;氮肥的边际效益随着磷肥和有机肥投入量增加而增大,表明氮磷配合以及有机肥和无机肥配合是实现沙区小麦增产的关键。研究结果还表明,在有机肥和磷肥作底肥的基础上,不同生育期氮肥的优化分配比例应为越冬肥和拔节肥(或孕穗肥)各占1/2或底肥、越冬肥和拔节肥(或孕穗肥)各占1/3,其产量可达4932kg/hm2~5530kg/hm2。 展开更多
关键词 氮肥 冬小麦 经济效益 施肥期结构 河南
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Bacterial Community Structure and Diversity in a Black Soil as Affected by Long-Term Fertilization 被引量:46
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作者 WEI Dan YANG Qian +4 位作者 ZHANG Jun-Zheng WANG Shuang CHEN Xue-Li ZHANG Xi-Lin LI Wei-Qun 《Pedosphere》 SCIE CAS CSCD 2008年第5期582-592,共11页
Black soil (Mollisol) is one of the main soil types in northeastern China. Biolog and polymerase chain reactiondenaturing gradient gel electrophoresis (PCR-DGGE) methods were used to examine the influence of vario... Black soil (Mollisol) is one of the main soil types in northeastern China. Biolog and polymerase chain reactiondenaturing gradient gel electrophoresis (PCR-DGGE) methods were used to examine the influence of various fertilizer combinations on the structure and function of the bacterial community in a black soil collected from Harbin, Heilongjiang Province. Biolog results showed that substrate richness and catabolic diversity of the soil bacterial community were the greatest in the chemical fertilizer and chemical fertilizer+manure treatments. The metabolic ability of the bacterial community in the manure treatment was similar to the control. DGGE fingerprinting indicated similarity in the distribution of most 16S rDNA bands among all treatments, suggesting that microorganisms with those bands were stable and not influenced by fertilization. However, chemical fertilizer increased the diversity of soil bacterial community. Principal com- ponent analysis of Biolog and DGGE data revealed that the structure and function of the bacterial community were similar in the control and manure treatments, suggesting that the application of manure increased the soil microbial population, but had no effect on the bacterial community structure. Catabolic function was similar in the chemical fertilizer and chemical fertilizer+manure treatments, but the composition structure of the soil microbes differed between them. The use of chemical fertilizers could result in a decline in the catabolic activity of fast-growing or eutrophic bacteria. 展开更多
关键词 bacteria community black soil chemical fertilizer DIVERSITY MANURE
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