文献类型： 外文期刊

作者： Lu, Dianjun ¹ ; Huan, Weiwei ² ; Yan, Taotao ¹ ; Wang, Yiliu ¹ ; Jiang, Chaoqiang ³ ; Zhang, Xiang ⁴ ; Chen, Xiaoqin ¹ ;

作者机构： 1.Chinese Acad Sci, State Key Lab Soil & Sustainable Agr, Inst Soil Sci, Nanjing 21008, Jiangsu, Peoples R China

2.Northeast Agr Univ, Coll Resources & Environm Sci, Harbin 150030, Heilongjiang, Peoples R China

3.Anhui Acad Agr Sci, Tobacco Res Ctr, Hefei 230031, Anhui, Peoples R China

4.Henan Acad Agr Sci, Inst Plant Nutr & Resource Environm, Zhengzhou 450002, Henan, Peoples R China

关键词： Nicotiana tabacum;plant-available K;placement;space heterogeneity

期刊名称：JOURNAL OF PLANT NUTRITION AND SOIL SCIENCE （ 影响因子：2.426； 五年影响因子：3.029 ）

ISSN： 1436-8730

年卷期： 2017 年 180 卷 6 期

页码：

收录情况： SCI

摘要： The high potassium (K)-fixing capacity of calcareous soils with homogeneous K supply limits crop K concentration. The objective of this study was to determine the increase in the leaf K concentration of tobacco (Nicotiana tabaccum L.) with a heterogeneous K supply. Two field experiments were conducted from 2013 to 2015 with five K rates applied in homogeneous environments and one K rate applied in varying fractions of soil volume (from 0% to 100%) in heterogeneous environments. Under ridge culture, leaf biomass was not significantly affected by homogeneous (K rate) or heterogeneous (patch size) K management. Under homogeneous conditions, increasing the K supply to three times the standard rate used by farmers (249 kg K ha(-1)) increased leaf K concentration significantly, but the effect was limited and not cost-effective. Heterogeneous supply of K fertilizer at the standard K rate in patches of 0-40% of soil volume outperformed homogeneous K supply in terms of leaf K concentrations. Furthermore, K fertilizer mixed in intermediate soil volume fractions of 1-20% resulted in higher leaf K concentrations than the smallest (0%) and larger (30-40%) soil fractions. However, such K-rich patch application should be managed precisely with specific placement due to the sharp reduction in available K with increasing distance from the fertilizer. To maximize the sorption of immobile K, the match between the uptake volume of the rhizosphere and the area available for K diffusion is important.