为合理、安全利用微咸水,促进番茄高效可持续生产,以京番301为试验材料,采用沙土槽培、单因素完全随机区组试验,以微咸水(EC=3 m S/cm)直接灌溉为对照,研究了微咸水不同灌溉方式对坐果期、盛果期、盛果后期番茄植株根、茎、叶及不同生...为合理、安全利用微咸水,促进番茄高效可持续生产,以京番301为试验材料,采用沙土槽培、单因素完全随机区组试验,以微咸水(EC=3 m S/cm)直接灌溉为对照,研究了微咸水不同灌溉方式对坐果期、盛果期、盛果后期番茄植株根、茎、叶及不同生育期果实中矿质元素含量的影响。结果表明:(1)番茄植株根、茎、叶及果实中的10种矿质元素含量在生育期内呈规律性的变化,根、茎、叶中6种大量矿质元素含量均为N、K、Ca大于P、Mg、Na,4种微量元素含量以Fe、Mn较高,Zn次之,Cu最低;除K外,幼果期果实中5种大量矿质元素含量最高,K在成熟期果实中含量最高,果实中微量元素含量以Fe、Zn较高,Cu和Mn较低。果实中K含量与其余9种矿质元素含量存在一定的增效作用,而Mg与Zn、Cu、P 3种元素,Na、Mn与Fe、Zn、Cu、P 4种元素间存在一定的拮抗作用。(2)微咸水参与灌溉提高了番茄植株各部位及品质形成期果实中全Na的含量,以微咸水直接灌溉提高幅度最大。与淡水灌溉相比,微咸水直接灌溉植株各部位全N含量也有所提高,但不利于果实对N、P和4种微量元素的吸收与积累。淡水灌溉有利于提高植株各部位全效P、K及Zn的含量,进而促进果实对N、P、K及Fe、Zn的吸收与积累。微咸水淡水按生育期轮灌可提高植株各部位Ca、Mg、Fe的含量,微咸水淡水按次轮灌和按生育期轮灌下幼果期、成熟期果实中Ca、Mg含量也较高。混合水灌溉和按次轮灌植株各部位Cu和Mn含量较高,因此品质形成期混合水灌溉下果实中Cu含量、按次轮灌下果实中Mn含量也较高。综上,短期微咸水灌溉或降低微咸水的矿化度灌溉(轮灌、混合水灌溉)不仅能够节约淡水资源,而且可以有效避免微咸水直接灌溉对植株生长的不利影响,并补充植物所需的N、Ca、Mg、Fe、Mn、Cu等营养元素。展开更多
Various calibration methods have been propounded to determine profiles of apparent bulk soil electrical conductivity (ECa) and soil electrical conductivity of a saturated soil paste extract (ECe) or a 1:5 soil water e...Various calibration methods have been propounded to determine profiles of apparent bulk soil electrical conductivity (ECa) and soil electrical conductivity of a saturated soil paste extract (ECe) or a 1:5 soil water extract (EC1:5) using an electromagnetic induction instrument (EM38). The modeled coefficients, one of the successful and classical methods hitherto, were chosen to calibrate the EM38 measurements of the inverted salinity profiles of characteristic coastal saline soils at selected sites of Xincao Farm, Jiangsu Province, China. However, this method required three parameters for each depth layer. An integration approach, based on an exponential decay profile model, was proposed and the model was fitted to all the calibration sites. The obtained model can then be used to predict EC1:5 at a certain depth from electromagnetic measurements made using the EM38 device positioned in horizontal and vertical positions at the soil surface. This exponential decay model predicted the EC1:5 well according to the results of a one-way analysis of variance, and the further comparison indicated that the modeled coefficients appeared to be slightly superior to, but not statistically different from, this exponential decay model. Nevertheless, this exponential decay model was more significant and practical because it depended on less empirical parameters and could be used to perform point predictions of EC1:5 continuously with depth.展开更多
文摘为合理、安全利用微咸水,促进番茄高效可持续生产,以京番301为试验材料,采用沙土槽培、单因素完全随机区组试验,以微咸水(EC=3 m S/cm)直接灌溉为对照,研究了微咸水不同灌溉方式对坐果期、盛果期、盛果后期番茄植株根、茎、叶及不同生育期果实中矿质元素含量的影响。结果表明:(1)番茄植株根、茎、叶及果实中的10种矿质元素含量在生育期内呈规律性的变化,根、茎、叶中6种大量矿质元素含量均为N、K、Ca大于P、Mg、Na,4种微量元素含量以Fe、Mn较高,Zn次之,Cu最低;除K外,幼果期果实中5种大量矿质元素含量最高,K在成熟期果实中含量最高,果实中微量元素含量以Fe、Zn较高,Cu和Mn较低。果实中K含量与其余9种矿质元素含量存在一定的增效作用,而Mg与Zn、Cu、P 3种元素,Na、Mn与Fe、Zn、Cu、P 4种元素间存在一定的拮抗作用。(2)微咸水参与灌溉提高了番茄植株各部位及品质形成期果实中全Na的含量,以微咸水直接灌溉提高幅度最大。与淡水灌溉相比,微咸水直接灌溉植株各部位全N含量也有所提高,但不利于果实对N、P和4种微量元素的吸收与积累。淡水灌溉有利于提高植株各部位全效P、K及Zn的含量,进而促进果实对N、P、K及Fe、Zn的吸收与积累。微咸水淡水按生育期轮灌可提高植株各部位Ca、Mg、Fe的含量,微咸水淡水按次轮灌和按生育期轮灌下幼果期、成熟期果实中Ca、Mg含量也较高。混合水灌溉和按次轮灌植株各部位Cu和Mn含量较高,因此品质形成期混合水灌溉下果实中Cu含量、按次轮灌下果实中Mn含量也较高。综上,短期微咸水灌溉或降低微咸水的矿化度灌溉(轮灌、混合水灌溉)不仅能够节约淡水资源,而且可以有效避免微咸水直接灌溉对植株生长的不利影响,并补充植物所需的N、Ca、Mg、Fe、Mn、Cu等营养元素。
基金Project supported by the Knowledge Innovation Program of the Chinese Academy of Sciences (No. KZCX2-YW-406-3)the National Key Basic Research Support Foundation (NKBRSF) of China (No. 2005CB121108).
文摘Various calibration methods have been propounded to determine profiles of apparent bulk soil electrical conductivity (ECa) and soil electrical conductivity of a saturated soil paste extract (ECe) or a 1:5 soil water extract (EC1:5) using an electromagnetic induction instrument (EM38). The modeled coefficients, one of the successful and classical methods hitherto, were chosen to calibrate the EM38 measurements of the inverted salinity profiles of characteristic coastal saline soils at selected sites of Xincao Farm, Jiangsu Province, China. However, this method required three parameters for each depth layer. An integration approach, based on an exponential decay profile model, was proposed and the model was fitted to all the calibration sites. The obtained model can then be used to predict EC1:5 at a certain depth from electromagnetic measurements made using the EM38 device positioned in horizontal and vertical positions at the soil surface. This exponential decay model predicted the EC1:5 well according to the results of a one-way analysis of variance, and the further comparison indicated that the modeled coefficients appeared to be slightly superior to, but not statistically different from, this exponential decay model. Nevertheless, this exponential decay model was more significant and practical because it depended on less empirical parameters and could be used to perform point predictions of EC1:5 continuously with depth.
