• 主题
高级搜索  >
历史搜索 清空历史
首页> 外文期刊>South African Journal of Geology: Being the Transaction of the Geological Society of South African: Syndie die Verhandelinge van die Geologiese Vereniging van Suid-Afrika >Effect of synthetic amorphous and crystalline iron oxides on redox potential and exchangeable cations in wetland soils of Maputaland Kwazulu-Natal, South Africa
【24h】

Effect of synthetic amorphous and crystalline iron oxides on redox potential and exchangeable cations in wetland soils of Maputaland Kwazulu-Natal, South Africa

机译：南非马普拉德夸祖鲁 - 北北川岛湿地土壤雷控潜力及其可交换阳离子的合成无定形和晶体氧化铁对南非的影响

获取原文
获取原文并翻译 | 示例
       
页面导航
  • 摘要
  • 著录项
  • 相似文献
  • 相关主题

摘要

Some grey-coloured soils of the Maputaland Coastal Plains in northern KwaZulu-Natal do not exhibit the redox morphology normally associated with seasonal water saturation, resulting in serious limitations in using soil morphology for wetland delineation. One of the hypotheses to explain this phenomenon is that these soils simply do not contain enough iron minerals that can be reduced and re-oxidised to form redox accumulations and depletions. Alternatively, if iron minerals are present, they are too crystalline to be readily reduced as a result of the lower iron activity associated with these oxides and can only be reduced at a slow rate. This investigation aimed to determine if a deficiency in iron oxides could explain the absence of redoximorphic features in the wetland soils. A split-plot experimental design with 78 cores was set up to investigate the effect that varying iron crystallinity had on soil redox potential. The experiment was conducted in a controlled environment in the laboratory with the temperature set at 23°C with fluctuations of ±2°C. Synthetic ferrihydrite and goethite were mixed with soils (0.84 g.kg-1) and packed to a bulk density of 1.4 Mg m-3. The cores were then saturated to 73% of porosity and the pH, Eh, Ca, Mg, Fe, and Mn measured bi-weekly. The ferrihydrite and goethite treatments did not affect ammonium acetate extractable Ca and Mg. The treatments did, however, increase significantly the ammonium acetate extractable Fe, Mn, and pH, while both treatments significantly decreased pe over the 42 day extraction period. The goethite treatment reduced within five days, while ferrihydrite only reduced after 20 days. The Feo/Fed ratios for the treatments suggested that ferrihydrite started as less crystalline and increased sharply after saturation, while the crystallinity of the goethite treatment only increased slightly. Results presented here indicate that the absence of redoximorphic features in the soils of Manguzi could be attributed to
机译：夸祖鲁北部的马普拉德兰沿海平原的一些灰色土壤不表现出通常与季节性水饱和度相关的氧化还原形态，从而严重限制了利用湿地描绘的土壤形态。解释这种现象之一的假设是这些土壤根本不含足够的铁矿物，可以减少和重新氧化以形成氧化还原累积和耗尽。或者，如果存在铁矿物质，则由于与这些氧化物相关的较低的铁活性，它们是过分的才能容易地降低，并且只能以慢速降低。这种调查旨在确定氧化铁缺乏是否可以解释湿地土壤中的缺乏氧杂体特征。设立了具有78个核的分裂实验设计，探讨了不同铁结晶对土壤氧化还原潜力的影响。实验在实验室的受控环境中进行，温度设定在23℃，波动为±2℃。合成的Ferrihydrite和甲藻与土壤（0.84g.kg-1）混合，并填充到1.4mg m-3的堆积密度。然后将核心饱和至孔隙率的73％，pH，EH，Ca，Mg，Fe和Mn测量双周。 Ferrihydite和甲酸酯治疗不影响乙酸铵可提取的Ca和mg。然而，该治疗方法显着增加了乙酸铵可提取的Fe，Mn和pH，而两种治疗在42天提取期间的PE显着降低。在五天内降低的果石治疗，而Ferrihydrite仅在20天后降低。治疗的FeO /喂养比例表明，Ferrihydrite开始少得多的结晶并在饱和后急剧增加，而可甲酸酯处理的结晶度仅略微增加。此处提出的结果表明，曼古兹的土壤中没有氧化钠特征可能归因于

著录项

相似文献

  • 外文文献
  • 专利
获取原文

客服邮箱：kefu@zhangqiaokeyan.com

京公网安备：11010802029741号 ICP备案号：京ICP备15016152号-6 六维联合信息科技 (北京) 有限公司©版权所有

  • 客服微信

  • 服务号