Iron source affects iron reduction and re‐greening of kiwifruit(Actinidia deliciosa)leaves

This study reconstructs the depositional conditions of ironstones within the Chulym-Yenisey basin and assesses the iron source. The detrital minerals of the studied deposits include quartz and feldspar. The authigenic minerals are goethite, siderite, aragonite, dolomite, calcite, apatite, barite, and pyrite. The clay components include minerals of the chlorite group (possible chamosite), nontronite, kaolinite, illite, and beidellite. Local bacterial sulfate reduction led to the formation of pyrite framboids in siltstone layers. The subsequent diagenetic iron reduction promoted the formation of chamosite from siderite. The goethite precipitation occurred in an oxidic aqueous environment. The Cretaceous continental sediments of the Ilek and Kia Formations of the Chulym-Yenisei depression consist of fine- and medium-grained, cross-stratified, poorly sorted litho-feldspatho-quartzose sandstones of fluvial channel origin alternating with bluish-gray siltstones and ironstones of floodplain–lacustrine–bog origin. Thin layers of iron-bearing rocks within siltstones formed in meromictic waters. The changes in geochemical proxies demonstrate fluctuations of paleoenvironmental conditions within the Cretaceous sequence. Siltstones and sandstones formed under humid and arid conditions, respectively. The primary iron source for sediments of the Chulym-Yenisey depression was determined as volcanogenic and igneous rocks of the Altai-Sayan mountainous region.

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Effect of Dissimilatory Iron Reduction on the Reduction of CH4Production in Landfill Conditions

Journal of Chemistry ◽

10.1155/2019/5163132 ◽

2019 ◽

Vol 2019 ◽

pp. 1-10

Author(s):

Lifang Hu ◽

Yuyang Long ◽

Chengran Fang

Keyword(s):

Iron Reduction ◽

Organic Matrix ◽

Anaerobic Incubation ◽

Mineralization Process ◽

Iron Source ◽

Organic Solid Waste ◽

Organic Solid ◽

Dissimilatory Iron Reduction ◽

Simulated Landfill ◽

Iron Forms

A high solid anaerobic incubation system was used to study the effect of dissimilatory iron reduction on the inhibition of methanogenesis in a landfill. Different iron sources including FeC6H5O7, Fe2(SO4)3, Fe2O3, and Fe0were studied. The different iron sources significantly affected the methanogenesis process in the simulated landfill system. FeC6H5O7and Fe2(SO4)3inhibited methanogenesis but Fe0and Fe2O3increased it. The dissimilatory iron reduction with FeC6H5O7as the iron source demonstrates an anaerobic mineralization process, which enhances the biodegradation but inhibits methanogenesis. The highest rate of reduction of CH4production (51.9%) was obtained at a dosage rate of 16,000 mg·kg−1, which corresponded to a reduction of 0.86 g of CH4per kg of organic matrix. Active inhibition by methanogens using both the hydrogenotrophic and acetoclastic pathways is considered to be the main mechanism underlying the reduction of CH4production by dissimilatory iron reduction with FeC6H5O7as the iron source. This is the first report on the effect of different iron forms on the reduction of CH4production during landfilling with organic solid waste.

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