Redox-Controlled Mobility of Arsenic and Cadmium in Paddy Soil Amended with Organic Matter, Sulfate, and Iron Oxide

Few studies have focused on the combined application of digestate and straw and its feasibility in rice production. Therefore, we conducted a two-year field experiment, including six treatments: without nutrients and straw (Control), digestate (D), digestate + fertilizer (DF), digestate + straw (DS), digestate + fertilizer + straw (DFS) and conventional fertilizer + straw (CS), to clarify the responses of rice growth and paddy soil nutrients to different straw and fertilizer combinations. Our results showed that digestate and straw combined application (i.e., treatment DFS) increased rice yield by 2.71 t ha−1 compared with the Control, and digestate combined with straw addition could distribute more nitrogen (N) to rice grains. Our results also showed that the straw decomposition rate at 0 cm depth under DS was 5% to 102% higher than that under CS. Activities of catalase, urease, sucrase and phosphatase at maturity under DS were all higher than that under both Control and CS. In addition, soil organic matter (SOM) and total nitrogen (TN) under DS and DFS were 20~26% and 11~12% higher than that under B and DF respectively, suggesting straw addition could benefit paddy soil quality. Moreover, coupling straw and digestate would contribute to decrease the N content in soil surface water. Overall, our results demonstrated that digestate and straw combined application could maintain rice production and have potential positive paddy environmental effects.

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AGGREGATION AND SURFACE PROPERTIES OF IRON OXIDE NANOPARTICLES: INFLUENCE OF pH AND NATURAL ORGANIC MATTER

Environmental Toxicology and Chemistry ◽

10.1897/07-559.1 ◽

2008 ◽

Vol 27 (9) ◽

pp. 1875 ◽

Cited By ~ 242

Author(s):

Mohammed Baalousha ◽

Adriana Manciulea ◽

Susan Cumberland ◽

Kevin Kendall ◽

Jamie R. Lead

Keyword(s):

Organic Matter ◽

Iron Oxide ◽

Surface Properties ◽

Iron Oxide Nanoparticles ◽

Natural Organic Matter ◽

Oxide Nanoparticles ◽

Influence Of Ph

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Determination of the effects of tillage on the productivity of a sandy loam soil using soil productivity models

Research in Agricultural Engineering ◽

10.17221/46/2020-rae ◽

2021 ◽

Vol 67 (No. 3) ◽

pp. 108-115

Author(s):

Tanko Bako ◽

Ezekiel Ambo Mamai ◽

Istifanus Akila Bardey

Keyword(s):

Organic Matter ◽

Iron Oxide ◽

Bulk Density ◽

Aluminium Oxide ◽

Available Phosphorus ◽

Soil Productivity ◽

Water Capacity ◽

Available Water ◽

Available Water Capacity ◽

Tillage Methods

Based on the hypothesis that soil properties and productivity components should be affected by different tillage methods, field and laboratory experiments were conducted to study the effects of zero tillage (ZT), one pass of disc plough tillage (P), one pass of disc plough plus one pass of disc harrow tillage (PH) and one pass of disc plough plus two passes of disc harrow tillage (PHH) on the distribution of the bulk density, available water capacity, pH, organic matter, available phosphorus, iron oxide and aluminium oxide at different soil depths, and their effects on the soil productivity. The available water capacity, pH, organic matter and available phosphorus were found to increase with the degree of tillage, while the bulk density, iron oxide and aluminium oxide were found to decrease with the degree of tillage. The results show that the soil productivity index was significantly (P ≤ 0.05) affected by the tillage methods and found to increase with the degree of tillage.

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Self forming dynamic membrane filtration for drinking water treatment

Water Science & Technology Water Supply ◽

10.2166/ws.2021.329 ◽

2021 ◽

Author(s):

Suna Ozden Celik ◽

Nese Tufekci ◽

Ismail Koyuncu

Keyword(s):

Organic Matter ◽

Iron Oxide ◽

Natural Water ◽

Membrane Filtration ◽

Drinking Water Treatment ◽

Limit Values ◽

Remarkable Effect ◽

Alternative Treatment Option ◽

Dynamic Membranes ◽

Synthetic Water

Abstract Lab-scale continuous operation of self forming MF and UF dynamic membranes were investigated simultaneously by applying iron oxide as an alternative treatment option in those waters having natural organic matter (NOM), iron and manganese. Both dynamic membranes gave high removal rates and effluent concentrations of pollutants were below the limit values in synthetic water. 60–62% of DOC and 75–78% of UV254 were removed in low DOC synthetic water (LS) by MF and UF dynamic membranes, respectively. Although only 42–49% of DOC and 48–53% of UV254 could be removed by MF and UF dynamic membranes, remarkable effect on fouling alleviation was observed in high DOC synthetic water (HS). Iron oxide did not enhance the removal of organic matter in low DOC natural water (LN) as much as it did in synthetic water. Iron oxide led to the removal of high molecular weight organics, thus reversible fouling reduced almost 2 orders of magnitude through both types of dynamic membranes in high DOC natural water (HN). Reversible and ireversibe resistances were reduced by iron oxide to some extent in LN. Nevertheless the effect of iron oxide on fouling alleviation was much higher in HN than LN.

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Facilitated Heterogeneous Photodegradation of Dissolved Organic Matter by Particulate Iron

Environmental Chemistry ◽

10.1071/en04005 ◽

2004 ◽

Vol 1 (3) ◽

pp. 197 ◽

Cited By ~ 9

Author(s):

Julia A. Howitt ◽

Darren S. Baldwin ◽

Gavin N. Rees ◽

Barry T. Hart

Keyword(s):

Organic Matter ◽

Iron Oxide ◽

Dissolved Organic Matter ◽

Iron Oxides ◽

Aquatic Ecosystems ◽

Photochemical Reactions ◽

Freshwater Systems ◽

Particulate Iron ◽

Presence And Absence ◽

Australian Freshwater

Environmental Context. Iron oxides, as suspended minerals or as a colloidal phase, are common in Australian freshwater systems. Freshwater systems are also loaded with carbon-based substances, ‘dissolved organic matter’, but not all is biologically available as food to freshwater organisms. However, photochemical interactions between these iron oxides and dissolved organic matter provide a mechanism for biologically resistant carbon to re-enter the food web. Suspended iron oxides thus need to be considered in carbon cycles in aquatic ecosystems. Abstract. The photochemical degradation of dissolved organic matter (DOM) derived from the leaves of River Red Gum (Eucalyptus camaldulensis) was examined, with a particular focus on the photochemical generation of CO2, consumption of O2, and the effect of particulate iron minerals on these photochemical reactions. Solutions of leaf leachate were irradiated with ultraviolet and visible light in the presence and absence of amorphous iron oxides. Addition of fresh iron oxide was found to increase the rate of photodegradation of the organic matter by up to an order of magnitude compared to the reactions without added iron oxide. The ratio of CO2 produced to O2 consumed was ~1:1 in both the presence and absence of iron oxyhydroxide. The reactivity of the iron oxides was dependent on the preparation method and decreased with increased storage time. These results suggest that photochemical reactions on particle surfaces should be considered when examining carbon transformation in aquatic ecosystems, especially at sites with potential for the production of iron oxyhydroxides.

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