Use of a layered double hydroxide (LDH) to buffer nitrate in soil: long-term nitrate exchange properties under cropping and fallow conditions

Abstract

The potential use of a layered double hydroxide (LDH) to act as a nitrate buffer system in soil in order to reduce the movement of nitrate was investigated. Long-term plant and soil experiments were carried out under greenhouse conditions with the following objectives: (i) evaluate the nitrate adsorption capacity of the LDH during crop growth, and its influence on N uptake, (ii) study the ability of the LDH to adsorb nitrate mineralized during fallow periods, and its influence on nitrate leaching, (iii) evaluate the reversibility for nitrate exchange of the LDH under cultivation conditions, and (iv) determine the nitrate buffer capacity of the soil after LDH application. The LDH adsorbed nitrate from the soil solution during the growth period without affecting plant N uptake. As a result of the adsorption of nitrate on the LDH, the nitrate-N concentration in the soil solution at harvest was reduced by a factor of ten compared to a soil without LDH. The LDH efficiently adsorbed nitrate that was mineralized in the soil during periods without cultivation, reduced nitrate-N leaching losses by about 80%, and kept this nitrate available for a following crop. The nitrate buffer capacity of the soil after 15months increased from 0.3 (without LDH) to 2.7 with the application of 10g LDH kg −1 soil. It is concluded that the LDH has a potential to be used as a long-term nitrate exchanger to control the movement of nitrate in soil, and thereby reduce risks of nitrate leaching in crop production in sensible areas.

Mineral-Based Slow Release Fertilizers: A Review

“…(Komarneni et al, 1996;De Roy et al, 2001;Khan and O'Hare, 2002) even at room temperature. Since LDH has positive charges on a layer surface and thus could be used as a nitrate carrier or for controlled nitrate release for agricultural uses, several studies have been conducted for nitrate ion release characteristics to check the feasibility of LDH as the slow release fertilizer (Komarneni et al, 2003;Gillman and Noble, 2005;Halajnia et al, 2013;Urena-Amate et al, 2011;Torres-Dorante et al, 2009). Komarneni et al (2003) carried out the experiment of nitrate release from several LDHs in simulated soil solutions and investigated the influences of the type of anions present in the soil solution, their concentration, and crystal size and charge density of LDHs.…”

Niche construction by the invasive Asian knotweeds (species complex Fallopia): impact on activity, abundance and community structure of denitrifiers and nitrifiers

“…Samples were stored at -18°C prior to analysis. There is no problem of nitrite or nitrate sorption on soil particles since the anionic exchange capacity (AEC) is mainly developed in acidic tropical and sub-tropical soils with a high content of aluminium and iron hydroxides/oxides or in some volcanic ashes derived soils (Torres-Dorante et al 2009). These soils represent only 1% of the total soil surface of the globe (TorresDorante et al 2009).…”

Anion Selectivity of Layered Double Hydroxides: Effects of Crystallinity and Charge Density

“…Actually, some studies have reported the potential use of LDHs as adsorbents or reservoirs of nitrate. [9,10,[13][14][15][16][17][18] However, the selectivity of LDHs for nitrate is generally considered not to be high, and a large number of studies have reported that anions with a higher charge density tend to be more preferentially intercalated into LDHs. [6][7][8]19,20] According to a report by Miyata, [19] the order of exchange selectivity for monovalent anions in the case of Mg-Al LDHs (Mg/ Al = 2.3) is OH -> F -> Cl -> Br -> NO 3 -> I -, and according to a report by Costa et al, [20] the order of exchange selectivity based on a computational simulation with Zn-Al LDHs (Zn/Al = 2) is CO 3 2-> OH -> F -> Cl -> Br -> NO 3 -.…”