SW—Soil and Water: Lignin-based Interpolymer Complexes as a Novel Adhesive for Protection against Erosion of Sandy Soil

Abstract

New amino-containing soil conditioners based on lignosulphonate (LS), a by-product of the papermaking industry, have been developed to create an artificial soil macrostructure and to reinforce surface layers, withstanding wind and water erosion on light sandy soil.The conditioners created are interpolymer complexes (IPCs) formed by an intermolecular reaction between LS and polymer or oligomer amines in aqueous medium. Owing to a pronounced gluing ability, IPCs are capable of reinforcing the surface layers of sandy soil with a thickness of 1·2–10·2 mm and a penetration resistance of 0·16–0·98 MPa at application rates of 0·045–0·320 kg m−2in terms of dry matter content. It has been established that the surface layers formed by applying an IPC containing oligomer amine are characterized by worse mechanical properties and stability against erosion in comparison to those formed with the IPC containing polymer amine. The introduction of polyvalent metal salts, such as FeCl3and Cu(NO3)2, into the IPC results in the formation of triple polymer–metal complexes, whose structuring and stabilizing action on sandy soil is more pronounced than for double IPCs. This reveals itself in a decrease in soil losses by 20–25% at a wind speed of 25 m s−1, a drop in soil losses of 30–35% and a reduction in the water surface runoff by 40–45% under the simulation of water erosion conditions.The layers formed by the application of both double and triple IPCs are photoresistant owing to the peculiarities of the chemical structure and composition of these glues.Clover seeds easily germinate through the air-dry-reinforced surface layers formed at an application rate of no more than 338 kg m−2in terms of dry matter content.