Combination of Inorganic Nitrogen and Organic Soil Amendment Improves Nitrogen Use Efficiency While Reducing Nitrogen Runoff

Abstract

Improved nitrogen fertiliser management and increased nitrogen use efficiency (NUE) can be achieved by synchronising nitrogen (N) availability with plant uptake requirements. Organic materials in conjunction with inorganic fertilisers provide a strategy for supplying plant-available N over the growing season and reducing N loss. This study investigated whether a combined application of inorganic N with an organic soil amendment could improve nitrogen use efficiency by reducing N loss in runoff. Nitrogen runoff from a ryegrass (Lolium multiflorum) cover was investigated using a rainfall simulator. Nitrogen was applied at low, medium and high (50, 75 and 100 kg/ha) rates as either (NH4)2SO4 or in combination with a poultry manure-based organic material. We showed that the NUE in the combination (58–75%) was two-fold greater than in (NH4)2SO4 (24–42%). Furthermore, this combination also resulted in a two-fold lower N runoff compared with the inorganic fertiliser alone. This effect was attributed to the slower rate of N release from the organic amendment relative to the inorganic fertiliser. Here, we demonstrated that the combined use of inorganic and organic N substrates can reduce nutrient losses in surface runoff due to a better synchronisation of N availability with plant uptake requirements.

Exploring the potential of enhanced organic formulations for boosting crop productivity, nutrient utilization efficiency, and profitability in baby corn-kabuli gram-vegetable cowpea cropping system

“…The higher agronomic efficiency could be attributed to the fact that organic manure alters soil quality following its application, influencing factors such as organic matter content, soil structure, and biological activity (Tisdall and Oades, 1982;Bronick and Lal, 2005). Phillips et al (2022) reported that addition of organic material in conjuction with inorganic fertilizers increase the nitrogen use efficiency two fold by reducing runoff loses, slow release of nutrients with better synchronization with plant nutrient uptake in rye grass. Organic amendments such as humified sledge and poultry manure signifcnatly affected the N uptake and improves the nitrogen use efficiency in rice crop (Ofori et al, 2005).…”

Nitrogen fertilization value of compost and dried dung in soils with contrasting synthetic nitrogen fertilization histories

“…OAs encompass a wide range of products, including animal manures, biosolids, green manure and crop residues, manufacturing wastes, and composts (Goss et al, 2013; Quilty & Cattle, 2011). A major benefit of using OAs as a partial or complete substitute for synthetic N fertilizers is their potential to reduce environmental N losses (Phillips et al, 2022; Wei et al, 2021; Xia et al, 2017), owing to the typically slower supply of inorganic (mineral) N (IN) for plant uptake that is often claimed to be more synchronized with plant demands. Indeed, synchronizing the temporal supply of N with plant demands is key to maximizing the value of N inputs and minimizing environmental N losses (Crews & Peoples, 2005).…”