A biochar and Fulvic Acid Usage-Based Approach to Reduce Pollution Resulting from the use of Mineral Fertilizers

Abstract

Abstract Nowadays, due to pollution in world due to due to excessive consumption of mineral fertilizers, the limiting or minimizing their use has become a major strategy for environmentalists. The research work objective was to reduce quantities of mineral fertilizers, especially NPK fertilizers, by gradually replacing nitrogen fertilizers with fulvic acid and biochar. Four different combinations of mineral fertilizers were used as soil application (NPK1: 120, 160 and 143, NPK2: 180, 310 and 190, NPK3: 240, 475 and 240 and NPK4: 300, 635 and 285 kg ha-1), biochar as soil application (B0: without biochar, B1: 15 and B2: 30 Mg ha-1) and fulvic acid as foliar addition (FA0: without fulvic acid and FA1: 0.2, gL-1) were studied using pot experiment during 2017/2018 season using wheat plants. The results indicated general increment trend in almost investigated parameters with increasing fertilizers level especially that combined with biochar at any rate and fulvic acid. The highest soil N and P contents (63.59 and 38.35 mgkg-1) were reported with NPK4 + B2 + F1 while the lowest values (31.09 and 2.96 mgkg-1) were recorded under the lowest fertilization level without application of B or FA. Unlike, maximum K contents (216.79 and 214.88 mgkg-1) were reported under adding the NPK4 or with B2 without FA. The grain yield recorded maximum values (5 Mg ha-1) under combined application of maximum NPK fertilizer level, 30 Mg ha-1 of biochar and fulvic acid while applying the minimum NPK fertilization level (level 1) without any applications of biochar or fulvic acid resulted in the lowest values (2.94 Mg ha-1). The results showed that it is possible to partially reduce the quantities of mineral fertilizers used and replace them with a complementary addition from fulvic acid and biochar, and this is reflected in the reduction of environmental pollution resulting from the use of mineral fertilizers. Also, the combination of NPK and biochar led to an improvement in the productivity of wheat grown in sandy lands, as it reduced the loss of nutrients, and the addition of fulvic acid led to an increase in plant resistance to stress conditions that appear under sandy soil conditions.