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Acid soil is an obstacle to agricultural development and a concern regarding food and environmental security. Therefore, a study was carried out for two consecutive years to see how lime and organic manure (OM) amendments affect yield and nutrient absorption in the Transplanted (T.) Aman–Mustard–Boro cropping pattern in an acidic terrace soil. With nine treatments and three replications, the experiment was set in a randomized complete block design. The treatments were applied to the first crop, T. Aman, with different dosages of lime (dololime at the rate of 1 and 2 t ha−1), OM (cow dung at 5 t ha−1, poultry manure at 3 t ha−1) and lime–OM combination, and their residual effects were studied in the following mustard and boro rice crops. Results demonstrate that the effect of lime and manure was more pronounced in the case of the second and third crops in the first year and of all crops in the pattern in the second year. In the first year, grain and straw yield of T. Aman as well as the overall system productivity were not influenced significantly by the application of lime and manure, but significant increases were obtained in the second year. As an average of both years, the highest grain yield of 5.2 t ha−1 (12% over control) was recorded for T. Aman, 1.7 t ha−1 (41% over control) for mustard and 5.9 t ha−1 (47% over control, 3.9 t ha−1) for boro rice when dololime was applied in combination with poultry manure. In both years, N, P, K and S uptake were significantly increased compared to the control in all the crops due to the combined application of lime and cow dung or poultry manure. Combined application of lime and manure amendment significantly improved nutrient availability and soil quality. Therefore, applying lime in combination with manure can be practiced to uplift crop productivity in acidic terrace soils.

Co-composting is an effective approach to biowaste management. The co-composting potential of banana pseudostem (BPS) and mushroom media waste (MMW) with chicken manure (CM) has not been explored, let alone their suitable ratios of co-composting being determined. Meanwhile, the imbalance ratios of the feedstocks used in the process severely restrict the physicochemical properties and quality of the finished product. For this reason, six different ratios of BPS, MMW, and CM, viz. 1:1:1, 1:2:1, 1:3:1, 2:1:1, 2:2:1, and 2:3:1, respectively (T1–T6), were composted together in aerobic conditions to identify the suitable ratio by evaluating the changes in the physicochemical properties in the composting process. According to the ratio of treatments, the feedstocks were mixed on fresh weight basis. The turning process of co-composting piles was repeated at seven-day intervals to maintain the uniform aeration throughout the composting period. The piles having BPS, MMW, and CM at ratios of 1:2:1, 1:3:1, and 2:3:1, respectively, demonstrated a longer thermophilic phase, indicating more complete decomposition and earlier maturity compared to piles with higher amount of BPS. Of the ratios, BPS:MMW:CM at 1:2:1 ratio (T2) resulted in the highest total nitrogen (1.53%), lowest C:N ratio (12.4), organic matter loss (54.5%), and increased CEC (41.3 cmol/kg). The highest germination index (129%) was also recorded in the T2 compost, indicating that it was toxic-free and safe for seed germination. The nutrient-rich compost with high alkaline pH (≥10) can effectively ameliorate soils of an acidic nature, for example, the acidity of Ultisols and Oxisols.

Ammonia volatilization from urea and ammonium containing compound fertilizers cause higher cost of fertilization in agriculture. In this study, an incubation experiment was carried out to compare the effect of different ratios of compound fertilizer amended with clinoptilolite zeolite on NH3 volatilization, soil exchangeable NH4 and available NO3 contents on Bekenu Series (Tipik Tualemkuts) with surface-applied urea without additives. Treatments with zeolite significantly reduced NH3 loss when compared with urea without addictives. They also improved retention of exchangeable NH4 and NO3 and this was possible because zeolite favoured formation of ammonium and nitrate over ammonia. There is a potential for compound fertilizer with zeolite to improve nitrogen efficiency by lowering ammonia volatilization and increasing accumulation of exchangeable NH4 and NO3. Key words: Ammonia volatilization, compound fertilizers, clinoptilolite zeolite, soil exchangeable ammonium, available nitrate.

Problem statement: Fertilizer N use efficiency is reduced by ammonia volatilization. Under low soil CEC and high pH, N from soil solution is released to the atmosphere. Ammonia loss due to low worldwide N use efficiency (33%) has been implicated in global warming. Thus, the objectives of this laboratory study were to evaluate the effectiveness of liquid humic and fulvic acids, isolated from tropical peat soils in reducing N loss from urea fertilizer as well as to investigate the ability of these acids to retain NH4 + and NO3 ¯ or reduce soil pH. Approach: Formulated liquid N fertilizers consisting of urea and different types of humic molecules (HA or FA or mixture of both), solid and liquid urea were surface applied to 250 g of soil. A closed dynamic air flow system was used to trap NH3 loss in boric acid after which samples were titrated with 0.01 M HCl to estimate NH3 loss. After 30 days of incubation, the soil was air dried and analysed for pH, exchangeable NH4 + , available NO3 ¯ and exchangeable cations. The results were analysed using SAS and treatments means were compared using Duncan's New Multiple Range Test (DNMRT). Results: The use of humic molecules reduced NH3 loss and increased exchangeable NH4 + . The high CEC of Humic Acids (HA) made the LHA treatment the best in reducing N loss after surface application. The presence of HA and Fulvic Acids (FA) increased NH4 + recovery. Even though, the soil pH of all the treatments were high, significant reduction of N loss was observed for humic molecules treatments. Conclusion: The use of liquid organic N fertilizer has the ability to reduce NH3 volatilization in acid soil. The use of both humic and fulvic acids could be effective in promoting NH4 + retention. Thus, it can be concluding that, humic substances, in general, have great ability in controlling NH3 loss and retaining NH4 + in acid

Ammonia volatilization is a direct loss of available nitrogen in agriculture. The objective of this study was to determine the effect of amending NPK fertilizer with different rates of clinoptilolite zeolite on ammonia volatilization, soil exchangeable ammonium, and available nitrate. Seven treatments evaluated were: 250 g soil alone (T1), 3.28 g ammonium nitrate (AN) without additive (T2), 44.6 g 5:3:2 formulated fertilizer + 31.77 g zeolite (T3), 44.6 g 5:5:5 formulated fertilizer + 26.36 g zeolite (T4), 37.17 g 6:6:6 formulated fertilizer + 18.92 g zeolite (T5), 22.30 g 10:10:10 formulated fertilizer + 4.06 g zeolite (T6), and 14.87 g 15:15:15 commercial fertilizer (T7). The ammonia loss was measured using close-dynamic air flow system method. Soil pH, exchangeable ammonium and available nitrate at the end of this study were determined using standard procedures. The mixture of formulated fertilizer and zeolite significantly reduced ammonia volatilization. Zeolite in the formulated compound fertilizers did not significantly affect soil exchangeable ammonium and available nitrate. Amending N, P, and K compound fertilizer could minimize ammonia loss. Keywords: Ammonium nitrate, zeolite, ammonia volatilization, soil exchangeable ammonium, soil available nitrate

Application of crude humin with urea and Egyptian rock phosphate (ERP) may reduce ammonia loss from urea. This study was conducted to determine the effect of mixing crude humin with urea and ERP on ammonia volatilization and selected soil chemical properties. Crude humin from four different composts was mixed with urea and ERP and ammonia loss from these treatments were evaluated using the closed-dynamic air flow system. Standard procedures were used to determine ammonia loss, soil pH, total nitrogen, exchangeable ammonium, available nitrate, exchangeable phosphorus, cations, organic matter, total organic carbon and cation exchange capacity. Amending urea with crude humin had no effect on total amount of ammonia loss. However, addition of the crude humin significantly increased pH, organic matter, total organic carbon, cation exchange capacity (CEC) and exchangeable cations of Bekenu series (Tipik Tualemkuts). Crude humin from selected waste compost can be used to improve soil chemical properties.

Excessive uses of fertilizer can create environmental problems such as soil pollution. This problem could be reduced by amending clinoptilolite zeolite with compound fertilizers. The objective of this study was to evaluate the effect of clinoptilolite zeolite rates in compound fertilizers (N: P: K) on maize nutrients uptake and use efficiency. The following treatments were considered and evaluated: soil alone (T1), 44.6 g 5:3:2 formulated fertilizer (12.83 g compound fertilizer + 31.77 g zeolite) (T2), 44.6 g 5:5:5 formulated fertilizer(18.24 g compound fertilizer + 26.36 g zeolite) (T3), 37.17 g 6:6:6 formulated fertilizer (18.25 g compound fertilizer + 18.92 g zeolite) (T4), 22.30 g 10:10:10 formulated fertilizer (18.24 g compound fertilizer + 4.06 g zeolite) (T5), and 14.87 g 15:15:15 commercial fertilizer (T6). Selected soil chemical properties, as well as, dry weight, nutrients concentrations, uptake and use efficiency were measured. Compound fertilizers with zeolite increased soil pH compared to soil alone (T1) and commercial fertilizer (T6). Application of compound fertilizer did no significantly affect total N and available nitrate in the soil. T6 gave better plant height and dry matter production among treatments. Nitrogen concentrations for all plant parts were similar for all treatments. T6 showed better P concentrations, uptake, and use efficiency. K concentrations in maize plant parts were significantly increased for treatments with zeolite except for roots. T5 and T6 significantly increased K uptake. T6 significantly increased N and P uptake and use efficiency, while T2 significantly increased K use efficiency. Amending N, P, and K fertilizers with higher dosage of clinoptilolite zeolite improved soil chemical properties, nutrient uptake of Masmadu variety. Compound fertilizers amended with clinoptilolite zeolite enhanced K use efficiency of Masmadu maize variety.

Adoption of new management techniques, such as clinoptilolite zeolite (CZ) utilization has attracted muchattention in the fertilizer industry. Accordingly, the aims of this study is to evaluate: if CZ, acting as an inertmaterial, when applied to the soil, might improve the selected soil properties, height, dry matter, nutrientconcentration, nutrient uptake, nutrient use efficiency on maize cultivation; the potential for (N:P:K) compoundfertilizer when incorporated with CZ to serve same standard as the commercial fertilizer in fertilizer industry.The effect of T1, T3 and T6 on soil total N was found to be significant, when compared with T7. Treatments withCZ on soil total P, K and available P, K differed significantly relatively to T1 and T7. The treatments T5 and T6had the highest accumulation of exchangeable NH4+ and available NO3- relatively to T1 and T7. The significanteffect of the treatments having CZ on N concentration, in uptake and use efficiency, suggests that CZincorporated with fertilizer can reduce NH3 loss, triggering the formation of NH4+ and NO3- over ammonia andincrease maize uptake. Relatively to P concentration, uptake and use efficiency, it was found that in mosttreatments having CZ, lower values were obtained, relatively to the commercial fertilizer, although T3 clearlyimproved P uptake in roots. Most of the treatments with CZ remained statistically similar in K concentration,uptake and use efficiency compared to commercial fertilizer. It may be concluded that treatments with higheramounts clinoptilolite zeolite ensured good retention of soil exchangeable cations, available P, and NO3- withinthe soil. Treatments with CZ improved N uptake and use efficiency in the maize crop tested.