Adding Phosphate Fertilizer and Apple Waste to Pig Manure during Composting Mitigates Nitrogen Gas Emissions and Improves Compost Quality

Abstract

Calcium superphosphate and apple (Malus pumila Mill.) waste can be used for controlling N loss and improving compost quality during composting, whereas integrated addition of the two additives on composting process remains unexplored. Therefore, this study was conducted to investigate the effects of combined use of calcium superphosphate and apple waste on NH3 and N2O emissions and compost quality during pig manure and wheat (Triticum aestivum L.) straw composting. Mixtures of pig manure and wheat straw were combined with 6% phosphate fertilizer (PF), 15% apple waste (AW), 3% phosphate fertilizer + 7.5% apple waste (PA1), or 1.8% phosphate fertilizer + 10.5% apple waste (PA2) based on dry weight of the initial mixtures; a treatment with no additives served as a control (CK). The PF treatment took 3 d longer to reach thermophilic phase than the CK, PA1, and PA2 treatments. The treatments of PF and PA1 reduced NH3 and N2O emissions by 67 and 45%, respectively. Moreover, N loss in PF and PA1 treatments (31.8 and 30.1%, respectively) was significantly less than in the CK. A pot experiment showed that application of the compost with PA1 treatment could increase plant height and dried biomass of Chinese pakchoi (Brassica campestris L. ssp.). We recommend adding 3% phosphate fertilizer and 7.5% apple waste to pig manure during composting. Core Ideas Effect of phosphate fertilizer (PF) and apple waste (AW) on N conversion was studied. Combination of 3% PF and 7.5% AW is more beneficial for composting. Using 3% PF and 7.5% AW reduced NH3 and N2O by 67% and 40% during composting. The compost of 3% PF and 7.5% AW improved plant height and dried biomass.

Molecular Speciation of Phosphorus in Soil Under Various Long-Term Fertilization Regimes

“…Our results are also consistent with the ndings of Cadot (2018) who reported that fertilization can signi cantly increase the number of results per corn plant and the weight of stems and leaves (Table 2). In the current study, higher plant height and thicker stem diameter were found after the manure fertilizer treatments (MN, MNP), but there was no signi cant difference between the unfertilized and mineral fertilizer (NF, NP) soils, which is inconsistent with previous research suggesting that fertilizer application increases the height and stem of plants (Jiang et al, 2019). The higher nutrient content in soil caused by the application of manure, and a signi cant reduction in the soil pH after application of mineral fertilizer (Table 1; Kmet'ova and Kovacik, 2013).…”