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To estimate the order of importance of factors affecting the stability and maturation of compost, cow feces and maize stalks were co-composted at different aeration rates "AR" (22, 44 and 66 L kg -1 DM . min -1 ) of C/N ratios (16, 19, 22), and moisture contents "MC" (60 %, 65 %, 70 %). A composting process was monitored by physical and chemical methods. The thermophilic phase with all treatments was long enough to meet sanitation requirements. The emitted carbon dioxide and the losses total organic carbon and total extractable carbon increased with increasing aeration rate, there was a significant difference between the treatments with low and high aeration rate, but no significant differences between those two treatments and the moderate aeration rate. The total nitrogen contents of all treatments decreased during the thermophilic phase, while it was increased after that for all treatments except T8. The compost with the highest initial C/N ratio was significantly different from the other treatments and had the highest values of humic substances, degree of humification and humification rate. The compost with the lowest initial C/N ratio was significantly different from the other treatments and had the lowest germination index (57-67%). Aeration rate was the main factor influencing compost stability, while the C/N ratio mainly contributed to compost maturity, and the moisture content had an insignificant effect on the compost quality. The recommended parameters for composting are an aeration rate of 0.44 L kg -1 DM. min -1 and a carbon to nitrogen ratio of 19 with moisture content of 60-70%.

T HIS study aims to clarify the individual and combined effect of both subsoiling tillage and compost on chemical properties of saline soil and its productivity. A field experiment was conducted during winter season of 2018/2019 at El-Hamoul area, Kafr El-Sheikh Governorate, Egypt. This experiment included 6 treatments with three replicates (18 plots) where the main factor wastillage (subsoiling tillage, ST; non-subsoiling tillage, NT) and thecompost (sulphur compost, SC; non-sulphur compost, NSC) applied at 24.0 Mgha-1 represented the second factor. All plots were sowed by wheat plant. After harvesting, straw and grains were weighted and soil samples of each plot were taken at depths of 0-15, 15-30, 30-45, 45-60 and 60-90 cm to determinate some chemical properties (pH, EC, ESP and OM) and the available macronutrients (N, P, K and S) in soil. Compost application without and with subsoiling tillage significantly decreased the soil pH, ESP, EC and increased OM and soil available macronutrients (N, P, K and S). Subsoiling tillage resulted in a significant decrease of soil ESP, EC, OM and the soil available N, P, K and S, while there was slightly increasing in soil pH. Application of compost either without or with ST significantly increased both straw and grains yields of wheat plant compared with control. Treated saline soil with compost and ST had a high positive impact on soil chemical properties and its productivity of wheat plant, where the preference was for ST and SC treatments.

to evaluate the efficiency of amending a calcareous soil with two type of sulphur compost for improving soil properties and its content of available macro-and micro-nutrients and growth of barley plants. Two types of sulphur compost were produced, the first one from adding S to compost during composting (DS) process and the other from mixing S with non-sulfurized compost after composting (AS). The additional S rates for both two types of compost were 1.0, 2.0 and 3.0 %. Before planting, each one of sulphur compost was applied at rates of 0.0, 10.0 and 20.0g kg-1 and mixed well with the soil. After 70 days of planting the plants were harvested. Dry matter yield of the harvested and its content of nutrients were determined. Also, a soil sample was taken and analyzed for some chemical properties and its content of available nutrients.The data showed that, compared to the control, both two types of applied sulphur compost had a positive effect on the studied soil properties and the growth parameters of cultivated plants. A decrease in calcareous soil pH, EC and the content of CaCO 3 was observed, however an increase in soil CEC, OM and available macroand micronutrients as a result of sulphur compost applications was induced. Sulphur compost applications were associated by an increase in plant dry matter yield and its content of macroand micronutrients. So, the ameliorative influence of sulphur compost especially that carried out during the composting period on chemical properties and productivity of calcareous soil clearly occurred.

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