Problem statement: Agriculture waste such as Sago Waste (SW) has a potential to cause pollution either on land or in water. In order to reduce this problem, a study was conducted to investigate the effect of three different treatments on the chemical characteristics of compost and humic acid from SW. Approach: The study had three treatments which were: T1: SW (80%) + chicken feed (5%) + chicken dung slurry (5%) + molasses (5%) + urea (5%), T2: SW (80%) + chicken feed (10%) + chicken dung slurry (5%) + molasses (5%) and T3: SW (80%) + chicken feed (10%) + chicken dung slurry (5%) + urea (5%). Composting was done for 60 days in a white polystyrene box with a size of 61.5×49×33.5 cm. The composts were analyzed for pH, total nitrogen, organic carbon, organic matter, ash, Cation Exchange Capacity (CEC), phosphorus and HA using standard procedures. Results: All treatments did not reach thermophilic phase. Compost of T2 had high quality (pH, total nitrogen, organic carbon, organic matter, ash, Cation Exchange Capacity (CEC), phosphorus and HA) compared to T1 and T3. The yield of HA of T2 was also significantly higher compared to those of T1 and T3. The compost characteristics of T1 and T3 were similar. The chemical characteristics of HA the 3 treatments were within the standard range reported by other researchers. Conclusion: T2 is more efficient in producing mature and good quality compost in 60 days compared to T1 and T3.

Agricultural waste, such as sago waste (SW), is one of the sources of pollution to streams and rivers in Sarawak, particularly those situated near sago processing plants. In addition, unbalanced and excessive use of chemical fertilizers can cause soil and water pollution. Humic substances can be used as organic fertilizers, which reduce pollution. The objectives of this study were to produce K- and ammonium-based organic fertilizer from composted SW and to determine the efficiency of the organic-based fertilizer produced. Humic substances were isolated using standard procedures. Liquid fertilizers were formulated except for T2 (NPK fertilizer), which was in solid form. There were six treatments with three replications. Organic fertilizers were applied to soil in pots on the 10th day after sowing (DAS), but on the 28th DAS, only plants of T2 were fertilized. The plant samples were harvested on the 57th DAS during the tassel stage. The dry matter of plant parts (leaves, stems, and roots) were determined and analyzed for N, P, and K using standard procedures. Soil of every treatment was also analyzed for exchangeable K, Ca, Mg, and Na, organic matter, organic carbon, available P, pH, total N, P, nitrate and ammonium contents using standard procedures. Treatments with humin (T5 and T6) showed remarkable results on dry matter production; N, P, and K contents; their uptake; as well as their use efficiency by maize. The inclusion of humin might have loosened the soil and increased the soil porosity, hence the better growth of the plants. Humin plus inorganic fertilizer provided additional nutrients for the plants. The addition of inorganic fertilizer into compost is a combination of quick and slow release sources, which supplies N throughout the crop growth period. Common fertilization by surface application of T2 without any additives (acidic and high CEC materials) causes N and K to be easily lost. High Ca in the soil may have reacted with phosphate from fertilizer to form Ca phosphate, an insoluble compound of phosphate that is generally not available to plants, especially roots. Mixing soil with humin produced from composted SW before application of fertilizers (T5 and T6) significantly increased maize dry matter production and nutrient use efficiency. Additionally, this practice does not only improve N, P, and K use efficiency, but it also helps to reduce the use of N-, P-, and K-based fertilizers by 50%.

The efficiency of urea is poor due to the substantial amount of N lost to the atmosphere by ammonia volatilization. Thus, the objectives of this greenhouse study were to evaluate the effectiveness of mixing urea with zeolite and sago waste water on N, P and K uptake and their use efficiency in maize cultivation, and soil exchangeable ammonium, available nitrate, pH, exchangeable K, and available P contents. The treatments evaluated were: No fertilizer (T0), 2.02 g urea (T1), 2.02 g urea + 30 g zeolite + 7 L sago waste water (T2), 2.02 g urea + 40 g zeolite + 7 L sago waste water (T3), and 2.02 g urea + 7 L sago waste water (T4). Triple Super Phosphate (TSP) and Muriate of Potash (MOP) were used as sources of P and K for all the treatments except for T0. These fertilizers were applied twice that is 10 and 28 days after planting. Phosphorus and K requirements of the test crop were met by applying TSP and MOP (standard rate for the test crop) to plants of all the treatments except T0. The mixtures of sago waste water, and zeolite, with urea had significant effect on dry matter, N, P, K uptake and N, P, K use efficiency compared with urea without additives. These mixtures also significantly increased soil exchangeable ammonium, K, Ca, Mg, available P, and nitrate contents compared with urea without additives. Amending urea with sago waste water and peat soil water can reduce ammonia loss by encouraging formation of ammonium and nitrate over ammonia. Additionally, the mixtures ensure N, P, K uptake and their use efficiency while at the same time making soil ammonium, K, Ca, Mg, P, and nitrate available for plant use.

Problem statement: Agriculture waste such as Sago Waste (SW) has a potential to cause pollution when the waste is discarded into rivers. In order to add value to SW, a study was conducted to produce potassium and calcium hydroxide, compost and Humic Acid (HA) from SW. Approach: The SW was air-dried and some grinded. The grinded SW was incinerated at 600°C. Potassium and calcium hydroxide was extracted by dissolving the ash in distilled water at a ratio of 1:500 (ash: water), equilibrated for 24 h at 150 rpm using a mechanical shaker and filtered. The ungrinded SW was used for compost production. The compost was produced by mixing SW (80%) + chicken feed (10%) + chicken dung slurry (5%) + molasses (5%). Results: The hydroxide extracted from ash of SW was used to isolate HA of composted SW. The molarity and pH of the hydroxide were 0.002M and 10 respectively. Calcium (42.88 mg kg −1) and potassium (29.51 mg kg −1) content were high in the hydroxide compared with other elements. The compost took about 60 days to mature. There was an increased in pH, ash, Cation Exchange Capacity (CEC) and HA and a decreased in temperature, C/N ratio, C/P ratio and organic matter. The hydroxide was able to extract 1% of HA from the composted SW. A comparison between the yields of HA extracted from the composted SW using the hydroxide of the SW and that of the analytical grade showed no statistically difference. The chemical characteristics of HA from the composted SW were in standard range. Conclusion: Potassium and calcium hydroxide, compost and HA can be produced from sago waste. Low morality of the hydroxide is able to produce good quality of HA from composted sago waste. The HA can be reconstituted with K and Ca from potassium and calcium hydroxide to produce K-Ca-humate and this needs to be investigated as a form of organic based fertilizer.