Che Fauziah Ishak

Characterization and Feasibility Assessment of Recycled Paper Mill Sludges for Land Application in Relation to the Environment

The disposal of industrial paper mill sludge waste is a big issue and has a great importance all over the world. A study was conducted to determine the chemical properties of recycled paper mill sludge (RPMS) and assess its possibilities for land application. RPMS samples were collected from six different paper mills in Malaysia and analyzed for physical and chemical properties, heavy metals, polycyclic aromatic hydrocarbons, 13C-NMR spectra and for the presence of dioxins/furans. The RPMS was dewatered, sticky with a strong odour, an average moisture of 65.08%, pH 7.09, cation exchange capacity (CEC) 14.43 cmol (+) kg–1, N 1.45, P 0.18, K 0.12, Ca 0.82, Mg 0.73, Na 0.76 and Al, 1.38%. The polycyclic aromatic hydrocarbons (PAHs) and heavy metals levels were below the standard Class 2 limits. The dioxin and furan were in below the standard concentration of Class 1. The most prominent peak in the 13C-NMR spectra of RPMS was centered at 31 ppm, proving the presence of methylene (-CH2) groups in long aliphatic chains, with lipids and proteins. The signal at 89 ppm and highly shielded shoulder at 83 ppm were due to presence of cellulose carbon C-4, and the peak at 63 and 65 ppm was due to the cellulose carbon spectrum. The RPMS therefore contains significant amount of nutrients with safe levels of heavy metals and PAHs for environment and can be used as a fertilizer and soil amendment for land application.

15N-labelled fertiliser recovery by maize (Zea mays L.) and leaching of nutrients as influenced by oil palm empty fruit bunch biochar in a mini-lysimeter under controlled tropical environment

ABSTRACT Converting oil palm empty fruit bunches into biochar is an alternative waste management method and has strong potential to improve N fertiliser use efficiency in agriculture. The aim of this study was to determine the effectiveness of oil palm empty fruit bunch biochar (EFBB) in improving recovery of 15N-labelled nitrogen fertiliser by maize (Zea mays L.) and leaching of mineral N and K. An experiment was conducted in a mini-lysimeter system with randomised complete block design layout and six replications under controlled environment in a rain shelter. Each mini-lysimeter was filled with 20 kg of sandy loam soil before adding EFBB (0, 5, 10 and 20 Mg ha−1). The N source used was (15NH4)2SO4 at 80 kg N ha−1 (2 at% 15N excess). Maize was irrigated to induce leaching every 4 days. Maize plant and soils were sampled 58 days after sowing (tasselling stage). Application of EFBB significantly reduced cumulative leachate volume and mineral N leaching. Soils applied with EFBB significantly improved 15N fertiliser recovery in maize and dry matter weight. This study shows that EFBB has the potential to be applied on highly weathered acidic soil as an amendment to improve fertiliser efficiency and crop growth.

Biochar-compost mixture as amendment for improvement of polybag-growing media and oil palm seedlings at main nursery stage

PurposeProduction of oil palm seedling in the nursery mainly utilises top soil as polybag medium. These soils, especially in tropical regions, are acidic and have low organic matter content. The aim of this study was to investigate the effects of oil palm empty fruit bunch (EFB) biochar and compost incorporation as amendment in polybag medium for oil palm seedlings growth at the nursery stage.MethodsA polybag experiment was conducted with four biochar rates (0, 0.5, 1.0 and 1.5% w/w C addition), two compost rates (0 and 30% v/v), and two fertiliser application rates (75 and 100% of recommended rate). The effects of biochar, compost, and biochar-compost combination on oil palm seedling growth was evaluated and the effectiveness of EFB biochar in retaining soil nutrients was determined indirectly by measuring amount of nutrient leached through the polybag medium.ResultsBiochar, compost, and biochar-compost amendment improved polybag media’s chemical properties (pH, total C and N, C:N ratio, CEC, Mg, and Ca). There were no significant effects of the amendments on shoot biomass. However, root growth and shoot:root ratio significantly improved with 1.5% w/w C addition and 30% (v/v) compost with 75% recommended fertiliser rates applied. Furthermore, nutrient leaching measurement indicates that, EFB biochar significantly reduced ammonium-N leaching up to 21–46%.ConclusionsOverall, this study demonstrates the potential of biochar and compost co-application to improve the chemical properties of polybag medium and root development of oil palm seedlings.

Application of raw and composted Recycled Paper Mill Sludge on the growth of Khaya senegalensis and their effects on soil nutrients and heavy metals.

The paper industry performs an essential role in the global economy of the world. A study was conducted on the paper mill sludge that is applied on the Khaya senegalensis for 4 crop cycle for 1 year growth at glasshouse, Faculty of Agriculture, Universiti Putra Malaysia. Paper Mill Sludge (PMS) and composted Recycled Paper Mill Sludge (RPMS) was used with nitrogen (0, 150, 300 and 600 kg ha-1) at the ratio of 1:1 (Recycled Paper Mill Sludge (RPMS): Empty Fruit Bunch (EFB). The growth parameters were measured twice a month for 6 months. Plant nutrients and heavy metal uptake were determined. The paper mill sludge has the potential to be a supplementary N fertilizer as well as a soil amendment. The application of RPMS with N, significantly contributed to the improvement in plant growth parameters such as plant height (193 cm), basal diameter (27.00 mm), total plant biomass and improved soil physical and chemical properties. Total concentrations of heavy metals in soils were below the critical values. Hence, the paper mill sludge can be successfully used as soil amendment in acidic soil without any serious threat. The use of paper mill sludge for soil fertility, shows improvement in land application and signifies a unique opportunity to recycle sludge back to the land to alleviate the potential waste management problem.

Laboratory Evaluation on Ammonia Volatilization from Coated Urea Fertilizers

ABSTRACT Coated urea fertilizers are assumed to enhance crop yield and reducing the environmental pollution. Nevertheless, many of the coated urea fertilizers are expensive, thus not readily available for most farmers. In addition, many of these fertilizers release N not in tandem with the plant’s need, thus retard growth. Therefore, a laboratory study was conducted to evaluate effects of coated urea fertilizers on N losses via volatilization. Measurement of ammonia volatilization was carried out using the closed-dynamic air flow system. The study for ammonia volatilization was conducted using different rates of fertilizer (50, 100, and 200 kg N ha−1) with different types of fertilizer (Urea, Sulfur-coated urea; SCU and Gypsum sulfur coated urea using rotating drum; GSCUD) in 37 days of incubation. The results indicate that SCU represents the best fertilizer which decreases the amount of ammonia volatilization at each rate of fertilizer. Besides, the rate of 50 kg N ha−1 has the lowest percentage of ammonia volatilization. Moreover, the result proved the effectiveness of coating urea fertilizer may reduce the ammonia loss to the environment and new product which GSCUD can be comparable to the commercial product.

In-situ immobilization of lead using different source of phosphate amendments for the organic production of misai kucing (Orthosiphon stamineus)

Sustainable organic herbal production requires utilization of bio-waste materials as plant nutrient sources due to its economical aspect and would ensure continuous productivity. The usage of organic wastes in organic farming system (OFS) as fertilizers and soil amendments should be monitored as the accumulation of heavy metals has been reported in several studies. Glasshouse study has been conducted to assess the effectiveness of Pb immobilization due to chicken manure application using different sources of phosphate materials; bone meal (BM), Egyptian rock phosphate (ERP) and triple super phosphate (TSP). From the fractionation of glasshouse study, the percentage of exchangeable fraction of Pb was reduced with application of P-amendments with the highest of 20.2% of reduction recorded for 2 t/ha application of TSP. This is followed by reduction in exchangeable fraction for others treatments: 2 t/ha of BM (4.1%), 4 t/ha of BM (5.1%), 1 t/ha of ERP (8.1%) and 2 t/ha of ERP at 17.6%. These treatments were recorded as being able to stabilize the Pb as indicated in the percentage reduction of phyto available pools into a more stable form of residual pool.

Soil Properties (Physical, Chemical, Biological, Mechanical)

Introduction ............................................................................................................ 104 Physical Properties of Malaysian Soils .................................................................. 105 Soil Physical Properties..................................................................................... 105 Chemical Properties of Malaysian Soil .................................................................. 112 Cation Exchange Capacity ................................................................................ 112 Soil Acidity........................................................................................................ 113 Processes of Acid Generation in Soils ................................................................... 113 Natural Ecosystems ................................................................................................ 113 Highly Weathered Soils ..................................................................................... 113 Acid Sulfate Soils .............................................................................................. 114 Peatland ............................................................................................................. 115 Ways to Overcome Soil Acidity ............................................................................. 117 Soil Organisms, Their Beneficial Activities, Habitat, and Diversity in the Soils of Malaysia .................................................................................................... 118 Introduction ....................................................................................................... 118 Soil Organisms ....................................................................................................... 118 Macroorganisms ................................................................................................ 119 Functions of the Macroorganisms ................................................................ 121 Soil Microorganisms ......................................................................................... 126 Functions and Beneficial Characters of the Soil Microorganisms ......................... 127 Releasing Nutrients from Organic Matter ......................................................... 127 Fixing Atmospheric Nitrogen ............................................................................ 127 Legumes ....................................................................................................... 127 Symbiotic Nitrogen Fixation ........................................................................ 128 Nonsymbiotic Nitrogen Fixation .................................................................. 128 Diazotrophs Associations in Rice ................................................................. 128 Increasing Phosphorus Availability ................................................................... 129 Phosphate-Solubilizing Bacteria .................................................................. 129