Balanced nutrient elements in fertilizer play a critical role in oil palm seedling successful growth and development, and at the same time reduces of fertilizer losses in the environment. This study examines the effect of different levels of N, P 2 O 5 and K 2 O for oil palm seedlings in solution culture on growth traits, nutrient uptake in plant tissues and biomass accumulation under nursery conditions. Five concentration levels of N (50, 100, 300, 600 and 900 mg L ) were used in a completely randomized design (CRD) with five replications for each. Parameters measured during the growing period include -plant height, leaf number/plant, stem diameter, SPAD chlorophyll value, and at harvest -total leaf area, root dry weight, shoot dry weight and total dry weight. Different levels of N, P 2 O 5 and K 2 O showed significant effects on all the parameters studied. The highest values for diameter, plant height, leaf number/plant, total leaf area, root dry weight, shoot dry weight and total dry biomass were obtained using 100, 90 and 300 mg/L levels of N, P 2 O 5 and K 2 O, respectively. Most of the growth parameters, declined with lower levels of N, P 2 O 5 and K 2 O. The results of this study provide a new knowledge to produce oil palm plant with better nutrient management at the nursery under solution culture.

a b s t r a c tCharcoal production with higher heating value (HHV) requires high capital investment and high energy requirement for large scale production. In this study, charcoal production under self-sustained carbonization from oil palm biomass was proposed and tested at pilot scale, whereby temperature and exhaust gas flow rate were monitored but not controlled. This proposed system under self-sustained carbonization, whereby oil palm biomass is combusted to provide the heat for carbonization in inadequate oxygen is preferable to the industry due to its simplicity, ease of operation and low energy requirement. Moreover, the gaseous emissions are below the permitted level set by the environmental authorities. The considerable HHV obtained was between 23 and 25 MJ/kg with low gaseous emissions. The results obtained are acceptable and comparable to other studies on oil palm biomass conducted under controlled conditions with electrical heating elements.

The effectiveness of banana stem juice as a natural coagulant for treatment of spent coolant wastewater was investigated . Three main parameters were studied, namely, chemical oxygen demand (COD), suspended solids (SSs), and turbidity of effluent. Coagulation experiments using jar test were performed with a flocculation system where the effects of spent coolant wastewater pH as well as banana stem juice dosage on coagulation effectiveness were examined. The highest recorded COD, SS, and turbidity removal percentages by banana stem juice were 80.1%, 88.6%, and 98.5%, respectively, observed for effluent at pH 7 using 90 mL dosage. The inulin concentration in the banana stem was examined to be 1.22016 mg/mL. It could be concluded that banana stem juice showed tremendous potential as a natural coagulant for water treatment purposes and could be applied in the pretreatment stage of Malaysian spent coolant wastewater prior to secondary treatment.