In Malaysia, four soil conservation practices are oft en recommended for non-terraced oil palm (E... more In Malaysia, four soil conservation practices are oft en recommended for non-terraced oil palm (Elaeis guineensis Jacq.) plantations. Th ese practices are oil palm empty fruit bunches (EFB), Ecomat (a compressed EFB mat; ECO), and pruned oil palm fronds. Th ese three oil palm residues are used as organic mulching materials. Th e fourth method is silt pits (SIL) which are soil trenches to collect nutrients from runoff water and later redistribute them back into the soil. Nonetheless, the relative eff ectiveness of these four methods in improving soil and oil palm properties have never been studied. A 3-yr fi eld experiment was consequently conducted to determine their relative eff ects on increasing soil chemical properties (pH, cation exchange capacity, organic C, total N, available P, and exchangeable K, Ca, and Mg) and oil palm nutrition levels (N, P, K, Ca, and Mg). Biomass decomposition rate and nutrients release rate in the fi eld by the three mulching materials were also determined. Results showed that EFB mulching was signifi cantly better than the other three soil conservation practices in improving nearly all of the measured soil and plant parameters. Empty fruit bunches was most eff ective partly because of the combined eff ects of higher amounts of dry matter added and the higher nutrient concentrations in the EFB than in other mulching materials. Silt pitting was found not to be as eff ective as EFB because SIL could only trap and return nutrients back into the soil, whereas EFB could do both: trap nutrients and release additional nutrients into the soil as it decomposes.
The main objectives of this study were to determine the physical changes in oil palm empty fruit ... more The main objectives of this study were to determine the physical changes in oil palm empty fruit bunches (EFB) and EFB mat (Ecomat), which were used as soil mulching materials, during their decomposition in the field, as well as to compare the soil water content under these mulches and with bare soil. A field experiment was conducted at an estate using ten-year-old oil palm trees. Experimental design was a Randomized Complete Block with two treatments (EFB and Ecomat) and three replications. EFB was applied at 1000 kg palm-1 as a single layer on the soil surface. Ecomat was applied as a single layer with an area of 4 m2. Physical properties of EFB and Ecomat, measured every two month for six months, were bulk density, water content, water retention, and saturated hydraulic conductivity. Soil water content up to 750 mm depth was further measured on a daily basis. Results showed that EFB was better than Ecomat as a mulching material to conserve soil water. As compared to Ecomat, EFB had a lower bulk density (two times less dense), higher saturated hydraulic conductivity (about two times higher) and higher water content (between 20 to 57% more water). EFB was also found to hold its water more strongly than Ecomat. On average, the soil under EFB mulches had, nearly 27% more water than the soil under Ecomat mulches, and 38% more than bare soil. The soil under Ecomat mulches had only 8% more water than bare soil on average. Based on the model simulations, 5 layers of Ecomat would conserve as much soil water as 1 layer of EFB. Both mulching materials were estimated to fully decompose in the field in about 9 months.
The hydrological condition and its related moisture characteristics of the soil are important fac... more The hydrological condition and its related moisture characteristics of the soil are important factors contributing to forest and plant growth in peatland ecosystem. These hydrological characteristics would also provide an indirect view point of the current management practices in the case of land cover other than natural forest. This paper reports our recent research findings on the behavior of field hydraulic conductivity (K) and moisture characteristics of peatlands typically found in Sarawak. The field hydraulic conductivity measurements were carried out on different forest types, namely mixed peat swamp, Alan forest and Padang Alan forest in the virgin peat swamp forest at Loagan Bunut National Park using auger hole and pumping method.. The moisture characteristics of peat materials were obtained from samples taken from different areas in Sarawak representing different degrees of peat decomposition under various agronomic practices. The moisture characteristic determination was conducted in the laboratory using a combination of sand/kaolin box for suction pressure less than 500 cm (pF<2.7; < 0.5 bar) and pressure membrane apparatus for 500-15000 cm (pF 2.7-4.2 or 0.5-15 bar).
Boron (B) deficiency is a frequent issue in the oil palm plantation. The symptoms can be observed... more Boron (B) deficiency is a frequent issue in the oil palm plantation. The symptoms can be observed in the leaf malformations namely hook leaf , crinkle leaf , transient leaf, , fish bone leaf and stump leaf form. These symptoms of leaf malformation are due to leaf lamina development interference which leads to reduction of photosynthetic activity. As B deficiency increases, leaf area and yields slowly decreases and in severe cases no fruit is produced. The common belief that B is not an important nutrient in the early growth stage of oil palm is actually a misconception. Theoretically, continuous supply of B is necessary to prevent the occurrence of deficiency symptoms at an early growth stage of oil palm. Due to its essentially to the crop and the lack of attention given to this micro nutrient this research has been initiated to establish a relationship between B and N fertilization. It is hoped that the outcome of this research will lead to new approaches on effective B management ...
The hydrological condition and its related moisture characteristics of the soil are important fac... more The hydrological condition and its related moisture characteristics of the soil are important factors contributing to forest and plant growth in peatland ecosystem. These hydrological characteristics would also provide an indirect view point of the current management practices in the case of land cover other than natural forest. This paper reports our recent research findings on the behavior of field hydraulic conductivity (K) and moisture characteristics of peatlands typically found in Sarawak. The field hydraulic conductivity measurements were carried out on different forest types, namely mixed peat swamp, Alan forest and Padang Alan forest in the virgin peat swamp forest at Loagan Bunut National Park using auger hole and pumping method.. The moisture characteristics of peat materials were obtained from samples taken from different areas in Sarawak representing different degrees of peat decomposition under various agronomic practices. The moisture characteristic determination was conducted in the laboratory using a combination of sand/kaolin box for suction pressure less than 500 cm (pF<2.7; < 0.5 bar) and pressure membrane apparatus for 500-15000 cm (pF 2.7-4.2 or 0.5-15 bar).
INTRODUCTION Malaysia and Indonesia are the two largest producers of palm oil in the world. In Ma... more INTRODUCTION Malaysia and Indonesia are the two largest producers of palm oil in the world. In Malaysia, oil palm occupies over four million hectares, occupying about 12% of Malaysia's land area. One of the by-products of the palm oil milling process is the empty fruit ...
Problem statement: The oil palms are mainly grown in the humid tropics with high rainfall. Solubl... more Problem statement: The oil palms are mainly grown in the humid tropics with high rainfall. Soluble Nitrogen (N) and Potassium (K) fertilizers are commonly required by the oil palm plantations to maximize palm productivity due to the highly weathered soils with low fertility. Thus, leaching losses of N and K nutrients may be unavoidable and these nutrients may move further downward and eventually cause groundwater pollution. This study reports the leaching of N and K nutrients in a mature oil palm field as affected by fertilizer rates and soil depths and its effect on groundwater quality during the monsoon period in Tawau, Sabah. Approach: The sources of N and K fertilizer were Ammonium Chloride (AC) and Muriate of Potash (MOP), respectively. Soil water samplers were installed at depths of 30, 60 and 120 cm in four fertilizer treatments, namely, N0P0K0 (Control plot, no N and K), N0P2K1 (K1 = 4.5 kg MOP palm −1 year −1 ), N1P2K1 (N1 = 3.75 AC kg palm −1 year −1 ) and N1P2K0. Three replications were used in the experiment. Monitoring wells were installed in the above treatment plots and in another treatment, N2P2K1 (N2 = 7.5 kg AC palm −1 year −1 ) to investigate the effect of excessive N rate on groundwater quality. Samplings were done at 15 day intervals for a duration of 150 days from . Results: The mean NH 4 -N concentration of N1P2K1 at 33.69 mg L −1 was significantly higher than N1P2K0 at 8.15 mg L −1 . In the presence of K, NH 4 -N concentrations increased 4.1 fold when N fertilizer was applied and 3.5 times in the absence of N application. The mean NH 4 -N concentration was 17.89 mg L −1 at 30 cm depth declining to 12.19 and 6.52 mg L −1 at soil depths of 60 and 120 cm, respectively. The transformation of NH 4 -N to NO 3 -N was not a major process during the monsoon period. The leaching losses of inorganic N were 1.0 and 1.6% of the applied fertilizer for N1P2K0 and N1P2K1 respectively. For K, the leaching losses were 5.3 and 2.4% for N0P2K1 and N1P2K1 respectively. The concentrations of NH 4 -N, NO 3 -N and K in groundwater ranged from 0.23-2.7, 0.07-0.25 and 0.63-9.54 mg L −1 , respectively. Conclusion/Recommendations: N and K concentrations in the soil solution decreased with soil depth and their leaching losses were related to rainfall pattern, fertilizer treatment and nutrient uptake by roots. Groundwater quality was not affected by the applications of N and K fertilizers at the optimum rates for mature oil palms.
In Malaysia, four soil conservation practices are oft en recommended for non-terraced oil palm (E... more In Malaysia, four soil conservation practices are oft en recommended for non-terraced oil palm (Elaeis guineensis Jacq.) plantations. Th ese practices are oil palm empty fruit bunches (EFB), Ecomat (a compressed EFB mat; ECO), and pruned oil palm fronds. Th ese three oil palm residues are used as organic mulching materials. Th e fourth method is silt pits (SIL) which are soil trenches to collect nutrients from runoff water and later redistribute them back into the soil. Nonetheless, the relative eff ectiveness of these four methods in improving soil and oil palm properties have never been studied. A 3-yr fi eld experiment was consequently conducted to determine their relative eff ects on increasing soil chemical properties (pH, cation exchange capacity, organic C, total N, available P, and exchangeable K, Ca, and Mg) and oil palm nutrition levels (N, P, K, Ca, and Mg). Biomass decomposition rate and nutrients release rate in the fi eld by the three mulching materials were also determined. Results showed that EFB mulching was signifi cantly better than the other three soil conservation practices in improving nearly all of the measured soil and plant parameters. Empty fruit bunches was most eff ective partly because of the combined eff ects of higher amounts of dry matter added and the higher nutrient concentrations in the EFB than in other mulching materials. Silt pitting was found not to be as eff ective as EFB because SIL could only trap and return nutrients back into the soil, whereas EFB could do both: trap nutrients and release additional nutrients into the soil as it decomposes.
In Malaysia, four soil conservation practices are oft en recommended for non-terraced oil palm (E... more In Malaysia, four soil conservation practices are oft en recommended for non-terraced oil palm (Elaeis guineensis Jacq.) plantations. Th ese practices are oil palm empty fruit bunches (EFB), Ecomat (a compressed EFB mat; ECO), and pruned oil palm fronds. Th ese three oil palm residues are used as organic mulching materials. Th e fourth method is silt pits (SIL) which are soil trenches to collect nutrients from runoff water and later redistribute them back into the soil. Nonetheless, the relative eff ectiveness of these four methods in improving soil and oil palm properties have never been studied. A 3-yr fi eld experiment was consequently conducted to determine their relative eff ects on increasing soil chemical properties (pH, cation exchange capacity, organic C, total N, available P, and exchangeable K, Ca, and Mg) and oil palm nutrition levels (N, P, K, Ca, and Mg). Biomass decomposition rate and nutrients release rate in the fi eld by the three mulching materials were also determined. Results showed that EFB mulching was signifi cantly better than the other three soil conservation practices in improving nearly all of the measured soil and plant parameters. Empty fruit bunches was most eff ective partly because of the combined eff ects of higher amounts of dry matter added and the higher nutrient concentrations in the EFB than in other mulching materials. Silt pitting was found not to be as eff ective as EFB because SIL could only trap and return nutrients back into the soil, whereas EFB could do both: trap nutrients and release additional nutrients into the soil as it decomposes.
The main objectives of this study were to determine the physical changes in oil palm empty fruit ... more The main objectives of this study were to determine the physical changes in oil palm empty fruit bunches (EFB) and EFB mat (Ecomat), which were used as soil mulching materials, during their decomposition in the field, as well as to compare the soil water content under these mulches and with bare soil. A field experiment was conducted at an estate using ten-year-old oil palm trees. Experimental design was a Randomized Complete Block with two treatments (EFB and Ecomat) and three replications. EFB was applied at 1000 kg palm-1 as a single layer on the soil surface. Ecomat was applied as a single layer with an area of 4 m2. Physical properties of EFB and Ecomat, measured every two month for six months, were bulk density, water content, water retention, and saturated hydraulic conductivity. Soil water content up to 750 mm depth was further measured on a daily basis. Results showed that EFB was better than Ecomat as a mulching material to conserve soil water. As compared to Ecomat, EFB had a lower bulk density (two times less dense), higher saturated hydraulic conductivity (about two times higher) and higher water content (between 20 to 57% more water). EFB was also found to hold its water more strongly than Ecomat. On average, the soil under EFB mulches had, nearly 27% more water than the soil under Ecomat mulches, and 38% more than bare soil. The soil under Ecomat mulches had only 8% more water than bare soil on average. Based on the model simulations, 5 layers of Ecomat would conserve as much soil water as 1 layer of EFB. Both mulching materials were estimated to fully decompose in the field in about 9 months.
The hydrological condition and its related moisture characteristics of the soil are important fac... more The hydrological condition and its related moisture characteristics of the soil are important factors contributing to forest and plant growth in peatland ecosystem. These hydrological characteristics would also provide an indirect view point of the current management practices in the case of land cover other than natural forest. This paper reports our recent research findings on the behavior of field hydraulic conductivity (K) and moisture characteristics of peatlands typically found in Sarawak. The field hydraulic conductivity measurements were carried out on different forest types, namely mixed peat swamp, Alan forest and Padang Alan forest in the virgin peat swamp forest at Loagan Bunut National Park using auger hole and pumping method.. The moisture characteristics of peat materials were obtained from samples taken from different areas in Sarawak representing different degrees of peat decomposition under various agronomic practices. The moisture characteristic determination was conducted in the laboratory using a combination of sand/kaolin box for suction pressure less than 500 cm (pF<2.7; < 0.5 bar) and pressure membrane apparatus for 500-15000 cm (pF 2.7-4.2 or 0.5-15 bar).
Boron (B) deficiency is a frequent issue in the oil palm plantation. The symptoms can be observed... more Boron (B) deficiency is a frequent issue in the oil palm plantation. The symptoms can be observed in the leaf malformations namely hook leaf , crinkle leaf , transient leaf, , fish bone leaf and stump leaf form. These symptoms of leaf malformation are due to leaf lamina development interference which leads to reduction of photosynthetic activity. As B deficiency increases, leaf area and yields slowly decreases and in severe cases no fruit is produced. The common belief that B is not an important nutrient in the early growth stage of oil palm is actually a misconception. Theoretically, continuous supply of B is necessary to prevent the occurrence of deficiency symptoms at an early growth stage of oil palm. Due to its essentially to the crop and the lack of attention given to this micro nutrient this research has been initiated to establish a relationship between B and N fertilization. It is hoped that the outcome of this research will lead to new approaches on effective B management ...
The hydrological condition and its related moisture characteristics of the soil are important fac... more The hydrological condition and its related moisture characteristics of the soil are important factors contributing to forest and plant growth in peatland ecosystem. These hydrological characteristics would also provide an indirect view point of the current management practices in the case of land cover other than natural forest. This paper reports our recent research findings on the behavior of field hydraulic conductivity (K) and moisture characteristics of peatlands typically found in Sarawak. The field hydraulic conductivity measurements were carried out on different forest types, namely mixed peat swamp, Alan forest and Padang Alan forest in the virgin peat swamp forest at Loagan Bunut National Park using auger hole and pumping method.. The moisture characteristics of peat materials were obtained from samples taken from different areas in Sarawak representing different degrees of peat decomposition under various agronomic practices. The moisture characteristic determination was conducted in the laboratory using a combination of sand/kaolin box for suction pressure less than 500 cm (pF<2.7; < 0.5 bar) and pressure membrane apparatus for 500-15000 cm (pF 2.7-4.2 or 0.5-15 bar).
INTRODUCTION Malaysia and Indonesia are the two largest producers of palm oil in the world. In Ma... more INTRODUCTION Malaysia and Indonesia are the two largest producers of palm oil in the world. In Malaysia, oil palm occupies over four million hectares, occupying about 12% of Malaysia's land area. One of the by-products of the palm oil milling process is the empty fruit ...
Problem statement: The oil palms are mainly grown in the humid tropics with high rainfall. Solubl... more Problem statement: The oil palms are mainly grown in the humid tropics with high rainfall. Soluble Nitrogen (N) and Potassium (K) fertilizers are commonly required by the oil palm plantations to maximize palm productivity due to the highly weathered soils with low fertility. Thus, leaching losses of N and K nutrients may be unavoidable and these nutrients may move further downward and eventually cause groundwater pollution. This study reports the leaching of N and K nutrients in a mature oil palm field as affected by fertilizer rates and soil depths and its effect on groundwater quality during the monsoon period in Tawau, Sabah. Approach: The sources of N and K fertilizer were Ammonium Chloride (AC) and Muriate of Potash (MOP), respectively. Soil water samplers were installed at depths of 30, 60 and 120 cm in four fertilizer treatments, namely, N0P0K0 (Control plot, no N and K), N0P2K1 (K1 = 4.5 kg MOP palm −1 year −1 ), N1P2K1 (N1 = 3.75 AC kg palm −1 year −1 ) and N1P2K0. Three replications were used in the experiment. Monitoring wells were installed in the above treatment plots and in another treatment, N2P2K1 (N2 = 7.5 kg AC palm −1 year −1 ) to investigate the effect of excessive N rate on groundwater quality. Samplings were done at 15 day intervals for a duration of 150 days from . Results: The mean NH 4 -N concentration of N1P2K1 at 33.69 mg L −1 was significantly higher than N1P2K0 at 8.15 mg L −1 . In the presence of K, NH 4 -N concentrations increased 4.1 fold when N fertilizer was applied and 3.5 times in the absence of N application. The mean NH 4 -N concentration was 17.89 mg L −1 at 30 cm depth declining to 12.19 and 6.52 mg L −1 at soil depths of 60 and 120 cm, respectively. The transformation of NH 4 -N to NO 3 -N was not a major process during the monsoon period. The leaching losses of inorganic N were 1.0 and 1.6% of the applied fertilizer for N1P2K0 and N1P2K1 respectively. For K, the leaching losses were 5.3 and 2.4% for N0P2K1 and N1P2K1 respectively. The concentrations of NH 4 -N, NO 3 -N and K in groundwater ranged from 0.23-2.7, 0.07-0.25 and 0.63-9.54 mg L −1 , respectively. Conclusion/Recommendations: N and K concentrations in the soil solution decreased with soil depth and their leaching losses were related to rainfall pattern, fertilizer treatment and nutrient uptake by roots. Groundwater quality was not affected by the applications of N and K fertilizers at the optimum rates for mature oil palms.
In Malaysia, four soil conservation practices are oft en recommended for non-terraced oil palm (E... more In Malaysia, four soil conservation practices are oft en recommended for non-terraced oil palm (Elaeis guineensis Jacq.) plantations. Th ese practices are oil palm empty fruit bunches (EFB), Ecomat (a compressed EFB mat; ECO), and pruned oil palm fronds. Th ese three oil palm residues are used as organic mulching materials. Th e fourth method is silt pits (SIL) which are soil trenches to collect nutrients from runoff water and later redistribute them back into the soil. Nonetheless, the relative eff ectiveness of these four methods in improving soil and oil palm properties have never been studied. A 3-yr fi eld experiment was consequently conducted to determine their relative eff ects on increasing soil chemical properties (pH, cation exchange capacity, organic C, total N, available P, and exchangeable K, Ca, and Mg) and oil palm nutrition levels (N, P, K, Ca, and Mg). Biomass decomposition rate and nutrients release rate in the fi eld by the three mulching materials were also determined. Results showed that EFB mulching was signifi cantly better than the other three soil conservation practices in improving nearly all of the measured soil and plant parameters. Empty fruit bunches was most eff ective partly because of the combined eff ects of higher amounts of dry matter added and the higher nutrient concentrations in the EFB than in other mulching materials. Silt pitting was found not to be as eff ective as EFB because SIL could only trap and return nutrients back into the soil, whereas EFB could do both: trap nutrients and release additional nutrients into the soil as it decomposes.
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